what are the .xmp files?

[VibrantMindDance]

Occasionally, when i save an image it also creates an .xmp file. I have no idea what the point of them are, and i cant even seem to open them if need be. Could anybody tell me what, why and how i can stop them from being created?

[hw771230]

From what I can figure, those .xmp files are just your camera raw settings for that image. They take up very little space, so I just leave them. If you do a batch process I believe there is an option to not produce those files. I use CS2 though, so you may experience something different.

Caleb

[gldiana]

Hi,

if you want to see what's inside an XMP file all you have to do is open it with a word processor (Notepad in Windows works just great), making sure that you do not change anything (unless you're good enough to understand this macro language).

XMP Macro language is similar in a way to HTML and a command looks something like this:

<crs:BlueSaturation>+2</crs:BlueSaturation>

So, when you open your favorite RAW file editing program, the program will create a text file (the XMP file) that contains instructions on what to do with that photo. For example, you move the slider of the Blue Saturation level to +2 and the program will add the line above inside the XML file.
One of the best and biggest characteristics of RAW editing (unlike any other format) is that the editing is non-destructive, which means that the modifications you do are not done to the photo itself but rather to an external file (the XML file) so when you open Photoshop or Lightroom or whatever it is you use to edit RAW the program will look for a file with the same name of you photo but ending with the suffix .xml
If the program does not find that file then it will show the RAW file the way it was captured, if it finds the file it will apply the modifications written in it. The non-destructive nature of this format means that you can go back to a photo you had edited years before and remove those modifications without ruining the photo. The best part is that all these modifications (which translated into an unlimited amount of UNDO, unlike, say, editing a JPEG where undo is limited by your memory) can be done/undone in a non-linear way.

Caleb, you want to be careful. If you spend an hour making modifications to a photo and delete the xml file for that photo you will have to start all over again. As far as the batch process goes, I'm not sure what you are referring to, but I assume you are talking about batch processing the export of a number of RAW files into JPEG, at which point the xml file does not get created because it's not needed since there is no modification to the RAW file.

Look at the .xml file as your best friend rather than as an annoyance.

I'll be happy to answer more questions if anyone needs further clarifications.

[hw771230]

Luca,

It sounds like you know this stuff better than me. Like I said I do not delete these files. When I do a batch process (convert to jpg) these files are indeed produced. There is an option to not save them (but I always do). I keep a jpg of nearly all my RAW files so I can sift through photos much more quickly when looking for a specific shot, or for culling if I am not shooting in RAW+.

Caleb

[Bonish Photo]

I made the mistake when I first started shooting in RAW to delete these xmp files because I didnt know what they were. Then like Luca mentioned, after working on one image for quite some time, I went back to it a few days later and had to start from scratch.

Dont delete the xmp files!

[gldiana]

Not sure, Caleb. What software do you use? I only use Adobe Lightroom which is much more powerful than Camera RAW in Photoshop.

[hw771230]

I use Camera RAW in CS2. I wish I had the budget for Lightroom and CS3, but who doesn't. When I got CS2, and started using camera RAW it was like a whole new world.

Caleb

[gldiana]

Yeah I hear you. I was a betatester of Lightoom since the alpha version so I got it for a good price, and a little mention on Adobe's website

[Bonish Photo]

WOW Luca, that is pretty sweet.

I'm gonna copy that, photochop my name into it and send it to my brother. He went to school for Graphic Design and lived working on Photoshop for 4 years of his life. That and a bunch of other programs that we'd never use for photography.

But we have always joked how cool it would be to have your name on the start up screen, like Thomas Knoll - The first name you see while Photochop is starting up

[hw771230]

Very cool Luca,

I'm going to try Lightroom and see how long it takes to get addicted and get a full version.

Caleb

[gldiana]

hehe,

thanks Caleb. You'll get addicted pretty quickly
Don't forget to use the "L" shortcut to show you the photo surrounded by grey or black background. It's very effective in making you see your photo as if it was in a lightboard.

[VibrantMindDance]

Hey. Thank you all very much for your responses. I guess the deleting of these mysterious files was a mistake. Now i know! I dont get these files with all the images I edit. Is there a reason for that?

Also, do you guys feel that Lightroom is a better tool for photographers than PS?

[gldiana]

Hi,

there is really no comparison between Photoshop CS3 Camera RAW and Lightroom. It's like comparing Photoshop Elements with Photoshop, and I'm even being pretty generous there. PS3 Camera RAW is a very slimmed down version of Lightroom, I'd never regret buying it. The only program that can compete with LR is Apple's Aperture, but that's only on Mac.

I'm not sure why some of your modifications are not appearing in the .xml file, maybe they're not directly related to the file itself? have you tried asking in the PS/LR forum on the Adobe's website? You'll find a wealth of information there.

[51773]

Am I the only simple minded person? In the old days, with DOS, after we would edit, we would simply insert a letter or number into the file name to indicate it is a modified version of the original, thereby not effecting the RAW photo at all. True, you end up with two copies, one as shot, one as modified, however it is a simple, easy, and less teckie way of making sure the original is kept pure. You can also group and sort on the "Modified date" or 'Creation Date" to pull up only the files you have worked on.
Am I missing an advantage with XMP files?

[gldiana]

An MXP file is a sidecar text file, and it's the only way to modify a RAW file non-permanently. You can go back to it 10 years later and still eliminate some editing that you don't like anymore or even remove all editing done, in the order you prefer. It's value is unquestionable.
Also because of its nature (text file) it's takes very little space on the hard disk as oppose to have several edited version of tiff or jpg files that take a considerable amount of space.
The old DOS trick of adding a number to the filename to indicate a new version does not work with a RAW file as the RAW file itself cannot be modified. And that's a very good thing, no risk of damaging permanently the source.