My first spotting scope! I got my Celestron Ultima 80 on an internet special for $189 about four years ago. (Unfortunately it was stolen out of my car along with my binoculars and field guide when I left my garage door open over night and didn't lock my vehicle.) In good light this scope will surely help you pick out those peeps on the mudflats. My father-in-law, Lynn Davenport, also has this same scope and we've added several life birds using it!
As is common to most spotting scopes, color transmission and image steadiness are reduced as you increase magnification power. The image also starts to blur out toward the edges of your viewing window. Eye fatigue does become a problem after extended use. This scope is not great for low-light situations. A good tripod will help. We use the open car window as our viewing platform more often than a tripod. It just depends on where you are birding.
While visiting the Idaho Bird Observatory recently I was able to look at soaring hawks through a highend Swarovski spotting scope on a great tripod. It made all my past scope use look pathetic, but the price tag governs a lot of my equipment purchase decisions.
The Celestron Ultima 80 is a good value for young and beginning birders. I am still in the cheap stage of life and I recently purchased a $99 special Eagle Optics Denali. We'll see how it does and I'll post a review for it eventually.
A great new website, Spotting Scope Review, has just been launched. This website/blog focuses on spotting scopes and related accessories. There will be dozens of reviews by the staff of Spotting Scope Review and you can submit your own review as well. If you are in the market for a spotting scope, check this site out first to get your education on them.