Date   

Guiding moving in dec

PeterN
 

I have had my first few imaging runs with my AP1200 and Planewave 12.5. The camera is an ST8XE and I am using MaxIm DL V5 to control it. I have the telescope pretty well balanced, although it is slightly heavy on the camera end since adding cables etc. I have a slide weight on the top slide rail of the scope to do fine balance. What I notice is the scope has a tendency to move Nth slightly. If I am guiding, the dec graph curve in MaxIm has a slight downhill slope, then jumps up after awhile to correct, giving a "saw tooth" type graph. Is this a balance problem? Should I try and balance the scope perfectly by sliding in the dovetail and do away with the top sliding weight?
Thanks
Peter


Re: [ap-ug] Pulsating Variable Star CY Aqr

Charlie Miller <cmiller@...>
 

Sean:

SBIG's CCDSoft v5 has complete support for doing photometry.

You can get a quick overview here:

http://www.bisque.com/help/CCDSoft/afxcore/determining_stellar_magnitudes.htm

or download the CCDSoft manual:

http://www.bisque.com/help/ccdsoft%20info/ccdsoft_version_5_user_s_manual.htm

cm

On 8/28/2010 6:34 PM, Sean Curry wrote:

Anthony,

I found this very interesting - thanks for sharing.

Do you have any more details on your data processing tools and techniques?

Thanks,

Sean

On Thu, Aug 26, 2010 at 5:50 PM, Anthony Ayiomamitis
<anthony@... <mailto:anthony%40perseus.gr>>wrote:




Gents,

I was trying to come up with some work for myself last night given the
effectively full moon would be a nuisance with its lighting up of the
sky during the whole evening. I remembered a project which I had
started
a few years ago on high-amplitude short-period pulsating variables of
type SX-Phe. A quick browse through my cheat notes immediately
yielded a
perfectly placed candidate, namely CY Aqr.

Within minutes of setting up I discovered that the moon was
literally on
the eastern border of CY Aqr. Looking for a very desperate photon
fix, I
went ahead anyway and took a peek at the first 30 minutes worth of
data
to see if my Baader infrared filter could do its magic once again
given
the huge and nearby obstacle named Luna. There was no question I was
recording the variability of CY Aqr and as indicated by another
check 30
minutes thereafter.

I let everything do its thing for nearly six hours and I only stopped
when the roof of the house became an obstacle at 4:00 AM.

What does CY Aqr do every 88 minutes? Here is the answer on this
active
pulsating variable:
http://www.perseus.gr/Astro-Photometry-Aqr-CY-20100825.htm .

I have a similar problem for this evening involving Luna and I
will see
if I can identify an exoplanet which I have yet to visit and which
transits this evening. If not, I will locate another similar SX-Phe
variable.

Anthony.

------------------------------------

[Non-text portions of this message have been removed]


High-Amplitude Short-Period Pulsating Var XX Cyg

Anthony Ayiomamitis <anthony@...>
 

Dear group,

Last night I went after the high-amplitude short-period pulsating variable XX Cyg which was foirst discovered in 1904 and various studies since then have suggested of a slight trend over time involving a small increase in the period.

For last night's result based on just under 8 hrs, please see http://www.perseus.gr/Astro-Photometry-Cyg-XX-20100828.htm . There is some very slight degradation in the quality of the data at the end of the time series due to the low altitude of XX Cyg at the time.

Tonight's menu involves an exoplanet transit involving a very fresh find and which was announced just a few days ago.

Anthony.


Re: [ap-ug] Pulsating Variable Star CY Aqr

Anthony Ayiomamitis <anthony@...>
 

Hi Sean,

I am delighted to learn you found the result of interest. I have another gem in progress right now (XX Cyg) and a quick browse at the intermediate data after 5 hrs looks excellent.

The work is standard photometry and I am not sure if there is any sort of advice I can provide. The trick is to get good SNR and to be careful not to saturate any pixel given the magnitude fluctuations. Also, if using an ABG camera, make sure you work within the linear response portion so as to have good useable data. As always, make sure you perform complete reduction (bias, darks, flats, flat-darks).

I would love to help further but I do not know how.

Anthony.

O/H Sean Curry έγραψε:


Anthony,

I found this very interesting - thanks for sharing.

Do you have any more details on your data processing tools and techniques?

