Digital cameras forum: RAW vs. JPEG

It is all about having total control of picture processing.

Some cameras also have a TIFF format for uncompressed images.

Here are two links that do a pretty good job of explaining jpg, tiff, raw:

http://www.dpreview.com/learn/?/key=compression

http://www.dpreview.com/learn/?/key=RAW

...

http://www.faqs.org/faqs/jpeg-faq/part1/section-13.html notes the LOSSLESS JPEG.

http://www.faqs.org/faqs/jpeg-faq/part1/index.html is the full FAQ with many references to fill up a second noggin.

Bob

due to compression jpegs lose information every time you perform a manipulation and save - each save causes compression. To avoid this TIFF is a better option. It is possible to convert both RAW files and Jpegs to TIFF. It is equally possible to print from either jpeg or TIFF - but jpeg is the more universally acceptable. Lots of programmes can open jpegs - some cannot open TIFFs so for web use jpeg is the standard - in photographic terms what you see on your screen is c**p so file quality is unimportant. Similarly my regular photo lab prints from 300dpi jpegs with excellent results and I've had glossy mags use jpegs from a sample disc rather than ask for the RAW original (RAW and TIFFs are bigger files - hence the popularity of jpeg) and the jpegs reproduced just fine. Why shoot RAW at all - for extra control and for file size when you need it. I use it for social group photos - PR - anything where egg is on the face if it ain't perfect - but I rarely need to resort to the RAW file because the jpeg is nearly always good enough - my camera records RAW and Jpeg simultaneously - jpeg for quick viewing/processing and RAW if /when it's really needed. I shoot a lot of sport and would never dream of using other than jpeg - I also shoot travel for magazine and library use and RAW is on all the time for that so I can offer bigger files when/if required - might as well have the top quality as all it costs is extra storage space on cards and discs - travel means dumping to a laptop regularly. Best thing would be to try the camera you have in mind before buying - in both modes and have a couple of real prints made - only you know what you want to achieve - some "purists" insist on the highest numbers and the biggest this and thats and a lot of it is bunkum - some purists take c**p pictures - never lose sight of the picture.

Regarding RAW vs JPEG Formats...
There seems to be a general growing consensus...

RAW takes up entirely too much memory which severely limits the number of shots you can take.

RAW is too slow to load into camera memory which means no action shots can be taken.

Many camera functions such as Bracketing, Multi-shot, etc are not available when shooting RAW which again means no action shots can be made.

Using noise removal software such as Noise Ninja 2 works better on JPEG files as RAW has to be processed before you get an image...
- Noise removal software works best on images that have not been processed in any way as the processing makes changes to the pixels that distorts the noise removal process.
- Generally speaking, noise removal is usually not as successful with RAW files as it is with JPEG.
- As there are no standards for RAW (each camera company does it slightly differently) noise removal software does not work on RAW files.
- The RAW file has to be converted to a TIFF (or JPEG) before the noise removal software will work and then the file has to be converted back to RAW.
- Why go through all that for some slight, very small, hard to detect improvement that RAW is supposed to give?

Yes, RAW does allow you to make all changes to the image with RAW editing software but why spend a lot of time doing that when the camera will automatically do it for you with JPEG?

Most people are hard-pressed to tell any real difference between RAW & JPEG images after they are processed.

Other Thoughts About JPEG...

The general feeling is that if you always shoot in the Fine (highest quality) JPEG mode, that a few saves after editing the JPEG file will do no real noticeable harm.

After Noise Ninja 2 becomes available as a Photoshop plug-in, I will be able to do all editing to the image with just one save after all the editing is done. This will not effect the image in any noticeable way.

Another thought is to never edit the original JPEG image... work on a copy only. This way you will always have the original to go back to if you somehow mess up the copy. Good advice for any format.

General Comments...
RAW does have its place and some very advanced users may find it very rewarding to spend a lot of time manipulating a RAW image to get that very last ounce of detail out of it; however as they say... "Beauty is in the eye of the beholder".

RAW is not so much about the format as it is about the kind of person that uses it.

There are certain users that may indeed find the advanced features of RAW to be very rewarding.

