Full Frame Focus Exposure Time By Filter

[Joe R]

Hello All.

It’s been some time since I imaged last, but I did so last night and continued using AA8. All went well, but I did run into two issues and need some help.

First, when imaging/running a sequence including guiding in AA8, AA8 froze up for about 5 seconds, which happened every minute or so throughout the session. Everything AA8 froze and I couldn’t click on anything else AA8 but it always recovered. My laptop wasn’t freezing as I could navigate elsewhere. I do have the Cameras control in background checked for both ASCOM and non ASCOM cameras as shown below. I do have AA8 connected to the RS232 port of the mount for guiding.

My setup is a QSI683WSG with internal filter wheel, QHY5Lii guider, Robo-Focuser, powered USB hub, Losmandy G11, i7 laptop running WIN 10.


The second issue is when focusing any of my narrow band filters there’s a false focus that skews the final position. This seems to happen at longer durations of 10-15 seconds, but 5 second exposures seem to cure the issue. I added a pic of the issue and you can see that the 6th image is the actual focus so the 3rd image was nowhere near focus. This resulted in images out of focus.

Any help is greatly appreciated.

Thanks!

Joe

[fabdev]

Hello,

1) It's hard to tell, but I think that it could be caused by autoguiding. Next time take a look at the guide window and see if the interruptions happen when a pulse is sent to telescope.

2) 15 seconds of exposure seems too much, considering that strongly defocused stars are clearly visible. Step 70 with 9 position seems too much, since all star seem too big in the last exposure (if they are really bigger than 12-15 pixels), maybe Step 50 is better.
However, if stars at focus position have a size of 7-8 pixels, then it's better to use the LaD algorithm instead of SmD. Another test could be adding the option "Software 2x2" and using the algorithm "SmD".

Clear skies,
Fabio.

[Joe R]

Hello Fabio.

Thanks for the quick reply.

I believe the freezing is being caused by guiding because when I was setting up and taking images from both cameras, but not guiding (framing and focusing) there was no freezing up of AA8. It seems it’s only when actually auto guiding the freezing occurs.

As for FF focusing, I’ll experiment as you suggested.

Thanks Again.

Joe

[Joe R]

Also, Fabio,

I use the 70 steps because there is a large difference in focus positions between LRGB and Narrow Band filters, about 150-200 steps, this is my attempt cover the all filters. Is there a way to account for the different positions between filters so I can reduce the step size?

Joe

[fabdev]

Hi Joe,
no, but I think that you can solve also keeping step 70, but switching to LaD or Binning2x2
Fabio.

[Joe R]

Fabio,

Thank you. I’ll make the focusing changes as you recommended. Hoping to image the weekend and will let you know how it goes.

Any insight in the freezing? Also, is there a way to configure AA8 to use the output on my guide camera to guide? My current setup uses the RS232 port while my guider would plug into the auto guider port. In PHD2 there’s a setting that allows guide pulses to come directly from the guide camera, but haven’t seen anything similar in AA8.

Thanks again for your help.

Joe

[Joe R]

Fabio,

While doing some research I came across a thread (on another site) indicating there are a couple software switches in the Gemini driver that has been known to cause freezes when using the RS232 port for guiding. I plan to try these settings and will report back with the details. Crossing my fingers!

Joe

[fabdev]

Hi Joe, I would not use the RS232 as well. With the QHY5IIL I would use the integrated autoguider port. In Astroart the setting for the Guide Protocol, in the Telescope Window, is "Camera 2 relay" or "ASCOM Guider relay" (the 3° item in the list).
Fabio.

[Joe R]

Hi Fabio.

I think that’s what I will do. I’ll still connect to the RS232 port for gotos and plate solving. Hoping to image the weekend and will let you know how it goes.

Thanks Again.

Joe

[Joe R]

Hello All.

I imaged last night but couldn’t get the autoguider to calibrate using full frame guiding. I had the QHY5Lii plugged into the autoguider port of the Gemini 1, and tried all available Guide dropdown menu options available under Telescope Control panel. I got the mount didn’t move error no matter what selection used.

Not sure if this matters but for the goto selection I used ASCOM Diver which pulled up the Gemini software that successfully connected. I did have AA8 controlling the mount via the RS232 port which worked well. I tried with and with out the GOTO connection just so rule out that being a problem. One thing I didn’t change is the com port setting on the Telescope Control panel, perhaps this is part of the issue(???).

Lastly, I pulled up PHD2, which worked just fine and used that for auto guiding the rest of the night.

Not sure what the next steps should be but any guidance is greatly appreciated.

Joe

[bill]

Hi Joe,
Regarding using the autoguider port on your Gemini-1, you may have non-functioning guider IC circuit.
Depending on the version of your Gemini-1, Round DIN or RJ style jacks, this FAQ may help you.

https://gemini-2.com/faqG1.html#Q17

I have both G1 & G2 on 2 separate mounts and have used a Lodestar & SX-autoguiders via. relays on both in the past.
Now I mainly use the G2 which supports Ascom/Ethernet for guiding which works very well.

Best Regards,
Bill

[Joe R]

Hi Bill.

Thanks for the reply. As I noted I am able to use PHD2 to guide just fine. I’m wondering if it’s a setting in AA8 that I’m overlooking or the Gemini driver. I can get around this problem by use g PHD2 to guide but I really want to only use AA8 100%.

Thanks again.

Joe