Date   

Re: Some doubts about the use of the clutch knobs on the Mach1

Roland Christen
 


I know I'm not going to damage anything, but I'm afraid it might affect the precise tracking or something.
Using the clutches will not affect your tracking, guiding or any other function.

Rolando


-----Original Message-----
From: marfig1970@... [ap-gto]
To: ap-gto
Sent: Sun, Aug 19, 2018 2:09 pm
Subject: [ap-gto] Some doubts about the use of the clutch knobs on the Mach1



I have some doubts about the correct use of the clutch knobs on the Mach1. Let me explain:

I have my mount located in my backyard on a semi-permanent basis (Park 3 position). When I have to take flats this is what I do:

(All this with the mount turned off)

- I release the clutch knobs and point my telescope at my LED panel.
- I tighten the clutch knobs again (I don't want any accidental movement).
- I take my flats.
- I release the clutch knobs and move the mount back to Park 3.
- I tighten the clutch knobs again.

Is this procedure okay or is it better to move the mount using my computer (or keypad)? I know I'm not going to damage anything, but I'm afraid it might affect the precise tracking or something.

Thank you,





Re: Saving SYNC/Rcal information

Stephane Charbonnel
 

Hi Ray,

Thank you for your reply.

For point 1/ sorry for APPM but it is APCC which calculate the model. In fact, there is no interaction between APPM and APCC only at the end of measures. So, I think it could be difficult to do a model better and better after each measure isn't it ?

For point 2 : I haven't think about PNT file. I could produce it. Thank you for idea.

Stephane


Le sam. 18 août 2018 à 17:56, 'Ray Gralak (Groups)' groups3@... [ap-gto] <ap-gto@...> a écrit :
 

Hi Stephane,

> Could APMM read such a file one day in order to make the pointing model.

Just to be clear, APPM does not create a model. APCC creates models from the data that APPM collects. APPM is a data point mapping utility.

> 2/ Each year, I bought Pinpoint only for APPM and I haven't SGP or so on. I use PRiSM. But I can produce TXT

If you are able to follow the format of a PNT file precisely then you should be able to construct a PNT file externally. Just strip existing and do not include the 4-digit CRC values on each line of the file you create. If APCC is running and you change it you will have to reload it into APCC each time it is changed.

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro V3: https://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: https://www.siriusimaging.com/apdriver

> -----Original Message-----
> From: ap-gto@... [mailto:ap-gto@...]
> Sent: Friday, August 17, 2018 4:02 AM
> To: ap-gto@...
> Subject: Re: [ap-gto] Saving SYNC/Rcal information
>
>
>
> Hello Ray,
>
> I use this topic to ask questions about pointing model of APPM :
>
> 1/ When I use my 10micron mount or when I had a Gemini system on Titan Losmandy, after the first 3 stars, I can
> see pointing model is refined after each pointing. So, pointing after pointing, the theorical coordinates become
> nearest apparent coordinates. I think it would be more practical and send less failure for some little fields as I have
> (I have a very little field of 7' x 7').
>
> 2/ Each year, I bought Pinpoint only for APPM and I haven't SGP or so on. I use PRiSM. But I can produce TXT
> files with a precision of fraction of arcsec with :
> * number of field
> * Theorical coordinates of center of field.
> * Apparent coordinates of center of field
> * Pier side of mount.
> Could APMM read such a file one day in order to make the pointing model (So I am aware in this cas e I cannot
> use the above point 1/ of my request ....).
>
> Regards
> Stephane
>
>
>


Re: What is the best process to recover a lost mount and check if there was any damage?

Roland Christen
 


I can resolve this with the help of our observatory manager and speaking to him over the phone! 
Just have your manager speak with someone here in AP support and I'm sure they can get things running again.

Rolando


-----Original Message-----
From: dhavalbrahmbhatt@... [ap-gto] <ap-gto@...>
To: ap-gto
Sent: Fri, Aug 17, 2018 11:08 pm
Subject: [ap-gto] What is the best process to recover a lost mount and check if there was any damage?



Sorry to keep coming back to the issue that I had about 10 days back - 

In essence, I had a PC failure and that caused all sorts of issues with my AP1200/CP3/APCC Pro. I basically "lost" all settings (I did restore them from back up, however -), I had to move the mount manually to to a Park 3 like position (obviously it was done manually so not sure if it was exactly Park 3 position or not) and as a result I lost the ability to Home the mount. In any case, after getting the mount to a Park 3 like position - I did a SYNC on the mount (not RCAL - I did initially try doing a RCAL, but it was too far off and it kept giving me an error message). At this point, I assumed everything was fine. I did not image for that night, but I did image the following night - no issues while I was imaging the first target. I was running a sequence through SGP and had at least 3 targets to shoot that night. However, after the first target was done, and when it was slewing to the second target, It did not complete slewing to the target. I wasn't looking at the mount at the time it was slewing and stopped slewing (this is in a remote observatory but I do have a camera in the observatory to "view" how things are going) - so I am not sure what exactly happened, however, when I viewed the mount on the camera in a bit (maybe a minute or so after when it was supposed to have slewed) I saw the mount was in a weird position - at the time, I believed it had come to a rest either because it hit something or it was at Horizon limit. Looking at the mount via the camera, it did not look like it had hit anything and the target that I had chosen was no where close to the Horizon limits that are set for my location - so I was truly surprised that the mount had ended up in the position that it was in. 

