I can view my raw files using GQView and they look great. But when I load the same raw file in Gimp, it looks "flat" and "muddy." It helps when I load the custom color profile for my camera, and it helps some more when I tweak the images. But I still can't get the picture to look as nice as it does in GQView.

Detailed information: my camera is a Canon EOS Digital Rebel XT (350D). I'm running Ubuntu with Gnome, Gimp, DCRaw, and UFRaw. Most of my software was installed using Synaptic so it may not be the most recent.

It frustrates me that Gimp can't make my picture look as good as GQView can. I assume the fault is with UFRaw, but I don't know how to fix it.

Does anyone know how to fix this?

Thanks!

Are you sure it's only a problem with gimp?
What about loading the raw files using a variety of other image viewers to determine if it's truly GIMP that is at fault.

Well I said in my post that the pics look great in GQView. I don't know any other programs that will view .cr2 files. Good ol' Canon, making things difficult again.

If you read my post carefully you'll see that the problem isn't with Gimp per se, it's with UFRaw. If you know a better way to convert .cr2 files, I'd love to know what it is.

I went back into Windoze and used Canon's conversion program to see what it was doing. It gets the exposure curve from the picture. UFRaw doesn't seem to be able to do that. I guess I can create my own exposure curve, but that's not really a fix.

I found the solution: don't use DCRaw. If you have a great-looking raw image and don't really want to do any color correction, use exiftool. Many raw formats include a built-in jpeg "preview image" that is the same size & picture quality of the original file. DCRaw and UFRaw should only be used if you actually want to do image correction.

Thanks Geeman for answering my post! I hope this solution will be useful to others.

Koppie,

Two weeks ago I discovered ufraw, and I am very satisfied with it. I have a Canon D300 Rebel. Before, I was using dcraw, and I was struggling forever to get the balance and the exposure etc. right. Once I imported the picture in Gimp, most adjustment space was lost as Gimp already uses 8 bit depth. As opposed to ufraw which uses 16 bits until the picture is imported in Gimp or saved.

Not that dcraw is bad, ufraw uses dcraw, but ufraw provides a nice front end.

Just because I am trying to learn, and would like to see where others struggle with, would you mind sending me an example of a picture which was good in your opinion, and which was also processed with ufraw, and unsatisfactory in your opinion?

I also have used "convert -unsharp" for sharpening the pictures. The result is MUCH better than with the internal JPG converter. For months I had seriously been doubting the quality of my lenses, because the pictures were always unsharp at *any* distance.

I use "convert -unsharp 1.0x0.5+200+0.1" for pictures 1024x1536 which were converted by the camera, or JPG at 1024x1536 produced by ufraw. Sharpening before resizing has not been succesful.

jlinkels

I have also a Canon digital slr, yesterday I tried converting the cr2 RAW images using Canon's own software (on Windows). Worked well, of course - their hardware, their software. Then I tried (with the very same picture) this same trick in Linux (with dcraw & ufraw installed). Results?

- With GQview, as already said, the picture looked good, but of course I couldn't do anything about it
- Trying to import it to Gimp using ufraw produced a picture that was dark purple toned and unsharp. Interesting? I tried several times and couldn't get it look nearly as good as with GQview, so I really wonder how UFRAW could do good work..

So, it seems I'm stuck with Windows again (thanks, Canon, you made software for Windows & Mac, but not for Linux). At first ufraw seemed like an answer, but it's clear now it doesn't work for me..not at the moment, anyway.

If you know how ufraw works better, please share your information.

It is little bit difficult to talk about images in text-only mode

What input profile do you use? If you use the D10 profile which is available on the internet, inage quality is different. My experience is that especially the red color is strongly affected, and the pictures look muddy and unsharp. However, if you look carefully the colors and the contrast look *very* natural, and they are not unsharp. But this is not what we want to see in a picture! We want to see brilliant and vivid colors, and ultrasharp images, and that is what P&S cameras produce and perhaps Canon's own software as well.

I don't like the hi-fi color profile either, and I use the ufraw standard input profile, and accept the sometimes redder than red colors in the picture.

Please note that you *have* to sharpen your pictures as a consequence of the AA filter in the camera. I have the best results using ImageMagick's convert with the unsharp parameter at "1x0.5+300+0.4" setting. GIMP settings for unsharp seem to be different, and it is easy to overdo it with the unsharp filter. Without sharpening the pictures look blurred.

To be honest, I have never seen my own pictures using the Canon converter. I don't own any Windows machine anymore, and I would not even know how to install software as I don't know the difference between a registration process and a trojan installation.

Have you tried to save the images directly to PNG or JPG from within UFRAW? That is what I do almost exclusively. But from what I remember the results were not different from opening it in GIMP. Note that there is a difference betweent the sequence CRW -> PNG -> sharpen -> JPG and CRW -> JPG -> sharpen -> JPG

Can you put your RAW image somewhere so I can download it? Together with what you get when you save the image from UFRAW as JPG, saved from the GIMP as JPG and your UFRAW profile?

jlinkels

Let's set the basics straight first....

.raw file is what the name suggests: raw data generated when the light fell on the photochip of your camera. It's unprocessed data and the image is supposed to look uncolored and muddy. What will become a nice image needs one more step of processing that data, applying white balance, adjusting contrast, noise reduction and even some sharpening. That is done by camera's firmware so you get the preview on camera's display and (if you choose to save both types) and jpg file. Also that preview is included in the raw file.

Ususally, jpg's are nice and satisfactory, but one may want to do corrections on their own. That's where having raw file comes handy as it's uncompressed and with all the data possible so processing will not degrade image quality. It's not Canon being difficult but giving you the possibility.

AFAIK, GQView doesn't really show raw files, it just opens the jpg preview inside them. If you like them, you can set your camera to record jpgs and get much more images on your memory card (jpgs are like three times smaller). If you want to have possibility to edit the files (raws can even be safely "pushed" up if you were shooting in low light conditions) then keep the raws. There is not many raw processing apps for Linux, but you should try DarkTable. Not only that it gives the big set of tools to "develop" your raws it also imports camera's white balance so you have a good starting point. Btw, developing raws takes a bit of knowledge and practice (and takes time, it's huge amounts of data being processed) but it's a part of the job.