Date   

Re: Mach2 Notification Question

Larry Phillips
 

OK. But how many days would that be?  I will be off the grid for a while soon and it would be my luck that my notice came and expired while I was gone.
Larry


Re: Case Foam CUTTING PATTERNS for AP Mounts

dang.astro
 

I used mycasebuilder.com for my Mach1 case. Couldn't be happier. I designed it on their web based software. Works perfect and space is maximized for the size of the case. I took a picture of the profile of my mount and traced the outline using their software. Careful measuring is needed to check and verify the pattern but totally worth it.

Cheers
Dan




Re: Mach2 Notification Question

dvjbaja
 

A response by "X" date would be in the email or letter you receive. 

jg

On Fri, Apr 17, 2020 at 1:51 PM Larry Phillips <llp41astro@...> wrote:
When a person is notified that they are eligible to purchase a Mach2, how long do they have to reply?
Larry


Mach2 Notification Question

Larry Phillips
 

When a person is notified that they are eligible to purchase a Mach2, how long do they have to reply?
Larry


Re: Mach2 quick update

Dean Jacobsen
 

On Fri, Apr 10, 2020 at 08:24 AM, uncarollo2 <chris1011@...> wrote:
Hi Astronuts,
 
Just a quick update on the progress of Mach2 mounts. We are still working at AP to get mounts out the door. Although the factory itself is shut down for now, we have a number of employees working at home assembling parts and sub-assemblies for the mounts. Fortunately our suppliers are still able to ship parts such as motors, bearings, gears, fasteners, so we are in good shape there. I'm doing all the final assemblies and testing, which is coming right along. We should be able to ship more out in the coming week, so please be patient.
 
Meanwhile I am also testing the mounts under real sky conditions with a fairly big scope and camera so I can make some guidelines on the best way to do guided and unguided imaging. More on that later.
 
Roland Christen
Astro-Physics Inc.
These quick updates are greatly appreciated.  I'm sure that I'm not the only one who would appreciate a quick note as to how things are going whenever you have time.
 
--
Dean Jacobsen
http://astrophoto.net/wp/ 
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


Re: RAPAS on Mach2

Mike Shade
 

Thanks...the old method of drifting is a major pain but seems to work well for me and my setup.  It seems to change ever so slightly over the year, likely metal heat cycling in the AZ summer heat.  The PW 17 is a workhorse, when I check polar alignment I also check collimation.  That seems to hold pretty well, haven't had to tweak in a bit.  I also have AP scopes as well, those are cycle off and on of my old 1200GTO.

 

Curious as to where you were thinking of looking for property...that might be a topic for off-list though.

 

Mike J. Shade

Mike J. Shade Photography:

mshadephotography.com

 

In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west.  Can it be half

a year since I watched her April rising in the east?  Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights

 

International Dark Sky Association: www.darksky.org

 

From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Terri Zittritsch
Sent: Thursday, April 16, 2020 3:59 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] RAPAS on Mach2

 

On Thu, Apr 16, 2020 at 06:45 PM, Mike Shade wrote:

Using the traditional drift alignment method with an illuminated reticle eyepiece, I get round stars near the zenith with my first generation 1600GTO with a five minute unguided exposure, PEC on.  This is with a Planewave CDK 17, 2940mm fl, image scale .63"/pixel, permanent observatory setup.  Never had much use for or luck with software assisted polar alignment, although some people do.  Many years ago I had one of the red robotic mounts from "the other guys" and used their polar alignment program built into their pointing program.  Never seemed to give the same answers though.  The drift does take a bit though but as it is something I check about once a year, not that big of a deal.

Mike,
That is impressive!     This is what I want.. a once a year checkup on polar alignment!     The Planewave's are also something I've had my eye on!    We were planning to find a place with 10-20 acres this spring, and covid has put a damper on our moving for the time being.     Before the Planewave, I need an observatory!


Terri


Re: RAPAS on Mach2

Terri Zittritsch
 

On Thu, Apr 16, 2020 at 06:45 PM, Mike Shade wrote:
Using the traditional drift alignment method with an illuminated reticle eyepiece, I get round stars near the zenith with my first generation 1600GTO with a five minute unguided exposure, PEC on.  This is with a Planewave CDK 17, 2940mm fl, image scale .63"/pixel, permanent observatory setup.  Never had much use for or luck with software assisted polar alignment, although some people do.  Many years ago I had one of the red robotic mounts from "the other guys" and used their polar alignment program built into their pointing program.  Never seemed to give the same answers though.  The drift does take a bit though but as it is something I check about once a year, not that big of a deal.

Mike,
That is impressive!     This is what I want.. a once a year checkup on polar alignment!     The Planewave's are also something I've had my eye on!    We were planning to find a place with 10-20 acres this spring, and covid has put a damper on our moving for the time being.     Before the Planewave, I need an observatory!


Terri


Re: Case Foam CUTTING PATTERNS for AP Mounts

fl.lusen
 

Wow Joe, you have really given this a lot of thought.  For my money a bit overkill.  Me thinks the dimensions do not need to be as exacting as you depict them.  Case in point is the shipping box inserts from AP when you buy a new mount.  To do away with the cardboard box one could built a box using 1/2" or 3/8" cabinet grade plywood with a hinged top to the same dimensions as the original shipping box.  You could supplement with the pool noodles as you say.  I would be weary of any foam you got to first insure that there would not be any out gassing since most foam is treated with formaldehyde.

Just my thoughts.

Fred


-----Original Message-----
From: Joe Zeglinski <J.Zeglinski@...>
To: main <main@ap-gto.groups.io>
Sent: Thu, Apr 16, 2020 3:46 pm
Subject: Re: [ap-gto] Case Foam CUTTING PATTERNS for AP Mounts

Hi Fred,
 
    Therein again, lies the problem – “ACCURATE & PRECISE Mount Outline Measurements”. 
 
