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 Re: Pre-order: Sigma 24mm f/3.5, 35mm f/2 and 65mm f/2 DG DN lenses | |
tsdevine wrote:
For my shooting, I can live with AF-S for the 45mm. So far, it seems pretty reliable. I wonder whether it's solely Sigma's fault on this, or whether Sony has a part in as well, anyone know? If it truly is an issue due to undercorrected SA, then I would expect L mount bodies to have an issue as well, any. If they don't, it may be more than just a Sigma problem.
Sometime this forum seems like a rag fest. Samyang may focus better, but after 5 copies I couldn't get a centered 35/2.8, I literally gave up. Different people have different priorities, which is fine, lots of choices.
If the 35/65 floats your boat, that's great, I'm interested as well. Having these options is a good thing....almost too much of a good thing.
-Tim
goldb wrote:
RustyBug wrote:
chez wrote:
As long as it can lock on and track eyes...if not it's a failure for what so many use this lens for.
Isn't that a function of the camera, moreover than the lens?
Granted, the speed of which the glass can be moved may be reliant on the gearing or method for moving the glass.
Spend the money on glass or gears (linear motors, double motor, triple motor) ... you want great from both, more money. So, if one is trying to isolate to AF performance for a price point, did it compromise somewhere else (build, optics, handling) to retain that price point.
Isolating to a single attribute can be an exercise in the "shell game", if one isn't considerate of the whole.
I just don't expect to get top tier of "everything I want" ... in a mid-curve product.
From what I've read / seen, the 45mm isn't just "not great" at AFC. It is positively bad; worse than budget offerings like samyang. Seems likely a function of software/processing rather than the ability to physically move the glass fast enough but I'll leave that to others to determine.
Clearly the 45 has a following here due to the rendering, but poor close-up performance, relatively small aperture, plus bad AFC is a recipe for very limited appeal IMO. I'm glad sigma went with a more well-rounded performer with the 35/65.
+1.
As I mentioned, it focus fine with both AFS and AFC on SL2. For scientifically define this problem, we need specify out of focus scenarios, what is the speed and distance of subject moving? is it just out of focus in AFC even for stationary subject? or It is just can't keep with Camera or Lens. For Sony, most likely is the lens can't keep up, for Leica, it is most like Camera can't keep up. CDAF generally having problem with AFC, the view kind of jittery during action,(because it is a feedback system that require back and forth comparison instead of PDAF, a open loop system) and if either camera or lens not fast enough, you get out of focus images. I understand that before I get SL2 or FP or RX1 for that matter.
For me, I don't use this lens track my dog or kids running toward me, or capture moving human subject close range in street, so it doesn't bother me. Do I wish it can do all, yes, but it will most likely lose its charming if it is able to do it all. I have learned that expect a tool to do it all will only lead disappointment. That is why we either buy more tools to cover different need or buy something fit your priority and live with tradeoffs. my 2c.
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