Thanks,

Sean

On Thu, Aug 26, 2010 at 5:50 PM, Anthony Ayiomamitis <anthony@... <mailto:anthony%40perseus.gr>>wrote:




Gents,

I was trying to come up with some work for myself last night given the
effectively full moon would be a nuisance with its lighting up of the
sky during the whole evening. I remembered a project which I had
started
a few years ago on high-amplitude short-period pulsating variables of
type SX-Phe. A quick browse through my cheat notes immediately
yielded a
perfectly placed candidate, namely CY Aqr.

Within minutes of setting up I discovered that the moon was
literally on
the eastern border of CY Aqr. Looking for a very desperate photon
fix, I
went ahead anyway and took a peek at the first 30 minutes worth of
data
to see if my Baader infrared filter could do its magic once again
given
the huge and nearby obstacle named Luna. There was no question I was
recording the variability of CY Aqr and as indicated by another
check 30
minutes thereafter.

I let everything do its thing for nearly six hours and I only stopped
when the roof of the house became an obstacle at 4:00 AM.

What does CY Aqr do every 88 minutes? Here is the answer on this
active
pulsating variable:
http://www.perseus.gr/Astro-Photometry-Aqr-CY-20100825.htm .

I have a similar problem for this evening involving Luna and I
will see
if I can identify an exoplanet which I have yet to visit and which
transits this evening. If not, I will locate another similar SX-Phe
variable.

Anthony.

------------------------------------


Re: [ap-ug] Pulsating Variable Star CY Aqr

Sean Curry <sxcurry@...>
 

Anthony,

I found this very interesting - thanks for sharing.

Do you have any more details on your data processing tools and techniques?

Thanks,

Sean

On Thu, Aug 26, 2010 at 5:50 PM, Anthony Ayiomamitis <anthony@...>wrote:




Gents,

I was trying to come up with some work for myself last night given the
effectively full moon would be a nuisance with its lighting up of the
sky during the whole evening. I remembered a project which I had started
a few years ago on high-amplitude short-period pulsating variables of
type SX-Phe. A quick browse through my cheat notes immediately yielded a
perfectly placed candidate, namely CY Aqr.

Within minutes of setting up I discovered that the moon was literally on
the eastern border of CY Aqr. Looking for a very desperate photon fix, I
went ahead anyway and took a peek at the first 30 minutes worth of data
to see if my Baader infrared filter could do its magic once again given
the huge and nearby obstacle named Luna. There was no question I was
recording the variability of CY Aqr and as indicated by another check 30
minutes thereafter.

I let everything do its thing for nearly six hours and I only stopped
when the roof of the house became an obstacle at 4:00 AM.

What does CY Aqr do every 88 minutes? Here is the answer on this active
pulsating variable:
http://www.perseus.gr/Astro-Photometry-Aqr-CY-20100825.htm .

I have a similar problem for this evening involving Luna and I will see
if I can identify an exoplanet which I have yet to visit and which
transits this evening. If not, I will locate another similar SX-Phe
variable.

Anthony.

------------------------------------


[Non-text portions of this message have been removed]


Re: SmartGuide compatible with lunar tracking (hand keypad v4.17) ?

christian viladrich
 

Dear All,

I would like to confirm a small issue I had encountered some times ago trying to use the "smartguide" function of the Keypad to improve on the lunar tracking.

Here is the description of the problem :

First, the objective is to track the moon motion in alpha and delta over a long time period (10-15 mn) for high resolution (and narrow field) imaging (Celestron 14 at 8 m focal lenght with Skynyx 2.1 camera):
http://astrosurf.com/viladrich/astro/moon/closeup/closeup.html

So I used the "smartguide" function to improve on the "lunar speed" provided by the hand keypad and tune finely onthe lunar motion (in both alpha and delta).


First way to do it :
- the tracking speed of the keypad was set on "sideral"
- I entered the "smartguide" function of the hand keypad,
- centered a crater on the moon for about 3 mn,
- the keypad gave the speed values :
Right ascension speed = 0.34 arcsec / s (the correct value would be 0.5 arcsec / s, but the polar alignment was probably not perfect),
Dec speed = 0.20 arcsec / s (this value is correct)
Time = 176 s
Speed = X 0.25

- when I hit GOTO to start the "SmartGuide running", I had:
RM = 90 ms
DM = 50 ms
PE = 1000 ms
Speed = 0.25 X
- then the tracking of the moon was close to good, though a bit bumpy because the "base speed" was set on "sideral speed".