I obviously panicked and just hit Park in APCC Pro - the mount started going to a Park 3 position, just that, looking at it on the camera from 300 miles - it did not look like it was Park 3 (it was close, but not quite Park 3 - I could clearly tell by viewing the mount on the camera). The telescope was pointing West of the Meridian but the mount was pretty much pointing to Polaris (or thereabouts) with the CWs down. I left the mount in that position and let it be. We were not having clear nights over the past few days, so the mount was not touched. We did have a clear night tonight, so I tried to RCAL it tonight - but I just can't. Right now, the mount is not in one of its normal positions right now - meaning, not in a Park 3 position (I use Park 3, sorry, I haven't mentioned that before) nor anywhere close to it. 

I will have to have my observatory manager put it back in CW down, telescope facing Polaris position tomorrow morning and then figure out what's going on.

In the mean time - I have a few questions - 

1) Does anyone know what is going on with the mount? Why did it seem to work that one night after the initial "mount lost" episode, but upon slewing, it just went haywire?

2) With me being 300 miles away from the observatory, what is the best way to find out if there was any damage done to the mount during the first episode/slewing to the second target? I don't believe anything untoward did happen - I also had our observatory manager check for any physical damage to the mount, but he couldn't find any. I don't believe the worm or anything has been damaged - but is there a way I can find that out for sure?

3) Assuming everything is OK - what should my next steps be? I am guessing - after the observatory manager puts it back in CW down/scope facing Polaris position - I will run a pointing model and then try to Park it to Park 3. I will also set up a new HOME position and see if I can home the mount and then see if I can slew it to a few targets - do you think that this should re-orient the mount? Should I try to do something else?

I wish I could go out to the observatory, but I can't for the next couple weeks - so hopefully, I can resolve this with the help of our observatory manager and speaking to him over the phone! 

All help is greatly appreciated.

CS! 



Re: Triplet Lens -vs- Doublet Lens

Roland Christen
 



It is likely a triplet does a better job of correcting field curvature and other off axis issues but enough to count it out?
Filed curvature is a function of the focal length and has nothing to do with the number of elements if they are all in the same place up front. Typically the field curvature is around 1/3 of the focal length. There is also off-axis astigmatism which is similar in triplets and doublets. The only way around those two aberrations is to use a field flattener.

Rolando


-----Original Message-----
From: acf900gto@... [ap-gto]
To: ap-gto
Sent: Fri, Aug 17, 2018 5:56 pm
Subject: Re: [ap-gto] Triplet Lens -vs- Doublet Lens



The S2 and O3 filters would behave the same as the Ha.  Each would focus at a slightly different point but that happens anyway.   I believe the pixel scale would have an infinitesimal difference between the three masters.

I was specifically looking at a particular 152mm f/7.9 ED doublet as the basis for building a new scope.  Based on some of the published ray trace diagrams for lenses at this size and f/ratio, the RGB focuses are separated by about 1 mm.  This means you have a focal variation of 1mm in a 1200mm focal length.  I see a lot more focus spread than that from temperature variations when imaging with my 130mm f/6 APO.

Since a 152mm ED doublet lens is about $2,000 and a 152 ED triplet is about $6,000, it made me think about the real benefit of the triplet when considering NB imaging.  

It is likely a triplet does a better job of correcting field curvature and other off axis issues but enough to count it out?

With RGB imaging, the filter band passes are way bigger.  Probably enough to show problems but in NB, maybe not.  I guess all this could be tried with a smaller ED doublet refractor but I know there are optical engineers out there and was hoping for some feed back on the idea.  Or even info and pix from someone already doing this.

Charlie

 



Re: Triplet Lens -vs- Doublet Lens

Roland Christen
 


As we know, one of the benefits of a triplet lens is that it brings the three primary colors to a single focus while a doublet lens can only bring two of the primary colors to a common focus. 
This is not strictly true. A doublet lens can be constructed that brings more than 3 colors to a common focus. It requires special glasses that are more expensive than common ED combinations, but can be done.

An inexpensive ED doublet can do narrowband imaging quite nicely and can be as sharp if made properly.

Rolando


-----Original Message-----
From: acf900gto@... [ap-gto] <ap-gto@...>
To: ap-gto
Sent: Fri, Aug 17, 2018 12:46 pm
Subject: [ap-gto] Triplet Lens -vs- Doublet Lens



As we know, one of the benefits of a triplet lens is that it brings the three primary colors to a single focus while a doublet lens can only bring two of the primary colors to a common focus.  The third forms a kind of blur circle around the other two.

