6d, Flats not helping ?

[SAW]

Hi,

Recently got a 6D (un-modified) already have a 600D (modified). Last night I did some wide field imaging with it using a Canon L series 200mm f/2.8 lens, 60x60s lights, 20 darks, 20 flats and 20 flat darks. Tried stacking it with and with out flats in DSS and PixInsight but I am getting a really annoying glow around the edge and when I use ABE or DBE in PixInsight it makes it worse. I've tried flats and different histogram values but makes no difference. I don't get any problem with the modded 600D, is it just because it's full frame ? 

First image is just stretched in Pix and the second is with ABE or DBE done.

What am I doing wrong compared to when I use my 600D ? I do my flats with a light panel and adjust brightness to get the correct histogram this has always worked with the 600D.

There was no moon last night imaging and my neighbor does have security light that comes on occasionally but I was imaging the opposite direction.

Is it the lens ?

[Skipper Billy]

Did you cover the viewfinder? That camera is apparently quite susceptible to light leaks so lens mount and or viewfinder would be worth investigating.

[SAW]

No I never covered the viewfinder so maybe my headlight or neighbors security light could be to blame as this would of been facing their light ?

[Skipper Billy]

Even the light from the cameras screen can get in the viewfinder - a bit of silver foil will do the job.

[michael8554]

The small black rubber thingy on a Canon neck strap is for slipping over the viewfinder once you've slid the viewfinder surround off.

You can unthread it from the strap of course.

Michael

[Allinthehead]

Did you use bias frames?

[SAW]

53 minutes ago, Allinthehead said:

Did you use bias frames?

I used dark flats as bias in PixInsight.