Altering photos in Photoshop

If I pull up a RAW photo in Photoshop and make changes to but decide not to save it, will this alter the image in any way? I was told simply making changes to the photo even if not saved or saved under a different name will alter it permanently. Not sure if this is true though. Would appreciate anyones input on this

The changes that you make to a CR2 file are non destructive, anything that you do to it is simply saved as instructions for the output to an editable format. This only applies to RAW files and if you start to make changes to tif, psd or jpg they can be permanent depending on how you make them.

The Prime Principle that governs all RAW converters is that the RAW image data will never be altered.

P2P wrote in post #10718867
If I pull up a RAW photo in Photoshop and make changes to but decide not to save it, will this alter the image in any way?...

Are you talking about pulling it up in Adobe Camera Raw, or from ACR, opening the image in Photoshop? The fine difference is adjustments made in ACR WILL be saved, but non-destructively, and you can clear all adjustments and start from a clean slate at any time. If you send the raw image from ACR to Photoshop, you can make all the adjustments you want, but if you simply CLOSE the file without saving to an image format like JPG or TIF, nothing gets saved and you're left with the raw image as it was.

Everyone, thanks for your help with my question.

@ChasP505,
My scenario was opening it up in Photoshop from ACR. Thanks for your explanation. So I think I can safely say that as long as you dont save to a different format (JPEG etc..)then the RAW format of the file is not altered while making changes to it in Photoshop.

P2P wrote in post #10721126
Everyone, thanks for your help with my question.

@ChasP505,
My scenario was opening it up in Photoshop from ACR. Thanks for your explanation. So I think I can safely say that as long as you dont save to a different format (JPEG etc..)then the RAW format of the file is not altered while making changes to it in Photoshop.

Even if (and you can only) save to a different file format in PS, you will not alter the RAW file. So far as I know, you cannot save to a .CR2 or its sidecar .xmp file from Photoshop.

Hen3Ry wrote in post #10721412
Even if (and you can only) save to a different file format in PS, you will not alter the RAW file. So far as I know, you cannot save to a .CR2 or its sidecar .xmp file from Photoshop.

True. In fact when you open a raw file from ACR into Photoshop, aren't you actually looking at a temporarily created TIF file? I could be wrong.

ChasP505 wrote in post #10721453
True. In fact when you open a raw file from ACR into Photoshop, aren't you actually looking at a temporarily created TIF file? I could be wrong.

You can set CR to open the file in PS as a JPEG, TIFF or a PS file.

Actually, when you open a cr2 from Camera Raw into Photoshop you do not open it as an image file format (jpeg, etc) -- ACR renders the image, but Photoshop still shows it as a CR2.

What you do have in ACR are settings for Color Space and 8/16 bit depth that you can change. But a new file/format only happens when you do a Save As in the editor, or when you so a Save in Camera Raw.

Thanks everyone.
This has been very informative.

ChasP505 wrote in post #10721453
True. In fact when you open a raw file from ACR into Photoshop, aren't you actually looking at a temporarily created TIF file? I could be wrong.

tonylong wrote in post #10722920
Actually, when you open a cr2 from Camera Raw into Photoshop you do not open it as an image file format (jpeg, etc) -- ACR renders the image, but Photoshop still shows it as a CR2.

What you do have in ACR are settings for Color Space and 8/16 bit depth that you can change. But a new file/format only happens when you do a Save As in the editor, or when you so a Save in Camera Raw.

+1 to Tony. The image is in PS's internal work format, a sort of 16 bit bitmap, because at that point it is only a temporary memory entry.