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03-24-2009, 10:05 PM   #31
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I realized early the red focus point indicators were very distracting - my brain was telling me red = on focus, which is not at all the case. I also found my nose was switching the autofocus point, so I set it for center only.

With the camera on center focus, you always know where the focus point is supposed to be.

03-25-2009, 05:48 AM   #32
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QuoteOriginally posted by FHPhotographer Quote
can't figure out a way to get a couple of hundred points onto a viewfinder screen and get those points to light up the actual AF spot rather than a general "you guess where it is within this area" point.
Even a DSLR with 51 AF points can't tell you the exact spot, it can only tell you which sensor out of the 51 contains that spot. If you want that then you have to forget using a DSLR. Buy a bridge or hybrid camera with EVF, problem solved.
You have to accept the technical and practical limitations of a system or just use a different one which suits your needs and expectations better.
03-25-2009, 01:53 PM   #33
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QuoteOriginally posted by FHPhotographer Quote
I get the difference between the VF analog view and the LCD digital view, but still and all despite my technical ignorance, I'm dubious that a company that can cram 14.2 million pixel photosites plus microlenses onto a sensor smaller than a postage stamp can't figure out a way to get a couple of hundred points onto a viewfinder screen and get those points to light up the actual AF spot rather than a general "you guess where it is within this area" point.
You're right, that might be technically feasible. Might drive the cost up, too, though, and for a feature that probably won't interest most photographers, it might not get very high priority.

Also, it occurs to me that we don't know that much much about how the AF sensor works, but it seems entirely possible to me that it is not actually looking at just one tiny spot it could isolate, but instead trying to come up with "average" phase difference for the entire area covered by the sensor. Or something like that it. That is, you're assuming an AF sensor capable of identifying a specific area within its field of viewing and recognizing that this is the area it is is actually using, when it might not be that smart.
03-25-2009, 04:36 PM   #34
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I disagree, with humility (I hope)

QuoteOriginally posted by simico Quote
Even a DSLR with 51 AF points can't tell you the exact spot, it can only tell you which sensor out of the 51 contains that spot. If you want that then you have to forget using a DSLR. Buy a bridge or hybrid camera with EVF, problem solved.
You have to accept the technical and practical limitations of a system or just use a different one which suits your needs and expectations better.
Well, it looks like I'm going to swim upstream on this. I believe (notice please that I didn't state this as a fact) this could be done and done fairly easily. It we accept it can't be done, and take the manufacturer's word on the great mystery of the process, then it won't be done. I've used the term Hobson's Choice before, because it really means no choice at all; take it or leave it. I believe we are acquiescing to the manufacturers and accepting their delivered truth and it won't change until we stop buying (literally and figuratively) into their position. Or so it seems to me,
Brian

03-25-2009, 04:38 PM   #35
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The problem with turning off the red spot is not knowing when you've accidently changed spots? Happened to me more than once.

The beep means "focussed", yes?
03-25-2009, 07:15 PM   #36
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I can't see why you couldn't have the actual AF response area shown or even red arrows pointing to the future (predicted) AF point in predictive/tracking AF. It would require either an EVM or LCD transmissve (overlay) screen within the optical viewefinder. Whether or not it would be useful or confusing is another question.

Dan.
03-25-2009, 09:27 PM   #37
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QuoteOriginally posted by Arpe Quote
The problem with turning off the red spot is not knowing when you've accidently changed spots? Happened to me more than once.

The beep means "focussed", yes?
The beep means focused, but the red spot doesn't not. I turn it off, but only when I set it for center focus. And that's where it remains 99% of the time. The only time it leaves that position is when I'm setting up a shot with a tripod and would like to focus somewhere other than the center (can't exactly say it's easy to focus then recompose when a tripod is involved).

So in my case, I set it for always center focus, red spot off, and beep off. Beeps make people look - No beeps!
03-25-2009, 10:44 PM   #38
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QuoteOriginally posted by FHPhotographer Quote
Well, it looks like I'm going to swim upstream on this. I believe (notice please that I didn't state this as a fact) this could be done and done fairly easily.
To the best of my knowledge, the red LED lights are actually located in the AF module below the mirror, nestled in with the AF sensors themselves (if anyone knows different then please tell me).