Second way to do it :

- the tracking speed of the keypad was set on "lunar". Then, it was far easier to perform the whole calibration process than using the "sideral" speed. There is only a 0.5 arcsec / s speed difference between sideral and lunar tracking, but this is a huge difference when you are imaging at 8 m focal lenght with 4.5 micron pixels ;-)
- I centered a crater on the moon for about 2 mn,
- the keypad gave the speed values :
Right ascension speed = 0.25 arcsec / s,
Dec speed = 0.21 arcsec / s (correct value)
Time = 119 s
Speed = X 0.25

- when I hit GOTO to start the "SmartGuide running", I had:
RM = 65 ms
DM = 55 ms
PE = 1000 ms
Speed = 0.25 X
- this time the tracking on the moon was really bad in alpha (overcorrection), but still good in delta.

So I suspect the "smartguide" function of the keypad assumes the tracking speed is set on "sideral" and not on lunar.

If this analysis is confirmed, would it be possible to correct this. Indeed, using "lunar" speed as a "base" speed would reduce the number of corrections and would give a smoother tracking, which is important for high resolution imaging.

PS : I can possibly make some more tests in the coming nights if it helps.

Best regards

Christian Viladrich






Le 24/03/2010 20:26, chris1011@... a crit :


In a message dated 3/24/2010 5:37:05 AM Central Daylight Time,
christian.viladrich@... writes:


So I am wondering whether SmartGuide assumes the mount is tracking at
sideral speed when doing the measurement ?
Smart Guide tracks at whatever rate you set on the keypad. There are two
parts to the guiding, the duration of the pulse (pulse width) and the timing
of the pulse (pulse repetition rate).

You can set those motions manually. For instance, if you set the duration
to 50 milliseconds and the timing to 1 second, the program will "push the
button" so to speak, for 0.05 seconds every second. This translates to a motion
of 0.75 arc seconds per second at 1x sidereal, or half that at .5x and one
quarter that at .25x. If you want to cut those rates in half again, you can
simply dial in a 2 second timing of the pulse, (or you can keep the 1 second
time and dial in 25 millisec pulse width).

When you use the automatic mode, you first have to specify the timing. If
you set that too fast, and the drift is too slow, it may end up that the
program cannot produce a short enough pulse to satisfy the overall slow drift.
Therefore you need to try a much longer time interval when the pulse is
applied.

Rolando





------------------------------------

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Re: Help with choice.

sforster12
 

Thanks for all your input.

I'll wait for the 1200 in 2011, which will coincide with partial retirement.

STU

--- In ap-gto@..., "MarkK" <MailYahoo@...> wrote:

I have had a lot more on the AP1200 for imaging

Personally have always had issues with a side by side mounting

Over under is the way I would go and never try side by side again-

Always had issues with guiding over 8 min when I went side by side could never get it to work out correctly





MarkK









On Aug 26, 2010, at 5:37 PM, "sforster12" <SHFORSTER1@... <mailto:SHFORSTER1%40aol.com> > wrote:

I'm on the list for an AP 1200, which I hope will arrive in the spring of 2011.
My primary imaging scope is a Deep Sky Instruments 10 RC, which weighs about 40 pounds with an STL camera.
I also image with a TMB 175 CNC tube scope which probably weighs 60 pounds with camera.
I was hoping to mount these side by side on the AP 1200.
Will this tax the mount too much?

I'm trying to not jump to a 3600, but I don't want to shoot myself in the foot going too small.

Thanks for any input.

STU









Re: amber light at startup

Joe Zeglinski
 

Hi,

This problem with the power cord happens so often, for others, that I got in the habit of routing the power cord and also the handpad - UP & closely AROUND the Y-Cable connector on the panel, and then passed down, in-between the connector and the shorter cable loop going to the RA motor. The hefty Lemo panel connector provides some "lift" at the crucial ends of the DC & pad cables, and they will not drop off this make shift support, since they are passed through a loop. The mass of the coiled pad cable, and the noise filter on the DC cable , add far too much weight on those connectors, and can cause intermittent signalling.

The DC cable is particularly bad, since it not only hangs straight down or worse, could get stomped on and pulled. It also takes a really bad, sharp 180 degree bend, right off the top of its connector. I'm surprised it doesn't get tugged right out of is housing, if you trip over the power cable in the dark. These two cables definitely need better support and especially restraint.

