I often use a deep sky filter for emission nebulas if I do not like the unfiltered image. I do not use a filter for galaxies. The camera needs about 2 minutes initially to build up to a very sensitive state. Then I move from object to object.
The exposures are 3-15 seconds and this allows time to observe a dozen or more objects in a session. An 18 inch mirror gathers enough light for most objects of small angular size and the very small fov helps to overcome urban light pollution.
Your setup shows what can be done with EAA. All amazing images. Those shots of the galaxies are awesome and show what a large scope can do with a good camera.
How long of an exposure does it take before you can see the galaxies and do you need a filter?
Thanks for sharing your experience. I am sure other members can benefit from what you are doing with a large dob and EAA camera.
I enjoy viewing galaxies and have used the following set up for several years;MC extreme x2, 18 inch Dob with tracking and a color analog Speco monitor. I control the camera with my notebook and adjust images on the monitor. Instead of recording a digital image on the laptop I snap a photo of the monitor w my iPhone. Twisting knobs on the monitor gives a better view for me that dealing with digital signals on the laptop.
I am able to view multiple objects and display them to the public and myself. The images are not attractive astrophotographs but are in color and easily visualized. The Dob has about a 1/4 degree FOV.
Copyright 2016 Louisville Astronomical Society, Inc.
Louisville Astronomical Society, Inc. is a 501(c)3 non-profit organization. Kentucky, P.O. Box 17554, Louisville, KY 40217