Hi to all.
Today while making dark´s during the day, I got white frames due to light filtering.
My set up is with my ZWO ASI1600 MM pro camera, EFW & OAG & Guide camera, frame setting; cooling at -15°, scope covered, 300 sec exposure.
To make the story short;
1.- Initially I used a black bag to cover the camera/EFW/AOG/guide camera and the problem is gone.
2.- Then. I covered individually all other potential light filtering like the EFW / Guide camera or OAG and still getting white frames.
3.- Finally I covered only the camera as you can see in the two pictures, one from each side and is covering the camera,


End result, with the camera covered the white frames are gone.
Help will be appreciated, how can I assure there is no light coming from the back of the camera.
Any advise will be appreciated.
Regards.