However, if I am doing narrow band imaging with something like a 5nm band pass Ha filter, I am only bringing a single "color" to a focus.  So, it would seem that it would be possible to do quality narrow band imaging with a good quality ED doublet lens.    A 6" ED doublet refractor is certainly a lot more affordable than a 6" ED triplet!

Is there any reason to believe an Ha image from a doublet would be of lower quality than an Ha image taken with a triplet?

Charlie




Re: First attempt at taking and correcting PE of new Mach1GTO

Stephen Winston
 

>I do have a planetary camera, asi120mc, which I can use if I reconfigure my main setup. Is this necessary?

You should see what results you get using 8300 with the updated version of PEMPro and when collecting more cycles.

In the end though, your sampling frequency of 4.5s is bigger than some of the errors you are trying to measure/correct (e.g. the 4s error mentioned earlier).  

If you want to get the best results you will want to sample at a higher rate (at least 2x) than the smallest error you want to correct (Nyquist says so ;)).  You can do this by either figuring out why the 8300 is taking 4.5s or trying a faster camera.


Re: Saving SYNC/Rcal information

Eduardo Oliveira
 

I think this explains a lot what I have been observing regarding pointing accuracy, which by the way is superb...only it doesn't seem to improve much with additional sync commands.

Eduardo.
 

Only the last Sync command is saved. The mount at this time does not accumulate the various errors and act on them later. Only the very last one is used for the next session.

Rolando


-----Original Message-----
From: eoliveira@... [ap-gto] <ap-gto@...>
To: ap-gto <ap-gto@...>
Sent: Wed, Aug 15, 2018 1:02 am
Subject: [ap-gto] Saving SYNC/Rcal information



Hi everyone,

I am sorry if this is answered somewhere else, but I could not find using Yahoo search engine. I am using APCC (standard version) and AP V2 Ascom driver with my Mach1 GTO CP4 mount. I use CdC and Astrophotography tools to point the telescope to targets. What I usually do is to send a Goto++ command in APT. This uses plate solve to iteratively put the telescope within X pixels of my target (X being the error threshold that I can configure to accept). When the target is at the center of the FOV I then issue a sync com mand which I presume will be translated into Rcal command to the controller since I have "Use Rcal for Syncs" option enabled at AP V2 Ascom driver. In a typical session I can issue between 3 to five sync commands for different targets or stars I use for focusing the scope. My question is: Do these sync commands improve the pointing accuracy of the mount on subsequent slews? Does this "pointing model" that is created with the multiple sync commands during one session remains available when I power down the mount and initiate a new session next day (assuming of course I did not loosened the clutches)? If it's not, can it be saved for future use?

Thank you all,

Eduardo




Re: Saving SYNC/Rcal information

Roland Christen
 


Do these sync commands improve the pointing accuracy of the mount on subsequent slews? Does this "pointing model" that is created with the multiple sync commands during one session remains available when I power down the mount and initiate a new session next day (assuming of course I did not loosened the clutches)? If it's not, can it be saved for future use?
Only the last Sync command is saved. The mount at this time does not accumulate the various errors and act on them later. Only the very last one is used for the next session.

Rolando


-----Original Message-----
From: eoliveira@... [ap-gto]
To: ap-gto
Sent: Wed, Aug 15, 2018 1:02 am
Subject: [ap-gto] Saving SYNC/Rcal information



Hi everyone,

I am sorry if this is answered somewhere else, but I could not find using Yahoo search engine. I am using APCC (standard version) and AP V2 Ascom driver with my Mach1 GTO CP4 mount. I use CdC and Astrophotography tools to point the telescope to targets. What I usually do is to send a Goto++ command in APT. This uses plate solve to iteratively put the telescope within X pixels of my target (X being the error threshold that I can configure to accept). When the target is at the center of the FOV I then issue a sync com mand which I presume will be translated into Rcal command to the controller since I have "Use Rcal for Syncs" option enabled at AP V2 Ascom driver. In a typical session I can issue between 3 to five sync commands for different targets or stars I use for focusing the scope. My question is: Do these sync commands improve the pointing accuracy of the mount on subsequent slews? Does this "pointing model" that is created with the multiple sync commands during one session remains available when I power down the mount and initiate a new session next day (assuming of course I did not loosened the clutches)? If it's not, can it be saved for future use?

Thank you all,

Eduardo




Re: [ap-ug] Re: Re: Astro-Physics now accepting 1100GTO orders again

Roland Christen
 

Hello Wade,

Just got back from a short trip.

Thanks for your suggestions. We are working on a lot of the things you mentioned, including the infamous "Sync" function among other things.

Rolando



-----Original Message-----
From: 'Wade Hilmo' y.groups@... [ap-ug]
To: ap-ug ; ap-gto
Sent: Tue, Aug 14, 2018 5:27 pm
Subject: RE: [ap-ug] Re: [ap-gto] Re: Astro-Physics now accepting 1100GTO orders again



It doesn’t look like a political statement to me.  It simply looks like a statement of fact.  I don’t infer anything about your political preferences from anything below.
 
