I am after a script that will help me with my CCD drift alignment.
Currently I start taking a 35sec image, wait 5 sec's then press and hold the east arrow for 15sec's then press and hold the west arrow for the remaining 15secs. Inspect the image, which will show the stars making "V". I then adjust the mount, either the alt or az. depending on were I'm pointing. Then start another image wait 5sec then move the mount east for 15sec then back west again for 15secs. I do this till I get the stars forming a single line instead of a "V". I then double the duration of the exposure, and go thru the above procedure again untill I get a single line, double the exp. lenght and go again. I keep doing this using upto 10-15min exp and it gets very boring sitting there holding the buttons on the controller. Not to mention the sore fingers.
Does anyone know of a script that will let me enter a duration, wait 5secs then move the mount east for 1/2 the remaining time then move the mount back west for the rest of the duration.
Eg. put in a time duration of say 605sec. start script, script would wait 5 secs then move the mount east for 300sec at GUIDE rate then move the mount west at the GUIDE rate for the remaining 300sec.
It doesnt have to be anything fancy just a simple script that will save my fingers and probable the buttons on the controller.
The mount is a G11 with G2.
I have tried to do this my self but have no idea how to.
This is the script I use for the same task with EQASCOM. http://eq-mod.sourceforge.net/samples/CCDDriftAlign.vbs
All it does is it slews east for 30secs and then west for 30s.
So I have my image capture program running windowed, and then run this script and start the capture at the same time.
so if you are able to substitute the CreateObject("EQMOD.Telescope") with your gemini equivalent, this might work.
Maybe try "DriverHelper.Chooser"
I'm guessing you'd have to use the ASCOM driver for your G11.
Also look at the Maxim scripts. There might be something there that uses scope control.
for eg. I found this snippet from the recenter script at http://www.cyanogen.com/maxim_extras.php
see if you could use this with the eqascom script I mentioned.
' #2 -- Telescope driver
' Need to set this to the appropriate telescope model
' This will pop up a chooser box; you pick the telescope
' and set up the COM port etc. You can experiment with
' the Simulator
Set ch = CreateObject("DriverHelper.Chooser" )
ScopeProgID = ch.Choose("")
Set t = CreateObject(ScopeProgID)
t.Connected = True
Set ch = Nothing
Else you may be able to script the whole thing in Maxim which can include the capture as well.
Finally, I think this might work partially.
try out this script. It opens a dialog to choose the scope. then you can set it to track. but you need to find the ascom command to change the tracking=true to a slew at 1x sidereal.
Have you guys tried using PHD to align? Just connect PHD to your scope and camera and do a normal PHD calibration. Once calibrated, stop everything, go into the brain button and turn off guiding. Turn the scope east or west about 25-35degrees up, start capturing, pick a star and start guiding. Get the graph up and watch the dec chart, ignore RA. Adjust alt for a flatish line. Stop guiding, turn the scope up, get a star overhead and guide again. Adjust Az for a flat line. Rinse and repeat.
yep, we've been through quite a few methods including phd guiding and alignmaster.
we've found this method to be the most accurate, correct me if I'm wrong John.
its actually quite easy and removes the ambiguity you may have with the phd graph and whether its going up or down cause sometimes, it looks like its stable, and then it changes for a bit and then stabilizes.
with this ccd method, its very straightforward and either a straight line or a V.
as explained here http://www.observatory.digital-sf.co...nt_CCDv1-1.pdf
It should be possible to move the G11 east and then west with a script.
I have tried using PHD but found this to work better for me. I always had problems. I do think it was me more than then method. It may be due to me using dx/dy aslo. I will have another go. I do think it is better in some ways as you do get an instant readout on any adjustments made.
I suppose too, if I increase the rate at which I move the mount and decrease the duration I should get the same result in a shorter time.
John, the phd method bums out if your guiders F/L is over maybe 800mm. Changes you make zoom off the chart and you can't tell which way it went. In the dome I normally start with under 600mm then push F/L up to the highest I use to get it accurate. It can sometimes take 3 nights though to get it set, depends on seeing at the longer F/L. It's worth the time in the long run and I only do it if I've pulled the mount out.
