Celestron 11055 Instruction Manual page 56

The exposure times listed here should be used as a starting point. Always
make exposures that are longer and shorter than the recommended time.
Also, try bracketing your exposures, taking a few photos at each shutter
speed. This will ensure that you will get a good photo.
Keep accurate records of your exposures. This information is useful if you
want to repeat your results or if you want to submit some of your photos to
various astronomy magazines for possible publication!
This same technique is used for photographing the Sun with the proper solar
filter.
52 • Celestial Photography