Flat problems with ASI 1600

matariki

Hello,

the problem is not new but I still did not find a solution to this. I tried to search google but in every forums or user group I just find people with the same problem but no solution.

I am speaking of the problem that blue / OIII flats have a very strong pattern in them and are unusable, see the example image below:

The top row is (R, G, B) flats, the bottom row is (Ha, OIII) flats. The Ha and OIII flats have been taken with long exposure time (30s) but it doesn't matter, I tried very short (0,5s), medium (2s) or long exposure, all the same result.

This problem only occurs in blue spectrum so it has to be some kind of reflection. Is there a official statement from ZWO about this issue and how it can be solved?

Best regards,

Denis

Sam@ZWO

sorry, we heard such feedback from customer

we also ask this to panasonic but get nothing from there

I think you can calibrate your data well with this flat right?

matariki

Hello Sam,

I was able to fix the blue filter by flipping it around but OIII still has the same problem even after turning it. Did you change anything between v1 and v3 of the camera on the cover glas? I have talked to some people that use the v1 and they seem to not have this problem.

Best regards,

Denis

Sam@ZWO

Matariki wrote:
Hello Sam,

I was able to fix the blue filter by flipping it around but OIII still has the same problem even after turning it. Did you change anything between v1 and v3 of the camera on the cover glas? I have talked to some people that use the v1 and they seem to not have this problem.

Best regards,

Denis

no, sensor is the same

andreas1969

Sam wrote:
sorry, we heard such feedback from customer

we also ask this to panasonic but get nothing from there

I think you can calibrate your data well with this flat right?

Hi Sam,

I have the same issue, the pattern shows on both flats and light. Any idea of the reason? Any fix? I also get halos from bright stars. Are these problems connected?

P.S. This pattern is also visible with no filter.

Sam@ZWO

sorry, we think the halo issue is because the sensor's protect window is not coated

for the OIII flat issue, we don't know the reason