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10-07-2009, 12:21 AM   #1
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K-7 and shutter speeds in P

In "Hyper-Program" mode (P mode with Custom function 22 set to default) you should be able to select any shutter speed with the front e-dial (or with the rear dial, if CF 22 is set to 2). With the K7 and Auto-ISO enabled, however, you can select faster speeds as you wish, but when you try to select a lower speed, it will jump to some fixed f-number (!). With the DA40 e.g. it will always jump to f/4 and the corresponding shutter speed. In low light it will first decrease ISO, but when it reaches ISO 100 (or your selected minimum ISO), the same jump will happen and it is not possible to select a slower shutter speed.

This is really odd and seems to be a firmware bug. Hasn't anybody noticed this before?


Last edited by matthis; 10-07-2009 at 02:22 AM.
10-07-2009, 12:41 AM   #2
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There's a setting in the menu (custom function?) that automatically adjusts exposure to be "correct" even when you try to adjust it to something you want. Maybe you have that set and it's interfering?

Just a guess.
10-07-2009, 12:58 AM   #3
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QuoteOriginally posted by Arpe Quote
There's a setting in the menu (custom function?) that automatically adjusts exposure to be "correct" even when you try to adjust it to something you want. Maybe you have that set and it's interfering?

Just a guess.
You refer to CF 9 which had also been my first thought. But no, it doesn't make any difference.
BTW, even if CF 9 was ON, the behavior should not that way. CF 9 should only interfere with shutter speeds or f-numbers which do not allow for a correct exposure. That is not the problem, however.
10-07-2009, 01:47 AM   #4
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Mmmmh, do you have the program line option set to MTF?
This could explain why it tries to use the "best" aperture when you set the shutter speed.

10-07-2009, 02:21 AM   #5
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QuoteOriginally posted by dlacouture Quote
Mmmmh, do you have the program line option set to MTF?
This could explain why it tries to use the "best" aperture when you set the shutter speed.
No, had it in "Normal" first, but tried also MTF and "Fast". The program line has no influence on this odd behavior. Anyway, the HyperTv function is designed to override the program line, so the program line should be completely irrelevant.
10-07-2009, 07:47 AM   #6
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Actually, when in HyTv with AutoIso, I'd not be surprised that the aperture selected by the camera follows the program line...
What else??? It has to set two parameters, so it has to follow some logic...

"Fast" is moot when in HyperTv (you already have the control over the shutter speed!), so it must revert to something else...
I'm sure that "DOF (shallow)" does not show this behavior...
10-07-2009, 08:25 AM   #7
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QuoteOriginally posted by dlacouture Quote
Actually, when in HyTv with AutoIso, I'd not be surprised that the aperture selected by the camera follows the program line...
What else??? It has to set two parameters, so it has to follow some logic...
The problem is rather that the camera does not give the shutter speed I want to select. E.g. from 1/250" f/8 (selected by program line) it goes to 1/1000" f/4 instead of 1/180" f/9.5. (Or with less light, to 1/350" f/4 - but always f/4!?)

I am discussing that also on a german speaking forum. Some users have confirmed the issue while others have not. We are investigating further...
QuoteOriginally posted by dlacouture Quote
"Fast" is moot when in HyperTv (you already have the control over the shutter speed!)
No you don't. You have the control (or should have it) over the shutter speed when you turn the e-dial, regardless of which program line is selected.
10-07-2009, 12:58 PM   #8
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Try this:
Put a fast lens on your K-7. (<= f/2.8)
Select mode P with Hyper-Program. (CF 22 value 1 or 2)
Set Auto-ISO to 100-6400.
Point the camera to a subject bright enough to read ISO 100 (still in Auto-ISO).
Activate Hyper-Tv mode by turning the corresponding e-dial.
You will not be able to select slower shutter speeds than the one giving an aperture of f/2.8. I. e., Hyper-Tv will be restricted to very fast shutter speeds.

10-07-2009, 01:36 PM   #9
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I've made this test (without having read your post here!) and on my k7, the aperture stays at f/1.4...
Now, I've set Auto-iso to "Slow", and Program line to "DOF (shallow)", so maybe that's it?
10-08-2009, 01:17 AM   #10
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QuoteOriginally posted by dlacouture Quote
I've made this test (without having read your post here!) and on my k7, the aperture stays at f/1.4...
Now, I've set Auto-iso to "Slow", and Program line to "DOF (shallow)", so maybe that's it?
I still can't find any influence neither of the Auto-ISO slow/normal/fast setting nor of the program line.

However, on which aperture the setting "hangs" depends on the range of Auto-ISO. With ISO 100-3200 or 200-6400 it is f/4, with ISO 100-1600 f/5.6 etc. If you use ISO 100-400 it is f/11 and you will hardly notice the effect. Anyway, it is a bug!
10-08-2009, 02:22 AM   #11
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Okay, you're right, I reproduced your problem... In auto-iso, shutter speed cannot be lowered past a given (and random!!!) aperture, even if there is still ample room to do it...

This is indeed a strange behavior, and must be a left-over of the K20 HyP bug...
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