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01-17-2017, 10:19 AM - 4 Likes   #1
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Live view brightness should re-calculate during magnification

This is not a request for a new feature, just a minor fix to how an existing one works.

When using live view to compose/focus a subject on a dark stage, predictable "overexposure" on the LCD becomes an obstacle. Dramatizing with a picture grabbed off google, it goes something like the below.

Suppose you're trying to capture this scene using live view.


Initially what you'll see is this, because the presentation is thrown off by all the dark space.


I understand why that's necessary - exposure can only be so smart, and you probably don't want to complicate the user interface by adding an exposure compensation setting that applies only to live view (although... speaking for myself, that would be awesome). However, the overexposure/"bloom" persists after the user picks a magnification area for critical focus, and it should not. Since the color of the saturation is pure white, it also makes it difficult to use focus peaking.



Apparently what is happening here is that the magnification is a simple-minded crop, where the display level calculations are still based on the whole frame. Correct behavior would be to calculate levels based on what's visible in the current view.


I've struggled with this both on the K-01 and the K-3 ii. In my opinion it's a logical oversight - even though it may affect a small number of users, there is no downside to fixing it, and it would make these cameras into real manual-focus beasts when used with a loupe and fast glass (which is my preferred setup for concert shooting).

Thanks for your consideration.


Last edited by Sluggo; 01-17-2017 at 10:29 AM.
01-17-2017, 03:36 PM   #2
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I should add ... based on discussion in an earlier thread about this, I believe the above applies only to manual exposure mode -- which is what you need to use in live show situations, especially music, where you know the brightness of the spotlights but can't count on the background levels being constant.

In other modes, which allow exposure compensation, the LCD live view reflects that compensation. But when exposing manually, there is no such adjustment, so the camera assumes zero compensation. Again, that would be okay, if it calculated based on the contents of the magnification window instaed of the entire frame.
01-17-2017, 04:09 PM - 1 Like   #3
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In the scenario you present, the use of use spot metering is highly appropriate. The upshot of this is that it would dim the view appropriately in live view. Spot metering and AE lock are a very useful combination.

Last edited by Digitalis; 01-17-2017 at 04:17 PM.
01-17-2017, 05:00 PM - 1 Like   #4
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QuoteOriginally posted by Digitalis Quote
Spot metering and AE lock are a very useful combination.
When manually focusing, spot metering only works in the center of frame, right? Which means relying on the center-focus-recompose method, which gets unreliable at wide apertures as the focus plane moves out of parallel. Besides being just slower procedurally than if you didn't have to recompose. And it should not be necessary to autoexpose at all: in event photography where you've taken just a few chimped test shots to figure out how hot the spotlights are, manual mode gives consistently correct exposures the rest of the night. I appreciate the suggestion, but essentially you're suggesting using an autoexposure mode as a workaround for a shortcoming in the live view system, and that would slow me down and can only hurt exposure consistency.

01-17-2017, 05:28 PM   #5
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QuoteOriginally posted by Sluggo Quote
When manually focusing, spot metering only works in the center of frame, right?
No, only with MF lenses is the center focus point locked. With DA or D-FA lens (don't know about FA lenses) you can select the focus point in all meter, exposure and focus modes.
01-17-2017, 05:44 PM - 1 Like   #6
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QuoteOriginally posted by Not a Number Quote
only with MF lenses is the center focus point locked
My main concert lens is an A*85/1.4. ... edit: and anyway I also just now tried setting the focus point in MF mode using a DA21 lens - the AF point button goes unresponsive when the switch is flipped to manual focus. So just for academic interest, how do you do that?

Last edited by Sluggo; 01-17-2017 at 05:53 PM.
01-17-2017, 09:45 PM   #7
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You're setting the meter mode to Spot and not AF mode to Spot, correct? If you set AF mode to spot it locks the AF point to the center even with DA/F lenses.
01-18-2017, 04:23 AM - 1 Like   #8
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QuoteOriginally posted by Sluggo Quote
essentially you're suggesting using an autoexposure mode as a workaround for a shortcoming in the live view system,
If you are working manually, the green button along with spot metering would be more appropriate, however using Tv with a high shutter speed [as you are dealing with more than just OOF blur] movement blur may need to be controlled as well: So using Tv mode and allowing the camera to select aperture with a fixed ISO could be handy with spot metering and AE lock. It would be quite easy to calculate this in your head for manual control - most people prefer to use the path of least resistance when it comes to establishing correct exposure parameters.

01-18-2017, 04:29 AM - 1 Like   #9
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@NaN: Yes, the metering is set to spot. When AF is switched off, the AF mode entry in the info screen gets grayed out anyway, so I can't very well change the AF mode to anything; also, as mentioned above, the AF point button does nothing when AF is switched off. So again, how are you moving the AF point when AF is off?
02-05-2019, 07:08 AM - 1 Like   #10
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FIXED in K-1 ii body

Let me commit a little forum-necromancy here to happily report: this is fixed in the K-1ii. I had thought so from some experimenting, but last night I did my first concert shoot with it and am sure. The combination of manual exposure, manual focus, and live view no longer results in the "automatic gain control" effect; a spot-lit subject in front of a dark background no longer blooms and loses detail in live view. Rather, the selected shutter/aperture/ISO is taken into account to create a nearly perfect live preview that is easy to use with focus peaking, at least for A-type lenses.

While it would be flippin' awesome if the fix were also made available in firmware for the K-3ii and other affected bodies, I'm at the point now where full frame is pretty clearly my way going forward, and from the tone of the discussion above, I think it unlikely that many other users had been impacted. Maybe it had only been me who insisted on shooting that way and exposing such an obscure bug.

If you happen to be a Ricoh engineer who noticed this thread two years ago and said "oh, I know why that is happening" -- thank you.
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