JPG vs RAW

[pjibe]

Hi everybody

I recently bought a SLR 8 MP (Canon Rebel XT) with the option of saving files in JPG or RAW or JPG and RAW. I’‚’‚…‚’‚…¾‚m having essentialy 3 questions :


- I presume it’‚’‚…‚’‚…¾‚s normal when I choose the top quality picture, that JPG file end up with a 3 M file instead of 8 M file in RAW. Wich one should I choose if I want to enlarge some pictures ?

- And what size of enlargement should I expect to be acceptable with this SLR ?

-If RAW exist, if it is a very good output and probably the best for enlargement how come most of the photo lab don't take them. They take TIFF files wich are very often larger files than the RAW files for the same picture.



Thanks

Pjibe

[RTaylor]

RAW files are the best for photos.
A raw file is like a digital negative.
You have much more control to adjust the photo to get better results post processing.
I convert the pictures I know I will print and possibly sell, from Raw to tiff.
Other files I might just upload but not print, I convert to jpg.
If you make adjustments to jpg files, each time you hit save over a jpg file, you loose quality.
Saving over and over on a tiff file, you lose NO quality.
Sometimes I convert from RAW to tiff, then save the web smaller version to a jpg file.

Always keep your original RAW file if you want to keep that file for future use.
If you ever mess up on adjustments saved to the tiff file, you can never go back to undo.
You go back to the original RAW file and start over

In RAW files, the camera software should allow you to adjust your white balance. In a jpg file, most software doesnt allow you to adjust your white balance.

You can try shooting RAW and JPG of each picture then see what you think. But that takes up a lot more room on your memory card.

Have fun

[SMcEvoy]

pjibe

I shot jpeg for the first six months of using my digital SLR and it took some shots with great colour & detail that enlarge extremely well. e.g. http://www.photoswithfinesse.com/Ima...ckcountry.html (And remember it's displayed on my website as a 72dpi jpg.)

I finally got brave and went RAW just after Xmas. (e.g. http://www.photoswithfinesse.com/Ima...plywinter.html ) What it offers is the flexibility to 'fix' exposures if you got it wrong the first time. You can adjust it up to two full exposure stops either way. You can also adjust white balance (at least with my Nikon D50 you can) when you first pull it up too. Where I have found this useful is on things like snowy images that can come out a bit blue. You can change the exposure bias from cloudy to sunny and you get a whiter image - just as an example.

The reason printers won't take RAW files is because basically they are 'unprocessed'. It's like taking a RAW film to the dark room and you have to process it before you can get prints off it.

JPEG and TIFF are processed files which is why developers accept them. The camera determines the colour, tone, white balances and sharpness for jpg's and whilst you can adjust levels and highlights somewhat you can't adjust exposure issues by a lot. One of the arguments against shooting JPG is that the images is compressed before saving it to the card (hence the smaller file size) and you have therefore lost some of the detail. (Note: always use the SAVE AS feature when saving a photo you have made adjustments to. It doesn't degrade your original copy that way. Once you do a plain SAVE, you've overwritten your original (unless you've kept it on the memory card) and you've lost it to work with). When you save your converted RAW file as TIFF you have full pixel value and full colours which is why the file size is huge.

Either way, with a Digital SLR, you will get high quality enlargements. (In fact, with a 3.2 Megapixel non-SLR I was able to successfully enlarge to 12x18 pretty well as long as I brought the original file into the store and didn't submit it online - more compression there.)

If you shoot RAW and save as TIFF, again you have full complement of pixels and colours to play with and probably successfully print up to 30"x40" with minimal quality issues.

I did try comparisons using my kids on a skating rink as test subjects. Whites were whiter and colours were sharper shooting RAW on the same manual camera settings. The skin tones in the kids faces were more detailed and realistic. I believe one might be 16-bit colour and the other 32-bit but am not totally sure on that point.

The drawback to RAW is the size of the file and the fact that every photo has to be post-processed individually. That can be really time consuming. So for my general snapshots I use .jpg (e.g. events at the kids school, the family bbq etc.) But if I'm out shooting the Rockies andmy other gallery shots, I now shoot RAW + JPEG. It means I can print snaps for the album or play around with the ones I'm really serious about and adjust them accordingly. Best of both worlds really - but you do need bigger memory cards for that!

I just got a 2Gb Sandisk Ultra II for $99 at Costco so am fairly well set for this mode - that's in addition to a 1GB and 512Mb! I can take it on vacation now without having to worry about uploading every day. (You'll get about 130 shots/GB in RAW + JPEG mode at the highest resolution setting)

Hope that clears up the mystery a bit.

[pjibe]

Thanks a lot for all that clear information. I'm not quite a beginner in photo but in digital much more. There is all a new language to learn about even if I'm pretty familiar with pc stuff.

So, if I understand well, if I want a good quality picture for enlargement at the lab, first shoot in RAW and secondly transfer it into a standard format and preferably into Tiff in order not to loose quality in compression ?

My DSLR software than came with my Rebel XT has the possibility to work with RAW files and transfer it to JPG or TIFF 8 bit or 16 bit wich I presume 16 is the best ? My 9 or 10 M RAW files come up to close 45M TIFF files.

Do I have to make editing in RAW or in Tiff ? I have more option with Tiff format.

Thanks again

Pjibe

[SMcEvoy]

You would make your editing in TIFF, then do a 'Save As' and save it as a new version. (e.g. Pic#1, Pic#1a, Pic#1b etc.) That will save all your pixels. And 16-bit is definitely more than 8-bit.

I know what you mean about digital being a whole new language. Two years ago when I joined byte I would never have been able to give you that explanation of the hows & why's! I've learned a ton off here.