Assuming this to be true, the LEDs CAN'T indicate the exact focus point because then they'd be in FRONT of the AF sensor, preventing it from doing it's job.

03-25-2009, 10:50 PM   #39
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QuoteOriginally posted by dosdan Quote
I can't see why you couldn't have the actual AF response area shown or even red arrows pointing to the future (predicted) AF point in predictive/tracking AF. It would require either an EVM or LCD transmissve (overlay) screen within the optical viewefinder. Whether or not it would be useful or confusing is another question.
I have two comments about this:

1) Yeah, it would be confusing. I gotta believe that in a situation where you'd want predictive tracking, paying attention to little red lights going on and off in the viewfinder is going to do more harm than good.

2) LCD screens rely on polarizers - even a "transparent" LCD would cut viewfinder brightness by at least half. I think a lot more people would be turned off by the reduction in brightness than turned on by the additional information.

I haven't heard of "EVM" - what's that?
03-25-2009, 11:20 PM   #40
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QuoteOriginally posted by Sean Nelson Quote
I haven't heard of "EVM" - what's that?
I meant EVF. (We sell an EVM product so I've got those initials on my mind.)

Dan.
03-26-2009, 02:42 AM   #41
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QuoteOriginally posted by dosdan Quote
It would require either an EVM or LCD transmissve (overlay) screen within the optical viewefinder.
Sorry, but what's the point of an EVF in an optical VF? That doesn't really make sense imo. You either have EVF or OVF, by mixing them you just get the disadvantages of both. I bet nobody wants even darker viewfinders with inferior quality...
03-26-2009, 02:45 AM   #42
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QuoteOriginally posted by FHPhotographer Quote
I believe (notice please that I didn't state this as a fact) this could be done and done fairly easily. It we accept it can't be done, and take the manufacturer's word on the great mystery of the process, then it won't be done.
You have your right to beleive whatever you want. I don't take the manufacturer's word, instead I use my engineering knowledge as well as my little knowledge about cameras and some common sense.
03-26-2009, 02:50 AM   #43
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QuoteOriginally posted by Sean Nelson Quote
To the best of my knowledge, the red LED lights are actually located in the AF module below the mirror, nestled in with the AF sensors themselves (if anyone knows different then please tell me).
As far as I know the leds are in the pentaprism/pentamirror box and their light is projected to the matte (focusing) screen. Another reason why totally precise indication of focus spot is not possible in a DSLR's optical viewfinder; neither the focusing screen, nor the LEDs can be aligned with 100% accuracy to the AF sensors at the bottom of the body (or to the imaging sensor at the back of the body).
03-26-2009, 08:23 AM   #44
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QuoteOriginally posted by simico Quote
You have your right to beleive whatever you want. I don't take the manufacturer's word, instead I use my engineering knowledge as well as my little knowledge about cameras and some common sense.
Same here. As I said before, I'm betting the AF system is incapable of even determining exactly where the point of sharpest focus is. But even if it were possible, the technology to light the viewfinder at exactly that spot is probably more trouble than it is is worth. I'm sure Brian is right that it would be *possible* (*if* the information is even available, and again I'm guessing it isn't), but the question is, at what cost and for what benefit.

In any case, not really much point in debating this. The feautre is not there on any camera I've ever seen or heard of, so I wouldn't be expecting it any time soon. Might as well just learn how to best use the tools we have.

Last edited by Marc Sabatella; 03-26-2009 at 02:22 PM.
03-26-2009, 11:21 AM   #45
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QuoteOriginally posted by Marc Sabatella Quote
In any case..... Might as well just learn how to best use the tools we have.
Well spoken again Marc. Kinda back to the original purpose of this thread. I'm far from an expert but I just thought my own experience would help many of us better understand the way our cameras worked, and possibly save a lot of "BF/FF" diagnostic headaches.
Paul
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