It was taken at X2.5. Yes focus is accurate in real time, as long as the anglefinder C is adjusted correctly for either mag (1.25 or 2.5). My reason for doing this was to keep an eye on focus as the night gets colder and make an adjustment if needed while the camera is taking the 'dark' frame for in camera noise subtraction. This way you don't lose framing or guide star etc. I am thinking of trying a low light monochrome camera like this next if the ToUcam is not sensitive enough.
http://www.supercircuits.com/index.a...OD&ProdID=4166
I have tried stepper motors for focus and taking test shots etc and it is all right to do once. But as the night gets colder focus changes and all you do all night is chase focus.
What I do at the moment is sit inside and watch the exposures as they come in over wireless network from the laptop controlling the Canon camera to my PC inside. It is obvious when focus is deteriorating. It would be nice to go out without dark adapting and simply adjust focus while the camera is taking the dark frame without disturbing the running setup.
Unless you are dark adapted to attain good focus with dim stars is impossible. I have also noticed if I am tired or had one or two beers I can never get good focus without long dark adaption. With a bright laptop screen there is no problem even when very tired and more beer and or coffee.
I do have DSLR focus but have not used it much.
The small attached picture shows how much an 8mm lens on the ToUcam sees of the viewfinder. The second is a view of the full viewfinder.
Bert
L.
