RAW vs JPG explain it to me one more time

[NicoleScraps]

So I understand what everyone has said about raw being better. I mean, I understand all of the reasoning behind WHY it is supposed to be better and probably IS better in difficult lighting.
But I tried it out for the first time today. I set my camera to RAW+ jpg. Honest to goodness, I don't really see a whole lot of difference between the two.
What am I missing? Here are both images. I did absolutely no editing except for a crop and reduction to put them online.

Here's the jpg



Here's the raw



Maybe someone with a better eye for the technical details can pick out the differences but I see very little. I think the RAW image is a little bit lighter and slightly less saturated, but other than that, I see nothing different.

On another note, aside from the obvious that I need to fix where he scratched his face, how would you edit this photo? What steps would you take in either raw or jpg? Just curious what different answers I might get to that question. I have PSE 8 and LR 3.

[IABoomer]

I think where RAW really shines is when you want to make big edits to the image. If you post-process a lot and create a certain style for your images, you may not be able to get that look directly in camera, so giving yourself as much latitude as possible for editing is important.

If you haven't seen them, check out the two part Jared Polen videos and images from his RAW vs. JPEG week.

Photography, Digital Camera & Lightroom Tips — FroKnowsPhoto RAW vs JPEG Side by Side Comparison

[BuddhaPi]

The Fro Knows!

[autofocus]

Originally Posted by NicoleScraps

So I understand what everyone has said about raw being better. I mean, I understand all of the reasoning behind WHY it is supposed to be better and probably IS better in difficult lighting.
But I tried it out for the first time today. I set my camera to RAW+ jpg. Honest to goodness, I don't really see a whole lot of difference between the two.
What am I missing? Here are both images. I did absolutely no editing except for a crop and reduction to put them online.

Here's the jpg



Here's the raw



Maybe someone with a better eye for the technical details can pick out the differences but I see very little. I think the RAW image is a little bit lighter and slightly less saturated, but other than that, I see nothing different.

On another note, aside from the obvious that I need to fix where he scratched his face, how would you edit this photo? What steps would you take in either raw or jpg? Just curious what different answers I might get to that question. I have PSE 8 and LR 3.

RAW is nothing but data, or as many refer to it as the digital negative. It is lossless and not compressed, and basically it identifies each pixel and what it's supposed to look like. A RAW file is then compressed in your camera to a JPEG just so you can see it on your little LCD screen. Being that JPEGs are compressed files the camera is making the decision as to what pixels are kept, and which ones are discarded, and ultimately, that is the JPEG you'd wind up with if you were shooting in JPEG mode. It's not uncommon for more than 2/3's of the data to be discarded in this process. That's why shooting RAW with all the data gives you a better chance to recover and broaden the dynamic range of the image. In your example above you have to remember that you cannot see a RAW image as an image (it's data) and when you open that image in your RAW software, and then over to Photoshop you are really seeing the image converted to another industry standard (such as JPEG, TIFF, etc)
I'm sure most would agree that it's better for you to make those decisions rather than allow the camera to do it for you...it's all about latitude Vs ease

[nickbedford]

Originally Posted by autofocus

RAW is nothing but data, or as many refer to it as the digital negative. It is lossless and not compressed, and basically it identifies each pixel and what it's supposed to look like. A RAW file is then compressed in your camera to a JPEG just so you can see it on your little LCD screen. Being that JPEGs are compressed files the camera is making the decision as to what pixels are kept, and which ones are discarded, and ultimately, that is the JPEG you'd wind up with if you were shooting in JPEG mode. It's not uncommon for more than 2/3's of the data to be discarded in this process. That's why shooting RAW with all the data gives you a better chance to recover and broaden the dynamic range of the image. In your example above you have to remember that you cannot see a RAW image as an image (it's data) and when you open that image in your RAW software, and then over to Photoshop you are really seeing the image converted to another industry standard (such as JPEG, TIFF, etc)
I'm sure most would agree that it's better for you to make those decisions rather than allow the camera to do it for you...it's all about latitude Vs ease

JPEG doesn't "throw away pixels", it throws away colour accuracy.

