AstroGab

Astrophotographers hangout. Invite friends and notice chat bar on bottom.

Hi Guys,

I was just curious if anyone here uses MaximDL as a guiding software. I'm fairly new to Maxim but I have been using it to guide and it does seem to do an OK job. When I watch the graphing component I get nothing but shark's teeth and I can't seem to smooth out the 'Curve'. Is this graphical saw tooth display typical or are you getting a smooth curve?

Thanks.

Gregg

Views: 247

Reply to This

Replies to This Discussion

I use Maxim to guide. I've not seen shark's teeth. I'll take a look next time I shoot. Which graph are you seeing this in?
Hi Charles,

I may be over reacting to the situation but I when see that sort of motion on a graph I think the guiding is over correcting then under correcting and starts that 'Rocking' motion.I have thrown up a screen shot I took a couple weeks ago of Maxim in use however it's not such a good representation of the graph as it's on over the course of a minute I believe.

Anyway, if you don't mind and you remember, I would appreciate you taking a look or taking a screen shot of your guiding graph while guiding.

Thanks Charles.

Gregg
Greg,

I use MaximDL for guiding and the curve is pretty smooth most nights. If you are getting a saw tooth curve it could be backlash in your mount, although that often causes a square wave. You may want to look at your minimum and maximum move settings. If the minimum setting is too high it may drift quite a bit befor it corrects, hence the saw tooth. You can go to the site below to determine what your minimum and maximum setting should be.

http://www.ccdware.com/resources/autoguidercalcv4.cfm

Thanks,

Bernard
Hi Bernard,

This looks like the information I was looking for! In the CCDWare Calc. they refer to the "AutoGuiding Method" and give three choices, being "Guider Relays, Direct Guide, and Auto Dither". Do you have any idea which one of the three would suite me better? I am using a DSI ll camera with a GPUSB from Shoestring Astronomy.

If I am following the calculations correctly my guiding rate is 0.5 sidereal. My autoguider image scale is 206.265/500mm x 9.6μm = 3.96 whereby 206.265 = constant; 500mm = FL of guiding scope; 9.6μm = pixel size (DSI PRO as guider)

The peak to peak allowable error calculation is referring to the actual imaging scale I take it?
Imaging scope FL = 770mm; pixel size = 8.6μm so 206.265/770mm x 8.6 = 2.30 75% of this is 1.73 Does this sound correct to you?

Thanks again Bernard I hope this will eventually do it. Cloudy now but I hope to get out tomorrow and give it a try!

Gregg
Gregg,

I am not that familar with the GPUSB but it lloks to me like you need "Guider Relays". This setting is used when you have an external guide camera correctling the mount. I can see that the GPUSB connects your mount to a computer, but what do you use as a guide camera?

Your calculations look correct. Based on what you have I come up with a Min. Move = 0.115, and a Max. Move= 0.691 assuming Max Move = 3 X Min. Move. Is this what you got?

Bernard
Hi Bernard,

That's pretty darn close to what I ended up with. The reason I wasn't so sure on the Autoguiding Method was that in Maxim under the guiding tab "Autoguider Output Control Via" there are several to choose from. I see the "Guider Relays" but the one I have to use is the last one down the list which is "GPUSB" The camera guider is a DSI PRO. I noticed that there were several other good apps and guiding info inside CCDWare!

Thanks Bernard!!

Gregg
Gregg, what mount are you using? I also use from time to time the dsi as guider and dont use the Shoestring device...
Hi Emil,

I didn't realize that you could use the DSI as a guider without using the Shoestring GPUSB devise. Would you be able to 'Talk' me through setting it up? I am using a Celestron CGE mount.

I got some GREAT advise from Bernard about setting up the MAX MIN move under the advanced setting tab. I think it has made a smoother looking graph with respect to errors. I have tried it with the new settings but not under the best of conditions. I am still waiting for a better night for testing but there looks to be improvement!

Any comments or suggestions are always appreciated and valued! I am slowly getting there!

Gregg
me too. I've got a cGEM mount and would love to use my DSI II over the Starshoot anyday of the week,
Normally I use the ATIK 16IC for guiding but so long my main imager was serviced I had so swap the imagers. That means that the Atik was use as main camera and the DSI 1 color as guider.
You have to use as connection under Maxim the option "telescope" in this way I managed to guide with the DSI. Also depending on the focal length of the guider scope you have to play with the calibration time.
If you wish I can send you some screen shoots.
Regarding the max min movement you have to pay attention to the peak to peak error in your guider in respect to the resolution of the main imager.
Emil
Hi Emil,

Thank you for the information. I wonder if not using the GPUSB from Shoestring the commands are sent quicker or slower to the motors? Anyway, if you could send me some screen shots that would be great. How did you arrive at your min/max setting under the advanced settings in Maxim? From my guiding and imaging parameters above, do you think Bernard and I calculated the min/max correctly? If you could also send/post a screen shot of the Maxim graph while you are guiding?
Thanks Emil.

There sure is a lot of great help in the group!

Gregg
I don't believe that the commands are quicker or similar, also I haven't seen a difference between ST-4 and standard (over RS-232 port) guiding.
Here you have a screen shot, unfortunately is a ATIK version. Mount is EQ-6 Pro with EQMOD

The min/max setting are in my case calculated by CCD Autopilot.
Optics: main imager is now QHY 9 bevore was a Kodak 1602E based camera with a 9 µm pixel size focal lenght 500 mm
Guiding: Celestron 102/660 mm with DSI 1C or ATIK 16IC

RSS

© 2019   Created by Charles Dunlop.   Powered by

Badges  |  Report an Issue  |  Terms of Service