    We don’t have any, of reasonably good accuracy, to throw money at someone making case foam to order from gun-case experts. I suppose the same goes for any other kind of delicate instrument case foam enclosure, such as Theodolites, etc.
 
    Even worse, if we had AP-provided accurate outlines with dimensions of our “specific” AP mount model, their case layout job would still not prove entirely satisfactory. Making a foam fit a regular rifle, pistol, or small canon, even a refractor, is fairly straight forward. But, we have the additional Rotational Dimension of the RA Fork/Base angle,  “rotated” from its upper saddle and angled in the Forks, differently for every individual’s local Latitude unless one unbolts the saddle, every time. The RA section will still be “oddly-placed”.
 
*******
    To solve that extra problem, I think it would make things easier, to purchase  such “foam-shaping services”, as you mention, if we could send them  an “official” outline with annotated dimensions  for our mount, especially the individually RA adjusted base configuration. That would result in a satisfactory foam insert, the first time, instead of multiple refits, lost scope time, costs, etc. for something so simple.
 
    Something I thought of subsequently, was to make an RA “rotatable foam disk BASE section”, inserted into a circular cut-out in the case foam, with its fixed DEC (and upper  RA Head and Saddle) section, which never changes shape. The small remaining piece, which does depend on Latitude, is the Forks with its Base and RA axle.
 
    If THAT pattern could be cut into a separate, circular foam disk, then the owner, or fabricator, could insert/rotate the foam disk so the Fork/Base fits the angle of the permanent, fixed cut-out of the rest of the RA & Saddle section. It would likely be a one-time fitting, but easily readjusted if a person moves to a new home, or other regular long term observatory site. Then, you wouldn’t need a new case foam insert – simply,  rotate the foam disk. Manufacturing the special fit foam,  would be easy, quick, and done in just one fitting.
 
    Then again, wouldn’t this be a great Service that could be done via Astro-Physics?
No need to inventory, “case products”, depend on telescope case makers to survive in business, or have long delay times, for every user request, and AP could hook-up with one or more such CASE “Gun-Foam” shapers, to pass our orders through, instead of everyone hunting (pun),for their own supplier, or hacking out their own case foam blocks – possibly repeated if the user eventually wears out or damages the foam, or gets tired of their particular scope “Luggage” (double-entendre pun).
 
    Or, as I originally suggested, at least AP could provide the GROUP,  a set of printable stitching diagrams to hack out, sculpt,  ( or case “foam-pluck”) our own foam inserts.
 
**** Did we get the Mount CASES all wrong, these many years ? *****
 
    Another approach, cases WITHOUT much foam, none of these actually sculpted,  inside them at all – Consider ... “AIR CUSHIONED CASES”.
 
    Foam line any Cube Case with flat foam squares,  then insert an air bag - possibly made of rugged beach mattress canvass material - and inflate it with a bicycle pump,  or car tire battery-operated “inflator”,  with the RA section sitting (approximately) in the middle of the air bag. If its shape is loose enough, its INSIDES will mostly CONFORM to the RA assembly (minus the Saddle’s D-Plate), The base and lid/top would be thicker normal foam squares, for vertical protection. For extra vertical confinement, the lid case foam could have a simple cut-out layer, loosely the shape of the saddle, to restrain the mount inside the semi-flexing (depending on inflation pressure)  air bag. Then the RA section can bounce around even in rough travel, but can never actually hit the sides of the (possibly additional),  foam lined hard case walls.
 
   Or, just Make your own Case Inner Tube – using a kid’s toy   Visit TOYS R’ US (see below)
 
    Fill it up (sufficiently) to conform to the RA section. sitting on the base foam cushion. Buy and stack two of these, if needed, and at least as a “partial spare tire backup” inside,  if one gets accidentally punctured. Make inflating & deflating easy and quicker – by attaching a regular bicycle pump hose to the air inlet(s), and lead it/them to  outside of the case wall, for easier access.
For example:

48" Gold Hologrpahic Glitter Pool Tube  - and/or -   Big Boss 4"X58" Pool Noodles

    and .....
 
48
 
    I suppose, an alternative Air Cushioned Travel vehicle, rather than a special-sized cubic air bag, would be to buy, “vey baggy” inflatable air seat cushions, to insert or prop up, against the case walls. Once they are “hard-inflated”, as above, they would provide the similar side protection, as a conformal inflatable bag with less cost and better availability. Any extra corner space can additionally be stuffed with vertically positioned  regular small foam “waist support” (e.g. porch swing) cushions,  or those cut from lengths of swimming pool toy “flexible but stiffer, Styrofoam - Pool Noodles”, as above,  (with its cushioning center air channel hole)”.
 
    A nice BONUS - when you are tired, packing up the mount case in the cold (winter) dark night  for the long trip home, trying (otherwise) to not damage a case’s foam outline as you might otherwise with a regular foam case: - 
... You still have your handy bicycle pump, or even far better - the cigarette lighter plug (from the car,  or telescope power pack),  DC-operated air pump, to quickly, “hard re-inflate” the case air cushion(s).
 
    Just a thought ... too much ?
Joe Z.


Re: RAPAS on Mach2

Terri Zittritsch
 

On Thu, Apr 16, 2020 at 05:25 PM, W Hilmo wrote:

No problem.  Likewise, I’m just trying to offer some suggestions.

Wade, I appreciate the calm dialog.    Thank you.

I tend to be overly verbose when I write, which probably overcomplicates things.  It probably wasn’t clear, but I’ve ever even used an eyepiece with my two main imaging scopes.  Everything that I’ve suggested is intended to be “imaging rig friendly” and fairly simple to do.

