RAW: Why Do I Care?

[mcaldwell]

I have Google'd the subject to death and got nowhere. My son has a degree in computer arts, can make PS stand up and spit nickels, but I am a photo rookie and an engineer to boot, so "art challenged" and specification / data oriented. I have mentioned to my son that the DRebel XT I plan to buy soon offers both JPEG and CR2 file formats. He is more into computer generated stuff, not digital photography, so has challenged just what improvement, capabilities, etc, I gain with CR2 vs JPEG. Well, I don't really know!

Disregarding file size, cost of storage, etc, strictly from the standpoint of being able to produce a higher quality image (or not), what is the big deal of RAW over high quality JPEG setting? I am particularly interested in the "why." Thanks for the tutorial!

Mike

[robertwgross]

Mike, I'm sure you will get various opinions on this. Here is mine.

CR2 is the file extension for a RAW file. That means the image file is "straight from the sensor" with virtually no processing, modification, or compression. If you are any sort of a purist, this will be of interest to you. However, once you transfer the files from the CF card into the computer, you need to convert the RAW file to make it usable to normal desktop applications, so you may want to end up with a TIF or a JPEG. Most RAW converters allow you to view and tweak the file before actual conversion. By "tweak," I mean modify the apparent exposure, contrast, and color balance. Additionally, RAW files from most of our cameras are 12-bits. TIF is a good format for editing purposes, since it is non-compressed and does not continue to degrade with continual savings (like JPEG does). TIF 16-bit is good if you have huge amounts of disk and memory, and if you intend to make big changes. TIF 8-bit is good enough for mere mortals. However, at the end of the day, if you are publishing to the web or trying to attach to some email, you'll convert to JPEG format. I hate to convert to JPEG until absolutely 100% of any editing changes are done. JPEG is 8-bits, and once you are there, you would not want to go "back up" to 16-bits (since the damage is already done). One advantage of converting to JPEG in the computer (not in the camera) is that you can control the degree of JPEG compression. You can compress it hard if it is a less important file, or you can compress it gently if it is a very important file. In the cameras that most of us have, JPEG options are few. Also, as I mentioned, continual JPEG saving causes tiny image detail to slowy disappear. If you never print anything large, then the small differences won't show. However, if you do print large, the small differences can be seen, and maybe you simply don't like to compromise.

If space were terribly expensive, then I would understand the need to make some compromises. However, memory and disk space is cheap.

---Bob Gross---

[tim]

Short answer: it gives you a massive amount of flexability with the downside of additional processing time.

A bit more: This is especially useful if you don't get your exposured perfect (which can be difficult with digital), don't use custom white ballance all the time, or want to tweak shadows and things like that.

I only use RAW.

[kfong]

what is the big deal of RAW over high quality JPEG setting? I am particularly interested in the "why." Thanks for the tutorial!

Mike

Engineer to engineer,
RAW is 36 bit with lossless compression. It is also unprocessed.
JPEG is 24 bit with lossy compression. In particular it uses 8x8 cosine DFT and a user adjustable threshold to throw away the high frequency components. In addition, jpeg from the camera is pre-processed with white balance and unsharp mask.

Ken

[mcaldwell]

Bob, it sounds as though there are RAW converters that allow fiddling while still RAW, or at least the bridge from RAW to TIFF. Are there any that allow you to see the results beforehand, sort of "PS For RAW", or will I have to convert, examine, change something, convert, examine - round and round until I like what I see?

Ken: thanks, that explains a lot.

[tim]

Bob, it sounds as though there are RAW converters that allow fiddling while still RAW, or at least the bridge from RAW to TIFF. Are there any that allow you to see the results beforehand, sort of "PS For RAW", or will I have to convert, examine, change something, convert, examine - round and round until I like what I see?

Ken: thanks, that explains a lot.

In Photoshop CS/CS2 you have a real time preview whenever you change one of the parameters (exposure, contrast, noise reduction, etc).

[lostdoggy]

C1 Phase one gives the same function with better WB function.

Bob you said it all. RAW rulez

[Curtis N]

The sort of person who shells out the extra bucks for a DSLR tends to be the sort of person who takes pride in his photographs and wants everything he prints to be a "winner."

