The term Raw implies that the raw file contains all of the data the image sensor has generated, and without any adjustment or post capture processing. JPEG files on the other hand are the result of the camera's post capture processor chip automatic adjustment to what the camera manufacturer thinks should be a good picture in terms of brightness, contrast and color balance. And then JPEG compression throws out all information that is assumed to be redundant to reduce file size. Finally with most cameras the default colorspace for JPEG output is sRGB which can further reduce the color gamut by as much as 30%.

The bottom line is to have the convenience of the camera making all of the decisions for you rather than color correcting and adjusting the image yourself, saving in JPEG format reproduces only a fraction of what the image sensor captures in subject information. In other words the tax you pay for the convenience of JPEG is getting just a reduced part of what you paid for in an expensive, many megapixel image sensor in terms of what it really can actually capture and record.

Thanks for the info. But if you have to convert to JPEGS to get photos printed does it still make scense to shoot in raw?

If you can't tell the quality difference between snapshots and professionally made prints, probably not.

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Thanks for the info. But if you have to convert to JPEGS to get photos printed does it still make scense to shoot in raw?

RAW is not an image file format in the way that TIFF, JPEG and PNG are. It is rather a container for the "raw" output of the camera's sensor - a vehicle it to transport it into an application where the user has far greater control of how it is processed than by using the camera's firmware and controls. This means that one can very accurately - or to taste - set the white balance after the fact, adjust the dynamic range of the image and to a certain extent even set the exposure after the fact and prior to opening the image. It provides a very sensitive environment for the photographer to achieve his or her vision.

TIFF, JPEG and PNG are picture delivery formats for viewers. RAW is a data format from which photographers work. It is not meant for public viewing. There is a preview generated by the software in order to determine the settings, but no actual picture at all as with JPEG. It does not actually become a digital picture until the RAW loader opens it into the image processing program.

If the application supports 48-bit (16-bit per channel) workspace, there are 65536 steps in each channel (red, green and blue) between the lightest and darkest values in that channel. With JPEGs there are only 256, so if there is much correction needed, gradients can become banded and rounding errors can produce visible artifacts.

Most RAW files are 12-bits per channel, so 48-bit workspace offers lots of headroom in which to process them. As they come from the camera, RAW files natively have 4096 steps per channel. They can handle somewhat higher contrast subjects, so if exposed to preserve highlights, they allow the photographer to dig out significantly more detail from the shadows.

Of course once processed, the final image can be saved as any viewing format you wish - just never save over the RAW file. It remains as something analogous to the negative from a film camera. It is the original data that you can always go back to and reinterpret as your skills improve.

Shoot JPEGs if you are shooting in environments with normal lighting and average contrast. If you plan to really learn photography as a serious pursuit, then shoot both for now. The JPEGs will give you easy access to your images. Specially if you are shooting under extreme conditions, shoot a couple of shots on RAW as well for later once you at a point of skill and knowledge to make best use of them.

The downside of RAW is that it takes skill to use effectively. The files are much larger than JPEGs, so use up storage card and hard drive space. Processing in camera is generally significantly slower, fewer shots can be done as a "motor-drive" sequence and RAW is also slower to load in the computer.

My first digital cameras were too early to support RAW and there are many shots that I would love to have in RAW now. The contrast range was beyond what a JPEG could handle, were shot under mixed light and were basically failures in JPEG format. Had they been shot RAW, all the shadow detail that JPEG could not contain would be recoverable. Working in 48-bit workspace, using layers and layer masks, each light source could be individually balanced in the areas that it lit, and the layers seamlessly blended, so a well balanced final shot would be a breeze to achieve. Furthermore, even though the corrections in this case would be drastic, the layers would show no effects of the heavy processing they underwent and the final result would be absolutely smooth with no artifacts.

If you are content to be a casual shooter, then JPEG alone might well be adequate. However, if you are shooting a cityscape at night, architectural interior. specially if there is a mix of light sources or a spectacular sunset, do a couple of RAW shots as well, just to keep in the bank until you are ready to deal with them. I REALLY wish that I had been able to do so with my early digital work. Some very nice compositions would have made some glorious prints, had JPEG not been the only format available.

Thanks for the info Larry. I am starting to understand what this RAW vs JPEG stuff about.

It is not RAW vs JPEG - it is actually about where the raw sensor data is processed.

You are always shooting raw. When you set the camera to JPEG, the embedded processor and firmware are used to interpret the raw data off the sensor to make a JPEG, using the settings you have made on the camera. Once the JPEG is completed and saved to the card, the raw data is discarded.

Saving the raw data as a RAW file, allows you to move it to be processed elsewhere. The RAW loader - whether Raw Shooter Essentials, Adobe Camera RAW or software bundled with the camera - is substituted for the camera's processing. The loader software is both far more sophisticated than the camera's firmware and has the full processing power of the computer as well. It allows the photographer to interact at leisure with the data for a much higher degree of fine tuning.

I would like to suggest reading Photoshop CS2 for dummies by Kevin Ames. It is 5 books in one, covering all the way from camera set up and techniques through processing RAW files. I am not sure how relateable all topics will be to your software but most would be. He explains in easy to follow language what all these terms mean and why you would want to use one format over another.
You could also download a trial version of Photoshop after reading the book to practice what you learned and then apply it to your other software or come over to good side.

Thanks to you all. I am starting to understand and have shot some RAW and worked with the files and I like what I see so far.

Simply put, a RAW file is like having a digital negative for much more manipulation after the exposure is made. Hence if you shoot in JPG, you throw out the negative and merely have a print. Make sense?

Photo Larry
Photo Larry Website

Yes is does. Thanks for the help>

Makes no sense. I've been shooting JPEG for years and have never had a problem making excellent prints. If convert the original JPEG to an uncompressed format, you can edit it to your hearts content. What do you think photographers were doing with cameras before there was a RAW option?

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if you shoot in JPG, you throw out the negative and merely have a print.

Maybe you can look at it in these terms to make things more simple: Your camera always sees in RAW, you can choose if you want the image processor in your camera to decide what the scene should look like (JPEG) or you can take control and decide that for yourself (RAW editing and then conversion). Personally, I moved to RAW 2 weeks after getting my DSLR and I never looked back.

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Makes no sense. I've been shooting JPEG for years and have never had a problem making excellent prints. If convert the original JPEG to an uncompressed format, you can edit it to your hearts content.

Actually you're wrong there because if you convert JPEG to an uncompressed format it doesn't make a difference because JPEG already threw away the content it deemed unnecessary. As a matter of fact just opening a JPEG file in Photoshop (or any other editing program) translates it into bitmap which is a non-compressed format, but once the data is gone, it's gone, you can't get it back, no matter what you convert into. You can't edit data that is not there. That's why RAW allows change in White Balance and Exposure (You can fake it in JPG but it shows). And JPEG is also destructive, the more you save over a file, the more it compresses and reduces quality (I'm sure you must have heard of JPEG artifacts?). Plus RAW works in 16 bit, JPEG only 8. JPEG is the most popular existing format of hundres of formats (TIFF was the best, but the Amiga computer sort of died), but also the worst in terms of quality, and because of its popularity it's been hard to replace it (The Joint Photographic Expert Group (JPEG) is working on a new version JPEG2000 and Microsoft is trying to push its own proprietary format).

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What do you think photographers were doing with cameras before there was a RAW option?

What do you think printers were doing before picoliter droplets and 12 ink tanks? People were also taking photos in 2 megapixels when 12MP or higher didn't exist. Would you say that we should keep doing that because quality can't improve? Technology evolves. JPEG is over 20 years old. For more info READ: JPEG 2000

Luca