Star Testing

Just bought the Suiter book on Star Testing. Been meaning to buy it but have not been quick enough on the draw to get a copy. I am very interested in get to review this book in it's entirety. I have not gotten to look at it thoroughly before.
Floyd

Hi Floyd,

I have the book also, but have not had the tenacity to plow through it yet. If you can figure it out and "distill" it down for the rest of us, I would appreciate it

David Simons

At least a half of it is empty talk. The man illustrates diffraction of light through quantum diffraction of particles - used to be the other way round...

The other half is very useful (if you can stand with the first one - I couldn't).

Dmitri

Floyd,

Suiter's treatment of diffraction theory is quite complete making the book read more like a college text than a how-to guide. But, if you read the material on each kind of optical defect and study the pictures of the diffraction patterns you can get a very good feel for the kinds of patterns to look for when at the eyepiece. Most, if not all, of the derivations and wave theory explanations could be skipped without losing any value when comparing star patterns. The gory mathematical details are fascinating to some, while others, unable to grasp them, find them unnecessary(empty).

I spent the better part of 2 nights looking at my setup and comparing to his diagrams. Some very important things to keep in mind:

- To compare the star test patterns, you need to defocus approximately the same amount as Suiter's diagrams. He explains how to calculate the focus movement for a particular F#.

- The patterns in the book usually illustrate the diffraction pattern inside, outside and in focus. Note the in-focus pattern is greatly magnified w.r.t. the out of focus images- I really had to look hard to see characteristics of the diffraction rings in focus.

- I never had seeing conditions good enough to do a decent star test. I made an artificial star using a white LED flashlight and a pinhole - worked great.