Object |
The Ring Nebula
(M57), in Lyra |
Telescope (Photo) |
Celestron 8" SCT on Losmandy G-11 Mount @
f/6.3 |
Telescope (Guiding) |
Meade ETX 90mm OTA @f/13.8 on Losmandy
G11 Mount |
Camera (Photo) |
Canon 50D DSLR |
Camera (Guiding) |
Meade DSI II w/PHD
Guiding |
Exposure Detail |
Uncropped, median combination of
17 images at 60 seconds each, ISO1600; RAW file conversion, full
calibration (flat, dark, bias, and flat-dark), and initial image processing
using ImagesPlus 3.75; final image processing using Photoshop
CS3 |
Location |
Caesar Creek State Park, Ohio (N39.513,
W84.020) |
Date |
06/05/098 |
Comments |
The top image in this sequence is the identical image and was
put through identical image processing as the image on the
bottom, with the exception of the flat field. See the
Glossary
for a definition of Flat Field. The bottom image shows
graphically how using flat fields with an image can improve the
overall appearance by eliminating optical-train defects like
dust specks and dark corners. |