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First test of f6.3 Reducer on M20, M8, M17, M16, NGC 2070, NGC 253, NGC 5139
Last Tuesday Night I tried the Meade f6.3 reducer for the first time with reasonably good results considering smoke was hanging around from local backyard fires; just 25 quick shots of each object a quick stack, process and crop.
I do seem to be getting considerable vignetting of the images; it is my understanding that by adding the flat frames this can be reduced in the stacking process as the flat frames show any vignetting (and they do) and this can be accounted for in stacking, however vignetting was still very apparent in all shots.
Would where I place the reducer in the optical path make a difference or is the camera censor size an issue or something else?
The reducer is attached onto the rear cell of the SCT, then the zero shift micro focuser. T adapter & ring then Camera. The Sony Nex-3 camera has a 14.2 MP CMOS Image Sensor with a size of 23.4 x15.6 mm
A little help or insight into this problem of vignetting would be appreciated, thanks.
All shots attached are:
25 X 25 sec Subs at ISO 1600
10 Darks
10 Flats
12 inch Meade LX200 (Alt/Az Mounted)
Sony Nex-3 Camera
Stacked in DSS
1. Triffid Nebula M20
2. Lagoon Nebula M8
3. Swan Nebula M17
4. Eagle Nebula M16
5. Tarantula Nebula NGC 2070
6. Sculptor Galaxy NGC 253
7. Omega Centauri NGC 5139
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