Capuring Flats

[DirtyRod]

Robin,

I've been using various versions of 4.1 as they have been released and the capture flats utility has these small spikes at 25 and 75% that give me saturation warnings. In some of the previous versions they were bigger and, at one point, they were every 5%. I do not see these when shooting darks or lights. Only when shooting flats so it's not a light leak. Just to verify, I took a flashlight last night out in the dark and shined it all over my imaging train watching the histogram to verify that do not have a light leak.

The first image is what I normally see on the latest 4.1 build and the second is what I see when I run a focus routine.

The flats work when I take them but wonder what I can do to get rid of the saturation warnings. I can adjust the exposure up or down and it will always tell me I have pixels too low, too high, or both. I never saw this behavior in 4.0 with the same gear.

Screenshot 2023-09-15 063142.jpg (134.87 KiB) Viewed 5977 times

IMG_2350.jpg (93.21 KiB) Viewed 5977 times

[admin]

Hi,

for the warning in the flat capture, I think I can see a small spike in the histogram graph almost on the left hand side - just above the 0% level. I'm fairly sure that is what is triggering the warning. I suspect that if you zoom in on different parts of the image you might find some black or near black pixels somewhere. If you enable the ROI box for the histogram then you can move that around the image to try to find the black areas and the areas that are giving the 25%/75% spikes to see what they look like visually.

I actually have an 071MC here, so I have just tested with the latest 4.1 and found nothing odd, so it seems likely that it is either a settings issue or perhaps a hardware issue.

I would suggest trying 4.0 again to make sure that the issues vanish when you switch back to the old version and appear when you are in 4.1. You can have both installed side by side. If that's the case it would rule out any hardware issues.

You can press the <CTRL> key while opening the camera to go back to default settings just in case some setting has got changed in an unexpected way.

One difference between 4.0 and 4.1 is that 4.0 has a slightly older version of the ZWO SDK in it (1.29 rather than 1.30) - that could cause an issue, although ZWO are usually very good at not causing bugs with updates.

cheers,

Robin

[DirtyRod]

Thanks. I will give those suggestions a try.