For my part, I have worked extensively with many different mounts over the last 20 years.  I’ve owned about 10 mounts and have helped others to either use or troubleshoot their mounts.  The naysayers on Cloudy Nights are, for the most part, not owners of your products.  As someone who owns two of your mount and a handful of lower cost mounts, both built domestically and imported, the value in your products are obvious to me.  They are a pleasure to work with and in my opinion, are priced very reasonably for what you get.
 
That said, I had an interesting experience at a star party last week.  I was approached by a gentleman that I met last year at the same star party.  At that time, he bought an older Celestron mount from me.  He had a good experience with it, and decided that he wanted to try astrophotography.  To that end, he bought a used, 10 year old, Mach1 mount and brought it to this year’s star party having never used it (he powered it up at home and slewed it, but that was it).  When he got up to the site, he asked for my help to do a daytime polar alignment.
 
We we tried to do the daytime polar alignment, we were unable to do so because the mount stopped slewing to the next park position in mid-slew.  After a few minutes of troubleshooting, I noticed that there was a motor stall indication.  Further testing showed that it was specific to the declination drive.  I knew that it’s possible for the gear mesh to be affected by transport of the mount, and this star party does have a fair amount of washboard road in the last few miles up to the site.  But since I’ve never had it happen with my mounts (mine have the spring loaded gearboxes, so I wonder if they are more resilient), I wanted to talk to George before making mechanical adjustments to someone else’s mount (especially since they’d never even used it themselves and could tell me nothing of its history).  So I made the call, and George was professional and courteous (as has been everyone at Astro-Physics in the 5 years that I’ve been a customer).  He knew exactly what to do and relayed the instructions to me.  The cell phone coverage at the site was quite spotty, so I could not confirm with George that his suggestions worked perfectly, so I hope that he sees this.
 
Anyway, after adjusting the mesh, we tried to do the daytime polar alignment again.  Before doing the alignment, I wanted to sanity check that it would hit all 4 park positions.  So we started with the mount physically in Park 4 and selected new setup from the keypad and unparked from Park 4.  We then selected Park 3, and the mount went elsewhere.  After a bit more troubleshooting, I found that the location coordinates in the keypad were all zeros – even though the mount’s owner assured me that he’d set up the correct location and time.  After setting the location and time correctly for the site, we then completed the daytime polar alignment without further problems.  So I thought that we we were all set…
 
Later in the day, just before dusk, the mount owner came to find me again and said that the mount was broken again and would probably need to be serviced.  He claimed that the declination motor was not working anymore, even though the RA motor was working fine.  I went over there to find that he’d switched from the battery that we’d used for the alignment, over to a long DC cable connected to a different power source.  I had him show me what the mount was doing, and it was clear from listening to the RA motor, that it was not getting enough power.  I had him switch back to the originally battery that we’d used (and the stock power cable), and everything worked fine.  He kept using that battery and cord for the remainder of the star party and had no further problems.
 
The reason that I’ve relayed this story is that it was a bit of an eye opener to me, the things that users could do to get unexpected behavior from these mounts.  The owner of this mount is a smart guy, but had limited experience with astronomy and zero experience with imaging or running a mount from a computer (which was the reason for the questionable cabling and power supply above).  When we read about people having problems out on Cloudy Nights, it’s impossible for us to know what out-of-the-ordinary, or questionable, things that they’ve done in setting up or operating their mount.  Some things that seem obvious to me, like getting clean and stable power to all of the equipment in my imaging rig, aren’t given the same attention by everyone – and they are not likely to mention it when they describe their problems.
 
Even though I’ve done professional technical support in my distant past, I came away from the experience with a new appreciation for the level of service that you provide.
 
I would like to add some thoughts, though, as a user of many competing products.  It’s clear that some of the other mounts out there are getting better.  I don’t believe that they will ever match the quality of your products, but for the price, they beat the gear that I used to use pretty handily.  For lots of people, they might be “good enough”.
 
Personally, I love the fact that your mounts are flexible enough to do what I want to do with them, and they use engineering and execution to deliver top performance, as opposed to technical trickery (Did you know that it’s been discovered by users that the import mount that you refer to below cannot be autoguided when it’s doing periodic error correction, for some reason that the manufacturer had not disclosed?  This is the kind of arbitrary behavior that would drive me absolutely nuts as a user.)
 
