Thanks for the really helpful review, Dustin.
I have been following Sigma's progress in lenses for many years. They have stepped up their range and quality in a relatively brief time, to offer some really great lenses.
Regarding the 50-100mm f/1.8, I'm so glad to hear (aka 'read') that in your experience, Dustin, it autofocuses better than other Sigma / ART lenses. Having both experienced poor autofocus (AF) accuracy and consistency on a few Sigma lenses myself, as well as having read many others report inaccurate and/or inconsistent AF, meant that I have not bought any of their ART lenses to date.
I currently own 2x Sigma UWAs for APS-C: the amazing 8-16mm and the very good 10-20mm. Because AF is not critical for 99.9% of my UWA photos, I often use these lenses in manual focus (MF) or apply hyperfocal distance principles to get the shot I want. I'm particularly very happy with the Sigma 8-16mm which I have used for some years now and is unequalled in its UWA range on APS-C. Love what 8mm can give me (which is an equivalent of 12.8mm on a "FF"/35mm sensor perspective).
The bokeh, sharpness, draw and contrast of Sigma's new 50-100mm are obviously at a very high level. It has a lot going for it, having awesome IQ between 50mm and 100mm is a 'nice' package indeed.
Allow me to make some observations and comparisons with this Sigma 50-100mm f/1.8 ART lens, and some other lenses.
I have used two versions of Sigma's 50-150mm f/2.8 lenses for APS-C, and the larger / OS version is particularly impressive, however 3 things put me off it for me:
- it did not nail focus quite as confidently and accurately as native brand lenses
- the size and weight felt very similar to using a 70-200mm f/2.8 (so if I really wanted a f/2.8 telezoom, I would probably go for a 70-200mm f/2.8 )
- possible issues 'down the track' (e.g. compatibility issues of using it in live view, or with other advanced functionality)
However Sigma's 50-150mm f/2.8 does great as a less expensive telezoom option. In fact, several of my 'official' wedding photos were taken by a friend with the Sigma 50-150mm f/2.8.
The Sigma 50-100mm f/1.8 has certain attractions for me over the Sigma 50-150mm f/2.8, however I would probably still prefer neither as an 'ideal'. I have my Canon 70-300mm L which is such a great, versatile travel zoom - and has that 300mm reach advantage for wildlife and birds which are more my 'focus'. As I do not photograph sports, I have no real need for a fast telezoom.
The size and weight of this 50-100mm lens, though, is somewhat of a 'turn off' for me. My style of low light / portrait photography requires a small, versatile, lens. This lens is really large, and with a 82mm filter it is quite imposing on subject, and with its length and weight, doesn't give me the flexibility I like when shooting portraits (I do have a great 10-stop 82mm ND filter - thanks to Breakthrough Photography).
But perhaps the greatest factor for me, is Sigma's choice not to implement OS (aka Sigma's 'image stabilisation') on this lens. I really find that a lot of my photos 50mm and beyond (particularly from 70mm) really benefit from having IS/OS.
My most used low light lens is actually the 50mm f/1.8 STM, which does a great job for what it's worth. Decent image quality already from f/1.8 and very sharp from f/2.5 onwards. Light, focusses very well (AF on this lens is worlds superior and a totally better / different experience to Canon's 50mm f/1.8 II, of which I had two copies.
The preference I would have for an 'ideal' low light lens is similar to proposed by stpr (welcome, new CR forum member!) Yes, I would use a good quality 35mm - 70mm f/1.8 a lot
. If such a lens was made, was relatively small, lightweight, had fast, accurate, consistent AF and (icing on the cake) was also stabilised that would have my money! Canon, Sigma (& Tamron, and other lens manufacturers...are you listening). I have hope that Sigma MIGHT produce such a lens.
The Sigma 18-35mm f/1.8 and 24-35mm, though I would also hope that their is a way that any 3rd party lenses will be able to maintain full compatibility with Canon's PDAF and any future technology and advances. Reading of certain lenses and accessories from 3rd parties in particular not being compatible with various models of new cameras means I will probably stick to mainly having Canon lenses & accessories. Ok, ideally Canon would come out with an EF-S 35-70mm f/1.6 (!) USM IS ... THAT would be seriously great. Or even without IS, if they build an effective 5-stop, 5-axis IBIS into their next DSLR and (semi-pro) EOM bodies! One can dream, right!
On a final, and side note... the other evening at home (here in Australia) - I looked at one of your video reviews, Dustin. It was of the 80D. I enjoyed watching that (I'm quite impressed with Canon's 80D). So I was glad to read that you were using the 80D for part of the real world testing and review of Sigma's 50-100mm f/1.8 lens.
Well, that's enough from me for now.... regards....