[ponder]

Suzan,
I shoot almost exclusively in RAW format and the camera converts them to JPG at the same time I download them from the camera. My question to you is how do I save the RAW into a format I can use? I use Adobe Photo Elements and when I want to save the RAW into a different format, all I can save it into is the DNG format and then I don't have a way to convert to TIF or JPG.

Any ideas would be helpful for me. Most times I just keep the RAW as a negative and work with the JPG file instead. I convert it into a photoshop extension and then when I want to post on byte, convert back into a JPG format.

Thanks for your help,

Dave

[SMcEvoy]

Dave, when I plug in my USB cable to the camera and turn the camera on, I use the Windows 2000 File manager to copy the files to a folder on my computer. Once they've finished uploading I end up with .NEF files for the RAW stuff. (I think .NEF may be the Nikon proprietary extension for their RAW files.)

For those, the first time I opened one I right-clicked on it and chose 'Open With' and selected Adobe Photoshop Elements 3.0. (If it doesn't appear in the list then you can click on Choose Program, find it, highlight it, then click the checkbox at the bottom of the screen that says 'always use this program to open these file types.' Once you've done that, you can skip those steps and just double-click on the RAW file in your folders and it will always open them with Photoshop.

After that I get a screen that pops up with a preview pane of my picture and the possibility to adjust my exposure compensation 2 stops in either direction in increments of .33 of a stop. I'm also able to change my white balance on that screen too if I want to. The preview pane changes with each adjustment. Once you're happy with those two settings, you hit OK and it fully opens into PS Elements ready for adjustments. Once you're done with it, that's when you can do your 'Save As' and save it as a TIFF or a JPG. Some people will save as a TIFF before they start their adjustments. Because I keep the original RAW on my computer I don't do that. Hope that helps.

[ponder]

Suzan,
Thanks for the info. I just figured out what I was doing wrong tonight. In Elements 4.0, it opens .CR2 which is the RAW format Canon using as its extension. It first opens the CR2 into a window that allows you to make changes and adjustments in a RAW viewer, but if you click Save, it only allows you to save in the DNG format. If you click Open, it then takes you to the regular Elements format and then you can Save As any type of format you wish. I just upgraded to Elements version 4 from Elements 2 a couple of weeks ago and I'm still not that familiar with all of the new features.

Thanks for all your help!

Dave

[Buddy4344]

Dave,
I shoot with the Canon Digital Rebel. In RAW, my file extension is a CRW extension. Coincidentally, I also used Elements 2 for a year and upgraded to Elements 4. While I like the better features for layers and also love the filing system, it really slows down my older computer. When I had Elements 2, I didn't know how to open RAW files and found some plug-ins that allowed it. The Elements 4 opens 'um right up just as you described.

[nukacola]

how to remove the noises?
If it is possible in RAW

[Aladyforty]

Ive shot in RAW a few times and can honestly say I saw little difference in many shots, if I shot a photo in bad conditions, yes it was worthwhile but as I shoot a lot of wildlife and like to bang off up to 20 images at a time I would run out of card and in the end the workload is even higher once you get the photos into an editing programme. I would bother for some of my shots but on the whole I find jpeg quite ok.

This test between the two forms of shooting is quite interesting

http://www.ics.uci.edu/~eppstein/pix/rawvsjpg/

[shootem]

Hi Guys!
Shooting in RAW your camera makes no decisions. If you like the decisions your camera makes - and always nail your exposures - shoot jpg.
For those that want to make the decisions ourselves (brightness, contrast, color toning, ets.... and want the ability to enlarge as much as our camera is able - shoot in RAW.
Saving your files in .psd allows you to go back and change if you don't flatten the layers. A tiff file unflattened is huge. But a .psd file is very manageable, and like I said, you can reopen the file, click on any layer, and make adjustments. Until you flatten the image. Then save it as a tiff. .psd files are lossless like tiff.
When I started shooting in raw, I would shoot raw + jpg. That way I could "see" what the image "could" look like, because most of the time when you open a raw file, if you aren't used to looking at them, it's a bit dissapointing. You must remember this is all the raw data, unprocessed by your camera. When you shoot jpg, your camera makes all the adjustments, including sharpening (unless you turn it off)
Shoot Raw. Open and Save in .psd. Convert to .tiff when you are certain you will make no more changes. If you mess up, you always have the raw file to go back to. Save the file unsharpened. Open, make a copy, resize for print or web, sharpen, save .tiff for print or jpg for web.

f/64
Happy Trails,
Carolyn

[dandaskew]

Hello Everyone!
You have me encouraged to try shooting in RAW (or NEF as my D50 calls it).

The only photo software that I have is the freebie Nikon Picture Project and a 6 year old Version of Corel photo house that won't open RAW.

I can open the NEF in picture project but from what I can see the manipulation that I can do is minimal. Does anyone have any tips on getting the most out of this software or a free or cheap download that will let me get the most out of my RAWs?

Thanks!
Dan

[Bark4Soul]

Arent raw files huge on the computer?

[shootem]

Depends on the MP of your camera. My Neff (RAW) files open at around 20 MB. If I save them in Tiff, they become around 70 MB, and if I save in .psd (photoshops native)it will depend on how many unflattened layers you have. Some of my files are 200 MB or more. If you flatten the layers they will be much much smaller. But if you flatten the layers, you can not go back at a later date and make changes to existiing layers.
That is why many photogs open, dump dups and duds, then save to a DVD or CD (if they fit) and also to an external hard drive. Then you can open the ones you want to edit without clogging your computers main hard drive. Then save again your worked files on an external hard drive.
When you shoot in jpeg, not only does your camera make lots of decisions (color, contrast, sharpening) but every time you open, edit, and resave, you lose information.
Carolyn