K100D on Auto ISO - SR kick in first or ISO ramped up first?

[caterham7]

as above...suddenly thought of this scenario

with ISO on Auto (e.g. 200-1600) and SR on [plus on Program mode], if the camera detects low light, will it initiate SR, or ramp up ISO, or both?...

[Zenten]

Originally Posted by caterham7 as above...suddenly thought of this scenario with ISO on Auto (e.g. 200-1600) and SR on [plus on Program mode], if the camera detects low light, will it initiate SR, or ramp up ISO, or both?...

Bro, I think you are utterly confused and also confusing others.

SR once switched on remains on irregardless of the ISO

[caterham7]

oops...

[fengwei]

Originally Posted by caterham7 oops...

Well, I still think what you asked is quite interesting. For us Ds/DL users, the camera will up ISO according to 1/focallength rule. But w/ the K100d, would the camera do the same?

Let's say, for a DS, when using a 50mm lens, when light condition is dim, the camera will up ISO to a higher value to keep the 1/50s rule. But K100d has SR feature which is like 2-4 stops extra light. So the camera would only need to keep 1/25s or even 1/15s rule (thus a lower ISO value compared w/ a DS) ?

Maybe we should put a DS and a K100D together for the same scene at the same time, w/ same auto ISO setting, and see what's gonna happen

[dnaxe]

I'm quite sure that ISO goes up first, but don't quote me on it.

However, SR is always on - it's just that it might not need to perform to extremes (e.g. shutter might not drop to 1/8, 1/6 )

[alvinsclee]

Just tested my K100D for this... it does not seems to matter if SR is on or off.

Under limited light conditions, ISO goes up first. The camera then tries to fully open the aperture and adjust the shutter speed to ensure enough exposure. Only when there is enough exposure, then the rest kicks in... such as ensuring the 1/focal length rule, thereafter it will try to balance BOTH the shuttle speed and aperture.

However, if you use manual lens, it is very important to enter the correct focal length of the lens used... otherwise, SR is worse than without SR! Therefore, SR is easier used on manual prime lens than zoom lens (one reason why I am starting to be inclined towards the primes )