Back in the day I bought a massive Sigma 150-500 mm f 5-6.3 telephoto zoom lens to help me with a project I was working on to help create nesting habitat for a locally endangered bird, the common tern. The lens was there to help document the project and help identify the birds. My Sony 75- 300mm was not providing enough magnification for me. I had no chance of affording a 400 to 500mm prime lens, so this was probably the best option at the time.
I was worried the image quality of this lens was not going to be very good, even for my limited use but after taking some photos on a sunny day I was pleasantly surprised. The images were sharp enough for me, and the autofocus was faster than expected. The lens also appeared better built than I expected.
The problem with this lens is really just how practical it was. I used it very little due to its size and weight. This isn’t a lens you can casually put into your backpack just in case you see a wolf. You have to be out looking for wolves and bring a 24mm. in case the light hits the landscape just right, you don’t want to miss that moment.
You can still find the Sigma 150-500mm F5-6.3 on Amazon. Or you can find them used on eBay.
All photos in this post are uncropped and taken with a Sony A65 slt dslr.