JPEG to TIFF?

I came back from a recent trip and realized that I shot a number of photos in "family vacation" mode (i.e. JPEG instead of RAW) and now I want to work up the images...

Is there any real advantage to convert those JPEGs to TIFF to minimize the degredation I would otherwise experience as I work the file? Has anyone done this? Downsides?

Jamie,

Open the jpegs in your image editor and save them as TIFF files. You can then work on the TIFF files without losses. Keep your JPEG files just in case.

-P

Just to clarify what Preston said, as you know JPGs that are saved and re-opened several times experience degradation. So if you are only going to open the JPG for editing once or twice I don't think you'll gain much benefit from converting. I personally wouldn't bother converting.

But if you're doing heavy editing, you might get a bit of an advantage by going to 16-bit TIFFs, which will allow you to make finer adjustments to colors, but you'd have to be really digging in to the image for this to matter. The drawback there would be a big increase in file size (and the time to convert), but if you're used to RAW, that's probably not a problem.

Here's an example of JPG degradation :

http://www.andrewkelsall.com/how-shocking-can-a-jpeg-be/

I know I've seen other good ones, but I couldn't find any...

I wouldn't bother converting to TIFFs.
If you save a JPG at maximum quality in a top-quality editor, you can resave it many, many times before you'll start to notice significant degradation. On the other hand, if you save it once using MS Paint, it'll look like a pile of crap immediately.

You could always make copies of the original JPGs and have them to revert to if you find a working version does get degraded...

If you use PS for postprocessing, why not save the file as a PSD? (if the editing has layers)
Or, a lossless PNG? (no compression)

Another way around the JPG deterioration is to "Save As" instead of "Save." The Saved-As file is a new entity, and it won't be any more degraded than the JPG it started out as (it will keep all your editing). Then you just keep on Saving-As, creating new undegraded files.

Everybody is correct but nobody has mentioned one thing. Perhaps you already know this since you shoot in RAW, but anyway. You've already "thrown away" tons of data by simply having the files saved as jpg. RAW capture is 16bit (actually 12 or 14 depending on camera) and jpg is only 8 bit so you've already gone from 4096 levels of tonality down to 256. You've also aready done some "cooking" by the camera for preset things such as contrast, saturation and so on. Taking it back to 16bit tif cannot "undo" any of that because it's only converting back from the 256 you have. You'll never have the flexibility that you have with RAW but it is what it is so make the best of it. The simplest course is to just work on a copy of your jpg so the original jpg is preserved. Then save the adjusted copy as whatever you like. I agree that psd makes the most sense to preserve the layers without radically increasing file size such as you would with tif.

Kenn - As I've seen and the link I've posted demonstrates, I wouldn't open, edit, and save a JPG more than maybe 3 or 4 times, and that's pushing it. And MS paint, if it's saving badly, is simply saving with a very high amount of JPG compression. The JPG standard format and quality is the same regardless of the program, but it provides for various amounts of compression. And there is a trade-off between amount of compression, and image quality. So perhaps MS Paint is just highly compressed.

Sure, but the link you've posted doesn't demonstrate the effects of saving a JPEG at maximum quality / minimum compression repeatedly. Doing it the way he did, I'm surprised how good his final picture is. Saving a file at 95-100% quality ten times would more likely yield the difference visible between the initial and first save in that fellow's experiment.

Good point Kenn - I missed the part about random compression amounts (seems like an odd choice). I wish I could find the other, better ones I've seen. I suppose a lot depends on how large you want to be able to view/print the file as well. The smaller the more saves you can get away with.

Jamie: I am a big believer in leaving my original capture or scan intact and using master files and targeted files. Here's another workflow if starting out with a jpeg image...

Open original jpeg in PhotoShop
Save as PSD or TIFF (this will be your Master file)
Duplicate the image
Close the Master file
Edit the duplicate image (This will be a 'Targeted file'
Save the file with layers intact (Don't flatten)

If you're going to use for the web...
Duplicate targeted PSD file
Close the targeted file
Size this duplicate as needed
Flatten this image
Edit>Convert to Profile... and select sRGB if the image is not already in that profile, If it is, click Cancel
Sharpen to taste
File>Save for Web
Choose your 'quality' (compression) level
Save.

I know this sounds like somewhat lengthy process, but it really is easy to do. Now, you have your untouched jpeg and a layered (and unsharpened) Master file from which you can create targeted files for printing, or for the web.

As David says, multiple saves of jpeg files will show degradation very quickly. My personal rule is: Work up the image and then save it as a jpeg only once. If I need to work on it again, I will open my targeted file, work on it, save it as a new jpeg.

Perhaps I am being overly picky, but when I save my jpegs for the web, and especially for my web site, I need them to be of the highest quality I am able to achieve.

Cheers,

-P

Thanks for the great feedback! That's why I love these forums!
I tend to always work from a copy and "save-as" versions, so it sounds like I'm not doing too bad. I like the idea of saving a .psd file, that should help too. That is a new approach that I'm starting to get comfortable with.
Thanks for the workflow suggestion, Preston!