However, for someone like myself (advanced amateur) who wants all of my cameras features to function most of the time, takes hundreds of photos at a day outing, does not want to forgo action or spontaneous shots, does not want to have to keep changing back and forth between RAW and JPEG to get ALL my shots, does not want to carry 5 to 6 times the amount of memory, does not want to wait most of the afternoon to download hundreds of 17MB RAW images, does not have endless amounts of time to take and process hundreds of images, does not like constantly transferring from one image form to another (RAW to TIFF to JPEG) and is not an aspiring Ansel Adams, then RAW is simply not my cup of tea.

Most amateurs do not have PhotoShop CS, but like myself simply use as many of the automated features in a simpler (and cheaper) program like PhotoShop Elements II.

My camera is a Sony 828 8 mega pixel. At the Fine quality and 8 mega pixel settings this is the first thing I run into with RAW...

The time to store mages on my MicroDrive... 2 seconds (JPEG) vs. 15 seconds (RAW).

The size of file... 3 Mb (JPEG) vs. 17Mb (RAW).

I view all of my images with ACDSee image management software but, all of the RAW files in SRF format (that is what Sony uses) are not nearly as clear as any of the JPEG's, in fact, most are downright blurry; this I believe is due to the RAW interrupter that ACDSee uses (as there are no standards for RAW) and most likely is not the fault of RAW itself. This does however put one more roadblock into the use of RAW (for me) as I am not giving up ACDSee as it is one lovely program.

I also see a lot of hype about the RAW format...
Case in point...

One of my friends just bought a new Olympus 770 digital 4 mega pixel pocket camera. For last Christmas I gave him a one year subscription to a wonderful magazine called PC Photo which he loves to read. The other day he said he was thinking about shooting all his images in RAW. I was shocked! Now here is a guy that is still using the 16 MB memory card that came with his camera as memory is too expensive. He has absolutely no imaging processing software on his computer as he does not have any time to use it. He is a total novice, never makes prints, all shots are only for viewing on the computer or for e-mail yet he wants to shoot RAW. Now that is industry hype working at its best.

If, and when RAW conversion technology improves in the future, I hope that one area of improvement will be a standardization of the RAW format; maybe then there will be some real advances in the format as all developers will be working on improving only one version of RAW. When that day comes I will take another look at RAW.

Until that day arrives, I will stick with JPEG.

But, that is just me.

Since you are experienced with film shooting, it might be easier to think about digital like this: A RAW image file is your original transparency. It is the file you will keep as your "original" image just as you would file away your original slides. You will always have that first generation original to revert back to whenever you need it. JPG is for web use. I don't know any industry that accepts JPG format accept the web. Yes, there are portrait photogs out there who shoot JPG, but I wouldn't go to the expense of learning digital with a DSLR if I was going to shoot JPG. You can get the 8mp compact camera and get the same quality JPG that you get from a 6mp DSLR. I have been shooting stock for two years, this past year being exclusively with Nikon D100 and D70 DSLRs. I always shoot RAW, even for my personal photos. You never know what you might want to do with an image in the future. If you shoot JPG, you are limiting your ability to use these files again later. www.pipershots.com

Hi Pathos- I'm a professional photographer who used to stick with film but now I find I prefer digital. I'm using the Nikon D100, would recommend you buy DSLR rather than fixed-lens. Now to your question: first you must understand that digital cameras do NOT see color. Each pixel only sees brightness, and has a red, green or blue filter over it. A RAW file has only the density information from each pixel. By shooting RAW, you do the conversion to RGB in your computer later, rather than having the camera do it on the fly. If you shoot JPEG, then pixels deemed to be irrelevant are discarded, hopefully recreated in a reasonable fashion. So, shoot RAW, get Adobe's "Camera Raw" plug-in for Photoshop, then you have incredible control over the creation of your RGB file. Then, rather than save as a JPEG, you are better off saving as a TIFF file- no compression. My camera is only 6 megapixels, and high-quality 8x10s are no problem. Another great piece of software is Genuine Fractals, which allows you to "res-up" your files if need be, and does a much better job than if you just added pixels to a file in Photoshop. Hope that helps!
Brad Milliken, Palo Alto, CA
fotobrad@pacbell.net

To preface this response, I only have a small amount of experience with digital still photography (I work a lot with digital video and audio).