No worries.   

Regarding your previous attempts to image unguided, what kind of scope are you using?  I do most of my imaging with an EdgeHD 8, and I simply cannot do unguided imaging with it with any kind of regularity.  The issue is that the primary mirror just has too much movement, even with the focus clutches locked.  There is obvious star trailing after 3 minutes, and 5 minute subs are completely unusable to me.  I have to use an OAG.  An APPM model doesn’t really help a lot with this because the mirror movement seems to be non-repeatable.



I have numerous scopes, but most recently it's been a Stowaway and a TEC140.  The Stowaway was being used at only 492mm , with reducer/corrector while the Tec was being used at, I think plate solving thinks it's 1037mm.    I use the A-P corrector which seems to increase the focal length a little.   

I started AP with an SCT 'Franken-rig'  with lightweight wedge, fork, and a wild assortment of weights to balance the whole thing.  I ended up with OK images.   Once I bought an Atlas, I deforked the meade 8" and ended up with much rounder stars.   That lightweight wedge only had to be breathed on and it would wobble... a huge challenge. but I always got it to work.    With the Meade 8" on the Atlas, my primary exposure was 5 minutes, unless I was imaging something really bright, where I might reduce to 2 or 3 minutes, or really dim, and I'd go to 6 minutes.   I was able to do acceptable work there, although I can do much better now.   My SCT had no mirror lock, and it worked acceptably well.  My Meade didn't have any mirror shift either (I must have been lucky).    I have since re-forked it now, and use it for outreach a lot.. it gives amazing views in a small package.    In fact, usually better views than most of the clubs 10" reflectors, and one 12",  they bring to the events.    Before anyone poo-poos this, they aren't Lockwood mirror scopes, but at least one is done by a local mirror grinding pro, and my SCT gives them a run for their money.
I use a 400mm Orion guide scope and lode star with the TEC140.   With the Stowaway, I have a 240mm guidescope with AS290 (small pixels) for better guiding resolution, or so I think.





When you do an APPM run, how much of the time is spent waiting for the image to download?  I was using a CMOS camera with USB 3 downloads for a while, and it would download a 1x1 frame in just a couple of seconds.  My current camera is a CCD with USB 2, and it takes a *long* time to download a 1x1 frame.  To mitigate this, I do 5 second exposures with 2x2 binning whenever I plate solve (either inside of SGP or with APPM).  That speeds things up considerably.  I spend less than an hour to get 100-150 points.  I suspect that your DSLR can probably download a lower resolution as well.  The last time that I binned a DSLR was many years ago with a Canon 20D, and it lost the Bayer matrix information when binned 2x2, but that was no big deal for plate solving.


I do need to try binning, I do 1x1 today, and use an ASI1600 or an ASI071.   I stopped using DSLRs around 18 mo. or so ago.   So it does takes far too long.. much longer than USB3 would indicate it should.  Many people complain about this on SGPro, but they've not been able to fix it, or it's a driver issue and I've stopped following the discussion.     It is what it is at this point, and for AP it's not a huge deal.    I should try 2x2 binning, and even thought it's all software, maybe i'll result in smaller file transfer if the downsizing happens in the camera.  If it happens at the computer, not much to be gained.   CMOS sensors do not bin in the same sense that CCD sensors do.    Once the image is at the computer, the plate solve is quite fast and usually after the first solve, they all happen very fast.

My personal opinion that is unguided imaging is not something that interests me much.  It takes me about an hour to really dial in a new guider (what with focusing through my OAG and such), but once I’ve done that, it’s all automatic.  Since I always set up with the camera, OAG and guider at the same orientation, I don’t even need to recalibrate the guide software after setting up.


At this point just trying to see what the high performance of the mount gets me.   I know it's made much better than my Atlas's (I have an old and new pro belt drive), but so far I've not been able to get significant and consistently better performance.   My last time out, I was imaging M101 and my RMS was .64 arc sec and M101 is pretty high in the sky.    I acknowledge it could be all seeing too, so my wanting better performance could be a pipe dream.     It could be that living in Vermont I should have taken up a more reliable hobby, like quilting, rather than astrophotography given our lack of clear and stable skies.     But I am a gluten for punishment.   Most of my AP is done in the dead of winter, unshielded by walls or an observatory in frigid weather (certainly not a sissy... smile) and dealing with at least one gotcha a night that requires some amount of debug.  I guess if the Mach2 gets rid of the gotchas, it'll be an improvement.  

I am an EE semiconductor engineer myself, so I have a fondness for finely made mechanical things..   It is pretty!   



Terri




Re: RAPAS on Mach2

Mike Shade
 

Using the traditional drift alignment method with an illuminated reticle eyepiece, I get round stars near the zenith with my first generation 1600GTO with a five minute unguided exposure, PEC on.  This is with a Planewave CDK 17, 2940mm fl, image scale .63"/pixel, permanent observatory setup.  Never had much use for or luck with software assisted polar alignment, although some people do.  Many years ago I had one of the red robotic mounts from "the other guys" and used their polar alignment program built into their pointing program.  Never seemed to give the same answers though.  The drift does take a bit though but as it is something I check about once a year, not that big of a deal.

 

Mike J. Shade

Mike J. Shade Photography:

mshadephotography.com

 

In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west.  Can it be half

a year since I watched her April rising in the east?  Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights

 

International Dark Sky Association: www.darksky.org

 

From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of W Hilmo
Sent: Thursday, April 16, 2020 1:15 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] RAPAS on Mach2

 

Honestly, I’ve never measured my polar alignment error.