My method of relieving the strain on those two cables, seems to work fine for me. An alternative, in the panel, would be to add a standoff post to the DEC cable plastic clip, where these two cables could be even better restrained, or at the very least, purchase an additional "two cable diameter" clip, and screw down both nylon clips to the same place.
Likely, any of these three methods should be equally effective.

HTH
Joe Z.

----- Original Message -----
From: "behyar1" <behyar@...>
To: <ap-gto@...>
Sent: Friday, August 27, 2010 7:22 PM
Subject: [ap-gto] Re: amber light at startup


On my AP900 I had a problem where I would get the orange light sometimes if I touched the power connector at the control pannel end after it was screwed in. I had to unscrew it a little before it would go back to Red.

When I called into AP, they told me to take a small flat screw driver and expand the split center pin of the power connector (on the control panel). That did the trick for me.

Behyar

--- In ap-gto@..., jbu800@... wrote:

When I first turn on the Mach1 I sometimes get an amber (orange) light on the GTO control panel, but not always. The moment I select my location on the keypad the light turns to red and all seems to function normally. Has anyone else experienced this? and what is causing it? Could it be an indication of some more serious issue?



------------------------------------

To UNSUBSCRIBE, or for general information on the ap-gto list
see http://groups.yahoo.com/group/ap-gtoYahoo! Groups Links



Re: amber light at startup

Behyar Bakhshandeh
 

On my AP900 I had a problem where I would get the orange light sometimes if I touched the power connector at the control pannel end after it was screwed in. I had to unscrew it a little before it would go back to Red.

When I called into AP, they told me to take a small flat screw driver and expand the split center pin of the power connector (on the control panel). That did the trick for me.

Behyar

--- In ap-gto@..., jbu800@... wrote:

When I first turn on the Mach1 I sometimes get an amber (orange) light on the GTO control panel, but not always. The moment I select my location on the keypad the light turns to red and all seems to function normally. Has anyone else experienced this? and what is causing it? Could it be an indication of some more serious issue?


Re: amber light at startup

Jeffrey A. Steinberg
 

What is your power source and are you sure the cigarette lighter plug is in all the way?

-----------------
Jeffrey Steinberg
914-374-7503

On Aug 27, 2010, at 7:48 AM, jbu800@... wrote:

When I first turn on the Mach1 I sometimes get an amber (orange) light on the GTO control panel, but not always. The moment I select my location on the keypad the light turns to red and all seems to function normally. Has anyone else experienced this? and what is causing it? Could it be an indication of some more serious issue?


Re: 3600GTO- now accepting orders for delivery this Fall

Jeffrey A. Steinberg
 

Mounts are a function of CNC machining capability and assembly throuput. Scopes are a function of Roland throughput. No way to scale him and keep quality the same.

-----------------
Jeffrey Steinberg
914-374-7503

On Aug 26, 2010, at 12:42 PM, michael mcdermott <classicstone9474@...> wrote:

I am hoping the production on your telescopes take a turn for the better, with much improved turn-around on mounts within the last few years!

--- On Wed, 8/25/10, Marj <marj@...> wrote:

From: Marj <marj@...>
Subject: [ap-gto] 3600GTO- now accepting orders for delivery this Fall
To: ap-gto@...
Cc: ap-ug@...
Date: Wednesday, August 25, 2010, 9:58 PM



On August 19, we began our notifcation process for "el Capitan" our
largest mount by notifying all people on the list. Today, we opened up
the order process to anyone who would like to order this mount. Most of
the parts have been machined and we have started assembly. We anticipate
that the first orders will ship in October.

If you have a large instrument or wish to mount multiple instruments
side-by-side, you may wish to consider the 3600GTO. Check out the
website for further details.
http://www.astro-physics.com/products/mounts/3600gto/3600gto.htm

Note that we now have a 27" Dovetail Sliding Bar that is perfect for
side-by-side arrangements.

Clear Skies!

Marj Christen
Vice President
Astro-Physics, Inc
11250 Forest Hills Road
Machesney Park, IL 61115
Phone: 815-282-1513
Fax: 815-282-9847
www.astro-physics.com
Please include this e-mail with your response.

[Non-text portions of this message have been removed]




amber light at startup

jbu800@...
 

When I first turn on the Mach1 I sometimes get an amber (orange) light on the GTO control panel, but not always. The moment I select my location on the keypad the light turns to red and all seems to function normally. Has anyone else experienced this? and what is causing it? Could it be an indication of some more serious issue?