Even the best cameras don't always get the exposure right (and probably never will, for a number of reasons). RAW lets me tweak each image so that it's just where I want it. The ability to set the white balance with the computer means one less thing I have to worry about when I'm shooting.

Add to this the ability to crop and make slight changes in camera orientation to level the horizon (which you can also do with JPEG). Digital photography can make a marginal photographer like me look pretty good. People are usually impressed when I show them my prints, but they would look pretty average if they were straight out of the camera.

The bottom line for me - Every time I get lazy and shoot in JPEG mode, I later regret it.

[ProAc_Fan]

As others have stated RAW rules. I normally leave the jpeg images for things like Ebay auction shots or pics of family members I know I'd never print. Anything intended to go to print is shot in RAW and processed in PS CS before compression.

Mike

[robertwgross]

Bob, it sounds as though there are RAW converters that allow fiddling while still RAW, or at least the bridge from RAW to TIFF. Are there any that allow you to see the results beforehand, sort of "PS For RAW", or will I have to convert, examine, change something, convert, examine - round and round until I like what I see?

To a certain extent, yes, that is what they do.

I will not claim that you can see every nuance. For example, I can't see anything happening with sharpening until it is done.

However, if you don't like the result, you can always go back to the RAW file and do it again with some variation of the same tweaks.

---Bob Gross---

[grego]

Another thing that's nice about Raw is you can get a higher shutter speed by forcing an underexposed shot by like a stop and you can still clean it up in Photoshop CS's raw converter. It's very nice feature.

RAW are big files, and processing takes longer, but the versatility and quality Raw gives you is priceless.

[tim]

If you underexpose an image, even with RAW, you'll get more noise than if you'd exposed it correctly. Remember all the camera does is count photons, filtered through red, green, and blue filters, and counts the photons. The less photons sampled, the higher the error between the pixels, and hence noise. At least that's how I understand it, no doubt someone will correct me if i'm wrong.

[Pelao]

It's a good and important question.

I prefer RAW. Some would argue that if you are new to DSLR it may be better sticking to JPEG while you master your camera before adding the extra post-processing burden of RAW.

I would go RAW from the start as it's not as complex as it appears, and it creates, in effect, a negative similar to film negatives. This means that as your skills improve you can go back and re-process the image. With JPEG you have fewer options and every time you work the file some of it is lost.

A useful read:


RAW or JPEG (http://luminous-landscape.com/tutorials/understanding-series/u-raw-files.shtml)

[PhotosGuy]

Why I love RAW - '53 Ford Sunliner (Fixed)
http://photography-on-the.net/forum/showthread.php?t=43761&highlight=sunliner

http://www.outbackphoto.com/artofraw/raw_18/essay.html

[robertwgross]

RAW is 36 bit with lossless compression.

Ken, I think you will find that RAW is a 12-bit format.

---Bob Gross---

[ed2day]

Ken, I think you will find that RAW is a 12-bit format.

---Bob Gross---

I think he meant 12 bits/color. 12x3=36.

[ed2day]

From a practical viewpoint, for me, the best thing about shooting in RAW is the ability to change white balance after the shot is taken. Shooting in JPEG locks in the white balance you have selected in the camera. You can alter the balance manually afterwards by shifting a bunch of color knobs--but that requires skills I don't have for anything more than a subtle shift. RAW allows you to change the white balance during post processing by selecting from a number of preset options: auto, sunny, cloudy, incandescent or flourescent lighting, etc. White balance is tougher for me to get right in the shot than exposure.

[Curtis N]

Here's an example of why I shoot RAW. It's from a theatre rehearsal. I love the shot, but I was shooting in JPEG mode and forgot to set the white balance to tungsten. Those girls' faces aren't really that yellow. This will be hard for me to fix. Those of you who are good with photoshop could probably improve it with some trial-and-error, but I have another 100 shots that are just as bad!

[symes]

I stayed away from RAW at the start because I was scared of the work and fiddling afterwards. I look at my shots from before and if I had shot them in RAW I could have some real winners...yes with hours of learning photoshop I am slowly able to fix some things but in all honesty it is just a slider with a RAW converter and it is much easier

I like to use Raw Shooter Essentials and it is free on the net...though I am not sure if can handle the XT yet..