That said, I believe that there is room for improvement in your controllers.  Using sync to determine which side is up seems to cause more than its share of problems.  Perhaps, it would be better to have sync just be a synonym for recalibrate and do the “true” sync only when unparking from one of the 4 built-in park positions.  If you want to continue supporting setting this without an unpark, perhaps you could create a new – and clearly named - function that does just this and put it somewhere under the setup menu.  Also, it would be nice to see some ability to deal with cone error.  My older Celestron mount can hit a goto target anywhere in the sky with my floppy mirrored SCT.  My AP mounts will get close, but benefit greatly from doing a recalibrate in each area of the sky that I work in.  My dream is that the CP4 controller has enough horsepower to do a full sky model (to compete with 10Micron) and that you will offer this someday.  But absent that, the ability to do 5 or 6 alignment stars to determine cone error would go a long way towards addressing that particular criticism.  Finally, it’s awesome that APCC can home a lost mount even without encoders, but this seems to be functionality that should be included in the ASCOM driver, and perhaps even the keypad.
 
Anyway, that’s just my feedback.  I hope you take it as constructive.
 
Thanks for offering a superior product.  And to anyone out there thinking about ordering an AP1100, just do it.  You will not regret it.
 
-Wade
 
 
 
From: ap-ug@... [mailto:ap-ug@...]
Sent: Monday, August 13, 2018 3:39 PM
To: ap-gto@...; ap-ug@...
Subject: [ap-ug] Re: [ap-gto] Re: Astro-Physics now accepting 1100GTO orders again
 



By the way, this is not a political position I'm taking as far as tariffs etc., something obviously has to be done about trade imbalance. It turns out that raw materials are being hit, but finished products such as scopes and mounts from China are not being affected by new tariffs. I am just relating the situation that we are dealing with at this time.
 
If you are on one side of the political spectrum, you can ask your congressman to help. If you are on the other side of the spectrum and think tariffs are great idea, then you can help by buying a US made product. It's all good!
 
Rolando
 
 
 
-----Original Message-----
From: chris1011@... [ap-gto] <ap-gto@...>
To: ap-gto <ap-gto@...>; ap-ug <ap-ug@...>
Sent: Mon, Aug 13, 2018 5:23 pm
Subject: [ap-gto] Re: Astro-Physics now accepting 1100GTO orders again
 
Hello All Astronuts,
 
I just want to remind you all that the new production has started and we are well under way to deliver these mounts later this Fall. If you wan to reserve one, please contact the office.
 
Some realities we've had to face are increased costs for raw materials. We use almost exclusively high grade aluminum billet and stainless steel in our mounts. Cost for these materials have now jumped 43% since the last production run. Some companies in our area, such as Harley Davidson, have bailed on manufacturing here and will be moving their production facilities out of the US. This will hurt a lot of the smaller companies which have been supplying them with castings, stampings and myriad other parts. We are not leaving! We are firmly committed to staying the course and have not raised our prices for the new production run, so you will be getting a good deal.
 
I am also quite aware that we are getting increased competition from overseas manufacturers and that they are getting better at making imaging mounts where precision tracking and guiding is important. Let me point out a couple advantages of our standard non-encoder 1100 mount that can't be matched by the newest low cost dual encoder import:
 
1) Our mount is based on the original old Shaefer mount, a time tested design that puts the Dec axis gearwheel as close to the RA as possible for ultimate stability (people in California know what I'm talking about). The closer the DEC is to the RA gearwheel, the more stable is the configuration and ability to transmit torque from the scope load down to the ground. It is fundamental mechanical engineering.
 
There are other ways to mount the Dec axis to the RA shaft, the worst of which is the "Goose neck" design which puts the RA gearwheel at the back of the mount and thus all torque must be transmitted from the Dec axis all the way down to the shaft before being transferred to the RA gearwheel teeth and ultimately to the ground. The long RA shaft acts as a torsion bar and can twist whenever torque is applied, thus stability suffers greatly. Thankfully these kinds of mounts are no longer being produced.
 
Now we have a Center Mounted type coming from the Orient where the Dec axis is on the RA shaft but still separated from the RA gearwheel by a torsion shaft. Whenever you have a torsion component in a system, it can twist, ever so slightly, to torque inputs. It acts like a spring and can have resonances. With just the right load the resonance can enhance and you can get some strange vibrations that don't damp out. This may occur during tracking but also during slewing. I'm a firm believer in the original Shaefer concept which actually goes back to Russel Porter (the designer of Mount Palomar 200"), and I don't see any advantage to center mount designs.

Bottom line - the 1100 is a very light weight mount that can hold a tremendous amount of load for imaging compared to its weight. For most people it is very portable, even when not split into two components. I'm a wimp and I can carry it easily and set it up on its pier.
 
2) Our 1100 mounts in the last production run have exhibited very low clean periodic error, even before PEM is applied. With PE applied the typical peak error has been under 1 arc sec P-P for a worm cycle with rms around 0.2 arc sec. The errors are very low for many worm cycles and in my tests both on the bench and under the night sky with instrument loads as large as 120lb, you can go 5 - 6 worm cycles (30 - 40 minutes) before you see any appreciable drift above 1 arc sec due to PE. Of course adding a Renishaw encoder will knock that down to zippo for those who want the ultimate accuracy. When it comes to actual tracking for long periods of time the basic 1100m mount is already more accurate than the challengers from the Orient with 2 encoders. Just because your mount has dual encoders does not mean it will track accurately over an extended time period.
 