Re: [ap-ug] Pulsating Variable Star CY Aqr

Anthony Ayiomamitis <anthony@...>
 

Pete,

Glad to learn it is of interest and especially that it is of educational value. The latter is very important to me and I do favour such projects and results.

You mention North Florida weather. I spent three years in Jacksonville and know the tempermental nature of the local weather there quite well.

Anthony.

O/H p14@... έγραψε:


Anthony,

Great work and good to see you have some clear sky to work with. My sky in North Florida has been either too cloudy or turbulent lately.

Your apogee/perigee Moon images are fun to start discussions with the kids/people about the dynamics of our local universe.

Take Care,

Pete
----- Original Message -----
From: "Anthony Ayiomamitis" <anthony@... <mailto:anthony%40perseus.gr>>
To: ap-ug@... <mailto:ap-ug%40yahoogroups.com>, ap-gto@... <mailto:ap-gto%40yahoogroups.com>
Sent: Thursday, August 26, 2010 8:33:09 AM
Subject: [ap-ug] Pulsating Variable Star CY Aqr

Gents,

I was trying to come up with some work for myself last night given the
effectively full moon would be a nuisance with its lighting up of the
sky during the whole evening. I remembered a project which I had started
a few years ago on high-amplitude short-period pulsating variables of
type SX-Phe. A quick browse through my cheat notes immediately yielded a
perfectly placed candidate, namely CY Aqr.

Within minutes of setting up I discovered that the moon was literally on
the eastern border of CY Aqr. Looking for a very desperate photon fix, I
went ahead anyway and took a peek at the first 30 minutes worth of data
to see if my Baader infrared filter could do its magic once again given
the huge and nearby obstacle named Luna. There was no question I was
recording the variability of CY Aqr and as indicated by another check 30
minutes thereafter.

I let everything do its thing for nearly six hours and I only stopped
when the roof of the house became an obstacle at 4:00 AM.

What does CY Aqr do every 88 minutes? Here is the answer on this active
pulsating variable:
http://www.perseus.gr/Astro-Photometry-Aqr-CY-20100825.htm .

I have a similar problem for this evening involving Luna and I will see
if I can identify an exoplanet which I have yet to visit and which
transits this evening. If not, I will locate another similar SX-Phe
variable.

Anthony.

------------------------------------


Re: Help with choice.

MailYahoo
 

I have had a lot more on the AP1200 for imaging

Personally have always had issues with a side by side mounting

Over under is the way I would go and never try side by side again-

Always had issues with guiding over 8 min when I went side by side could never get it to work out correctly





MarkK

On Aug 26, 2010, at 5:37 PM, "sforster12" <SHFORSTER1@... <mailto:SHFORSTER1%40aol.com> > wrote:

I'm on the list for an AP 1200, which I hope will arrive in the spring of 2011.
My primary imaging scope is a Deep Sky Instruments 10 RC, which weighs about 40 pounds with an STL camera.
I also image with a TMB 175 CNC tube scope which probably weighs 60 pounds with camera.
I was hoping to mount these side by side on the AP 1200.
Will this tax the mount too much?

I'm trying to not jump to a 3600, but I don't want to shoot myself in the foot going too small.

Thanks for any input.

STU


Re: Help with choice.

Jeffrey A. Steinberg
 

Good to go! Have at it.

-----------------
Jeffrey Steinberg
914-374-7503

On Aug 26, 2010, at 5:37 PM, "sforster12" <SHFORSTER1@...> wrote:

I'm on the list for an AP 1200, which I hope will arrive in the spring of 2011.
My primary imaging scope is a Deep Sky Instruments 10 RC, which weighs about 40 pounds with an STL camera.
I also image with a TMB 175 CNC tube scope which probably weighs 60 pounds with camera.
I was hoping to mount these side by side on the AP 1200.
Will this tax the mount too much?

I'm trying to not jump to a 3600, but I don't want to shoot myself in the foot going too small.

Thanks for any input.

STU


[Non-text portions of this message have been removed]


Re: Help with choice.

Kent Kirkley
 

No problem....it won't even breath hard. :))


Kent Kirkley

-----Original Message-----
From: sforster12 <SHFORSTER1@...>
To: ap-gto@...
Sent: Thu, Aug 26, 2010 4:37 pm
Subject: [ap-gto] Help with choice.


