ASI2600MC Pro OSC

ikkhatri

Hi Guys,

Reaching out as I have been struggling with this issue ever since I purchased the ASI2600MC Pro OSC camera.

When taking long exposures there is a bright circle that appears on my subs which is perfectly centered. This happened with my C8 Edge HD and now also happening with my Espirit 100ED.

Example sub -->: https://ibb.co/VCyycR3

The longer the exposure the brighter the circle is.

ZWO Team, could you please advise what could be the reason for this? Faulty camera/Issue with sensor? I have also reached out to others that are using the same camera with no isses.

Thank you.

terry56

ikkhatri My guess would be that you are getting icing up on the protective window - I have seen this on my ASI294MC-Pro. If it is, you should be able to see it on the window - cool the camera while it's attached to your scope and then take it off (while still running the TEC) and look for any signs of ice formation on the inside of the window - I could see a little white frosted circle. My experience was that if you did this with the camera not on the scope, the window picked up enough heat by whatever means to stop it happening. If you do it on the Esprit 100, you could probably just look into the objective lens and see the sensor and window through that - I know I can with my RedCat51.

If it is this, then you really need to recharge the desiccant (disappointing if this is a new camera), although others have suggested running the camera at 0°C for a while before cooling to sub-zero temperatures. I've done this with my 294 with some success. If it is ice, then running at 5°C would be an option in the short term at least - the dark current of the 2600 is supposed to be very low.

Terry

Tech@ZWO

Hi,
Please try in ASIStudio and share the related fit file with us via Google Drive, or Dropbox link.

ikkhatri

terry56

Hi,
Thanks for assisting with this. I can confirm there was no ice forming in the camera. I have also tried 0 and -5 degrees. I also purchased the L-Extreme filter as I was told it's due to light pollution. Even with the filter I don't see any improvements. On the other hand I do have an asi294mc pro and I don't have any problems with that camera @ -10

ikkhatri

@tech@zwo#50749

Thanks for your response.
https://1drv.ms/u/s!AgFClZHt1sdHanUnL2-mub5aJgM?e=zL8JjN

The above link has the fits file.

Tech@ZWO

ikkhatri
Can you tell us which one is your connection method in below?
https://astronomy-imaging-camera.com/tutorials/asi2600-guide-4-connection-methods-to-get-55mm-back-focus-length.html

ikkhatri

@tech@zwo#51166

Connection method 4, minus the OAG as I am using a guide scope.
Scope is a Espirit 100ED with 63mm back focus

I had a go again with camera temp set to -5.
The fits files can be found here:
https://1drv.ms/u/s!AgFClZHt1sdHbTnU1slWsSCoIbw?e=gzuSQa

Tech@ZWO

ikkhatri 63mm back focus

Why it is a 63mm back focus? Have you ever tried 55mm and what is the outcome?

w7ay

@tech@zwo#51270 Why it is a 63mm back focus?

Because that is what the optical train of the Espirit 100ED is designed for -- to provide a greater range of imaging accessories to be added between the OTA and the camera.

Chen

ikkhatri

w7ay

Thank you Chen. Appreciate you jumping in to respond.

tech@zwo It seems like I'm not getting anywhere on this forum which is quite surprising and now leads me to think I may have to reconsider another brand for all my future camera and accessory purchases. (Considering I have spent so much money with ZWO products such as asi294mc, 290mm , 174mm, 462mc, asiair pro, 2 OAG'S and currently waiting for the asiair plus).

I would like to thank all the other members that atleast attempted and advised of things to try which the ZWO tech's haven't up until now.

Please close this thread if the need be, I am no longer requiring assistance as the official zwo tech's are not helpful at all!

terry56

I've just had a look at the images you posted and they looked pretty good to me except the stars in the corners are very elongated which suggests that you need to increase the spacing - see this . The stars are very comet-like.
As for the brightness issue, I did a background extraction on one of your Tarantula images and the background looks exactly as you would expect from a bit of vignetting with about a 10% drop off in brightness into the corners, but falling off uniformly as you would expect. The same applied to the images of NGC6357 that you posted earlier. Is it possible that the bright circle you see is some artefact of the way the image is being displayed? I know I can get this when I look at images when I use VNC to connect into my mini-PC on my scope.

terry56

Oops, that link should have been this - https://www.altairastro.help/info-instructions/instructions-howto/howto-adjust-sensor-reducer-flattener-spacing-for-better-star-shapes/