|
Options I would consider:
1) using live view and getting it as good as you can - I think this is the easy option.
2) using software on a computer which the camera is connected to, taking exposures and looking at the sharpnesss, adjusting focus until optimal.
Option 2 is aided by software which takes a rapid succession of frames showing them to you once they have downloaded and in some cases always zooming in to a star you select. Such software is Images Plus, Nebulosity2, DSLRFocus (if using XP or older OS), MaximDSLR, and there are probably lots more. Google those and you should find download/buy pages.
If I were you, I'd stick to using Live View at 10x magnification (presuming you can do that on the 450D) and save the hassle of a PC.
Roger.
|