On Sep 19, 2012, at 1:40 PM, Igor Roshchin wrote: > Larry Colen lrc at red4est.com > Wed Sep 19 15:31:43 EDT 2012 > >> On Sep 19, 2012, at 11:17 AM, Paul Stenquist wrote: >> > > Often suggested technique to deal with those cases is to set the AF to > use the central point. That can be done for centered objects > or for static ones even when they are off center (AF, hold, reframe). > That can work for shooting single musicians who are more steady, and/or > typically are in the middle of the frame. > The problem with that when you are shooting dancing couples is that > in many cases, the central AF point is right between the dancers. > A possible work-around that is that you switch AF to a point that you > choose off center, where you expect one of the two to be. > This is not universal and requires switching (so it is not suitable > if you are trying to shoot several couples within one song), but > it is good, e.g. when you are trying to get a good shot of a particular > couple and taking a series of their shots with simillar framing and > camera orientation.
This is pretty much exactly what I do. >> Beyond that, faster accurate focus in stupid low light would really >> help. Dancers just are not considerate enough to only move >> perpendicular to the line of focus. > > I feel for you Larry! > Those damn dancers! Shoot them! ;-) I had the feeling that you would know exactly what I'm dealing with. And lindy hop, as you know, is even worse than tango or blues. > >> >> One feature that would really help me would be different exposure >> metering modes, one where I could say to not meter on the bright back >> lighting, another, where it would ignore dark backgrounds (though that >> is more a lightroom issue). I mostly just shoot manual exposure >> anyways, but sometimes when people are moving around from light to >> dark areas, I don't have that luxury and have to go to TAv. > > When there is a large variation of the light throughout the frame, > and the camera either cannot cover the full dynamic range, or you > don't care for the extreme parts of it (direct light, dark background > shadows), you can try a very similar technique as described in relation > to AF above: use the central point metering. > I haven't tried it myself yet, but in principle you can couple the > metering and the AF points (in the menu), - and use the same approach > for dancers who are off-center. > You can play with that when not "on assignment". :-) My camera is set to lock AE with AF point. > > >> >> There were also a bunch of pictures that weren't "lost" per se, but >> were rougher than I'd like because in order to have a fast enough >> shutter speed for lindy hop, I was shooting in the ISO 12,800-25,600 >> range. An 8MP sensor with the latest technology would do me more good >> than a 24MP sensor. > > I think you mean that the noise level from a larger pixel is lower. Lower noise, more DR. > I didn't think about it in full depth, but I would assume that > averaging the signal, say, 3 adjacent pixels while downsampling from 24 MP > to 8 MP, if done correctly from the RAW format, should produce close, if > not equivalent result. It might, actually, produce even a better result > under certain conditions (that's my guess only). I think that may work. > But then the question is whether the software you are using (e.g. LR) > is doing a good job in averaging those pixels in a right way in the > process of downsampling. That is an important question. And one I don't know the answer to. > After all, - you see a similar noise-smoothing effect on a 900pxx600px > image, where the noise is not that pronounced. > > >> >> Well done mirrorless technology could alleviate a lot of my problems. >> Without the mirrorbox and needing retrofocus lenses, I could get >> faster wide lenses. When focus is an issue, a sharp 30/1.4 on APS >> would do me more good than a FF 50/1.4. Likewise, for manually >> focusing in the dark, liveview, and I imagine focus peaking , would be >> an immense aid. >> > > I am not sure what you mean by "retrofocus". http://en.wikipedia.org/wiki/Wide-angle_lens If the registration distance is greater than the focal length, you need extra elements to move the focus point back to the sensor (film). > Are you talking about the crop-factor of the lenses on FF and APS? > If that guess is correct, it's just a question of the sensor size on > the mirroless camera, not the fact that it is mirrorless. > I suspect I am just not understanding what you are trying to say here > about the mirrorless. With a mirrorless camera, you don't have to have the rear element far enough from the sensor for the mirror to swing up out of the way. In theory, the rear element could be practically touching the the sensor. This is why my friend Marco has a 25mm f/0.95 lens for his u4/3 camera, and for camera systems based on 35mm SLRs there aren't a lot (any?) really sharp lenses shorter than 30mm and faster than f/1.8, though reasonably sharp 50/1.4 lenses are so common as to have been almost the default. > > > Best, > > Igor > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- Larry Colen l...@red4est.com sent from i4est -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