3) The most important feature is the ability of our 1100 mount to start imaging with scope under the mount and proceed to track across the meridian all night without having to do a flip on a large portion of the sky. It means you can set the scope up under the mount early in the evening, to point at the object you want to image all night long. As long as the scope clears the pier, you are good to go and can go have dinner, watch a movie on TV, go to bed and wake up in the morning with lots of data. Never have to worry about whether the scope flipped at the meridian or not. You don't even need all the fancy software to control things if you want to keep it simple. In the morning the scope will point to the horizon or lower, but still clear the mount, even if you don't attend to it until noon. You can set a simple timer on your power supply and shut power off at dawn. You can get real fancy and control things with APCC, there are many safeguards that you can set if you want. Your choice to go as fancy or not as you want. No other mount lets you do that.
 
4) Finally, we do have clutches on all our mounts which you can choose for when you want to move the mount around manually for star hopping or setting up different scope configurations. We give you the choice, some of the other mounts do not. You can also lock down the clutches so your setup can't be disturbed by a stumble, that's your choice again.
 
In the end, look at all the features when choosing mounts, and you will see what a bargain the 1100 mount is.
 
Rolando
 
 
 






Re: Mach 1 Milestone – GearBox

Roland Christen
 

Please remember to disengage only when the mount is in Park3 position. That way even if the axes are out of balance they won't swing wildly. After balance, return the axes to Park3 and re-engage the gears.

Rolando



-----Original Message-----
From: keitholsen@... [ap-gto]
To: ap-gto
Sent: Tue, Aug 14, 2018 3:42 pm
Subject: [ap-gto] Re: Mach 1 Milestone – GearBox



I agree with you Darrell, it is a brilliant system.  Makes precise balancing a piece of cake!
Just remember to hold on to your counterweight shaft when disengaging the worm in case you are way out of balance(I know this first hand).



Re: 1100GTO not holding polar alignment

Joe Renzetti <axnyslie@...>
 

Thanks I will give a thorough examination to the Losmandy tripod and see is anything is moving. I'm always on pavement but usually extending one or two legs slightly to level the mount. The camera when attached to the Hyperstar is very stable I never have issues there. I'm still not sure if the RAPAS is aligned correctly. I've used the Polemaster a couple times and it's usually where it's aligned now. I wonder if it may be better to do the daytime flagpole alignment. I centered it on Polaris and when I moved the mount to Park 1 position Polaris moved off center slightly.

Joe

On Mon, Aug 20, 2018 at 2:35 AM, 'Joseph Zeglinski' J.Zeglinski@... [ap-gto] <ap-gto@...> wrote:
 

Joe,
 
    One other check – the Losmandy HD tripod head has “L-shaped slots“ for the  LT2APM adapter’s three mount attachment screws. Make sure that you give the seated mount a hard twist to lock it in,  after you drop it into the tripod, so that the three screws have slid to their extreme horizontal positions inside the three horizontal slot sections – and are not just sitting right under the insertion drop-in point (i.e. the vertical slot). Otherwise, the mount could shift up & down on one side, with slight changes in weight distribution during slews.
 
    If you haven’t done so, buy a set of those Losmandy Tripod Knobs (AP # LTKS) for the pier – they have a wider diameter grip surface onto the HD slot holes than AP’s screw heads, easier to tighten in the field, even with an Allan wrench (in later versions), if needed,   than the usual AP mount’s base screws which required a much thinner Allen wrench.
 
    When I used my AP-900,  carrying it to a field portable setup each time, setup was so much easier and quicker, if I left those three LTKS knobs “well-loosened”,  but still attached to the LT2APM. Didn’t need to keep threading in these tripod knobs every time - or worse, losing those original small AP mount base ring screws that they replaced.
 
Joe Z.
 



Re: 1100GTO not holding polar alignment

Joe Zeglinski
 

Joe,
 
    One other check – the Losmandy HD tripod head has “L-shaped slots“ for the  LT2APM adapter’s three mount attachment screws. Make sure that you give the seated mount a hard twist to lock it in,  after you drop it into the tripod, so that the three screws have slid to their extreme horizontal positions inside the three horizontal slot sections – and are not just sitting right under the insertion drop-in point (i.e. the vertical slot). Otherwise, the mount could shift up & down on one side, with slight changes in weight distribution during slews.
 
    If you haven’t done so, buy a set of those Losmandy Tripod Knobs (AP # LTKS) for the pier – they have a wider diameter grip surface onto the HD slot holes than AP’s screw heads, easier to tighten in the field, even with an Allan wrench (in later versions), if needed,   than the usual AP mount’s base screws which required a much thinner Allen wrench.
 