I'm on the list for an AP 1200, which I hope will arrive in the spring of 2011.
My primary imaging scope is a Deep Sky Instruments 10 RC, which weighs about 40
pounds with an STL camera.
I also image with a TMB 175 CNC tube scope which probably weighs 60 pounds with
camera.
I was hoping to mount these side by side on the AP 1200.
Will this tax the mount too much?

I'm trying to not jump to a 3600, but I don't want to shoot myself in the foot
going too small.

Thanks for any input.

STU



------------------------------------

To UNSUBSCRIBE, or for general information on the ap-gto list
see http://groups.yahoo.com/group/ap-gtoYahoo! Groups Links


Help with choice.

sforster12
 

I'm on the list for an AP 1200, which I hope will arrive in the spring of 2011.
My primary imaging scope is a Deep Sky Instruments 10 RC, which weighs about 40 pounds with an STL camera.
I also image with a TMB 175 CNC tube scope which probably weighs 60 pounds with camera.
I was hoping to mount these side by side on the AP 1200.
Will this tax the mount too much?

I'm trying to not jump to a 3600, but I don't want to shoot myself in the foot going too small.

Thanks for any input.

STU


Re: Sensitivity to non-orthogonal imaging gear on AP900

CurtisC <calypte@...>
 

The question was directed to Rolando (who answered), but thank you for the update on your Meade. The best views I saw of Mars in 2003 were through a Meade 14. I have a 10, and I haven't been able to get good CCD images through it, even though it's been quite good visually.

--- In ap-gto@..., michael mcdermott <classicstone9474@...> wrote:

No I have not, I very happy with my Meade 14". So no need to waste money to compare.- Mike

--- On Wed, 8/25/10, CurtisC <calypte@...> wrote:


From: CurtisC <calypte@...>
Subject: [ap-gto] Re: Sensitivity to non-orthogonal imaging gear on AP900
To: ap-gto@...
Date: Wednesday, August 25, 2010, 9:46 PM


 



Have you had a chance to try the newer Meade & Celestron scopes, the ACF & EdgeHD?

--- In ap-gto@..., chris1011@ wrote:

In a message dated 8/25/2010 8:39:01 PM Central Daylight Time,
wildwood7711@ writes:


I have an AP1200GTO with a Meade 14" (3556mm) SCT, my scope is not
orthogonal to the mount but I am dead on polar aligned. I have tried all of
Rolands methods (I have a permanent pier). I have used the polar alignment
wizard in PEMpro as well. I also fine tuned it using a 9mm cross-haired eyepiece
with drift aligned. I can without using a guide scope with a 2x barlow and
take up to 200 frames of 2 minutes each and the object is still on my
computer screen. The only way I see an orthogonal issue if I merdian flip. The
object is lost and I must use a 40 mm eyepiece to be able to see the object
again requiring recentering it and selecting RECAL on the handbox. The
mount is great, my orthogonal of my telescope to the mount isnt.Too big of a
hassle to try and shim the telescope to make it so. And really, who needs
it!
I have a 10" Meade which I have used on both a Mach1 and a 900 mount.
Although the scope itself is fairly orthogonal, the optics don't stay put. The
image shifts when I go from east to west due to mirror flop. This occurs even
with the mirror locked down. So even if I tried shimming, the scope still
won't stay orthogonal.

Rolando












Mach1-planning

Marco Meiling <marco.meiling@...>
 

I love the improvement in your mounts-department.
A good mount improves every scope you put on it.
So it's a better buy for everyone than an OTA.

Not to say I would say no to an AP-scope, quite the contrary......

Any inkling to when Mach1's will be planned for next year?
spring/summer/autumn...?

Regards from The Netherlands
Marco Meiling




From: michael mcdermott
Sent: Thursday, August 26, 2010 6:42 PM
To: ap-gto@...
Subject: Re: [ap-gto] 3600GTO- now accepting orders for delivery this Fall



I am hoping the production on your telescopes take a turn for the better, with much improved turn-around on mounts within the last few years!

--- On Wed, 8/25/10, Marj <marj@...> wrote:

From: Marj <marj@...>
Subject: [ap-gto] 3600GTO- now accepting orders for delivery this Fall
To: ap-gto@...
Cc: ap-ug@...
Date: Wednesday, August 25, 2010, 9:58 PM



On August 19, we began our notifcation process for "el Capitan" our
largest mount by notifying all people on the list. Today, we opened up
the order process to anyone who would like to order this mount. Most of
the parts have been machined and we have started assembly. We anticipate
that the first orders will ship in October.

