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11-21-2008, 10:27 PM   #16
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QuoteOriginally posted by kerrowdown Quote
My vote is with the Katzeye with the optibrite treatment, works great on the K10D, so I guess it would be good for K20D to.
Yeah maybe when I have money to spend for it, I'd rather spend my $150 for other things at the moment

11-21-2008, 10:28 PM   #17
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QuoteOriginally posted by stevebrot Quote
Marc Sabatella put me on to the link below:

Manual Focus with AF DSLRs

While the topic of the Web page is not directly related to viewfinder brightness, the authors make an interesting assertion. For the camera they tested, the viewfinder had the same brightness from for anything larger than f/4.

"...Even though the lens was stopped down a full three stops from f/1.4 to f/4.0, the screen brightness only changed slightly with a small visible difference only appearing after the change from f/2.8 to f/4.0. The background measurement changed from an average reading of 215 to 203 using Photoshop's picker. That works out to less than a third of a stop in brightness change when I compare it to a Stouffer 4110 transmissive step wedge image take with the C7070. A 1/3 step in the Stouffer image at an image value of around 215 shows up as a numerical value change of more than 15. Since most DSLRs meter from the focus screen, it is easy to see how using a fast lens can give exposure problems as well..."

Apparently, some focus screens "eat" light.

Steve
I read that too, that was quite interesting. Thanks Steve.

Diego
11-21-2008, 11:11 PM   #18
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QuoteOriginally posted by the_int21h Quote
I'm not sure if the focusing screen can make it brighter, but I have heard that split screens throw off the metering and focusing in the camera.

-Brian
The split screen only throws off spot metering. The other metering modes are not affected.

The screen has no impact on autofocus whatsoever.

If mounted correctly the screen will not impair manual focus.
11-21-2008, 11:12 PM   #19
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I wonder how it'll "feel" autofocusing with the split screen. I can't wait to get mine.

11-22-2008, 12:24 AM   #20
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QuoteOriginally posted by soccerjoe5 Quote
I wonder how it'll "feel" autofocusing with the split screen. I can't wait to get mine.
It'll be just like using your ME Super. Only with a tiny viewfinder.
11-22-2008, 12:02 PM   #21
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QuoteOriginally posted by stevebrot Quote
"...Even though the lens was stopped down a full three stops from f/1.4 to f/4.0, the screen brightness only changed slightly with a small visible difference only appearing after the change from f/2.8 to f/4.0. The background measurement changed from an average reading of 215 to 203 using Photoshop's picker. That works out to less than a third of a stop in brightness change when I compare it to a Stouffer 4110 transmissive step wedge image take with the C7070. A 1/3 step in the Stouffer image at an image value of around 215 shows up as a numerical value change of more than 15. Since most DSLRs meter from the focus screen, it is easy to see how using a fast lens can give exposure problems as well..."

Apparently, some focus screens "eat" light.
I'm guessing this is the exact same phenomenon I was referring to earlier regarding how the viewfinder lies about DOF (showing more in focus at large apertures than will actually be in focus when you take the shot).
11-22-2008, 05:44 PM   #22
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Given equal speed lenses, I think you'd see roughly similar viewfinder performance between the K20D and the D300. The linked article is interesting on an academic level, but only looked at one camera, which is not exactly known for having a large or bright viewfinder.

It is obvious to some, but I'm not sure if the OP realizes - comparing the K20D to a film camera is not fair because of the smaller APS-C sensor size, versus the large "full frame" 35mm film. The viewfinder must be "cropped" just like the sensor is, otherwise you'd see a lot of things that wouldn't be captured by the sensor.
11-23-2008, 09:43 AM   #23
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QuoteOriginally posted by Groucho Quote
Given equal speed lenses, I think you'd see roughly similar viewfinder performance between the K20D and the D300. The linked article is interesting on an academic level, but only looked at one camera, which is not exactly known for having a large or bright viewfinder.

It is obvious to some, but I'm not sure if the OP realizes - comparing the K20D to a film camera is not fair because of the smaller APS-C sensor size, versus the large "full frame" 35mm film. The viewfinder must be "cropped" just like the sensor is, otherwise you'd see a lot of things that wouldn't be captured by the sensor.
Um yeah I know it's not a fair comparison. I also know that I was comparing the D300 and the K20D when the D300 costs more.

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