If you use dx/dy charts that's straight from the camera with no adjustment for angle. We spoke to stark about it and you really need to use the normal charts and turn all guiding off and ignore RA.
The problem for me with the phd graph was that it could vary a fair bit due to seeing and you'll have to make an approximation of whether it is drifting or not.
I've seen the graph stay steady for a minute or so and then start drifting.
I've tried this a few times and it didn't work too well for me. and I wasn't using dx/dy. I was just watching dec drift.
with the ccd method, I use 2x2 bin as that makes the trails brighter and keep at 30 to 1min exposures. that takes 2 or 3 tries. when that seems ok, then I go for 2 min at 1x1bin, either 1 or 2 iterations, and then I do one 4 min just to make sure. but by then, the drift in Dec is not noticeable.
basically that's what you're seeing with this method, how far the star has drifted in dec, just that its easier to make out visually as you can see it as a point and the line. you're slewing east/west and coming back to the same point. so since you've made no adjustments to dec, the start and end points should be very close.
As I mentioned, the EQASCOM script works brilliantly for me. I just make multiple copies and edit the values for each. so I have one script on the desktop for each.
John, I'm pretty sure you can script this with maxim. I'll have a go when I get the chance.
Which driver do you use and does the ASCOM one work for you?
Al, new is good. I'm looking at the ole interfaces on my machine now to see how to control it all via maxim.
[edit]
you can't. Maxim only exposes a camera and the document (the image), not the scope. So you'd need to ascom to the scope and ole/com to maxim. I'll have a look at it.
John, I'm pretty sure you can script this with maxim. I'll have a go when I get the chance.
Which driver do you use and does the ASCOM one work for you?
Yes I connect via Ascom and use gemini.net
Quote:
Originally Posted by Tandum
Al, new is good. I'm looking at the ole interfaces on my machine now to see how to control it all via maxim.
[edit]
you can't. Maxim only exposes a camera and the document (the image), not the scope. So you'd need to ascom to the scope and ole/com to maxim. I'll have a look at it.
Interesting discussion, thanks for the info guys. I just got my EQMOD cable so looking forward to trying all this out, rather than having to press E/W on the handcontroller for minutes!
I manged to knock up a rough framework for a tool today. But I can't see how to make the scope move or at least it doesn't appear to make the simulator move. I'm trying to use this command in C# : scope.MoveAxis(DeviceInterface.Tele scopeAxes.axisSecondary, 100);
I have set tracking to sidereal and turned tracking on but the numbers in the RA/DEC boxes don't move. Anyone know of another command?
that app looks cool
does it work with the higher rate?
ideally sidereal x2 would be perfect as otherwise the trail would go out of the fov especially for 4 or 5 mins
timer in a script could be a simple loop as in here http://eq-mod.sourceforge.net/samples/CCDDriftAlign.vbs
but if you've got it working as an app then its great
are there commands to initiate the image capture as well, would be neat to see in your app as the seconds variable can be used for the slew time and exposure time
cheers
alistair
Unzip and run setup.exe. It will show up on the menus and in add/remove programs so you can uninstall it there.
The rate is the number of seconds to move 1 degree so you can change that but a rate change doesn't take effect if a run is already started. You need to stop it and start again. I set the range from 15 to 300 seconds. The other crap on the screen is mostly for debugging but I did add a honking big all stop button
wow that looks amazing, thats one serious looking stop button. I'll give it a whirl and let you know. John, look forward to your test results as well. sorry if I've hijacked your thread.
robin, I'm guessing that of you choose poth hub for the scope, you wont have to close maxim. I usually have stellarium and maxim connected to the scope via the hub.
It seems to open a new maxim so you'll have 2 on the screen. If the first has a connection to the camera the second will fail to connect to the camera. That's the way com seems to work. I haven't turned any camera coolers on either. I'm not sure if moveaxis is implemented in poth or if the .net assemblies for poth are inside the program. eqmod is a hub anyway. Also I altered the rate range to be from 15-300. 1 degree a second was a bit quick It's overcast here so I can't see if it works.
[edit]
I got it now. It's only starting a second maxim when I run it inside the debugger. Run the installed app itself and it latches onto the currently running maxim
and probable the buttons on the controller. 
