5D MKiii RAW size after firmware update

I recently updated the 5D Mkiii's firmware from 1.2.1 to 1.2.3, and I noticed that the RAW file size went from ~37MB to ~25MB. Did the firmware update change this or something, because i didn't see that on the changelog for the update. Any ideas? Thanks

mknabster wrote in post #16897237
I recently updated the 5D Mkiii's firmware from 1.2.1 to 1.2.3, and I noticed that the RAW file size went from ~37MB to ~25MB. Did the firmware update change this or something, because i didn't see that on the changelog for the update. Any ideas? Thanks

Are you somehow comparing the same file, both before and after, or different files. If I'm not mistaken, the file size can vary depending upon ISO, brightness, saturation, amount of detail, etc. Still, a 25MB RAW file is pretty small for the 5DIII.

Well, I actually just bought the camera last week, so it's brand new for me. But when i took test pics before and after the update, all the files averaged 37MB before, and now they're averaging 25MBs. So I don't know if that was normal or not ,because i would think there would be more info store in a 22.3 MP image than 25MBs.

Were you shooting the same sort of scene, at the same ISOs?

I generally find my 5D3 files are around 23-28mb, so 25 is not unusual at all. If there are areas of similar tone in the image (blue sky or grey road for instance) or without a lot of fine detail, and shot at low ISO, that would be where I would expect it to be.

I would only expect it to get up much above 30mb if I was shooting scenes with a lot of fine detail (such as leafy foliage) no solid areas of tone and / or shooting at high ISO.

The file size can vary a lot, depending on how much it can be compressed. If you have only had the camera a week, I'm guessing that what you shot before the update is different to what you just shot after the update, and the difference you are seeing is just the difference in compression allowed between the two scenes.

I am still using the original firmware, I have never bothered updating it, so my typical file size of around 25mb is not due to newer firmware.

Ok good to know sandpiper, that makes me feel better. I was going through the settings and changing things like the auto ISO and such, and now that i think about it, the 37MB ones were in a darker room with the higher ISOs like 6400. Then after I messed with the settings, I put the ISO on L (50), and then i started to get the smaller file sizes.

mknabster wrote in post #16897364
Ok good to know sandpiper, that makes me feel better. I was going through the settings and changing things like the auto ISO and such, and now that i think about it, the 37MB ones were in a darker room with the higher ISOs like 6400. Then after I messed with the settings, I put the ISO on L (50), and then i started to get the smaller file sizes.

Yeah, I just checked some I shot at higher ISO at the theatre a little while back, and they were around the 35mb mark. The difference you are seeing is largely down to the noise difference, as noise adds a large amount of "detail" to an image, when it comes to compressing the data.

Huh, that makes more sense. Well, i surely have a lot to learn then, but i'm glad there's nothing wrong. I bought this bad boy as a replacement to my 30D, but i think i'm going to have a lot of fun with it. Thanks for your help!

High ISO = larger files...all normal

rejay14 wrote in post #16898112
High ISO = larger files...all normal

So normal in fact that as you up the ISO then the possible number of images that can be stored on the card, in the top LCD goes down.

Alan

Yes. Higher ISO = large file size, which directly affects the total number of images that can be stored on any given card. My 5D3 images can be 22-40 mb.

Jeff