 

Beyond that, I don’t even know how to measure it in a way that would be useful in conversation.  I don’t know if you follow Cloudy Nights or not, but there is a near obsession over there with polar alignment.  I’ve seen people making polar alignment error claims that border on the ridiculous (like people claiming to be within 5” of the pole, etc.)  The drift from a 5” polar alignment error would be so small that I don’t know how you could detect it with a single exposure.  I would think that looking at the total field rotation for an entire night would be a better way to try and see a very small error.  I am pretty sure that people are just running some tool like a PoleMaster or SharpCap and just repeating what the software claims.  The thing is, that the software claims are not repeatable, even in the same session.  It’s made even more confusing because I am pretty sure that different software packages calculate the polar alignment error differently.

 

Even with PEMPro, which is the gold standard for software aided drift alignments, I can watch the calculated error bounce around by some number of arc seconds with each exposure, just due to seeing effects.

 

I take a more pragmatic view.  If I don’t get any noticeable drift in a single sub, and if I don’t get any field rotation over a night of imaging the same object, then I’ll call the polar alignment “good enough”.  If your goal is to do longish exposures unguided, especially at a longer focal length, then I would probably do it one of two ways:  If you take the time to run APCC, an APPM model will compensate for any polar misalignment, as well as drift from other factors (as long as they are repeatable).  That would be my preferred method.  If I didn’t want to do an APPM run for some reason, then I would do the RA Drift Alignment that’s described on the Astro-Physics site at the below link.  To do it, I would run PHD2 with my main imaging camera and guide corrections disabled.  This would give me a graph of the guide star during tracking that I could use to know which corrections to make:

 

https://astro-physics.info/tech_support/mounts/drift-alignment-ra-correction-method.pdf

 

The other option, that is new to the keypad firmware that will be available for the Mach2, will be that you can get tracking compensation right from the keypad (and it will also be available for the CP4).  I don’t believe that any of us have that keypad firmware yet, so I don’t know of anyone outside of the Astro-Physics folks that have first hand experience with it.  If I understand what I’ve heard correctly, it will work by calibrating on a couple of stars in the path of your object and building custom tracking rates for your specific target.  I’m guessing that it will be pretty effective.

 

At the end of the day, I believe that it’s important to understand a few methods to do an  effective polar alignment and also to not obsess over it.

 

In the meantime, how do you know that your polar alignment is causing problematic drift?  If the Mach2 ships with PEMPro, I would suggest that you start its polar alignment wizard and let it track for a while.  It will clearly show you any drift (and offer the change to make an adjustment to correct it).  If you don’t have PEMPro, then you can do a similar thing with PHD2 (as I described above, using it to facilitate a drift alignment).

 

And finally, I want to close the loop on a comment that I made earlier about my personal workflow at field sites.  I mentioned that I do both a daytime polar alignment and also use the RAPAS to tweak it.  The purpose of the daytime polar alignment is to get the mount reasonably close to polar aligned before it starts to get dark.  That way, when it gets to be dusk, you are pretty much guaranteed that Polaris will be both inside the view of the RAPAS and also obvious.  If you wait until after dark and start with the RAPAS, it can be tricky to find Polaris correct, especially if it lands outside of the RAPAS field of view.  In that case, it takes longer than 30 seconds (and I’ve seen more than one person polar align to Kochab in that scenario).

 

Hope that you find this information useful,

-Wade

 

 

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Terri Zittritsch
Sent: Thursday, April 16, 2020 12:30 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] RAPAS on Mach2

 

Thanks W Hilmo,

Not sure I ever see field rotation with any of my gross polar alignment methods.  I think you'd have to be pretty far off to see field rotation (but honestly don't know what that would be).  I'm trying to understand what kind of measured repeatable polar alignment people get.    Is 2 minutes, 3 minutes?   30 seconds?   With Polemaster, it's advertised at 30", and I see all kinds of claims on-line (hard to believe claims.. and claims that would be hard to even measure), but who knows.  Maybe I am just the worst polar aligner ever.    If I can do an accurate polar alignment (30") in 30 seconds, I will be exceptionally happy!!   I've never tried the daytime polar alignment.


Terri


Re: RAPAS on Mach2

Roland Christen
 

Hi All,

Just want to throw this trick into the mix. I've posted this before in more detail, but I'll keep it very simple. If you don't want to use a polar scope:

After basic polar alignment (any basic method that gets you close) I send the scope to a star at or very near the zenith and take an image. It won't be in the center, but hopefully somewhere in the frame. I put the exposure on "continuous" and center the star, followed by a recal. This is my overhead reference star for the next step.

Step 2, I slew to a star in the south near the meridian line and on the same side of the meridian. I then use the Azimuth adjuster to bring that star to the centerline in the RA direction. Dec may have an error, but ignore that. That's it, you're done with the Azimuth axis. Takes about 2 minutes.

Now all you have left is the Altitude axis. That adjustment can be done by doing a meridian delay and slewing to that same star in the south on the opposite side. Now bring the star 1/2 way to the centerline using the altitude axis. RA may have an error but ignore that. That's it, you are polar aligned. Takes maybe another 2 - 3 minutes.

I might then watch the overhead star drift and maybe tweak the alignment, usually requires very tiny amount of adjustment if any. Usually good enough for 5 minute exposures with an 800mm focal length.

Rolando



-----Original Message-----
From: W Hilmo <y.groups@...>
To: main <main@ap-gto.groups.io>
Sent: Thu, Apr 16, 2020 4:25 pm
Subject: Re: [ap-gto] RAPAS on Mach2

“Hi Wade, peace..  just trying to understand.”
 
No problem.  Likewise, I’m just trying to offer some suggestions.
 
I tend to be overly verbose when I write, which probably overcomplicates things.  It probably wasn’t clear, but I’ve ever even used an eyepiece with my two main imaging scopes.  Everything that I’ve suggested is intended to be “imaging rig friendly” and fairly simple to do.
 
Regarding your previous attempts to image unguided, what kind of scope are you using?  I do most of my imaging with an EdgeHD 8, and I simply cannot do unguided imaging with it with any kind of regularity.  The issue is that the primary mirror just has too much movement, even with the focus clutches locked.  There is obvious star trailing after 3 minutes, and 5 minute subs are completely unusable to me.  I have to use an OAG.  An APPM model doesn’t really help a lot with this because the mirror movement seems to be non-repeatable.
 
When you do an APPM run, how much of the time is spent waiting for the image to download?  I was using a CMOS camera with USB 3 downloads for a while, and it would download a 1x1 frame in just a couple of seconds.  My current camera is a CCD with USB 2, and it takes a *long* time to download a 1x1 frame.  To mitigate this, I do 5 second exposures with 2x2 binning whenever I plate solve (either inside of SGP or with APPM).  That speeds things up considerably.  I spend less than an hour to get 100-150 points.  I suspect that your DSLR can probably download a lower resolution as well.  The last time that I binned a DSLR was many years ago with a Canon 20D, and it lost the Bayer matrix information when binned 2x2, but that was no big deal for plate solving.
 
My personal opinion that is unguided imaging is not something that interests me much.  It takes me about an hour to really dial in a new guider (what with focusing through my OAG and such), but once I’ve done that, it’s all automatic.  Since I always set up with the camera, OAG and guider at the same orientation, I don’t even need to recalibrate the guide software after setting up.
 
-Wade
 
From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Terri Zittritsch
Sent: Thursday, April 16, 2020 1:57 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] RAPAS on Mach2
 
Hi Wade, peace..  just trying to understand.    Like I said in my original post, it may be that I'm just seeking something that isn't really practical or possible.   I have a full guiding setup, but when I get these posts using encoder mounts or my mount, showing incredibly flat controlled tracking, I'm trying to see if I can achieve this as well.     

I see the same things in forums, on claims of incredibly precise polar alignment, and as I said in the previous post, I don't know how they can make such claims.  I spent an hour one night polar drift alignment and had better alignment than usual, but it took an hour, and it still wasn't good enough for very long subs.   Long subs for me, with a CMOS camera, are still under 10 minutes or less.  I've done 20 minutes, but it's unusual.   Most of my subs are 1 minute (luminosity).    Although, having purchased some chroma 3nm filters, those seem to take some really long exposures to get a good amount of signal!

I measure drift in PHD2, using their drift alignment tool.. which takes forever to settle.. so it's a long process (for me).   Usually when I'm doing  polar alignment, I'm set up with camera, filter wheel, etc.. and want to do something that doesn't require me to take it apart and put in an eyepiece.    And PHD2 also gives me an estimate of my polar alignment error, which is based on drift, not instantaneous bouncing around the mean which I understand is all atmosphere.

I've only done one model, a 35 point small model, and I think it took around 25 minutes (it's been a while since clear skies).    And most of the plate solves were pretty fast.    I noticed the meridian points, solved twice, and most others once, so it does more than 35 solves for 35 points.    I use SGPro, which seems a bit slow to download files from my camera, which may make it slower than others.    The results of the 35 point model did not allow 1 minute subs, and I had unacceptably elongated stars.      But that's one data point,  and there is a lot to learn.  


Terri


Re: RAPAS on Mach2

W Hilmo
 

“Hi Wade, peace..  just trying to understand.”

 

No problem.  Likewise, I’m just trying to offer some suggestions.

 

I tend to be overly verbose when I write, which probably overcomplicates things.  It probably wasn’t clear, but I’ve ever even used an eyepiece with my two main imaging scopes.  Everything that I’ve suggested is intended to be “imaging rig friendly” and fairly simple to do.

 

Regarding your previous attempts to image unguided, what kind of scope are you using?  I do most of my imaging with an EdgeHD 8, and I simply cannot do unguided imaging with it with any kind of regularity.  The issue is that the primary mirror just has too much movement, even with the focus clutches locked.  There is obvious star trailing after 3 minutes, and 5 minute subs are completely unusable to me.  I have to use an OAG.  An APPM model doesn’t really help a lot with this because the mirror movement seems to be non-repeatable.

 

When you do an APPM run, how much of the time is spent waiting for the image to download?  I was using a CMOS camera with USB 3 downloads for a while, and it would download a 1x1 frame in just a couple of seconds.  My current camera is a CCD with USB 2, and it takes a *long* time to download a 1x1 frame.  To mitigate this, I do 5 second exposures with 2x2 binning whenever I plate solve (either inside of SGP or with APPM).  That speeds things up considerably.  I spend less than an hour to get 100-150 points.  I suspect that your DSLR can probably download a lower resolution as well.  The last time that I binned a DSLR was many years ago with a Canon 20D, and it lost the Bayer matrix information when binned 2x2, but that was no big deal for plate solving.

 

My personal opinion that is unguided imaging is not something that interests me much.  It takes me about an hour to really dial in a new guider (what with focusing through my OAG and such), but once I’ve done that, it’s all automatic.  Since I always set up with the camera, OAG and guider at the same orientation, I don’t even need to recalibrate the guide software after setting up.

 

-Wade

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Terri Zittritsch
Sent: Thursday, April 16, 2020 1:57 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] RAPAS on Mach2

 

Hi Wade, peace..  just trying to understand.    Like I said in my original post, it may be that I'm just seeking something that isn't really practical or possible.   I have a full guiding setup, but when I get these posts using encoder mounts or my mount, showing incredibly flat controlled tracking, I'm trying to see if I can achieve this as well.     

