basic RAW processing help

[mapgirl]

First of all, sorry for asking such basic questions, but using the search tool didn't come up with anything that actually helped enough. And second, please assume I am slow and dumb when you answer or provide a link to a tutorial.

I am shooting RAW for the first time and finally located the correct plug-in AND figured out how to get the image to the editing page (whew!).
I am using Photoshop Elements 4.0 and I shoot with a Canon Rebel XTi.

1. Why would I select a depth of 8 bits rather than 16 bits?
2. When I have finished doing the processing I want in that part (the RAW part) of Editor, do I click on "Open" to transfer this to a regular Editor window to do more? And then do I save to JPEG?
2a. And do I lose less by doing this than by shooting directly as JPEG rather than in RAW?
3. Why would I click "Save" in the RAW processing box and save as a .dng?

That's all for the moment. Thank you in advance for any help you can offer!

[Daisie]

2. Yes. Even if you don't want to edit more, click "Open" if you want to save as a JPG.

[Jim Bryant]

Here...if you are using Photo Elements 4.0, I did a google search and this might or might not help you.

good luck!

http://books.google.com/books?id=G17...sult#PPA209,M1

[Nicole]

Originally Posted by mapgirl

First of all, sorry for asking such basic questions, but using the search tool didn't come up with anything that actually helped enough.

Don't worry, no matter how many times we try, the forum really doesn't like to search 3 letter search terms. If you're trying to search for something that's only 3 letters (e.g. raw, HDR, etc) then I highly recommend using Google's advanced search which lets you search a particular site because it pulls up way more answers.

Originally Posted by mapgirl

1. Why would I select a depth of 8 bits rather than 16 bits?

A simple answer is because you can't save to jpg if you're using 16 bits and not all editing / filter options are available in 16 bits.

Originally Posted by mapgirl

2. When I have finished doing the processing I want in that part (the RAW part) of Editor, do I click on "Open" to transfer this to a regular Editor window to do more? And then do I save to JPEG?

Yep, open will open it in Elements so you can do the rest of your edits.

Originally Posted by mapgirl

2a. And do I lose less by doing this than by shooting directly as JPEG rather than in RAW?

I'll leave this answer to someone a little more technically minded.

Originally Posted by mapgirl

3. Why would I click "Save" in the RAW processing box and save as a .dng?

Well, .dng is Adobe's format for RAW photos. It's supposed to be a more open format, but basically it can open in Photoshop and some other programs also open it. It's supposed to be a way to keep your RAW photos without depending on continued support for your camera's file format.

Hope that kind of helps a little.

[Palladius]

1) I'm pretty sure Photoshop can't edit 16bit pictures or, at least, can't perform its full array of editing functions. As far as I can tell the extra information makes editing pixels insanely complicated. Also, most of the time it's fairly useless information as far as a finished product is concerned

2a) You should lose exactly the same amount of information... the good thing about RAW is that you decide what information should be discarded rather than your camera

3) .dng is Adobe's version of RAW... it hopes to make it standard for everyone, but that's what all companies hope for their formats. If you save as .dng you wont discard any information... you'll be able to come back later and keep tinkering. Rather like saving a picture you've been working on as a photoshop project file...

[mapgirl]

Originally Posted by Palladius

2a) You should lose exactly the same amount of information... the good thing about RAW is that you decide what information should be discarded rather than your camera

First of all, thank you all so much! Everything everyone has posted thus far has been enormously helpful. But I have a further question for Palladius (and whoever else has an answer): How am I deciding what information will be discarded and what isn't? I (sort of) understand that the RAW format gives me everything. So when I make selections/edits for light and color and resolution and then save as a JPEG, what gets tossed out? What is then saved/protected?

[Samanax]

Originally Posted by mapgirl

I am shooting RAW for the first time and finally located the correct plug-in AND figured out how to get the image to the editing page (whew!).
I am using Photoshop Elements 4.0 and I shoot with a Canon Rebel XTi.