Cheers,

[tim]

Here's an example of why I shoot RAW. It's from a theatre rehearsal. I love the shot, but I was shooting in JPEG mode and forgot to set the white balance to tungsten. Those girls' faces aren't really that yellow. This will be hard for me to fix. Those of you who are good with photoshop could probably improve it with some trial-and-error, but I have another 100 shots that are just as bad!

Aye, with RAW you'd select all the images, double click, select all, choose tungsten, hit ok, and that's it. With JPG you probably have to play with a bunch of color sliders.

[poolstok]

Raw does allow for quick colour correction, butif you know your PS and understand colour, you can correct afterwards (although it takes more time)

If you are strapped for storage space, and your WB setting just do not cut it enough, you acan adjust your Blue, Green, Magenta, Amber offset and continue on JPG.

But, if you want to reproduce high end quality, keep the RAW. AT a wedding I will ony shoot the most important moments in RAW and the rest JPG

[poolstok]

Here's an example where I corrected my camera's colour by adding 2 stops of green and 3 of blue.


Later

Johan

[Black Ricco]

Shooting RAW is like shooting a digital negative while shooting JPEG is like shooting a digital polaroid. With a digital negative you can do wonders in a digital darkroom. I don't know about the Rebel but with the 20D you can capture a JPEG, with a choice of six levels of quality, and a RAW file at the same time. That's very cool because you can always trash the RAW files if there's nothing special, but you're covered when you capture that unexpected winner

[Curtis N]

Raw does allow for quick colour correction, butif you know your PS and understand colour, you can correct afterwards (although it takes more time)
Poolstok -
If I email you the other 100 jpegs can you fix them for me too? The cast would really appreciate it.:)

[Curtis N]

Shooting RAW is like shooting a digital negative while shooting JPEG is like shooting a digital polaroid.
I like your analogy.

[BigRed450]

The easiest way to correct the WB in any JPEG image, no matter what the light conditions, is in Levels. Simply choose the "white point" dropper and click on a known white area i.e. a white shirt then "save" this adjustment in the Levels dialogue box. Or you may choose to use the "Black Point" or "Midpoint" droppers if there is no known white. For the next images you can simply make an action and batch process the rest of the images or bring each one up and "load" the levels adj used for the first image. Jpeg are not near as hard to work on as some think either, but in the end RAWs are faster, easier and will yeild a much better quality image.

[poolstok]

Curtis: LOL! Do they pay? No, but once one image is corrected, you can use the match colour function on all the others - or like BogRed suggests

Later

Johan

[bellemel]

Hey Symes i did exactly the same thing, except that i didnt know anything about RAW. So I mucked around yesterday and using my raw converter program (that came with my camera), I was blown away by the difference, and then just as qucikly devastated when i looked thru my jpegs that couldve been just as stunning...oh well i'll just have to get onto taking more piccies. Love the website and shots people!

[BlueTit]

I use raw 90% of the time now, originally I used jpeg mainly and yes you can do much more with raw and the final result is better. Use jpeg for shots you know you are never going to print or are not that important, but for everything else use raw as it gives you far better options to tweak or even rescue.

[dave_bass5]

Just a quick question for the pros if thats ok.
i have been shooting raw for a few weeks now and not having much trouble with it using C1 pro.
C1 pro has a great feature where you can set certain corrections in one shot and just click on other shots from the browser and apply the same settings without having to open them.
Is it possible to do the same with PSCS2 and jpg's? maybe using Bridge. i dont want to create an action, just to be able to select as many images as needed from a browse window and to have the corrections applied.
thanks for any help

Dave.

[Bullseye]

From an Amature's point of view:
I recently shot about 400 pictures at a dog conformation show. Since I wasn't very experienced with RAW yet (only had the camera 3 days) and had concerns over the capacity of my 2GB card, I decided to use large JPEG instead. BIG mistake! While I did indeed need the extra capacity that using JPEG gave me, I had the usual WB and/or exposure tweaks and correcting took forever! I mean days of working on the pictures. Add to that the slowness of PS CS1 (on my dual processor 1.05ghz PC anyway), and it was just a mess. Even with scripting I devoted way too much time and effort.