If you have a large instrument or wish to mount multiple instruments
side-by-side, you may wish to consider the 3600GTO. Check out the
website for further details.
http://www.astro-physics.com/products/mounts/3600gto/3600gto.htm

Note that we now have a 27" Dovetail Sliding Bar that is perfect for
side-by-side arrangements.

Clear Skies!

Marj Christen
Vice President
Astro-Physics, Inc
11250 Forest Hills Road
Machesney Park, IL 61115
Phone: 815-282-1513
Fax: 815-282-9847
www.astro-physics.com
Please include this e-mail with your response.



[Non-text portions of this message have been removed]





[Non-text portions of this message have been removed]


Thanks: Sensitivity to non-orthogonal imaging gear on AP900

mjstn2008 <mjstn2008@...>
 

Rolando, (and all the others as well)
Being an experienced visual observer, who is moving in to a direction of doing some imaging to mix things up a bit, my concern is all about obtaining precise mechanical polar alignment in around 15 minutes. This and earlier posts have made me feel good about the 'quick align' procedure and thank you. Also thanks to Ray for pointing out his software which I also understand is very good.

I now believe the prior threads I had read on orthogonality of the camera to the mount are not of concern to me as long as the algorithms don't depend on exact alignment of my wide field camera and it sounds like they do not. The writers of those comments were perhaps confused or passing along invalid information. I am getting by today with 3-star losmandy polar scope align for 5 degree wide field shots and the issues I see there are in the slop and drift of the losmandy alt mechanical adjustment and ability to hold that setting which I now know are not an issue with the Ap900. The backlash in the alt adjustment is also rather annoying in initial setup. To give the mount credit, it may even be a defective Losmandy in my case. Losmandy G-11 is a fine mount and has served me well, it is just time to move up.

Thanks all,
Mark

--- In ap-gto@..., chris1011@... wrote:

In a message dated 8/25/2010 11:29:54 AM Central Daylight Time,
alanpatterson@... writes:


I had CG5s and a CGE, prior to the AP1200 and AP Mach1 that I currently
run. NexStar does a GREAT job of modeling the Mount and correcting within
the field of Stars used to align the Mount, in my case 2+4 Stars. I used both
drift alignment and PemPro on that CGE, and dialed in the PA as well as
the seeing would allow. My GoTos with the Celestron Mounts beat my AP
experience hands down.
I am not at all sure what this paragraph that you wrote actually means.

There are two ways to handle "Alignment".

One is to plop the mount down in any old orientation with regard to the
pole (i.e. close enough is good enough) and then by picking a few stars in the
sky, allow the software to model the resultant errros and adjust for it. We
will have this available soon, both in a basic version for the keypad and in
a more elaborate version in our laptop control program. Now, what this does
is to allow very accurate Go-Tos because it eliminates pointing errors.
This is great for the visual user who may have problems with other more basic
mechanic alignment methods. The main drawback of this method is that it
results in RA/Dec drift and field rotation, simply because the mount polar axis
is not aligned with the rotation of the earth.

The other "alignment" method is best for imaging, and that method actually
strives to align the polar axis with the rotational axis of the earth. It is
a true mechanical alignment versus a fake software alignment. My Quick
Drift method does this quite nicely with very good accuracy, but it may or may
not result in good pointing accuracy due to mirrror flop, optical axis
non-orthogonality, flexure or a miriad of other effects. However, when properly
mechanically aligned, versus fake software aligned, the mount will enable very
accurate imaging with CCD cameras with no field rotation. My precision
mechanical alignment of my observatory mount on Monday night now allows me to
image for hours UNGUIDED, with a 1 arc sec per pixel image scale optical
system. (the 305 Honders astrograph which I use has no mirror flop - all optics
are fixed in place and flexure is essentially non-existent, so unguided
imaging is possible).

The advantage here is that I can choose to guide or not guide, depending on
whether a suitable guide star is present. On Monday I imaged the Pelican in
narrow band H-a and could not find any suitable guide star for the framing
that I wanted, even in a 60 second guide exposure. If I was not properly
mechanically aligned, I would have had to give up on that one with the internal
guide chip camera that I used. Can a mount be fake aligned with only
software that compensates for improper mechanical polar axis alignment, that
results in both RA and Dec drift of less than 1 arc sec in a half hour exposure?
I don't think so.

Rolando


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