1. Why would I select a depth of 8 bits rather than 16 bits?

In Elements you can't use layers if you have a 16 bit image. If you want to use layers you have to go with 8 bit.

But you can convert from RAW using 16 bits, do some edits and corrections in Elements and then convert that edited image to 8 bits so you can do layer work.

Originally Posted by mapgirl

2. When I have finished doing the processing I want in that part (the RAW part) of Editor, do I click on "Open" to transfer this to a regular Editor window to do more?

Yes, you click on "Open Image" in ACR to send the image to Elements.

Originally Posted by mapgirl

And then do I save to JPEG?

Yes.

Originally Posted by mapgirl

2a. And do I lose less by doing this than by shooting directly as JPEG rather than in RAW?

Yes, you get more from an image if you shoot in RAW and edit and save to JPEG yourself rather than have the camera do the JPEG conversion/compression for you.

Originally Posted by mapgirl

3. Why would I click "Save" in the RAW processing box and save as a .dng?

The RAW file from every camera is specific to that camera, so in essence each camera is using a proprietary image file format. .DNG (Digital Negative) is supposed to be a kind of universal image file that keeps all the data intact from the RAW file. Because it's a universal file format, you could share the RAW file with others who may not have to correct RAW converter for your specific RAW file. I don't use .DNG.

[Samanax]

Originally Posted by mapgirl

But I have a further question for Palladius (and whoever else has an answer): How am I deciding what information will be discarded and what isn't? I (sort of) understand that the RAW format gives me everything. So when I make selections/edits for light and color and resolution and then save as a JPEG, what gets tossed out?

Stuff you didn't want.

Originally Posted by mapgirl

What is then saved/protected?

The stuff you wanted.

Don't try to get too deep into the mechanics of the editing software, just concentrate on working your images so that they come out the way you want it. The RAW file doesn't get changed or edited so you can always go back to the original image information if necessary. What you're working on when editing is a proprietary Adobe file that is totally separate from the RAW file.

[Palladius]

So when I make selections/edits for light and color and resolution and then save as a JPEG, what gets tossed out? What is then saved/protected?

An excellent question and, as Samanax points out, rather a complicated one... I'll answer as best I can.

Camera sensors are rather more complicated than you might think... without getting too indepth, they don't record light in the same way a film negative does. They record a huge amount of very basic information (such as, how many photons hit this specific green filtered pixel), and then interpret that to form a coherent picture.

As an analogy; it's been to the supermarket and bought loads of ingredients, but to get dinner you need to pick the right ones and put them together in the right way. Generally, cameras are pretty good at doing this, and will generally knock up a decent spaghetti bolognese all on their own. But maybe you like more garlic in your bolognese, or maybe you fancy shepherd's pie instead.... if you're shooting in jpeg, you may not be able to do that, because your camera threw away your potatoes when it decided to make spag bol.

I may have overstretched that analogy a touch!

If you want a more indepth and technical explanation, I can recommend this site: http://www.cambridgeincolour.com/tutorials.htm

[mapgirl]

Originally Posted by Palladius

As an analogy; it's been to the supermarket and bought loads of ingredients, but to get dinner you need to pick the right ones and put them together in the right way. Generally, cameras are pretty good at doing this, and will generally knock up a decent spaghetti bolognese all on their own. But maybe you like more garlic in your bolognese, or maybe you fancy shepherd's pie instead.... if you're shooting in jpeg, you may not be able to do that, because your camera threw away your potatoes when it decided to make spag bol.

I may have overstretched that analogy a touch!

Not a bit! It's quite vivid. And as I love to cook, it makes perfect sense to me.

And Samanax, all the info is very helpful. It's all beginning to come together in my head. Thank you.

One more question, if I might: I shot my test pictures in RAW and JPEG. My Canon has a setting to do both in a single shot. Now that I'm feeling a bit less uneasy about RAW, should I just shoot RAW alone? Or do the dual type because I can? What would be the advantage?