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07-16-2015, 10:26 PM   #16
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Faster lenses have many more benefits than slower counterparts.
True most portrait photos are taken at 2.8-5.6 but..even if you have your aperture set at 5.6 you see through the 1.9 which is brighter to your eye and more accurate in showing the centre of the DOF.
Your FA 43 lens set at 2.8 is usually sharper than a lens whose native wide open is 2.8.
You can use teleconverter without losing AF.

I would recommend not being wary of f5.6 or f8 Try your hand at external flash photography

---------- Post added 07-17-15 at 01:31 AM ----------

QuoteOriginally posted by Lowell Goudge Quote
You have just discovered what is behind the great myth and arguments about fast lenses and full frame camera.

Ultra fast lenses have one principal use only, isolation of the subject dorm the background.

Fill frame proponents argue that they need full frame cameras to make use of the shallow depth of field, BUT, as the OP discovered, it is a very limited use and artistic approach, which can become repetitive and boring after a while.

You don't need full frame, as the OP has demonstrated to isolate one face only when shooting wide open to achieve the effect, and you don't need ultra fast glass. While both may yeild a more dramatic effect. They are not necessary
OP Has nothing to do with FF.

Last edited by Sliver-Surfer; 07-16-2015 at 10:34 PM.
07-16-2015, 10:39 PM   #17
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QuoteOriginally posted by Sliver-Surfer Quote
OP Has nothing to do with FF.
I agree and debated putting an apology d ire toy in my response for moving the topic off the narrow discussion on DOF, because his example about the narrow DOF is exactly the reason most FF proponents use to justify their demand for the full frame camera. It allows one to take full advantage of the ultra thin DOF for artistic purposes, but he has demonstrated quite well that you can achieve the effect without full frame.

No intent to hijack the thread
07-17-2015, 05:34 PM   #18
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QuoteOriginally posted by Zerv Quote
I recently acquired an FA 43 and it has been great thus far, giving me very pleasant and pleasing results that I wasn't getting from my other lenses. However, after taking more and more pictures, I am starting to make some observations about the lens itself and in general.

I took some head and shoulder shots of couples at a bright outdoor event, sitting across the table, about 4-5 feet away at most. The background behind them is quite far, I'd say 300-400 feet. I'm shooting in Av and at f2.8, I took a picture of a couple sitting together, just slightly staggered in distance to me, one shoulder behind another. In other words, their faces were not in the same plane, about 6-7 inches apart. As more experienced shooters probably would have known, the results were the person's face in front who I focused on was sharp but the one slightly behind them was very out of focus.

I tried again, this time at f4. Better, and usable, but person behind was still softer than I would like. I didn't have the opportunity to try again.

Calculating after the fact, at f2.8 I had about 4.5 inches of DOF. At f4, about 6 inches. I probably should have gone with f8 to get both faces in focus.

What I get from this is that with the FA 43, if I am taking head and shoulder shots of couples in a natural setting (unposed and likely not perfectly in plane) at a distance of about 5 feet, I can't go too much larger than f8. Thinking further, it seems like only single person portraits and things I want in focus under 6 inches could use f4 and larger. Increasing distance would help but this isn't always possible. Plus, luckily the background was far away. If there were things or people not far behind them, going to f8 would have not created the separation I wanted.

My question is, does this somewhat render the wider end of this lens with a max of f1.9 impossible to use without backing off quite a bit unless I am shooting for very small in-focus areas? I feel like if I did, I would always be cropping after the fact and I like to compose as shot. If I switch to a longer focal length lens such as an FA 77, this only compounds the problem. If I went shorter such as with a DA 21, it seems like I'd have to get in really close to recreate the shot plus more DOF, less separation. Strictly going by the calculator, it seems my DA 35 from a specifications point of view would have been more appropriate.

In this case, was I just not using the FA 43 as intended? Wide open, I'm getting that you need to be about 9 feet from the subject to get about 1 foot of DOF. This is shedding a somewhat different light on this lens for me. Not good or bad necessarily. Just different than I what I thought this lens was going to be used for. If anything, it definitely gives me more to consider when it's on the camera. And more to consider when choosing my future lenses. This kind of changes what I think about maximum apertures and what I need vs what I want. It's nice to have a large max aperture at your disposal but if it's not used as often and very situational, perhaps the costs may need more consideration.

In saying all this, I think I'm coming to more of an understanding. Am I on the right path or am I thinking about this the wrong way? Any thoughts are appreciated. Thanks!

I think you are overthinking this a little bit. This would happen with any lens. Usually what I do when shooting with a wide aperture and with subjects that are not in the same plane, I switch the lens to manual focus and try to focus somewhere in between the two(or more) planes where my subjects lie. It might not be perfect, but that is about all you can do in that situation, unless you want to use a smaller aperture which would bring the background into focus then blur the back ground in PP.

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