BirdForum is the net's largest birding community dedicated to wild birds and birding, and is absolutely FREE!

Register for an account to take part in lively discussions in the forum, post your pictures in the gallery and more.

Reply to thread

Message: <blockquote data-quote="kabsetz" data-source="post: 3172370" data-attributes="member: 10167">Ron,Thanks for the material.I'm sure I understated the importance of focus if we are thinking of obtaining actual MTF curves with a test setup. There, obtaining a precise focus would be paramount. My starting point here was rather what happens when we use the binoculars, and I'm using MTF curves here rather as a diagrammatic way to better understand and "visualize" what happens with the image. As far as I know, you are the only one of us here on BF who has been able to put together a test setup and has learned the necessary skills to actually do MTF testing at home. The rest of us can only study model curves and do simple resolution testing. I have enormous respect for what you have been able to achieve.In visual use, our eye accommodation to a larger or lesser extent compensates for the defocus aberration, but my point is that the more there are of other aberrations, the less effective this becomes and the more problematic the image.Kimmo</blockquote>