Baltar 100mm f/2.3

Great lens for the value and a good time to upgrade. This lens is the second edition of the same lens from Canon with a few changes. The original 100-400mm lens was released September 1998 and was a push-pull style lens. I used it for 20 years without a problem. Version II is a twist style with the barrel extending based on the twist. With an upgrade to the Canon 5D MkIV body, I new I could get better performance from Version II of the lens. Version II was released November 2014 (16 years after the first release). The focus lock is quick in all lighting conditions and there are three image stabiization modes. Mode 3 image stabilization is interesting. It is active and ready for use the moment the shutter releases, but actual stabilization is not in effect until that precise time. The view seen through the viewfinder is not stabilized, but I had a hard time detecting this. You are able to follow your erratically-moving subjects (e.g., birds in flight) without fighting against image stabilization. Notes: I think any used version of this lens in good shape should be functional for another 10+ years. If you buy a used lens with missing components (cap, hood, etc.), it should be easy to find new and used parts on eBay. The version I purchased can with a Kirk foot and lens support. I am not sure it is really necessary for birding photography, but I can see a utilitiy in landscape photography.Read full review

Happy photographer Buying a used camera lens is always a risky thing to do but in this case the lens was as advertised. looks brand new with no markings of use. The lens glass is clear of dust and scratches. Have used it a couple of time and happy that I purchased this one.

Excellent lens for a great price. Great picture quality. The lens is exceptionally sharp with minimal to no chromatic aberration at all zoom ranges. Its autofocus is fast, accurate, and nearly silent. Most importantly, it is light enough to carry around without strain. It is ideal for bird photography, especially if you have a 1.4x or 2x teleconverter. It was well-priced for being in nearly mint condition. There are minor scratches on the outside and dust on the lens, but the electronics and optics work really well.