RAW vs. JPG vs. TIF

[John Lovaas]

I just got my first RAW capable digicam- a Kodak P880. My "old" DX7630 finally gave up the ghost after its second, and ultimately fatal, swim.

From a quality standpoint, is it worth it for me to learn how to work with the RAW format? I archive my "finished" photos as TIFs, and memory card and hard drive space is not an issue.

Let the debate begin ;-)

jl

[Darklight]

When I purchased my Olympus E300, then E500, body, I started experimenting with RAW and Adobe RAW converter. It has a steep learning curve to say the least. As it is a sort of "digital negative" at first glance they look a tad bland. This is a good thing! RAW gives you the utmost control over how the image looks in the end. JPEG out of the camera generally suffer from a lot of compression and sharpening artifaction. OK for the web but lousy for serious work. TIFF files, I think, have the same issues but are very large files. RAW files have no post camera processing save for perhaps ISO or some other metadata.

I sometimes shoot RAW+JPEG. That way I get to see what the camera thinks it sees, and the ability to tweak it with the RAW negative. It is important to remember that RAW allows you to have total control over the look and feel of the image. It is your interpretation, NOT the cameras. Sometimes I never even look at the camera JPEG until after I have it looking the way I interpret it. I never want to get biased before I have a chance to work the file over.

One of the best things I've found about RAW and caving is the ability to control the white balance. I use a QPCard and shoot various test shots under different flash bulbs and the like. Then, using Adobe, I find just the right color temp for the shot.



Conversely, white balance adjustment is an easy slider change in Adobe. Often, I'll insert the QPCard into my first shot, when doing say nature work, so I have a reference for later post processing.

I used this technique in the image below. The Meggaflash PF330 bulbs always had a weird color temperature, but I was bale to correct this easily with RAW



I highly recommend the book "Camera RAW with Adobe Photoshop" by Bruce Fraser. It is an excellent primer for the world of RAW.

Here are two non-cave images showing what a RAW file off the chip looks like



and after post processing in Adobe



All the sharpening, color correction, enhancement, saturation, contrast--it's all up to you! To me, keeping the digital negative is very important. A TIFF or JPEG is no better than a paper print, then tossing the slides or negatives in the trash.

[Teresa]

Some cameras have the ability to control white balance in camera. If you've got a mondo digital, RAW is cool.

If not, or if your camera gives you no option,(mine doesn't) just get out of jpeg into a lossless format like TIF as soon as possible. In camera if possible. If not, on the first download save to the computer. I disagree that keeping a photo as a .tif is 'no better than throwing the negatives away.'

Now, keeping .jpgs as originals--another thing entirely.

Wonder when digital cameras are going to take decently exposed photos, so each one doesn't have to be hand-printed and jiggered to get decent results.

The demise of film slides at this time is a tragedy.

[Steven Johnson]

From a quality standpoint, is it worth it for me to learn how to work with the RAW format? I archive my "finished" photos as TIFs, and memory card and hard drive space is not an issue.

I am just a point-n-shoot kinda guy, but I'm friends with one of the engineers on the Adobe RAW processing code, and based on the stuff he's showed me, it looks totally worth it if you are serious about high-quality output. The extra range you're getting from the camera gives you some impressive post-processing capabilities.

[Realms]

Agreed Steve. I see postwork in digital much like that done in the darkroom for film. And for digial, RAW seems to give you a greater range of control than other digital formats. Even shooting on film I was constantly tweaking the end results. No matter what medium you choose to photograph with people will always be tweaking with it.

[John Lovaas]

Are you guys archiving the RAW file that comes out of the camera, or are you saving it as a .DNG file? There seems to be a school of thought that Adobe's DNG format will be the "archival" RAW format for some time to come. I've got the DNG converter, but do not have Photoshop. I've been a Paint Shop Pro guy for all these years, and may have reached the end of the road for PSP.

