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11-07-2011, 01:11 PM   #16
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QuoteOriginally posted by audiobomber Quote
In Av Mode, Auto Ev would change the shutter speed and/or ISO, never the aperture, which is set by the photographer.
You have misunderstood what it does. The manual is not clear, but I just tried it to confirm it still works as I thought:

I set the camera to Av, f/2.8, iso 6400 and pointed it at my ceiling light. I got 8000 flashing, and the shot is overexposed. Then I turned on Auto EV Compensation, and took the same shot. The camera switched to f/9.5, and the shot was not overexposed. Note carefully that it changed the aperture, despite this being aperture priority mode.

Trying the same idea in TAv I set it to f/2.8 1/45, and again the shot is overexposed. This is only as it should be if Auto EV Compensation was off.

The name is certainly stupid. It's possibly not even intended to do this. But in Av it does do this, and in TAv is does not. (It does it stupidly though, in my test it should have changed to ISO. But at least it didn't just let the image be blown out.)

11-07-2011, 01:14 PM   #17
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QuoteOriginally posted by audiobomber Quote
Most people just rotate both wheels simultaneously in opposite directions to maintain exposure. It's very quick and intuitive.
It's harder to be sure you got it right that way. And AE lock works just fine in this situation anyway, it's only when I adjust the ISO (which is also when spinning both wheels at the same time is useless) that it doesn't work.
11-07-2011, 01:24 PM   #18
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Ev compensation just moves the scale of the metering, that's all. When I started shooting digital, Ev compensation confused me greatly, and I see the same confusion among others all the time because it is not explained clearly. The manuals all make it sound like it *does* something -- i.e. makes choices about exposure or shutter speed or magically brightens an image with some mysterious process, etc. But it just shifts the output of the meter up or down, that's it. It is just like shooting a film camera when you set the ASA to something other than the actual rated film speed. The decisions the camera makes based on this modified meter reading will then be altered depending on the mode, but the parameters it works with are the same as with Ev = 0.
11-07-2011, 01:43 PM   #19
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What you say is true, but irrelevant. We are talking about custom function 7, "Auto EV Compensation". Despite the name, it is not actually related to normal EV compensation.

11-07-2011, 01:58 PM   #20
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QuoteOriginally posted by drougge Quote
You have misunderstood what it does. The manual is not clear, but I just tried it to confirm it still works as I thought:

I set the camera to Av, f/2.8, iso 6400 and pointed it at my ceiling light. I got 8000 flashing, and the shot is overexposed. Then I turned on Auto EV Compensation, and took the same shot. The camera switched to f/9.5, and the shot was not overexposed. Note carefully that it changed the aperture, despite this being aperture priority mode.)
OK, but you're artificially making it act weird. You've locked ISO and shutter speed is maxed out, so it moves aperture. I see what you mean though, if it does this in P-mode, why not in TAv mode?

Auto Ev appears to be like Green mode, where it ignores user settings. I've never used Auto Ev and never would. I don't want the camera guessing at what I'm trying to achieve.
11-07-2011, 03:08 PM   #21
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QuoteOriginally posted by audiobomber Quote
OK, but you're artificially making it act weird. You've locked ISO and shutter speed is maxed out, so it moves aperture. I see what you mean though, if it does this in P-mode, why not in TAv mode?
Sure it's a stupid example, but I don't have anything particularly bright to test against. In principle it could happen at base ISO. Having the option of not getting blown out shots just because you weren't paying attention isn't a bad thing. (Note option, noone is forced to turn this on, and I normally wouldn't.)

QuoteOriginally posted by audiobomber Quote
Auto Ev appears to be like Green mode, where it ignores user settings. I've never used Auto Ev and never would. I don't want the camera guessing at what I'm trying to achieve.
It's not like green mode, it would be useful for people who more or less know what they're doing. Example, once again in TAv, which is the mode where I've wanted it:

I like being in control of my DOF, so I set the aperture I want. And then I'm shooting something that moves, so I need a fast shutter speed. To set that as well I can choose TAv or M. Since the light varies, and choose TAv. Then I get a bunch of overexposed shots, because I didn't choose a super fast shutter speed (that would get me a stupidly high ISO for most of the shots). I don't mind at all if I end up with a faster shutter speed than I set, I just don't want slower. TAv with this function working would give me that. Nothing actually gives it. (And nothing that requires me to pay attention to anything but my subject is a valid solution. I shoot mostly in M, when I use the automation it's because I don't have time not to.)

Admittedly what I actually wanted was an Av-mode with user-settable minimum shutter speed, but in practice this would have worked as well. It would maybe have been ok to use Av and set a high-ish ISO. But claiming that this function has no place except for newbies is wrong I think.
11-07-2011, 05:10 PM   #22
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QuoteOriginally posted by drougge Quote
It's not like green mode, it would be useful for people who more or less know what they're doing. Example, once again in TAv, which is the mode where I've wanted it:

I like being in control of my DOF, so I set the aperture I want. And then I'm shooting something that moves, so I need a fast shutter speed. To set that as well I can choose TAv or M. Since the light varies, and choose TAv. Then I get a bunch of overexposed shots, because I didn't choose a super fast shutter speed (that would get me a stupidly high ISO for most of the shots). I don't mind at all if I end up with a faster shutter speed than I set, I just don't want slower. TAv with this function working would give me that. Nothing actually gives it. (And nothing that requires me to pay attention to anything but my subject is a valid solution. I shoot mostly in M, when I use the automation it's because I don't have time not to.)

