Quote:
Originally Posted by Rigel003
I think you'll find that if you want the best focus in your images you'll ultimately need to go for a software solution using your laptop e.g. DSLR Focus or Images Plus. They'll give you a much higher degree of accuracy. I'd put the money towards one of these.
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I fully agree with Rigel003.
Had the chance to try all major methods like Finder, Magnifier, Hartmann mask, Knife ede,
PC-Dslrfocus, PC-Imageplus, Zoom into the result screen on the camera,
but if i wanted to be sure to get the "optimum" in Focus,
Notebook plus Software gave me the most accurate focus.
Another good but old solution is the knife-edge method, this was the
best way in the time of analog imaging. As you can
have in digital age the result immediately (without mount and unmount of the DSLR) the knife edge is for me
to cumbersome and oldfashioned.
3rd best solution is to test the sharpness of the stars in the biggest
magnifacation on the DSLR result Screen and comparing smallest starsize with one
older image i have stored on my card which has a perfect focussed
image on it using the same lens or telescope.
To get perfect Focus with DSLR and Finder plus magnifier is in my eperience only luck and very seldom.
The image in the finder look very soon sharp.
But in reality in my case they were are NOT PERFECT SHARP!
It really does not matter if you use a Pentax-, Canon- or Olympus right angle magnifier,
this method cannot compete with the PC-SW method. Also with methods like Hartmann mask
i could not get the accuracy which is needed.
In Internet at pages of different astrophotographer who
do quality images which i admire, i could not find any who do not use the PC for focussing no matter if they
still work with DSLR or with CCD.