Jpeg embedded in Raw ,, Why?

[JZaun]

I am still trying to learn raw , I can convert raw to jpeg with file brouser when I save it or when I save the tiff file,, what use is the jpeg embedded in the raw file. It seems to me it just takes up space. Does anyone use it.?

Still learning :D

JZ

[Scottes]

Is there actually a JPEG *embedded* in the RAW? I've always wondered this. I know the THM is really a tiny JPG and contains most of the EXIF info. If the JPEG is embedded, I wish it weren't. I guess it can be used for preview stuff, but I'd rather save the [minimal] space and [minimal] time since it's a complete waste to me. As far as I know.

[PacAce]

Yup, there's a real JPEG "file" imbedded in the RAW file. That's reason why the RAW file size varies with the type of JPEG selected. Although I don't really use it all that much, when I'm in FVU and want to review the images, I will select the JPG images to display instead of having FVU convert the RAW for display. Using the JPEG image is a LOT faster.

I also know that there are a few people who will extract the JPEG files when working with "tons" of raw files just for proofing and reviewing with, say, clients. Once they decide on which ones they really want, then they'll go convert the raw to tiff so they can work on it. THis saves having to convert every one of the RAW file, whether they need them or not.

[Scottes]

OK, that makes some sense now. I must have missed this since I've never installed FVU, and CaptureOne builds previews. Yup, they're useless to me.

[Longwatcher]

What Pac Ace said.

I use the enbedded jpegs (shooting RAW with medium jpeg) as proof images and to give a copy to models at the end of the photo shoot.

It takes mere seconds to extract the jpegs from the RAW files, where as it takes forever to convert the RAW files into something useful relative to the expectations of the models. in otherwords the embedded jpegs use the auto white balance, contrast and sharpenning commands of the camera so the image is close to ready to go, but the RAW is raw and needs to be post processed in order to make it look nice. There is also the fact that to convert the RAW images to jpeg takes about 3-4 seconds per image on my computer, meanwhile extracting the embedded jpegs goes at about 15-30 images per second. Huge difference when taking over 500 images a session.

Also because PS does not have a good image slide show capability, which I use for seeing which images I want to spend effort on, I use a different program and need jpegs for that, so might as well embedd them right off the bat.

Finally using medium jpegs mean I can usually get all of the session on on e CDR to give to the model, so while she is changing I am doing my final download, extract and writing the CD and it is ready to give her within 5-10 minutes of the end of the session versus when using RAW only it took about 45-90 minutes to produce a CD copy of the session.

(note the jpeg is in the file, but is not part of the RAW image itself, which is also embedded in the RAW file as RGB channels - If I understand the file format correctly)

Thus why I personally use embedded jpeg version of RAW. Of course I have have enough CF card capacity and eith my computer or picture pad that it would take a lot of effort to run out of memory space.

[Rosalie]

i have just started shooting Raw, processing in ps cs.

When that 'raw processing panel' comes up in ps with all settings like exposure and white balance, how do you know HOW MUCH to change exposure, or which white balance to choose, as i think its so subjective depending on the image (some obviously have a 'right' wb setting). Just like any ps post processing work is subjective, i find though that in the raw panel is ps i sometimes, or very often cant make up my mind which wb to choose or whether to lighten or darken the image, or by how much?...

are there any tipps anyone can give me, maybe general rules. Is it best to do most of the colour correction in the raw panel as it doesnt degrade the image, or should i do that once in proper ps.? how about sharpening, in raw panel or in ps (unsharp mask)?

just some quick tips would be great from ppl with more experience! :)