What might cause this issue (ASI 6200 mm pro) - Forums

Hi all,

I am experiencing something unusual with my lights and I would appreciate any share of wisdom.

What might cause the below pattern on the frame ? Light getting into the filter wheel ?

I thought maybe some strain on the camera window but flats don't show anything like this. I am a bit puzzled....

Below light taken with my ASI 6200 mm pro (Red filter)

Thanks and all the best,
A.

PS: don't see anything like this with my NB filters.

Aygen,
It certainly looks like 'light leak' to me, or possibly that the red filter is not orthogonal in the filter housing. Check to make sure of these items first before moving on.

The only thing else I can think of is possibly some type of smear on one of the optical surfaces - camera, filter, etc..

Just some thoughts. Best of luck.

- - Steve

Thank you Steve for your answer.

My first thought was also light leak but I am not so sure… a smear on the camera window might explain it. Since I have been doing mostly NB (and started only lastly to get also LRGB with my NB), this might explain why I never noticed it… ! ?

I will have to look at it.

Best regards,
Aygen

Hi Aygen,

I think this is caused by a bright star near the field. Please check.

best, Christoph

Good morning Christoph,

Thanks for chiming in.

I am currently shooting at the Elephant Trunk, and as per my frame, there isn't a very bright star near it - but I need to double check. Thanks for your suggestion.

Best,
Aygen

Also can be a street lamp nearby Aygen😉

My scope is located in the "middle of nowhere" South in Spain

)))

but thank you.

This is definitely the light leak. Are you using ZWO 2" 7x filter wheel? I was facing the same issue and after couple of hours playing with the torch around the scope I realized that the USB connector is causing this issue. try to use tape to cover the gaps.

Yes, I do have the 2" 7x filter wheel !

That's so crazy - I will definitely follow your recommendations. I can't believe that in 2022 we still keep having this kind of issues.

I will definitely use tape and others stuffs to cover the gaps and then will give it a new try. Arrrf…..

I need gently but surely move away from this brand…. I know they are quite a lot of "happy people" with ZWO (as I was), but come one, this shouldn't happen.

Thank you again and I hope my issue is solved thanks to you

You may face the same issue with other brands as well, this is fine

later on you can just put some black sponge around the usb connector from inside.
I think astrophotography is about struggling with equipment all the time. IMHO if it was so easy to get great results without any afford there won't be any interest in it. Manufacturers just trying to produce usable equipment and deliver it to production as fast as possible. So without proper QA we are getting this..
Oh and one more suggestion - if your tilter plate has a big gap - cover it as well.

Clear skies!

Thank you Vilen.

Agree on most of your statement. But they need to ensure proper quality control - this doesn't cost that much but can have such negative impacts on end users.

Clear skies to you as well and take care.

Best,
Aygen

Hi Aygen,

I like to double Christoph‘s words: I had the same with both of my cameras (Asi 294 and Asi 6200) on both of my Taks (Epsilon and CCA). Each time it was clearly a bright star outside the FoV causing the issue.

CS
Frank

Hi Frank,

I have to consider definitely all the options, including Christoph's and yours. I am just a bit puzzled because the nearest bright star around would be Garnet Star (Mu Cephei) and the way I have framed my target should prevent this…

Thank you and clear skies.

Best regards,
Aygen

I also would argue for a nearby bright star- 2nd or even 3rd magnitude could be more than enough to make trouble. What are the coordinates/size of your field?

You can try to reproduce the issue. I‘m pretty sure you already can see the pattern on a single subframe. Go for that again and then move the FoV a bit closer or wider from the star. You should see the difference immediately.

CS
Frank

I believe that

Frank Breslawski:
Hi Aygen,

I like to double Christoph‘s words: I had the same with both of my cameras (Asi 294 and Asi 6200) on both of my Taks (Epsilon and CCA). Each time it was clearly a bright star outside the FoV causing the issue.

CS
Frank

This is a wider field view cropped from my recent wide field image of the elephant trunk nebula. If my platesolving skills don't let me down the three stars in one line in the upper part fit to Aygen's image (rotated 180 degrees compared to my shot). So the bright star at the bottom could be the source of the stray light. Direction of the light rays doesn't fit 100% though ...

Clear skies
Wolfgang

Here is my FOV :

The pattern is located just below the coordinates (J2000 etc.) up left....

On the second image, there is indeed a bright star as I mentioned.

Garnet star or mu Cep, at m=4?

The multiple stray light lines are usually a dead giveaway that it is a bright star outside of your FOV. I have seen this with my ASI cameras (294, 2600, and 6200). I also have experienced light leaks and had a lengthy discussion in a forum here on Astrobin about it. In my case, the leak was coming from between the tilt plate and the camera casing. And this has been reported by others over the past few years. A light leak, at leak in my case, looks more like a blob of light, not rays of light like from a bright star. I solved it by closing the gap with black electrical tape.

That is the artifact from a bright star. In the FOV of your scope but not within the FOV of your sensor. If you slew a few degrees in any direction, it will likely disappear. That would be definitive whether its a star or a light leak. I was imaging NGC1333 a while back and had an Edge as well as a short refractor on the same target. I had the same exact pattern in both scopes…

Thank you all for your kind help - that's why I really like this community !!!!!

I will thoroughly a) cover all the possible gap with electrical tape b) perform some test in the field to confirm about the bright star being around.

Christoph Lichtblau:
Hi Aygen,

I think this is caused by a bright star near the field. Please check.

best, Christoph

I've also seen this when there was a bright star just outside my FOV.

Aygen:
Hi all,

I am experiencing something unusual with my lights and I would appreciate any share of wisdom.

What might cause the below pattern on the frame ? Light getting into the filter wheel ?

I thought maybe some strain on the camera window but flats don't show anything like this. I am a bit puzzled....

Below light taken with my ASI 6200 mm pro (Red filter)

Thanks and all the best,
A.

PS: don't see anything like this with my NB filters.

There is something on the sensor protect window. Perhaps cleaning solvent smear, fog, or it could be light frosting on the inside chamber. I would check the camera itself out here.

Same applies to the filter, check that as well.

Aygen:
Agree on most of your statement. But they need to ensure proper quality control - this doesn't cost that much but can have such negative impacts on end users.

I have also seen this in one of my images, it was from a bright star quite far from the object. As far as quality control, you won't get that from mass produced products from China, or anything from there. I have a friend that uses ZWO camera, filterwheel, OAG, and he has black tape on everything from light leaks.