Both the RAW file and the JPEG have the same pixel count (if not in the same format, i.e. bayer pattern vs simple RGB grid).

[autofocus]

Originally Posted by nickbedford

JPEG doesn't "throw away pixels", it throws away colour accuracy.

Both the RAW file and the JPEG have the same pixel count (if not in the same format, i.e. bayer pattern vs simple RGB grid).

If JPEG is a compressed file, how can it be the same pixel count as RAW..and why is a RAW file that's ~25MB Vs the same file converted to JPEG now much smaller? Where did they go after the compression algorithm got done with them?..or are those pixels just turned off in the process? And I'm not sure if RAW even has a pixel count, it being only data...is it not just a set of instructions that's used to create the image?

[digirebelva]

Originally Posted by nickbedford

JPEG doesn't "throw away pixels", it throws away colour accuracy.

Ummm, everything I have ever read on jpeg states that it in fact DOES throw away pixels when its compressing...

From everybody favorite source Wikipedia
"The compression method is usually lossy, meaning that some original image information is lost and cannot be restored (possibly affecting image quality.) "

"JPEG is also different in that it is primarily a lossy method of compression. Most popular image format compression schemes, such as RLE, LZW, or the CCITT standards, are lossless compression methods. That is, they do not discard any data during the encoding process. An image compressed using a lossless method is guaranteed to be identical to the original image when uncompressed.

Lossy schemes, on the other hand, throw useless data away during encoding. This is, in fact, how lossy schemes manage to obtain superior compression ratios over most lossless schemes. JPEG was designed specifically to discard information that the human eye cannot easily see".

[jml79]

Take the same picture and under expose it by 2/3 or 1 stop with an incorrect colour balance then try to fix each. Let me know which one does better.

Raw gives you extra latitude when you or the camera makes a mistake. It can also allow some effects that are difficult if not impossible with jpg.

@nickbedford - JPEG doesn't "throw away pixels", it throws away colour accuracy.

Oh the semantics. Technically you are correct. jpg images have the same number of pixels but jpg does throw away the individual values of many pixels.

@autofocus - And I'm not sure if RAW even has a pixel count, it being only data...is it not just a set of instructions that's used to create the image?

Raw does have a pixel count. It is an image on its own and can be viewed in its native format (it looks very green). Each pixel in a raw file is a number (usually 12-14 bits) that corresponds to the amount of light coming through the light filter on each pixel lens. What is interesting is that each pixel in your camera is only one colour. Red, Green or Blue (RGB). There are 2 green pixels for each red or blue. The camera or your Raw software takes the information from each pixel and its neighbouring pixels and estimates the real RGB value of the pixel.

An uncompressed TIFF file usually has a 24bit number for each pixel which is why it is so large. The most amazing thing is a jpg represents more information than a raw file.

For more information - http://www.cambridgeincolour.com/tutorials.htm

[autofocus]

Originally Posted by digirebelva

Ummm, everything I have ever read on jpeg states that it in fact DOES throw away pixels when its compressing...

From everybody favorite source Wikipedia
"The compression method is usually lossy, meaning that some original image information is lost and cannot be restored (possibly affecting image quality.) "

"JPEG is also different in that it is primarily a lossy method of compression. Most popular image format compression schemes, such as RLE, LZW, or the CCITT standards, are lossless compression methods. That is, they do not discard any data during the encoding process. An image compressed using a lossless method is guaranteed to be identical to the original image when uncompressed.

Lossy schemes, on the other hand, throw useless data away during encoding. This is, in fact, how lossy schemes manage to obtain superior compression ratios over most lossless schemes. JPEG was designed specifically to discard information that the human eye cannot easily see".

+1 Looks like we're in the same camp on this

[jml79]

Neither of the articles that have been quoted explain exactly what data is discarded, just that some data is thrown away. When JPG compresses a file the data that gets thrown away is colour data. The pixels are still there. Take any raw, convert it to jpg and check the file details. It still has all of it's pixels. They are all there. Just some of the colour data is gone. The part that the human brain won't notice.