I purchased the bargain-priced Minolta 70-210mm f4 ‘beer can’ lens this past Spring for a ‘proof of concept’, possibly as a step toward purchasing the (not-so-bargain-priced) Sony G 70-200mm f4.
I don’t shoot indoor sports. And with the ability to push the ISO on modern cameras, I’m really not concerned about getting the shutter speeds I need using the f4 zoom.
What did concern me was the difference in bokeh, or subject isolation, between a 70-200 f2.8 and 70-200 f4.
I’ve taken many shots using my Nikon 80-200mm f2.8, and looking at the exif data of the images where I truly needed isolation revealed that most where shot at f3.5… or f3.2. Some at f2.8. But practically none were taken at f4 or greater! That certainly caused me some concern, and, as you can imagine, raised the question in my mind ‘would f4 provide enough isolation?’
Of course, I could have tested this simply by using my D700 and 80-200mm, set at f4. I still have (and love) my Nikon kit. But I really wanted to see what the Sony had to offer by comparison. So I picked-up the Minolta 70-210mm f4 off of eBay to use with my A7 and LA-EA4 adapter.
Next, it was simply a matter of waiting for the right event.
The ‘right’ event to test this set-up would be one where:
1) I’m more-or-less stuck in position and unable to easily re-position myself
2) The ability to control my subject’s position would also be out of my control (both of these factors limiting my ability to ‘manipulate the scene’)
3) There were ‘messy backgrounds’ which would truly need to be eliminated
As it turned out this summer was a particularly busy one, and I was unable to attend a couple events I had planned to photograph. It wasn’t until this October that an ideal opportunity presented itself: ‘The 2014 Toronto Zombie Walk”
Prior to the parade I’d be able to move freely, and pose subjects without issue. I’d need isolation, but I’d have a moderate degree of control over positioning. But I’d also want shots of the parade – and that’s where I’d be much more limited in my ability to ‘manipulate the scene’. No doubt there would be people, general crowd, street signs, store-fronts, etc. that I would want to ‘bokeh-out’. With the parade being on a relatively narrow field (the street) and with crowds and buildings just slightly beyond that (on the opposing sidewalk) the camera-to-subject-to-background distances were absolutely perfect, offering a true challenge for the 70-200mm f4’s subject isolation ability.
So… how did it do???
The first set of photos below were at the gathering, before the parade began, and where I had some degree of freedom of movement and was able to have the zombies pose.
I can say that here (as expected) there was no issue what-so-ever, and good subject isolation was easily attainable – especially when filling the frame and cropping-in tightly. What was a surprise though was the quality of the bokeh, and rendering from this very inexpensive lens. I’m quite impressed with it, and it really has me questioning whether the more expensive Sony G is really necessary (in my case).
But of course, as noted, the real challenge would be the parade (or more ‘candid’ shots in general):
Looking at the parade/candid shots you’ll see I wasn’t always able (or willing) to fill the frame – and therefore relied more on the DoF to provide isolation (note: I used the 70-210mm f4 on the A6000, rather than the A7, to provide extra reach. All shots in this posting were taken with the A6000, with the 70-210mm f4, at f4 or f4.5). Where I was able to get a good subject distance, the bokeh is quite nice!
Where the subject is a little further out, or where the background is messier, I can in fact detect a difference in the amount of isolation provided by f4 (than what my f2.8 would have provided). I don’t, however, feel that it is significant. People and shapes are de-emphasized nicely in this scenario, just not as much as they would be at f2.8. The fact that the DoF would be different is obvious (and numbers can be found via DoF Calculator) – but what wasn’t clear to me is whether it would be notably, visually significant. Now I know. To me, it’s not.
So… will f4 suffice in place of f2.8? I think using the f4 lens will require a little more care; a little more attention to background when possible, or, when not, maybe a few less keepers. Maybe. But f4 is certainly very, very viable. Considering the size and weight difference in the lenses, I personally consider it a very worth-while trade.
If you shoot indoor sport, perhaps you need f2.8. If your lively-hood comes from shooting events where you can’t manipulate the scene then you might consider taking along the f2.8.
As for me? I say… ‘F4 and be there!’