I've reached home and have been able to Photoshop a few images from my Missouri eagle trip. My verdict on the digiscoping setup is: It works, sometimes. Manual focusing can be a drag, and I fear that the wind made the tripod too unsteady much of the time. But enough of images were sharp that I was able to conclude it is a viable setup when extreme magnification is required. I calculated that under ideal conditions it is five times more powerful than my 300mm lens with 1.4x extender, or the equivalent of 2,200mm, 44x. Here are two images of the same scene, the top one digiscoped and the other from the DSLR.

Digiscoped

DSLR

The DSLR version is heavily cropped to appear the same size as the other image. I think the eagle on the right is better in the digiscoped version, but the one of the left is slightly out of focus. The depth of field is very shallow with the scope even at that distance, which means focusing is critical and can be difficult.

This was my fifth eagle hunting trip in three years, two to Squaw Creek and three to the Mississippi River near Burlington, Iowa. I suppose that begs the question whether it's worth it to pursue the same images over and over. But I got some images on this trip that I didn't get last year, and the Squaw Creek experience is different from the Mississippi River experience. So I'm pondering the usual January Mississippi River trip.

A trip report can be seen on eaglephoto.net, and photos have been uploaded to thomasoneil.com.