I see the same things in forums, on claims of incredibly precise polar alignment, and as I said in the previous post, I don't know how they can make such claims.  I spent an hour one night polar drift alignment and had better alignment than usual, but it took an hour, and it still wasn't good enough for very long subs.   Long subs for me, with a CMOS camera, are still under 10 minutes or less.  I've done 20 minutes, but it's unusual.   Most of my subs are 1 minute (luminosity).    Although, having purchased some chroma 3nm filters, those seem to take some really long exposures to get a good amount of signal!

I measure drift in PHD2, using their drift alignment tool.. which takes forever to settle.. so it's a long process (for me).   Usually when I'm doing  polar alignment, I'm set up with camera, filter wheel, etc.. and want to do something that doesn't require me to take it apart and put in an eyepiece.    And PHD2 also gives me an estimate of my polar alignment error, which is based on drift, not instantaneous bouncing around the mean which I understand is all atmosphere.

I've only done one model, a 35 point small model, and I think it took around 25 minutes (it's been a while since clear skies).    And most of the plate solves were pretty fast.    I noticed the meridian points, solved twice, and most others once, so it does more than 35 solves for 35 points.    I use SGPro, which seems a bit slow to download files from my camera, which may make it slower than others.    The results of the 35 point model did not allow 1 minute subs, and I had unacceptably elongated stars.      But that's one data point,  and there is a lot to learn.  


Terri


Re: guiding calibration woes

Eric Dreher
 

https://software.starkeeper.it


Re: guiding calibration woes

CurtisC
 

What is Voyager?


Re: RAPAS on Mach2

Terri Zittritsch
 

Hi Wade, peace..  just trying to understand.    Like I said in my original post, it may be that I'm just seeking something that isn't really practical or possible.   I have a full guiding setup, but when I get these posts using encoder mounts or my mount, showing incredibly flat controlled tracking, I'm trying to see if I can achieve this as well.     

I see the same things in forums, on claims of incredibly precise polar alignment, and as I said in the previous post, I don't know how they can make such claims.  I spent an hour one night polar drift alignment and had better alignment than usual, but it took an hour, and it still wasn't good enough for very long subs.   Long subs for me, with a CMOS camera, are still under 10 minutes or less.  I've done 20 minutes, but it's unusual.   Most of my subs are 1 minute (luminosity).    Although, having purchased some chroma 3nm filters, those seem to take some really long exposures to get a good amount of signal!

I measure drift in PHD2, using their drift alignment tool.. which takes forever to settle.. so it's a long process (for me).   Usually when I'm doing  polar alignment, I'm set up with camera, filter wheel, etc.. and want to do something that doesn't require me to take it apart and put in an eyepiece.    And PHD2 also gives me an estimate of my polar alignment error, which is based on drift, not instantaneous bouncing around the mean which I understand is all atmosphere.

I've only done one model, a 35 point small model, and I think it took around 25 minutes (it's been a while since clear skies).    And most of the plate solves were pretty fast.    I noticed the meridian points, solved twice, and most others once, so it does more than 35 solves for 35 points.    I use SGPro, which seems a bit slow to download files from my camera, which may make it slower than others.    The results of the 35 point model did not allow 1 minute subs, and I had unacceptably elongated stars.      But that's one data point,  and there is a lot to learn.  


Terri



Re: Case Foam CUTTING PATTERNS for AP Mounts

Joe Zeglinski
 

Hi Fred,
 
    Therein again, lies the problem – “ACCURATE & PRECISE Mount Outline Measurements”. 
 
    We don’t have any, of reasonably good accuracy, to throw money at someone making case foam to order from gun-case experts. I suppose the same goes for any other kind of delicate instrument case foam enclosure, such as Theodolites, etc.
 
    Even worse, if we had AP-provided accurate outlines with dimensions of our “specific” AP mount model, their case layout job would still not prove entirely satisfactory. Making a foam fit a regular rifle, pistol, or small canon, even a refractor, is fairly straight forward. But, we have the additional Rotational Dimension of the RA Fork/Base angle,  “rotated” from its upper saddle and angled in the Forks, differently for every individual’s local Latitude unless one unbolts the saddle, every time. The RA section will still be “oddly-placed”.
 
*******
    To solve that extra problem, I think it would make things easier, to purchase  such “foam-shaping services”, as you mention, if we could send them  an “official” outline with annotated dimensions  for our mount, especially the individually RA adjusted base configuration. That would result in a satisfactory foam insert, the first time, instead of multiple refits, lost scope time, costs, etc. for something so simple.
 
    Something I thought of subsequently, was to make an RA “rotatable foam disk BASE section”, inserted into a circular cut-out in the case foam, with its fixed DEC (and upper  RA Head and Saddle) section, which never changes shape. The small remaining piece, which does depend on Latitude, is the Forks with its Base and RA axle.
 
    If THAT pattern could be cut into a separate, circular foam disk, then the owner, or fabricator, could insert/rotate the foam disk so the Fork/Base fits the angle of the permanent, fixed cut-out of the rest of the RA & Saddle section. It would likely be a one-time fitting, but easily readjusted if a person moves to a new home, or other regular long term observatory site. Then, you wouldn’t need a new case foam insert – simply,  rotate the foam disk. Manufacturing the special fit foam,  would be easy, quick, and done in just one fitting.
 
    Then again, wouldn’t this be a great Service that could be done via Astro-Physics?
No need to inventory, “case products”, depend on telescope case makers to survive in business, or have long delay times, for every user request, and AP could hook-up with one or more such CASE “Gun-Foam” shapers, to pass our orders through, instead of everyone hunting (pun),for their own supplier, or hacking out their own case foam blocks – possibly repeated if the user eventually wears out or damages the foam, or gets tired of their particular scope “Luggage” (double-entendre pun).
 
    Or, as I originally suggested, at least AP could provide the GROUP,  a set of printable stitching diagrams to hack out, sculpt,  ( or case “foam-pluck”) our own foam inserts.
 
