Raw Vs sRaw Vs jpeg (Large/fine)

[scotteffone]

I realise shooting in full RAW is the bestest but I'm interested in the other two options:

Following details from Canon 40D manual:

RAW = Approx. 12.4 MB (3888 x 2592)
sRAW = Approx. 7.1 MB (1936x 1288)
jpeg (large/fine) = Approx. 3.5 MB (3888 x 2592)

What I want to know is if you had to abandon RAW because you were running out of room would you choose either jpeg (large/fine) or sRAW? As far as I know RAW is every bit of data possible with no compression. What is sRAW? Does it retain the same editing qualities but just in a smaller ratio? And how bad is it to edit a jpeg? Does it really matter when you are only doing a few lighting tweaks?

Please bear in mind I'm not a fancy pants when it comes to super critiquing photos and looking for the tiniest evidence of compression. I'm just interested in hearing the pros and cons between sRAW and jpeg (large/fine).

Thank you.

[ricktas]

Must be a Canon thing, but sRAW appears to have no where near as many pixels so is some form of cropping, reducing the pixel size of the photo. Whereas from the information you provide shows that RAW and jpeg both have the same pixel dimensions, so if I needed to swap to JPG, I would just choose that.

The best way is to buy another memory card so you don't need to change formats and can use your preffered one all the time.

[fillum]

It looks like sRAW is aimed at shooting for the web (or small prints) where you you don't need a lot of resolution but still want the extra control in post prod that comes with raw. sRAW might be useful in difficult lighting conditions (eg combination of bright sun with deep shadows), but I'd usually shoot full RAW and switch to jpeg fine (due to higher resolution than sRAW) if I needed smaller file sizes.

BTW, raw files can be compressed. It depends on the type of compression ("lossless" vs "lossy") as to whether data is lost.



Cheers.

[scotteffone]

It looks like sRAW is aimed at shooting for the web (or small prints) where you you don't need a lot of resolution but still want the extra control in post prod that comes with raw. sRAW might be useful in difficult lighting conditions (eg combination of bright sun with deep shadows), but I'd usually shoot full RAW and switch to jpeg fine (due to higher resolution than sRAW) if I needed smaller file sizes.

BTW, raw files can be compressed. It depends on the type of compression ("lossless" vs "lossy") as to whether data is lost.



Cheers.

Thanks,

So basic edits on a jpeg over an sRAW - or even a full RAW for that matter - is not really that much of an issue quality wise (and you retain the higher resolution which is a benefit)? Ideally I want to buy extra cards but just interested.

[yummymummy]

My 50D has the same thing, from what I can see, RAW, and sRAW are just the same, just one is smaller than the other, meaning you can fit more on the card.

[agb]

The canon 7D has 9 image size choices. Raw, 25.1MB,Mraw 17.1, sRaw 14.4, and 6 jpeg sizes from 6.6MB to 1.1.
This article tell a bit about sRaw,in technical terms. http://dougkerr.net/Pumpkin/articles/sRaw.pdf
This is canon's exlanation of why it exists http://www.usa.canon.com/dlc/controller?act=GetArticleAct&articleID=2106
I think that mRaw and sRaw are not the same as Raw. They have to have been demosaiced and resampled somehow to reduce the file size.

[soulman]

Yep, sRAW is just RAW but smaller. Possibly useful for some things, but worth noting that it was not widely supported by image editing programs when I last checked. You're probably better off with JPEG if you're not too worried about the lossy compression. JPEGS are very good considering how much space they save you and you have to save them repeatedly at low quality settings to get obvious artifacts. The only major practical disadvantage of JPEGs from my point of view is the lack of colours - only 8 bit as opposed to 14 bit for the 40D's RAW files. This makes a big difference if you're trying to produce delicately toned prints.

This thread (http://www.ausphotography.net.au/forum/showthread.php?47708-JPEG-or-RAW) also has a very long and comprehensive discussion about the differences between RAW & JPEG.

[soulman]

This article tell a bit about sRaw,in technical terms. http://dougkerr.net/Pumpkin/articles/sRaw.pdf
I think that mRaw and sRaw are not the same as Raw. They have to have been demosaiced and resampled somehow to reduce the file size.Interesting. So sRAW is not quite a small RAW after all, though obviously very similar in practice.

[ameerat42]

And so says THIS BLOKE (http://www.chrisridley.co.uk/blogs/all-posts/sraw-files/)
(Now that I know, I'll avoid it.)
Am.

[scotteffone]

This article tell a bit about sRaw,in technical terms. http://dougkerr.net/Pumpkin/articles/sRaw.pdf
This is canon's exlanation of why it exists http://www.usa.canon.com/dlc/controller?act=GetArticleAct&articleID=2106
I think that mRaw and sRaw are not the same as Raw. They have to have been demosaiced and resampled somehow to reduce the file size.

Great links.


You're probably better off with JPEG if you're not too worried about the lossy compression. JPEGS are very good considering how much space they save you and you have to save them repeatedly at low quality settings to get obvious artifacts. The only major practical disadvantage of JPEGs from my point of view is the lack of colours - only 8 bit as opposed to 14 bit for the 40D's RAW files. This makes a big difference if you're trying to produce delicately toned prints.

I think I'm leaning towards the high jpeg setting if I had too choose. Mainly because if I wanted to make a larger print the sRAW would be too small.

EOS 5D Mark II EOS 50D

RAW: 30"x40", or larger 20"x30", or larger
sRAW 1: 13"x19" 11"x14"
sRAW 2: 11"x14" 8.5"x11"

I think I will do some tests to see.

I will research more into jpeg to see how hard you have to hit the file before it looks terrible in prints.

Thanks for your replies.

[Chris Ridley]

That bloke will be me! I found this website through my Google stats today so thought I would stop by and see what was going on.. so hello all :)


And so says THIS BLOKE (http://www.chrisridley.co.uk/blogs/all-posts/sraw-files/)
(Now that I know, I'll avoid it.)
Am.

[scotteffone]

That bloke will be me! I found this website through my Google stats today so thought I would stop by and see what was going on.. so hello all :)

Haha awesome! Welcome! So RAW or JPEG? Haha!

[agb]

That bloke will be me! I found this website through my Google stats today so thought I would stop by and see what was going on.. so hello all :)
Thanks for dropping in.

[Finlaw]

I found this very interesting after reading all the info if i couldn't shoot Raw, I'd shoot jpg. I would still save my jpg to a lossless file format for editing before saving back as a jpg though.