Admittedly what I actually wanted was an Av-mode with user-settable minimum shutter speed, but in practice this would have worked as well. It would maybe have been ok to use Av and set a high-ish ISO. But claiming that this function has no place except for newbies is wrong I think.
You have exactly described my situation and the need or desire for the "Auto EV Compensation" to work in TAv mode. I feel that it's an advanced feature that certainly didn't exist on and entry level Pentax DSLR I've owned (DL, K100D, Kx).

It appears that it won't work in TAv and that I didn't misunderstand the manual or overlook another related setting. So be it. If it did what it implied, it would be handy.
11-07-2011, 05:26 PM   #23
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QuoteOriginally posted by audiobomber Quote

"Thank you for contacting Pentax.

Auto EV would work in any mode other than Bulb or M.

Normally, a camera tries to balance an image to 18% gray.
With auto-EV the camera looks at the scene and applies EV compensation based what it thinks is supposed to be correct.
It may look at a scene of all snow and think, hey, 18% gray is probably not right for this, lets balance it to a brighter level.
This system is of course imperfect, but can help out a newer photographer to get shots correct more often, or help even an experience photographer who might just be in a hurry.

If you are in need of further assistance, please respond to this email or call our technical support center at 800-877-0155."


https://www.pentaxforums.com/forums/344102-post17.html
That description is not what is described in either the menu or the manual. It also states above that it works in all modes except bulb or manual, but it isn't even available in green mode. In TAv it does absolutely nothing. In fact I can't get it to do anything regardless of mode. No matter what the mode or subject, it meters and exposes exactly the same for a static scene with identical lighting. I guess it's just a useless feature that was put in to make the camera look more advanced.

FWIW, the camera is at FW 1.3.

11-07-2011, 05:26 PM   #24
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Auto Ev does work in TAv mode, as explained by Pentax service, and confirmed in my testing. It works like conventional Ev comp, it tries to adjust exposure in conditions where the photographer would normally compensate. The way you guys are trying to use it is different and not what was intended as far as I can see.
11-07-2011, 05:29 PM   #25
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QuoteOriginally posted by areidjr Quote
No matter what the mode or subject, it meters and exposes exactly the same for a static scene with identical lighting.
Are you shooting a scene that needs Ev compensation? It worked for me in P and TAv modes with backlit subjects, by automatically applying half a stop of compensation.
11-07-2011, 05:30 PM   #26
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QuoteOriginally posted by audiobomber Quote
Auto Ev does work in TAv mode, as explained by Pentax service, and confirmed in my testing. It works like conventional Ev comp, it tries to adjust exposure in conditions where the photographer would normally compensate. The way you guys are trying to use it is different and not what was intended as far as I can see.
With the camera on a tripod with a static subject/scene/lighting it does absolutely nothing in any mode, regardless of whether it's within the metering limits or has reached an extreme. It meters exactly the same on or off.
11-07-2011, 05:44 PM   #27
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QuoteOriginally posted by areidjr Quote
With the camera on a tripod with a static subject/scene/lighting it does absolutely nothing in any mode, regardless of whether it's within the metering limits or has reached an extreme. It meters exactly the same on or off.
I repeat, is it a scene that clearly requires exposure compensation? Shoot a blank piece of paper with Auto Ev on and off. I just did it and it exposed by an extra stop in Auto Ev mode.
11-07-2011, 05:55 PM   #28
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AutoEV is for when the exposure is out of range. In TAv, say you've got the ISO range set to 80-320. If it's overexposed, the ISO can't go any lower than ISO80, so AutoEV should change either shutter speed or aperture to reduce the exposure further. If it's underexposed and ISO320 is still insufficient, then the ISO should be increased past the current set upper ISO limit.

If it's not operating this way, it's not true AutoEV.

Dan.
11-07-2011, 06:00 PM   #29
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QuoteOriginally posted by audiobomber Quote
I repeat, is it a scene that clearly requires exposure compensation? Shoot a blank piece of paper with Auto Ev on and off. I just did it and it exposed by an extra stop in Auto Ev mode.
Then I obviously have a defective camera. It meters the same, on or off, regardless of what I shoot, including a solid white or black target.

I've wasted enough time on this and will just ignore the setting.

EDIT: In another thread you just posted that you don't have a K-5 any longer.

QuoteOriginally posted by audiobomber Quote
I bought a K-5, noticed obvious misfocus in tungsten light. I loaded V1.03 and tested vs. my K-x and K20D, in dim tungsten lighting. Both older cameras focussed perfectly, the K-5 showed no change, severe front focus in tungsten light, perfect focus in natural light. I returned it, I'll wait for the next body.
What camera body are you testing this on?

Last edited by areidjr; 11-07-2011 at 06:17 PM.
11-07-2011, 06:34 PM   #30
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QuoteOriginally posted by areidjr Quote
What camera body are you testing this on?
I'm using a K20D
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