    When I used my AP-900,  carrying it to a field portable setup each time, setup was so much easier and quicker, if I left those three LTKS knobs “well-loosened”,  but still attached to the LT2APM. Didn’t need to keep threading in these tripod knobs every time - or worse, losing those original small AP mount base ring screws that they replaced.
 
Joe Z.
 


Re: 1100GTO not holding polar alignment

Joe Zeglinski
 

Joe,
 
    I’m not an expert, but ... a few thought.
 
    Have you routed your cables “through the AP-1100” and have you eliminated the possibility of “cable snag”? Maybe give them a bit of slack.
 
Losmandy HD Tripod:
    I noticed that you said your Losmandy legs are locked down, after any adjustment of their extension pipes. Did you check the tightness on both the upper locking knobs (i.e. tripod head attachment), as well as the lower set at the feet?
 
    I also use a standard Losmandy HD tripod for an RC-14 truss on my AP-1200, (OTA plus saddle etc., 74 lbs., similar to your C14 at 60 lbs.).
    But to make sure it would not slip,  ever so slightly, I cut three identical length wooden dowels (chop sticks, but can also use pencils, thick nails, etc. ), and inserted them right into those “leg slide” channels in the pipes, near the ground, to act as “stops” so that the leg extension won’t shift under all that weight - then locked the knobs there. This gave me an identical leg “extension” that can’t slip, even if those knobs loosened their grip. This could be a cause if the scope is set up quickly in the field each time.
    Since my Losmandy has leg extension lock knobs rather than lever handles, I used a “rubber strap wrench”,  for leverage to lock the knobs even harder than just by hand.
    Make sure that both the upper and lower leg lock knobs are very tight, since if they have become slightly loose, the Losmandy HD tripod head can shift a bit or wobble, depending on where the OTA slew ends.
 
CCD CAMERA:
    Could this be a camera attachment issue, with the CCD rotating, or sagging  slightly as the OTA angle changes during a slew? Give it a gentle hand twist to see if it is indeed firmly seated in the draw tube, if using an eyepiece adapter. If the CCD is threaded onto an adapter, make sure it isn’t “unscrewing itself” due to the weight of the camera. This is often a problem with a CCD whose centre of gravity is offset – like the overhang on an STL-11000, especially with an of axis guider or filter wheel.
 
    Since the drift seems to happen right after even a short slew ... What planetarium software are you using? Could it be that it is correcting differently for year J2000 coordinates than the APCC?
 
Joe Z.


Re: 1100GTO not holding polar alignment

Christopher Erickson
 

Either something is assembled incorrectly or your pier/tripod/ground has something going on.

What kind of ground?

What kind of pier/tripod?

Maybe grab the mount head and try to wiggle it around a bit.  Where does any flexure take place?


On Sun, Aug 19, 2018 at 5:27 PM Joe Renzetti axnyslie@... [ap-gto] <ap-gto@...> wrote:
Well I’m still trying to resolve this problem with no luck and it seems to be getting worse. Both the alt and az moves significantly when slewing and not even that far, like 20 degrees. No matter how much I tighten it down with Allen wrenches it won’t hold. Plus tonight it was drifting quite a bit. I was only doing 60 second subs and the stars are decent but within 30 minutes the target moved off center quite a bit. Plus I had several oscillation errors. Can’t say I’m happy at all now I expect a lot better from a premium mount and this is sub par performance for sure.

Joe

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Posted by: Joe Renzetti <axnyslie@...>
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Re: First attempt at taking and correcting PE of new Mach1GTO

Cheng-Yang Tan
 

Download from STF8300 is about 1s. I focus with 1/2 to 1s integration time and it takes 1s to do a full frame download. Definitely not 4 s.

I do have a planetary camera, asi120mc, which I can use if I reconfigure my main setup. Is this necessary?

On Sunday, August 19, 2018, 11:27 PM, stephenjwinston@... [ap-gto] wrote:

 



>That's the total time it took for PHD2 to download and calculate the centroid and send an event to PEMPro. 
>I'm not sure why the camera would take that long unless it was always exposing/downloading a full 
>exposure instead of a sub frame.
 
Full frame download on the STF-8300 is supposed to be around 1s, so 4.5s still seems slow.  

For comparison, on my STi with a PHD2 sample rate of 1s I get a sampling rate of 1.2s in PEMPro, so around 0.2s for PHD2 overhead + download time.

Cytan - how long does full frame download from the 8300 normally take on your system?  And do you maybe have a faster / lower-resolution guide camera you could use instead?


Re: 1100GTO not holding polar alignment

Dale Ghent
 

On Aug 19, 2018, at 11:27 PM, Joe Renzetti axnyslie@... [ap-gto] <ap-gto@...> wrote:

Well I’m still trying to resolve this problem with no luck and it seems to be getting worse. Both the alt and az moves significantly when slewing and not even that far, like 20 degrees. No matter how much I tighten it down with Allen wrenches it won’t hold. Plus tonight it was drifting quite a bit. I was only doing 60 second subs and the stars are decent but within 30 minutes the target moved off center quite a bit. Plus I had several oscillation errors. Can’t say I’m happy at all now I expect a lot better from a premium mount and this is sub par performance for sure.
At this point, the obligatory question must be asked: Have you contacted support@... about this?