I'm sold on the amount of information that is stored in the RAW format, but am nervous about the many different "flavors". As an example- the Kodak RAW software that ships with my camera can't open the RAW format file(which has a .KDC extension) that the camera produces! You have to download the latest version of the software from the Kodak site. Paint Shop Pro 9 does not open the P880's RAW files, even though it claims to open files with the .KDC extension.

Kodak's software allows me to manipulate these parameters-

Sharpness
Noise suppresion
Exposure
Shadow/Highlight/Flare
Manual and Auto White Balance

The PC software doesn't provide me with any histograms, unfortunately. The in-camera firmware not only provides me with a histogram function, but also a much more feature-laden white balance interface. Go figure.

jl

[ethan]

I just got my first RAW capable digicam- a Kodak P880. My "old" DX7630 finally gave up the ghost after its second, and ultimately fatal, swim.
From a quality standpoint, is it worth it for me to learn how to work with the RAW format? I archive my "finished" photos as TIFs, and memory card and hard drive space is not an issue.

Didn't I tell you that throwing your camera in the water was a bad idea and it would get its revenge some day??? :P At least killing a camera is a good excuse to buy another - I've been putting off my new purchase for almost a year now.

I don't have a camera that is capable of shooting raw (though I wish I did), but from my viewpoint, as long as digital cameras are using 10, 12 or 16-bit linear-scaled analog to digital converters and JPGs are limited ot 8-bit log-scaled quantization, then you're definitely losing something by storing images as JPG. I would think that shooting RAW would give more capabilites for fixing images in post-processing (which would be valuable to me, as I tend to get a high proportion of imperfectly exposed caving images). Any kind of processing is complicated when working with the non-linear 8-bit representation used in JPG. It should especially help if you're trying to bring out detail in dark areas using a non-linear intensity transformation curve.

It should also give you more flexibility in compensating for improper white balance. The situations where I wouldn't expect it to help much would be very noisy images (e.g. high ISO) where the signal-to-noise ratio is so poor that the 8-bit representation is more than good enough.

Here's a few good links I came across discussing the issue:
http://www.clarkvision.com/imagedetail/ ... sus.jpeg1/
http://www.photo.net/learn/raw/
http://www.astropix.com/GADC/SAMPLE3/SAMPLE3.HTM

[driggs]

RAW gives you the utmost control over how the image looks in the end. JPEG out of the camera generally suffer from a lot of compression and sharpening artifaction. OK for the web but lousy for serious work. TIFF files, I think, have the same issues but are very large files. ... A TIFF or JPEG is no better than a paper print, then tossing the slides or negatives in the trash.

This is not true. Storing your "negative" photo as a TIFF is perfectly fine, and IMHO should be preferred to storing it in raw* format.

Your camera manufacturer's raw format is not the same as my camera's raw format - in fact, they're undocumented in most cases. TIFF is a published standard and so is readable by any photo processing software. A straight raw-to-TIFF conversion is a straight whatever-to-Red-Green-Blue conversion. TIFF is a 16-bit format (vs. your raw's 12 or 14-bit), meaning you're not tossing any information out in the conversion - TIFF has bits to spare. TIFF is a lossless format, meaning that while size may be reduced, no information is lost. JPEG, as has already been well established, is lossy (goodbye information, hello artifacts!) and therefore not suitable for archival purposes.

If your camera can save directly to TIFF (especially LZW-compressed TIFF, which is still lossless), the ability to read these in the future (vs. your manufacturer's proprietary raw format) may be reason to use it even though they can be larger in file size than a raw image.

Disclaimer: I'm not a photo guy, I'm a software guy!

* "raw" vs. "RAW" - it's not an acronym!

[Steven Johnson]

Your camera manufacturer's raw format is not the same as my camera's raw format - in fact, they're undocumented in most cases.

I believe that this is why Adobe is pushing the DNG format for archival purposes... I have not read the spec, but my understanding is that it's essentially a wrapper for the RAW data with metadata describing the format.

[Ralph E. Powers]

what I want to know is how you're able to post GIANT pics here... ? geez