ISO, LaForet's multiples of 160, 320, 640 etc.

The_Thames · Apr 11, 2014

I'm wondering how important is it to use the ISO settings on the 5D3 that Vincent LaForet suggests? The ISO of 160, 320, 640 etc rather than the settings in-between. Is this for post editing, or in the real world are people going to notice? In video you shutter rate and aperture are pretty much fixed, so the leaves one with only the ISO, and external lighting if possible. Is it a hard and fast rule to stick with LaForet's multiples your should you break this rule to get the best ISO setting for the exposure?

D-B-J · Apr 11, 2014

Personally, I've never heard of LaForet's rues. And those are stop intervals, with nothing in between. Personally, my camera is set to change ISO by a third of a stop, so I can get as many options as possible to allow me to nail the exposure. IE: ISO 100, 125, 140, 160, 200, 250, 280, 320, etc. I'd do this, unless there's a reason you want to only move in stop-intervals.

Jake

KmH · Apr 12, 2014

Vincent Laforet

Yep. Those are full stop steps of ISO adjustment - Stops and Exposure - Beginners Guide to Photography - Photonhead.com

The_Thames · Apr 13, 2014

Perhaps I didn't ask the question right. I was wondering if anyone could tell the difference or how important it was to use multiples of 160 for the cleanest image.

From Vincent La Foret's blog.

"While shooting you will want to shoot at multiples of ISO 160 (only available if Highlight Tone Priority is disabled) or the closest available number (as 1250 is not a multiple of 160, but the closest there is to 1280). I recommend this is because the 5D mk II uses digital noise to step between ISO’s. Technically, the camera is native on the ISO’s that are multiples of 100. For the ISO’s in-between, the camera digitally pushes or pulls one of these native ISO’s. For instance, ISO 125 is really ISO 100 with a digital exposure push, and ISO 160 is really ISO 200 with a digital exposure pull. As a result, 160 and its multiples look the "cleanest" because its really a native ISO rating with the exposure pulled down, which hides more of the digital noise."

Big Mike · Apr 14, 2014

I think I understand what you're asking, but I have no idea if that is actually how the 5DmkII works. I've never heard that before so I'd like to see some good sources for that information.