/dale


Re: First attempt at taking and correcting PE of new Mach1GTO

Stephen Winston
 



>That's the total time it took for PHD2 to download and calculate the centroid and send an event to PEMPro. 
>I'm not sure why the camera would take that long unless it was always exposing/downloading a full 
>exposure instead of a sub frame.
 
Full frame download on the STF-8300 is supposed to be around 1s, so 4.5s still seems slow.  

For comparison, on my STi with a PHD2 sample rate of 1s I get a sampling rate of 1.2s in PEMPro, so around 0.2s for PHD2 overhead + download time.

Cytan - how long does full frame download from the 8300 normally take on your system?  And do you maybe have a faster / lower-resolution guide camera you could use instead?


Re: 1100GTO not holding polar alignment

Joe Renzetti <axnyslie@...>
 

Well I’m still trying to resolve this problem with no luck and it seems to be getting worse. Both the alt and az moves significantly when slewing and not even that far, like 20 degrees. No matter how much I tighten it down with Allen wrenches it won’t hold. Plus tonight it was drifting quite a bit. I was only doing 60 second subs and the stars are decent but within 30 minutes the target moved off center quite a bit. Plus I had several oscillation errors. Can’t say I’m happy at all now I expect a lot better from a premium mount and this is sub par performance for sure.

Joe


Re: First attempt at taking and correcting PE of new Mach1GTO

Ray Gralak
 

Cytan,

Although you can get away with 3.5 cycles, I highly recommend that you do at least 5-6 cycles. The longer duration will increase resolution of the fitted curve that PEMPro will create.

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro V3: https://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: https://www.siriusimaging.com/apdriver

-----Original Message-----
From: ap-gto@... [mailto:ap-gto@...]
Sent: Sunday, August 19, 2018 7:12 PM
To: ap-gto@...
Subject: Re: [ap-gto] Re: First attempt at taking and correcting PE of new Mach1GTO



Yes, it's 3.5 cycles. I meant that the AP document

http://www.astro-physics.com/tech_support/mounts/Making_PE_Curve.pdf


says to do 3 and not 6.

I plan to do it again on with the updated PemPro the next clear night.

cytan


On Sunday, August 19, 2018, 9:07:32 PM CDT, stephenjwinston@... [ap-gto] <ap-
gto@...> wrote:




Hi Cytan,


Your PHD2 logs do indeed show a sampling rate of 1s, not the 4.5s shown in the PEMPro log - not sure why that is
or if it is fixed o the new version of PEMPro Ray created.

The PHD2 logs do only show 3.5 cycles of captured data (28 minutes worth). What made you think yo were getting
6 cycles?

And BTW: the final PE seen in the GA run you did at the end of the night looks pretty good and seems to match your
measured 1.5 arc-s.

Maybe Ray can clarify, but not clear what the impact of this incorrect tag that Ray fixed is - ig it was putting your
PEC curve completely out of sync I'd be surprised that yuo ened up with 1.5 arc/s as the corrected result.

Anyway, seems that you should redo the measurements and PE creation using the updated version of PEMPro and
see if it improves.&nbs p;

Steve


Re: First attempt at taking and correcting PE of new Mach1GTO

Ray Gralak
 

Hi Steve,

Your PHD2 logs do indeed show a sampling rate of 1s,
The 1 second is just the duration between exposures after an exposure is done.

not the 4.5s shown in the PEMPro log -
That's the total time it took for PHD2 to download and calculate the centroid and send an event to PEMPro. I'm not sure why the camera would take that long unless it was always exposing/downloading a full exposure instead of a sub frame.

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro V3: https://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: https://www.siriusimaging.com/apdriver


-----Original Message-----
From: ap-gto@... [mailto:ap-gto@...]
Sent: Sunday, August 19, 2018 7:07 PM
To: ap-gto@...
Subject: Re: [ap-gto] Re: First attempt at taking and correcting PE of new Mach1GTO



Hi Cytan,

Your PHD2 logs do indeed show a sampling rate of 1s, not the 4.5s shown in the PEMPro log - not sure why that is
or if it is fixed o the new version of PEMPro Ray created.

The PHD2 logs do only show 3.5 cycles of captured data (28 minutes worth). What made you think yo were getting
6 cycles?

And BTW: the final PE seen in the GA run you did at the end of the night looks pretty good and seems to match your
measured 1.5 arc-s.

Maybe Ray can clarify, but not clear what the impact of this incorrect tag that Ray fixed is - ig it was putting your
PEC curve completely out of sync I'd be surprised that yuo ened up with 1.5 arc/s as the corrected result.

Anyway, seems that you should redo the measurements and PE creation using the updated version of PEMPro and
see if it improves.

Steve