Dennis Ernst's reviews
9 out of 10 points and recommendedVery sharp, solid build, smooth bokeh, cost effectiveSlow auto focus, heavy
I spent a good deal of time reading reviews before I purchased this lens. It proved to be an excellent choice. I get very positive comments on work I've done with this lens.reviewed April 25th, 2011 (purchased for $650)
It is built like a tank and is both solid but also a bit heavy. After 3 years of use it shows now wear nor has developed any issues.
The longer working distance is very helpful in working with live subjects in the field. It also gives you just a little more focus distance too.
The auto focus is slow. Most long macro lens are. This was not an issue for me as I use manual focus anyway. The Canon version of this lens is a bit faster but now what I would call fast either.
I shoot this with a canon camera and I've found it to be a very sharp lens. People always remark about how sharp, how much detail and color I get with this lens.
As I'm using manual focus a solid tripod is very important. I have shot it hand held but it is a bit heavy for much of that. It really shines when you the effort to use a solid tripod, mirror lock up and a remote shutter release or timer. If the lens is rock solid still, you'll be amazed and the detail you can get. The focus ring is very smooth and is fine enough to allow you to very precisely choose your focal plane. I have used the autofocus features but you want to make sure you have a single focus point and you have put it exactly in the middle of the area you want in focus. As the focal plane get very narrow I love to use the manual focus so I can choose exactly what element will be razor sharp.
I've shot this lens right along side others shooting the Canon and Tamron 180's, and usually at the end of the day when we compare shots,we'll all pick the work I've done with this lens. The only advantage I've seen with the Canon is that it has a bit faster auto focus. If you are shooting butterflies in flight that may be important but it comes at twice the price.
I purchased this lens before the Sigma 150 hit the market or I might have chosen it for it's smaller lighter build. That's not to say I would trade it now as I've very spoiled with the remarkable results I get with it.
I do have the Sigma 2x teleconverter that I use occasionally. This is a nice combination and produces very good result if you need a little more magnification. I can see a very slight degradation in image quality but nothing more that what you would expect from any brand. This is right on the edge of being able to notice it at all. Of course the higher magnification requires even better technique to make sure everything is absolutely still.
I am very pleased with this lens and recommend it to anyone look for a cost effective alternative to the Canon 180.