From my understanding, RAW is a lossless file format representing the uncompressed information as recieved from the CCD(s). In my experience this format CAN be proprietary (depending on the manufacturer) and thus difficult to import into photo manipulation software with out the appropriate plugins or software specific to the camera (although this may not always be the case).

In my experience editing and dynamically processing AUDIO provides the best end results if I wait to apply any form of compression until the end (much like converting to the lossy format JPEG in digital photography) .

In a lossless world I can take a value 5 and apply some process whereby I divide by 2 and end up with 2.5. If I apply the same process again in this lossless world, 2.5 then becomes 1.25. If I end by translating this to a lossy world where non-integer information is thrown out this manipulated value becomes 1 (a pretty close representation of the true value 1.25).

On the other hand, in the integer-based lossy world described above, following the same process the value 5 after the first manipulation becomes 3 (since 2.5 would round up to the nearest integer 3). After the second manipulation (on the value 3 NOT 2.5 since we're operating in a lossy world), our value now becomes 2 (not as accurate).

As you can see applying all manipulation to digital information while maintaining a lossless environment throughout the process yields the most accurate representation for the end result.

If you will be manipulating your photos perhaps converting from the RAW format to a more universal .TIF, .TIFF lossless file first before applying any manipulation and saving in this same lossless format throughout your manipulations might be the best choice. Think of these post-processed files in the TIF format as your negatives to be archived. If a client or colleague needs to have the files emailed you can then open these uncompressed files and save as JPEG for easy uploading/downloading and more versatility for viewing across different platforms. By doing this you can always send the higher quality TIF files by snail mail on a CD-R.

Hi Pathos,

You have quite a few important questions. I'll do my best to answer them one by one.

You say you want a camera that can give you high quality, sharp 8x10 prints. If that's the case, you will want to buy a camera with at least 6.9 megapixel capabilities. Here's how it works: Your 8x10" print needs 300 pixels (tiny squares of color) per inch to look great in print. That computes to 20.6 megabytes (MB) of data. To know if a camera can produce that much data per photo, multiply the megapixel capability (6.9 for example) times three. 6.9x3=20.7MB, so you will be safe for your 8x10" prints. An 8 megapixel camera will certainly do the job well for you.

You ask if it is necessary to go RAW. No, you can use the JPEG format for saving your images in your camera. The advantage to RAW is that you would have the ability to tweak your exposure and color balance for each image individually before "setting" the final image in digital form. That's a huge advantage for people who aren't right on target with their exposures. Digital photography has far less latitude for exposures than traditional print film photography. Digital images have approximately the same latitude as traditional slide film. If your exposure isn't right on target, you're in trouble. RAW gives you the chance to correct exposures in better ways than Photoshop can do for non-RAW images.

JPEG format is exceptional for compressing image files. It's also problematic after a while. Depending on what you want to do with your photos, JPEG may work. You can open and close JPEG files forever without problems IF you don't change anything within that file. However, if you do retouching, cropping, or other photo manipulation and then re-save the file as JPEG, you're actually throwing away a bit of color information. I've heard that it's safe to open, change and re-save JPEGs 5 or 6 times, but after that you may start seeing image degradation. Therefore it's safest to save JPEGs in another format (say tiff or Photoshop) while you're working on the image. When you're satisfied with your results, re-save the image to JPEG format. So whether you keep images in JPEG or not will depend on how many times you expect to open, change, and re-save your images.

Hope this information helps.

I recommend that you read Real World Camera Raw with Adobe Photoshop CS by Bruce Fraser, ISBN 0-321-27878-X

The average photographer would have no reason to use RAW.

If you are a professional or very serious photographer you could find RAW useful.

Many of the camera settings which were applied to the RAW data can be undone when using the RAW processing software. For instance, sharpening, white balance, levels and color adjustments can be undone and recalculated based on the RAW data. Also, because RAW has 12 bits of available data, you are able to extract shadow and highlight detail which would have been lost in the 8 bits/channel JPEG or TIFF format.

Example: You are dissatisfied with the color of a photo taken under florescent lights. You did not use the correct white balance setting. Instead of trying to create the correct colors with PhotoShop; with RAW software you can actually go back and change the white balance to the florescent setting.


...