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11-14-2013, 05:20 PM   #16
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QuoteOriginally posted by derekkite Quote
I think there is a slight misalignment of the focus screen. If you compare a center line in live view it is off center in the viewfinder.
I just re-checked my K-3 again and compared it with my K-5IIs:

You were right. On my K-3 the focus sensors seem to be shifted upwards with respect to the focus screen/indicators.
On my K-5IIs it is exactly the opposite: The focus sensors are shifted downwards (and slightly to the left) with respect to the focus screen/indicators.

I never experienced any major problems with AF. However, do you think that this misalignment can have negative effects when dealing with very thin DOF? Or with other words: Is this something one should get "fixed" within warranty (if possible)?

Klaus

PS: I dont think that the focus sensors are any smaller than the ones in my K-5IIs. The center focus points cover the same area which is approx. the circular area of the focus screen. I didnīt see a difference between both cams.


Last edited by kdre; 11-14-2013 at 05:29 PM.
11-14-2013, 05:27 PM   #17
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It is just marking on a fresnel lens. As long as it is at the proper angle and distance so that it shows focus accurately, I don't think it is an issue. I won't be sending mine in for that. If there is an issue more pressing I probably would put it on the list of things to adjust.

I haven't tested the focus screen positioning yet, maybe I'll do it this weekend. It seems good on observation so far, but a test with my macro lens may be in order. The autofocus on my body is accurate with a newly calibrated lens.
11-14-2013, 06:38 PM   #18
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Is the f/2.8 af sensor a larger player in this, more so than size? I would think that only the II series with one hi-sensitivity af point would stand a chance compared to the three points of the k-3.
11-15-2013, 03:33 AM   #19
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QuoteOriginally posted by PALADIN85020 Quote
Just got my K-3 yesterday, and have had a small experience with the center dot focus and metering. I was taking an indoor picture of my dog, who was about 7 yards away from me, sleeping on the couch. Using the center spot, I focused the dot on the black area of his head (he has a black and white head), in Av mode. When the picture came up, it was GROSSLY overexposed. I then focused on the white area of his head, and the picture was GROSSLY underexposed. I switched to the full 27-point mode, and the picture was perfect.

The point being that the dot can discern a very small area to focus on and calibrate exposure. If you have light and dark areas in your subject matter, you might want to select a wider area to get a good exposure.

John
Sounds to me like you're doing SPOT metering, or perhaps Centre Weighted.

11-15-2013, 04:08 AM   #20
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Yes, spot metering will meter on a very small spot. Center weighted works well.
11-16-2013, 10:31 AM   #21
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QuoteOriginally posted by dosdan Quote
What have you got Menu C1, item 5, "Link AE and AF Point" set to? The default is "Off".

Dan.
Yes, I have the AE and AF points linked, different than the default. I was used to this arrangement with the K-5 and liked it.

John
11-16-2013, 10:34 AM   #22
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QuoteOriginally posted by bxf Quote
Sounds to me like you're doing SPOT metering, or perhaps Centre Weighted.
Yes, I was using spot metering, linked AE and AF. I have since changed to center weighting to avoid this anomaly.

John
11-17-2013, 11:01 AM   #23
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I was just doing some focus testing of the K-3 versus my old K-5. I'll post a separate topic with my results once I analyze the pictures. But one thing I did notice is that the K-5 is more easily confused when the focus target is small. Where the K-3 would focus confidently on the small target, my K-5 sometimes focus in between the target and the background. So that's a tangible benefit already.

11-17-2013, 10:14 PM   #24
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Looking forward to readiing your findings
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