**** Did we get the Mount CASES all wrong, these many years ? *****
 
    Another approach, cases WITHOUT much foam, none of these actually sculpted,  inside them at all – Consider ... “AIR CUSHIONED CASES”.
 
    Foam line any Cube Case with flat foam squares,  then insert an air bag - possibly made of rugged beach mattress canvass material - and inflate it with a bicycle pump,  or car tire battery-operated “inflator”,  with the RA section sitting (approximately) in the middle of the air bag. If its shape is loose enough, its INSIDES will mostly CONFORM to the RA assembly (minus the Saddle’s D-Plate), The base and lid/top would be thicker normal foam squares, for vertical protection. For extra vertical confinement, the lid case foam could have a simple cut-out layer, loosely the shape of the saddle, to restrain the mount inside the semi-flexing (depending on inflation pressure)  air bag. Then the RA section can bounce around even in rough travel, but can never actually hit the sides of the (possibly additional),  foam lined hard case walls.
 
   Or, just Make your own Case Inner Tube – using a kid’s toy   Visit TOYS R’ US (see below)
 
    Fill it up (sufficiently) to conform to the RA section. sitting on the base foam cushion. Buy and stack two of these, if needed, and at least as a “partial spare tire backup” inside,  if one gets accidentally punctured. Make inflating & deflating easy and quicker – by attaching a regular bicycle pump hose to the air inlet(s), and lead it/them to  outside of the case wall, for easier access.
For example:

48" Gold Hologrpahic Glitter Pool Tube  - and/or -   Big Boss 4"X58" Pool Noodles

    and .....
 
 
    I suppose, an alternative Air Cushioned Travel vehicle, rather than a special-sized cubic air bag, would be to buy, “vey baggy” inflatable air seat cushions, to insert or prop up, against the case walls. Once they are “hard-inflated”, as above, they would provide the similar side protection, as a conformal inflatable bag with less cost and better availability. Any extra corner space can additionally be stuffed with vertically positioned  regular small foam “waist support” (e.g. porch swing) cushions,  or those cut from lengths of swimming pool toy “flexible but stiffer, Styrofoam - Pool Noodles”, as above,  (with its cushioning center air channel hole)”.
 
    A nice BONUS - when you are tired, packing up the mount case in the cold (winter) dark night  for the long trip home, trying (otherwise) to not damage a case’s foam outline as you might otherwise with a regular foam case: - 
... You still have your handy bicycle pump, or even far better - the cigarette lighter plug (from the car,  or telescope power pack),  DC-operated air pump, to quickly, “hard re-inflate” the case air cushion(s).
 
    Just a thought ... too much ?
Joe Z.
 
 
 

From: fl.lusen via groups.io
Sent: Thursday, April 16, 2020 12:32 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Case Foam CUTTING PATTERNS for AP Mounts
 
Joe,

I came across this guy at a local gun show.  https://agvii.com/custom-cases/ I am sure there are many more like him around the country.  He can use your case or provide one.  He can use your measurements or you can send him the item and he will custom fit it.  This could be another alternative.

Fred
 
 


Re: RAPAS on Mach2

Dean Jacobsen
 

On Thu, Apr 16, 2020 at 01:15 PM, W Hilmo wrote:
and I’ve seen more than one person polar align to Kochab in that scenario).
I didn’t know anyone was watching me...  🙂

I used just the RAPAS for aligning my portable imaging rig for years.  I have no idea how close it was or how repeatable it was from session to session.  It is a great time saver.
 
--
Dean Jacobsen
http://astrophoto.net/wp/ 
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


Re: RAPAS on Mach2

W Hilmo
 

Honestly, I’ve never measured my polar alignment error.

 

Beyond that, I don’t even know how to measure it in a way that would be useful in conversation.  I don’t know if you follow Cloudy Nights or not, but there is a near obsession over there with polar alignment.  I’ve seen people making polar alignment error claims that border on the ridiculous (like people claiming to be within 5” of the pole, etc.)  The drift from a 5” polar alignment error would be so small that I don’t know how you could detect it with a single exposure.  I would think that looking at the total field rotation for an entire night would be a better way to try and see a very small error.  I am pretty sure that people are just running some tool like a PoleMaster or SharpCap and just repeating what the software claims.  The thing is, that the software claims are not repeatable, even in the same session.  It’s made even more confusing because I am pretty sure that different software packages calculate the polar alignment error differently.

 

Even with PEMPro, which is the gold standard for software aided drift alignments, I can watch the calculated error bounce around by some number of arc seconds with each exposure, just due to seeing effects.

 

I take a more pragmatic view.  If I don’t get any noticeable drift in a single sub, and if I don’t get any field rotation over a night of imaging the same object, then I’ll call the polar alignment “good enough”.  If your goal is to do longish exposures unguided, especially at a longer focal length, then I would probably do it one of two ways:  If you take the time to run APCC, an APPM model will compensate for any polar misalignment, as well as drift from other factors (as long as they are repeatable).  That would be my preferred method.  If I didn’t want to do an APPM run for some reason, then I would do the RA Drift Alignment that’s described on the Astro-Physics site at the below link.  To do it, I would run PHD2 with my main imaging camera and guide corrections disabled.  This would give me a graph of the guide star during tracking that I could use to know which corrections to make:

 

https://astro-physics.info/tech_support/mounts/drift-alignment-ra-correction-method.pdf

 

The other option, that is new to the keypad firmware that will be available for the Mach2, will be that you can get tracking compensation right from the keypad (and it will also be available for the CP4).  I don’t believe that any of us have that keypad firmware yet, so I don’t know of anyone outside of the Astro-Physics folks that have first hand experience with it.  If I understand what I’ve heard correctly, it will work by calibrating on a couple of stars in the path of your object and building custom tracking rates for your specific target.  I’m guessing that it will be pretty effective.

