M mode with AE-L with K5/K1/KP

[KPM2]

Hello

When I use the M mode and use AE-L, I expect that I can shift the aperture/shutter speed combination in a way that I always get the same exposure. That works with my K5, K1 and KP.

But what do the cameras, when I change the ISO during that AE-L lock ?

The K5 and the K1 do now not shift, I do therefore underexpose or overexpose now my exposure by changing the ISO !

The KP do still shift. It change by a ISO change the shutter speed on my KP, so that my exposure is still the same.

It would be nice if the K1 would do the same as the KP here !

best regards KPM2

 

[ozdean]

Why do you want to change it after you've locked it?

Wouldn't it be better to get it how you want it before locking?

 

[soheil]

Actually I believe the way K5/K1 does it is the way to go in M mode. I prefer I'd the one at the helm in manual mode not the camera.

 

[KPM2]

Hello ozdean

In the program modes I use AE-L when I meter on a part of the scene, which I would not meter on for the framing I use for the picture (for example in the spot metering).

The M mode I use a lot for flash pictures. Here, I meter for example to a ambience light source. Now I use AE-L for an other reason, because when I use different apertures for the pictures, the camera do change automatically the shutter speed now, so that my exposure for this light source is still the same. But sometimes I can not get the aperture I will have, because the shutter speed would get too slow. All what I must do now is changing the ISO, so that the shutter speed can get faster again. But this I can not do with a K5 or K1, because both cameras do change only the ISO but not also one other variable ( = the aperture or shutter speed) so that my AE-L lock is worthless now and I get an other exposure for my ambience light source. Only my KP change also an other variable (which one the KP use, depends on the setting for the green button in the M mode: TV shift and P LINE let the KP change the shutter speed, Av shift let the KP change the aperture... when I change the ISO, so that my AE-L lock end up in having still the same exposure for this ambience light source.

Why do you want to change it after you've locked it?

Wouldn't it be better to get it how you want it before locking?

--
Regards Dean - Capturing Creation
N.B. All my Images are Protected by Copyright

best regards KPM2

 

[James O'Neill]

Hello

When I use the M mode and use AE-L, I expect that I can shift the aperture/shutter speed combination in a way that I always get the same exposure. That works with my K5, K1 and KP.

But what do the cameras, when I change the ISO during that AE-L lock ?

The K5 and the K1 do now not shift, I do therefore underexpose or overexpose now my exposure by changing the ISO !

The KP do still shift. It change by a ISO change the shutter speed on my KP, so that my exposure is still the same.

It would be nice if the K1 would do the same as the KP here !

best regards KPM2

This doesn't make sense to me. You don't have auto-exposure in M mode. You set the ISO , Shutter and Aperture and the meter tells you how far you are from what it thinks is the right exposure. So if you use AE-Lock it should tell you how far the settings are from the reading it took, whether you change ISO , Shutter or aperture, that's exactly what my K1 did when I tested it a moment ago. If you change ISO in manual mode, it doesn't change shutter or aperture, it tells you how far the exposure is from what the meter suggests, and leaves you to adjust.

The KP behaviour as described sounds wrong - it would certainly be possible to emulate it with a firmware change, but I suspect more people would say "manual means leave the settings I set, as I set them".

 

[KPM2]

Hello soheil

Actually I believe the way K5/K1 does it is the way to go in M mode. I prefer I'd the one at the helm in manual mode not the camera.

 

[KPM2]

Hello James O'Neill

Hello

When I use the M mode and use AE-L, I expect that I can shift the aperture/shutter speed combination in a way that I always get the same exposure. That works with my K5, K1 and KP.

But what do the cameras, when I change the ISO during that AE-L lock ?

The K5 and the K1 do now not shift, I do therefore underexpose or overexpose now my exposure by changing the ISO !

The KP do still shift. It change by a ISO change the shutter speed on my KP, so that my exposure is still the same.

It would be nice if the K1 would do the same as the KP here !

best regards KPM2

This doesn't make sense to me. You don't have auto-exposure in M mode. You set the ISO , Shutter and Aperture and the meter tells you how far you are from what it thinks is the right exposure. So if you use AE-Lock it should tell you how far the settings are from the reading it took, whether you change ISO , Shutter or aperture, that's exactly what my K1 did when I tested it a moment ago. If you change ISO in manual mode, it doesn't change shutter or aperture, it tells you how far the exposure is from what the meter suggests, and leaves you to adjust.

The KP behaviour as described sounds wrong - it would certainly be possible to emulate it with a firmware change, but I suspect more people would say "manual means leave the settings I set, as I set them".

I use no auto exposure in the M mode, that's clear. But AE-L do simple an other thing.

Let's say I have found my exposure for a picture and I use a small DOF via a f 2.8...ok...for the next picture I will use a bigger DOF but I can use the same exposure for it. Here, I can simple use the AE-L for that, because now the camera shift the aperture/shutter speed, so that I can use now a higher aperture for my bigger DOF, mean while the camera use a lower shutter speed for to keep the same exposure. I think that this is a realy simple use of it. It's only that the K5 and K1 is not consequence, because it do not shift when I change the ISO, meanwhile the KP do that now.

best regards KPM2

 

[ozdean]

Interesting how you are using it on your kp?

 

[KPM2]

Hello ozdean

Interesting how you are using it on your kp?

--
Regards Dean - Capturing Creation
N.B. All my Images are Protected by Copyright

I still have had my breakfast test scene there, so here the examples.

I use for my KP a User mode 5, where it's set to manual, C1 on the function wheel to ISO, the green button for the M mode to P LINE.

I meter.... but be carfull when you use for that the green button, because when the P-TTL flash is on, the green button do not set your bar graph position as usual to 0 EV !

and than I use AE-L and take pictures and can change the aperture/shutter speed with the front or back wheel, the shutter speed/ISO with the third wheel and I use always the same exposure for the ambience light. Only the needed flash power is different, because the flash exposure works together with the ISO and aperture, but not with the shutter speed, but in P-TTL, the camera regulate the needed flash power for that really good.







EDIT: when you would use your flash not in P-TTL, you use it instead in manual mode, this use of AE-L like I do it here is than restricted. Because: when you change the aperture/shutter speed combination, the exposure of the ambience light is still the same, but the additional exposure of the flash do change ! The constant flash light add stronger to the exposure with a lens at f2.8 as with f11 for example. So, for to let the constant flash light add always the same to the exposure, you can only change a aperture/ISO combination. For to do that, you must set the green button in the M mode to Av shift. Than, when you use the third wheel, the KP change a Aperture/ISO combination, but again, do not change a shutter speed/aperture combination. You can of cause do that, when you will variate with it the additional flash exposure to more or less.

best regards KPM2

 

[Fogel70]

Hello

When I use the M mode and use AE-L, I expect that I can shift the aperture/shutter speed combination in a way that I always get the same exposure. That works with my K5, K1 and KP.

But what do the cameras, when I change the ISO during that AE-L lock ?

The K5 and the K1 do now not shift, I do therefore underexpose or overexpose now my exposure by changing the ISO !

The KP do still shift. It change by a ISO change the shutter speed on my KP, so that my exposure is still the same.

It would be nice if the K1 would do the same as the KP here !

best regards KPM2

Pentax Hyper-Manual mode was designed in the early 90s for film SLR, so AE-lock has not been using ISO as an input. It seems like KP is one of the first to do so.

It has been other limitation like this on previous cameras. FI using green button in Hyper-Program mode did not use ISO for setting exposure if using auto ISO.