For the past several months I have been playing around with GIMP and making tutorials that had a big Wow Factor. Today I wanted to create a little show and tell series on a more normal workflow.
After getting over the initial overwhelming feeling that I had to learn a bunch of new software all at once, I am able to relax and explore some of the raw editors available for all platforms (Linux, Mac, and Windows).
UFRaw has been around for quite some time (since 2004) and even has a GIMP plug-in so that you can do your raw edits and then import into GIMP, so I thought I’d try that out first. You can get UFRaw here (the plug-in is available for Linux and Mac only).
For this image, I did some minor raw edits in UFRaw. Then in GIMP I adjusted the levels, the contrast, added a split-tone, then sharpened the image. Later I cropped the image (see opening image).
I took this image with a 40mm lens so I knew it would need to be cropped in order to see the locust. Before I cropped it, I made all the changes so that I could crop as many different ways as I wished and I wouldn’t have to redo all of my edits.
UFRaw Walkthrough
First I opened up my image in UFRaw (conversely if you have the plug-in you can open the image in GIMP and the UFRaw window will appear)… there is a really good UFRaw manual here…
There are several things you can adjust here. To adjust the exposure 
you can move the slider to the left or right. You can also click on the indicate boxes to find out if you are clipping the whites and/or the blacks. If you are clipping these the image will flash white (for underexposure) or black (for overexposure). Learn more about the other icons in the exposure section in the UFRaw manual here.
Items of note… the circular arrow 
will take you back to the default setting of each option, the gear icon 
will make an auto adjustment.
Along the top you will see a series of icons. Each of the icons is a tab were you do different adjustments…
In the white balance 
tab, you can adjust white balance and denoise (see image above).
In the Grayscale 
tab, you can make your image Black & White by various methods; lightness, luminance, value, or by color (channel mixer)…
In the lens 
tab, you can make adjustments to fix any distortions your lens may have created… in this case, my lens is not known (or doesn’t make distortions ?), but I could also try to look up a lens by clicking on the lookup icon 
and then choosing a lens…
In the base curve 
tab, you can manually adjust the curves… you can save an adjustment and load a previously saved adjustment too…
The next tab is color management 
, I don’t personally do anything in this area, but if you understand color management in this way, there are available adjustments…
Next you can correct luminosity and saturation
, which means that you can adjust the black point (there is an auto gear button), the contrast, and the saturation. You can also adjust the curves again…
If you were wanting to crop or rotate your image, then go to the next tab 
, where you can adjust the orientation of the photo and/or crop it…
In the save tab 
, you can set what kind of image you want to save these adjustments as (jpg, tif, png, ppm, fits)…
Note that this screenshot is slightly different from the previous screenshots. If you open UFRaw directly then you will get the save options. If you open a raw file with GIMP, a UFRaw plug-in will open… it looks slightly different (there are no save options). 
For the plug-in , once you have made your adjustments in UFRaw you would click on the OK button and it will import into GIMP. If you open in UFRaw directly, you can save your image or you can click on the Wilber (GIMP) icon 
and it will open your image in GIMP.
Lastly, the EXIF 
tab, will allow you to see all of the settings from your camera for that image…
This is going to be an ongoing series, in the next installment I will make my initial adjustments in UFRaw and then import into GIMP.
Did you miss part of this series? Check out my Workflow Series page.
Until next time…
~nic
Photography by Nic 
“The next tab is color management , I don’t personally do anything in this area”
I spend a lot of time in this area adjusting gamma, linearity, and exposure for the midtones.
There’s a tab depending on your ufraw version in which you can spot select a color and increase or decrease it through out the image.
Thanks, Mark, I’ll have to explore the color management tab further. Thanks for explaining it a bit better. 🙂
It is really interesting too see photo editing being done with different software.
Thanks, Ben. I hope you try out the different software. 🙂
Hi Nic. Thanks for the great tutorial. What was your final print max. I’m Having problems with that in some of my cropping.
Hi KC, if I understand you correctly, you are wondering about cropping and then being surprised that the image you print out is smaller than you expected. To be honest, this particular image I knew would have to be majorly cropped because I used such a wide angle lens when my subject was so small, so I never intended to print this image. If I had had my macro lens with me I could have filled the frame with my little subject and then I could print very big images and wouldn’t have had to crop.
But your question is more about how to control that max print size when you crop, I think. I know that in Photoshop it is easy to accidentally create a very small image by putting values into the cropping fields rather than using an aspect ratio. For GIMP you can choose an aspect ratio too (which is how I tend to crop), but you can also fill in a width or a height field in pixels, inches, percent, etc. Personally, I use aspect ratio and if I intend to print the image I try not to crop very much at all. A huge crop, no matter which way you do it will cause you to loose a lot of pixels with means a smaller print.
For this image, had I not cropped it, I could print 11.5 x 17 inch because my image is 3465 x 5202px [at 300 pixels per inch (ppi)]. Once I cropped this image it can now only be printed as 3 x 4 inch because it is only 821 x 1233px (at 300 ppi). Typically, I further scale down my images to 500 x 333px for my blog, for that very reason, if someone wanted to print an image of mine off the web it would only be 1.5 x 1 inch image (at 300 ppi).
The thing about choosing a ppi for printing varies depending upon how you intend the viewer to see the image, it is all about viewing distance. If you want the viewer to hold the image and look at it, then you’ll need at least 300 ppi… but if you wanted to put it up on a billboard, then you could get away with a much smaller ppi, like 10 to 20 ppi. Check out this page for the math and a better explanation.
I don’t know if I answered your question. But hopefully this was helpful. 🙂
You absolutely answered my question. The reason I asked is I’m getting a few shots on iStock but was surprised at the max print size. I do upload full pixels but have done some cropping so they were smaller than I thought they would be. Appreciate your helpful answer 😀
Oh good, I’m so glad I could help. 😀