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Message: <blockquote data-quote="tdodd" data-source="post: 1693804" data-attributes="member: 55450">In simple terms, yes, but don't let the ISO be the driving force of your decision making. The creative controls are shutter speed, to control motion, and aperture, to control DOF. You then use a suitable ISO as necessary to get the brightest exposure you can, without clipping important highlight details.As an example, suppose you are shooting a dark or mid-toned bird in amongst some green foliage. There are no (important) bright tones anywhere in the scene. Maybe there is some sky in the background but it does not interest you and you will crop it out later. You can ignore the sky. It is irrelevant.Now, a "correct" exposure for your brown bird in green foliage is very much centred around the mid tones, or perhaps a little below middle. If the scene was lit by sunlight you might pick an exposure of 1/800, f/8, 200 ISO. (that is equal to a "Sunny 16" exposure) But there are no bright tones so your histogram peaks a little below centre and there is nothing at all in the brightest 2 stops. That is an awful lot of unused data that you could make use of. You don't want to reduce your shutter speed because you want to protect yourself from shake/blur. You don't want to open up your aperture because you need some extra DOF. However, there is no reason you cannot increase your ISO to 400 or even 800, in this scenario.The resulting image will look way too bright, initially, but in your raw processor - Lightroom, DPP, whatever, you will reduce the exposure by 2 stops (or whatever looks good). In so doing you will reduce noise and you will have more image data to play with. The article I sent you about ETTR explains that.Of course, you are not compelled to raise the ISO, but it is an approach that should help. As I also said in the PM, it would be worse for IQ to underexpose and then brighten later on, because in so doing you will have limited the amount of data you have to work with and will make any noise become more visible.Here are four example of shots that were all pretty bang on, just nudging a hint of clipping, easily recoverable if required. In the fifth one it looks like I could/should have bumped ISO to 1600.</blockquote>

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