OTH, I just did another dog event over two days with about 380 pictures in RAW. I use the Raw Shooters program and like it the best so far, even over Photoshop. I can now correct the pictures in a fraction of the time it would take using JPEGs and I'm not risking corrupting the picture while I do it. No more using a .PSD file with correction layers to preserve the quality of the final version, and the huge increase in storage space it requires. I can easily rescue some pretty horiible exposure problemss when shooting in RAW. Maybe the software is part of the issue, but I'm finding that it's much easier to correct the pictures when using RAW. Now if I could just learn to remove the need to correct them in the first place...

[d'homme]

You can add the photo filter (blue) in PS if want get rid of some of that cast.

[Nightcrawler]

Just a quick question for the pros if thats ok.
i have been shooting raw for a few weeks now and not having much trouble with it using C1 pro.
C1 pro has a great feature where you can set certain corrections in one shot and just click on other shots from the browser and apply the same settings without having to open them.
Is it possible to do the same with PSCS2 and jpg's? maybe using Bridge. i dont want to create an action, just to be able to select as many images as needed from a browse window and to have the corrections applied.
thanks for any help

Dave.

In PSCS2 you can select multiple images for opening in RAW, and then in ACR 3.1, you can change one image and then apply a particular setting or the whole group of settings to the rest of the pictures. You can even have it copy a custom curve to other pics as well. You can also batch convert now in ACR. It is a big improvement to processing RAWs in Photoshop. Ever since I got PSCS2, I haven't even used RawShooter.

[tim]

You can also batch convert now in ACR.

Can you explain this please? The only way i've discovered to batch in ACR start photoshop to do the work.

[slin100]

Poolstok -
If I email you the other 100 jpegs can you fix them for me too? The cast would really appreciate it.:)
All is not lost with JPEGs. If you can figure out a basic set of levels and/or curves changes that color corrects one of your images, you can batch process the rest with the same changes. It may not be perfect, but it should be a substantial improvement.

[Curtis N]

All is not lost with JPEGs. If you can figure out a basic set of levels and/or curves changes that color corrects one of your images, you can batch process the rest with the same changes. It may not be perfect, but it should be a substantial improvement.Thanks. I'll give it a try when I have time.

[roman_t]

i shoot with raw.
convert with c1pro or acr v2.4.
today i've tried ps cs2 demo with cr v3.0. i found c1pro better processed image in auto setting.
adobe camera raw was auto too. i'm looking for the best way to process images for b&w prints.
maybe someone out there has found it already? share pls.

[ryan_kalani]

Mike, I'm sure you will get various opinions on this. Here is mine.

CR2 is the file extension for a RAW file. That means the image file is "straight from the sensor" with virtually no processing, modification, or compression. If you are any sort of a purist, this will be of interest to you. However, once you transfer the files from the CF card into the computer, you need to convert the RAW file to make it usable to normal desktop applications, so you may want to end up with a TIF or a JPEG. Most RAW converters allow you to view and tweak the file before actual conversion. By "tweak," I mean modify the apparent exposure, contrast, and color balance. Additionally, RAW files from most of our cameras are 12-bits. TIF is a good format for editing purposes, since it is non-compressed and does not continue to degrade with continual savings (like JPEG does). TIF 16-bit is good if you have huge amounts of disk and memory, and if you intend to make big changes. TIF 8-bit is good enough for mere mortals. However, at the end of the day, if you are publishing to the web or trying to attach to some email, you'll convert to JPEG format. I hate to convert to JPEG until absolutely 100% of any editing changes are done. JPEG is 8-bits, and once you are there, you would not want to go "back up" to 16-bits (since the damage is already done). One advantage of converting to JPEG in the computer (not in the camera) is that you can control the degree of JPEG compression. You can compress it hard if it is a less important file, or you can compress it gently if it is a very important file. In the cameras that most of us have, JPEG options are few. Also, as I mentioned, continual JPEG saving causes tiny image detail to slowy disappear. If you never print anything large, then the small differences won't show. However, if you do print large, the small differences can be seen, and maybe you simply don't like to compromise.

If space were terribly expensive, then I would understand the need to make some compromises. However, memory and disk space is cheap.

---Bob Gross---
Nice write up