Is there something like auto EV, or auto M mode, where you set the exposure and then what ever setting you change (F, shutter speed, ISO), there is auto correction with one of other two?
For example, you choose 1/160, f4, and ISO 800 to be the right exposure. Now, when you change to f2.8, ISO automatically changes to 400 or shutter speed changes to 1/320, whatever you choose, or both. You maintain the same exposure level, but are quickly tuned to the different type of action or depth of field requirements.
P doesn't react to changes in aperture or shutter speed.
I am not aware of such a universal half-automation mode. To be honest, by using auto-ISO and A mode, I get what I want. I presume S mode fans feel the same. I am surprised that you want to have both available in one mode. How is it supposed to know which of the two "other" controls you want to change? For example, when moving aperture, should the camera change ISO or shutter speed? If you have to choose this, wouldn't you also want to change your mind and sometimes have to dive into a menu anyway? I don't see that it gains much, if anything, over the simple modes.
carstenw wrote:
.. To be honest, by using auto-ISO and A mode ...
This is what I do.
I just wish all cameras let you choose a min SS for this purpose, sadly many do not. I just got a 6d and Canon finally allows you to set a minimum SS with auto-ISO and this makes a huge difference in its usability.
carstenw wrote:
How is it supposed to know which of the two "other" controls you want to change? For example, when moving aperture, should the camera change ISO or shutter speed?
You set it before.
If you have to choose this, wouldn't you also want to change your mind and sometimes have to dive into a menu anyway?
No.
I don't see that it gains much, if anything, over the simple modes.
Okay, so you want to, for example, set aperture and have the camera always change shutter speed: A. Change aperture and have the camera change ISO: M + auto-ISO. And so on. The only thing missing is to have a mode where you can change A and have it change S, OR change S and have it change A. I don't see the advantage, to be honest, as this implies a dramatic change in shooting style, and probably requires other changes to the settings such as drive mode, ISO mode, etc. And it would complicate the camera with yet another option.
I think some P modes might allow you to change the A/S combination the camera chooses with the thumbwheel, like Bif hinted, in case that helps.
Under what circumstances do you desire this functionality, and what would you want to choose between specifically?
carstenw wrote:
Under what circumstances do you desire this functionality, and what would you want to choose between specifically?
It is quite simple.You don't want the camera to mess with your set exposure level, or in other words, you want the camera maintain your set exposure level no matter what you do.
For example. You are in manual mode and suddenly you want deeper dof. You close the aperture but don't want the SS to change. Here should auto ISO compensate for the aperture difference.
This would work only with lenses that have the aperture set by the camera or if you turn the aperture ring on the lens and camera recognize it.
carstenw wrote:
P doesn't react to changes in aperture or shutter speed.
What? I guess my camera is busted then cuz that's what mine does. I turn the dial and the SS compensates to match the aperture or you can look at it like the aperture compensates to match the SS - either. Switch on or off Auto ISO with that and you pretty much have what the OP is describing.
Any one of the three exposure triangle elements can be modified and the others will compensate.
Bifurcator wrote:
I guess I'm not understanding... Oh well...
I want to lock exposure and still be able to alter the relation between aperture, shutter speed and ISO. In this case the camera would not use metering at all. Just keep the same exposure so that if I change aperture, shutter speed (or ISO) will automatically change as well.
I'd love this capability. I find a lot of outdoor scenes difficult to meter when the camera is in A mode with matrix metering. I usually end up shooting manual and chimping to get what I'm looking for. But I agree it would be nice to then have an auto-shift with a fixed set EV so I didn't have to compensate all adjustments in manual when I find the exposure I like.
On the A900 it was pretty easy to do that. (maybe except iso), use the AE-lock in toggle mode and then it would lock the exposure to whatever you meter. Then shifting either of the wheels gives an equivalent exposure. The feature is called program shift in sony land. If I remember correctly this even worked in manual mode, the exposure lock locked the exposure and then you shifted the other settings.
With my canon 1d mrk 4 in P mode I can change aperture and shutter speed is compensated to keep the EV and vice verse, this is for a set ISO value. If I set ISO to Auto then ISO is changed when I change the aperture and shutter speed remains constant or aperture is changed when I change the ISO.
I guess that is as close as you can get with only two dials.
I guess my camera is busted then cuz that's what mine does. I turn the dial and the SS compensates to match the aperture or you can look at it like the aperture compensates to match the SS - either. Switch on or off Auto ISO with that and you pretty much have what the OP is describing. 