Crop Factor, Low Light and Aperture with m4/3 lenses?

Started Jun 15, 2014 | Discussions thread
Ontario Gone
Ontario Gone Veteran Member • Posts: 4,183
Re: Very simple:
1

Just another Canon shooter wrote:

The best way to think about this is in equivalence terms. FF does not have a lower noise advantage (for equivalent images) - it has the same noise (but better resolution in general, which can offset some of that). You can trade in DOF for less noise with any system. What FF does better is that it has more latitude, with the common lenses, to get a shallower DOF, which means more total light and therefore less noise.

Hmm, i don't think this is right. Yes it's true that current FF have more pixels, but it doesn't have to be that way, it's just happenstance atm. If resolution was the same for a MFT vs FF, and if you shoot at equivalent settings, its all the same. Why? Diffraction. Diffraction causes diminishing returns with higher resolution, but it's based on aperture. With equivalence settings, aperture is equal, which means both are affected equally by diffraction, both have equal IQ numbers like ISO/DR/color, and both have the same pixel count.

Many will assume MFT is more affected by diffraction if we compare a MFT @F2 vs FF @F4. This is not true, since the entrance pupils are going to be even.

Since the OP mentioned APS-C - the m43 has the advantage of having more lenses designed for it, and IBIS. If I know that I will never go FF (well, I already did ), I would rather get an m43 system because of the better suited lens selection, IBIS, weight and size. The recent mirror-less Fuji, etc. are other interesting options.

EDIT: About the post above: "assume the same ISO..." - don't. There is no reason to assume that. Think about auto ISO, or even better, no ISO at all. You chose the aperture and the shutter speed; the ISO is a secondary thing.

You have to think about ISO, even if it's just base ISO. After all, it's not the number that matters, its the boosting. Whatever that amount is, it matters. If the manufacturer numbers bother you, make a chart, call it by "real" ISO numbers. Either way, it's a factor the needs to be equalized in terms of equivalence.

-- hide signature --

"Run to the light, Carol Anne. Run as fast as you can!"

 Ontario Gone's gear list:Ontario Gone's gear list
Nikon D7000 Canon EOS 70D Nikon AF-S DX Nikkor 35mm F1.8G Nikon AF-S Nikkor 50mm f/1.8G Canon EF 40mm f/2.8 STM
Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow