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12-10-2013, 03:13 PM   #16
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QuoteOriginally posted by lister6520 Quote
Anyone recognise what it is ?
The back side of a digital camera sensor? It looks to me like it overheated.

12-10-2013, 03:38 PM   #17
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QuoteOriginally posted by RGlasel Quote
The back side of a digital camera sensor? It looks to me like it overheated.
No. Clue: it is made by Canon, or at least they put their name on it.
12-10-2013, 09:12 PM   #18
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AF sensor?
12-11-2013, 04:18 AM   #19
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Thanks, folks, for the input re the AF. I have played around a little with the AF Fine Adjustment and, for a FL of 35mm, found a point (-3) where PDAF and CAF produce very similar images. Obviously, for other FLs, a different value may be required... but I don't think I will go there: if I compare the output of the K-50 in 12MP with the X-10 (which is maxing out at 12MP), the K-50 is clearly producing sharper images.
At any rate, I am not normally a pixel peeper... but with a new cam, some peeping is surely not a bad thing;-)

NFSCD: I am still a little puzzled as to what the fallback strategy is when the LiveView CAF is set to Face Detect mode. Of course the K-50 does focus even if there are no faces around -- but the focus rectangle can be anywhere on screen and it's often not where I would expect it to be, making controlling the actual focus area somewhat difficult in FD mode. Either the firmware sees faces where there are none (at least for me) or there's some other magic working. For the time being I think I'll go with spot CAF.

Beautiful weather here in S England, so I am off to take some RL shots, not only synthetic AF adjustment images! I shall return...

12-11-2013, 01:06 PM   #20
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QuoteOriginally posted by Giklab Quote
AF sensor?
nope.

Clue: it is disposable.
12-11-2013, 01:10 PM   #21
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QuoteOriginally posted by BorrowedTime Quote
...
NFSCD: I am still a little puzzled as to what the fallback strategy is when the LiveView CAF is set to Face Detect mode. Of course the K-50 does focus even if there are no faces around -- but the focus rectangle can be anywhere on screen and it's often not where I would expect it to be, making controlling the actual focus area somewhat difficult in FD mode. Either the firmware sees faces where there are none (at least for me) or there's some other magic working. For the time being I think I'll go with spot CAF.

...
As far as I can tell it falls back to the 'Auto multiple AF points' if it finds no faces. I'm not sure that answers the question though as I never quite understood the logic of the automatic focus point selection, neither with live view nor with viewfinder. I have never had any good luck with it.

The face detection I have used some times, for family occasions and such where it can be a real help when you need to snap shots quickly without having time to think.
12-11-2013, 01:49 PM   #22
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QuoteOriginally posted by lister6520 Quote
nope.

Clue: it is disposable.
Hmm... RAM? Not really disposable.
Memory card? Not disposable either, and a bit odd shape.
555 chip?
Is the black stuff around the circuits the gunk used to cover chips?
12-11-2013, 02:01 PM   #23
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inkjet printer head??

12-11-2013, 02:03 PM   #24
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QuoteOriginally posted by link81 Quote
inkjet printer head??
You got it !


The black stains are ink.
12-11-2013, 02:13 PM   #25
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QuoteOriginally posted by lister6520 Quote
You got it !


The black stains are ink.

yaay!! whats my prize? a brand new silver k3 with full ltd collection??
12-11-2013, 02:24 PM   #26
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WOHOOO

Wouldn't have ever thought of that.
12-12-2013, 06:53 AM   #27
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QuoteOriginally posted by lister6520 Quote
As far as I can tell it falls back to the 'Auto multiple AF points' if it finds no faces. I'm not sure that answers the question though as I never quite understood the logic of the automatic focus point selection, neither with live view nor with viewfinder. I have never had any good luck with it.
Yeah, that about sums up my current thinking. I'll leave AF metering on centre spot for the time being (but it's early days for me, dSLR-wise, so we'll see).
I'm not a great fan of Auto-Whatever and for a long time I resisted using any Face Detection. The X10 changed that as its AF system was quick and accurate with identifying faces and if there were none it would simply fall back to spot AF.

I've now taken my first shots in the wild and so far it looks good; attaching a shot from yesterday afternoon. (I also include a 100% crop.)

However, there's now another thing that's bugging me. Under controlled circumstances (on tripod, fixed indoor lighting, ISO100) I'd (naively...?) expect to get much the same shutter/aperture combination via viewfinder or LiveView (with all other camera settings, lighting etc staying the same). What I do get though is that the K-50 consistently underexposes by between a 1/3 and half a stop when using the viewfinder (ie VF gets me 1/30 F/4.5; LV 1/25 F/4.5 or, with changed lighting, VF 1/4 F/5.6; LF 0.3" F/5.6). Incidentally, this doesn't seem to happen when I shoot outdoors (though of course the lighting is not really fixed there).

Is this to be expected and if so, why?
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12-12-2013, 07:53 AM   #28
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QuoteOriginally posted by BorrowedTime Quote
Yeah, that about sums up my current thinking. I'll leave AF metering on centre spot for the time being (but it's early days for me, dSLR-wise, so we'll see).
I'm not a great fan of Auto-Whatever and for a long time I resisted using any Face Detection. The X10 changed that as its AF system was quick and accurate with identifying faces and if there were none it would simply fall back to spot AF.

I've now taken my first shots in the wild and so far it looks good; attaching a shot from yesterday afternoon. (I also include a 100% crop.)

However, there's now another thing that's bugging me. Under controlled circumstances (on tripod, fixed indoor lighting, ISO100) I'd (naively...?) expect to get much the same shutter/aperture combination via viewfinder or LiveView (with all other camera settings, lighting etc staying the same). What I do get though is that the K-50 consistently underexposes by between a 1/3 and half a stop when using the viewfinder (ie VF gets me 1/30 F/4.5; LV 1/25 F/4.5 or, with changed lighting, VF 1/4 F/5.6; LF 0.3" F/5.6). Incidentally, this doesn't seem to happen when I shoot outdoors (though of course the lighting is not really fixed there).

Is this to be expected and if so, why?
Two factors that could be influencing the exposure differences:

1) Viewfinder (PDAF) metering is from a separate module whereas Live View (CDAF) metering is direct from the imaging sensor. To get them close, make sure you have selected the same type for each (mufti-pattern, center weighted, or spot) but keep in mind that still won't mean they are using the same module.

2) Viewfinder metering can be thrown off by light entering the viewfinder itself. When using a tripod, put the viewfinder cover on or at least put your finger over it to keep excess stray light out.

Hope that helps.
12-12-2013, 09:53 AM   #29
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QuoteOriginally posted by IchabodCrane Quote
1) Viewfinder (PDAF) metering is from a separate module whereas Live View (CDAF) metering is direct from the imaging sensor. To get them close, make sure you have selected the same type for each (mufti-pattern, center weighted, or spot) but keep in mind that still won't mean they are using the same module.

2) Viewfinder metering can be thrown off by light entering the viewfinder itself. When using a tripod, put the viewfinder cover on or at least put your finger over it to keep excess stray light out.
I know about the effects of light entering via the viewfinder and, for these measurements, made sure that the viewfinder was covered, so I assume what I observe has something to do with #1.

OTOH, there seems to be only one AE Metering setting (last option in 1st Recording screen) which presumably is covers both VF and LV. Or am I missing something here?

It's a really strange effect as I do not observe this with brighter outdoor light, only with relatively low-levels of indoor lighting. (BTW, WB and all that is identical.)

Last edited by BorrowedTime; 12-12-2013 at 10:07 AM.
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