 

At the end of the day, I believe that it’s important to understand a few methods to do an  effective polar alignment and also to not obsess over it.

 

In the meantime, how do you know that your polar alignment is causing problematic drift?  If the Mach2 ships with PEMPro, I would suggest that you start its polar alignment wizard and let it track for a while.  It will clearly show you any drift (and offer the change to make an adjustment to correct it).  If you don’t have PEMPro, then you can do a similar thing with PHD2 (as I described above, using it to facilitate a drift alignment).

 

And finally, I want to close the loop on a comment that I made earlier about my personal workflow at field sites.  I mentioned that I do both a daytime polar alignment and also use the RAPAS to tweak it.  The purpose of the daytime polar alignment is to get the mount reasonably close to polar aligned before it starts to get dark.  That way, when it gets to be dusk, you are pretty much guaranteed that Polaris will be both inside the view of the RAPAS and also obvious.  If you wait until after dark and start with the RAPAS, it can be tricky to find Polaris correct, especially if it lands outside of the RAPAS field of view.  In that case, it takes longer than 30 seconds (and I’ve seen more than one person polar align to Kochab in that scenario).

 

Hope that you find this information useful,

-Wade

 

 

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Terri Zittritsch
Sent: Thursday, April 16, 2020 12:30 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] RAPAS on Mach2

 

Thanks W Hilmo,

Not sure I ever see field rotation with any of my gross polar alignment methods.  I think you'd have to be pretty far off to see field rotation (but honestly don't know what that would be).  I'm trying to understand what kind of measured repeatable polar alignment people get.    Is 2 minutes, 3 minutes?   30 seconds?   With Polemaster, it's advertised at 30", and I see all kinds of claims on-line (hard to believe claims.. and claims that would be hard to even measure), but who knows.  Maybe I am just the worst polar aligner ever.    If I can do an accurate polar alignment (30") in 30 seconds, I will be exceptionally happy!!   I've never tried the daytime polar alignment.


Terri


Re: RAPAS on Mach2

Terri Zittritsch
 

On Thu, Apr 16, 2020 at 01:47 PM, W Hilmo wrote:

 

When I set up in the field, my general workflow is to set up the mount during the day and go through the daytime polar alignment routine.  Then, at dusk I use the RAPAS to do a final tweak to the polar alignment.  If I do this, and then blink a stack of a whole night’s imaging, there is no noticeable field rotation between the first and last images of the session.  The daytime alignment takes me two to three minutes while the sun is up, and the tweak with the RAPAS takes about 30 seconds.

 

Thanks W Hilmo,

Not sure I ever see field rotation with any of my gross polar alignment methods.  I think you'd have to be pretty far off to see field rotation (but honestly don't know what that would be).  I'm trying to understand what kind of measured repeatable polar alignment people get.    Is 2 minutes, 3 minutes?   30 seconds?   With Polemaster, it's advertised at 30", and I see all kinds of claims on-line (hard to believe claims.. and claims that would be hard to even measure), but who knows.  Maybe I am just the worst polar aligner ever.    If I can do an accurate polar alignment (30") in 30 seconds, I will be exceptionally happy!!   I've never tried the daytime polar alignment.


Terri



Re: RAPAS on Mach2

Roland Christen
 


The instructions note that you can loosen the 'do not loosen' screws to readjust the reticle if it's moved during shipping,
You can never adjust the reticle, it is permanently affixed inside the eyepiece. However the eyepiece is simply held in the back of the polar scope via a small setscrew, and this entire assembly can be rotated. We made this so you can do fine adjustment of the vertical reticle line in the field. Even if you are off several degrees it has very little if any effect on the actual polar alignment.

Rolando


-----Original Message-----
From: Terri Zittritsch <theresamarie11@...>
To: main <main@ap-gto.groups.io>
Sent: Thu, Apr 16, 2020 12:27 pm
Subject: Re: [ap-gto] RAPAS on Mach2

On Thu, Apr 16, 2020 at 11:17 AM, uncarollo2 <chris1011@...> wrote:
No need to level the mount super accurately. The polar scope will still work well even if you are off by many degrees.
 
If your mount is not vertical, you can align the polar scope reticle to be vertical:
1) Aim the mount so that the scope points directly at Polaris (put Polaris on the center crosshair).
2) using the mount's altitude adjuster, run Polaris up and down the vertical crosshair. Loosen and turn the eyepiece until the crosshair is aligned with the up-down motion of Polaris.
3) tighten the eyepiece in place and then use the alt and az adjusters to put Polaris at the proper place on the reticle according to the polar app.
 
Rolando
Roland, I didn't expect you to respond.    The RAPAS feels like the rest of the kit I have from AP, solid and built like a tank!  Being an engineer, I can appreciate it all.

Throughout the instructions I received, in numerous places, are notes to make sure the mount is level which is why I asked.  It didn't take long to think about the implications of the mount not being level, or more accurately, the RAPAS not being precisely vertical, on the accuracy on polar alignment.   The instructions note that you can loosen the 'do not loosen' screws to readjust the reticle if it's moved during shipping, but doesn't seem to be part of the normal (do every time) alignment process.   At least not in the instructions I have, so thanks for sharing this.
I'm just trying to understand whether there is any way to do really accurate polar alignment, 30" or less,  in order to do short unguided exposures, without going to the traditional drift alignment.. I've found drift alignment to be a miserable process to go through.  Life is too short, and clear skies much shorter!   I'm not setting up on a level surface, or on a pier, every night is different.   Since I have all of the equipment, guiding is not a terrible thing to have to do.   I'm just thinking I have this really really nice mount, and is there any way to take advantage of it's full capability in a portable situation.   


Terri



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