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Strange things in my lights

Acquisition Deep Sky Help Needed Artifacts
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Adrimt33 avatar
Adrimt33 avatar
Hi everyone 
I am new to the astrophotography world.
The other day while i was capturing my light frames i noticed some strange spots. I don´t know if it is dust or if something is wrong with my set up.
I would appreciate any advise about what it is and if i can remove it 

Thank u all in advance
Richard Mak avatar
Richard Mak avatar
That's dust on your sensor or sensor window.
andrea tasselli avatar
andrea tasselli avatar
As mentioned above it's dust motes. You need to take flats in order to remove them (and correct for many other things besides). Depending on what you are going to use for processing the raw images there will be the right procedure to follow for light frame calibration. Just google it up or ask here for more details.
Beat Wirthmueller avatar
Beat Wirthmueller avatar
Hi welcome to this hobby - hope you will have a great time!

Yes it is certainly dust - it is always a good idea to keep the camera sensor or the screen on it as clean as possibly - same as with daytime photography. Next step is taking flats, bias frames and dark frames and so on. When I started with astrophotography  I skipped all these additional procedures until I noticed how important they are for the final image.
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Adrimt33 avatar
Adrimt33 avatar
Thank u all for your advice

I will try to clean my sensor with the proper tools and the calibration frames.
Dunk avatar
Dunk avatar
One more tip: after cleaning, if you can keep your imaging train assembled it should prevent this happening again. Not always possible I know, but thought I'd mention.

CS.
Rick Krejci avatar
Rick Krejci avatar
Thank u all for your advice

I will try to clean my sensor with the proper tools and the calibration frames.

If your camera's still attached to your telescope and you haven't moved it, you can still take flats if you want to try to salvage.   Easiest is to point to the sky at dusk/dawn (away from lights and/or the moon) and take some short exposures so that the image histogram if about 50% (the image looks medium gray unstretched).    If you want to do this, do it before cleaning the sensor so it records the dust.    I also take a bunch of bias frames (shortest exposure frames with the telescope covered at a similar temp as you took the shot with).    With just bias and flats, you should get rid of most of the issues.    I generally don't take darks or dark flats since the thermal signal on the ASI2600 is insignificant even for 300 sec exposures.
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