I've been using the "unstable" RT3.1.2. Unstable doesn't mean RT3.1.2 doesn't work. Instead it means all the new features show up in RT3.1.x to be admired and tested out. Developers want feedback to fix any bugs and to hear ideas for improvements.
So this post will be about an undocumented way to use RT3.1.2 which I think photographers with older computer who have cameras that only shoot jpegs may find useful. Why older computers? I have up two up here in the computer room: a year old, 64 bit laptop that fits all the RT specifications, and a three to four year old 32 bit desktop where I still do most of my photo work.
Why do I use this old relic? Because I have an ancient, heavy, $20 at a garage sale, monitor hooked to it. A Sun Workstation monitor that was designed for profession photo-work, one that I can color manage so what I see on the screen is exactly what I see in the print. To replace my antique with a profession grade flat screen would set me back about $1500, money I'd much rather spend on neat stuff like lenses.
What's the downside of a 32bit machine? Memory or the lack of it. I have 3GB of RAM memory in the desktop, all a 32 bit computer can use. Window takes back 1GB to run itself. Other stuff like antivirus software gobbles up another GB. Finally when I covert my D7000 16.2 mp 14bit RAW file with all the fancy features RT provides, I can need up to another GB of memory. So I have to watch my memory usage.
How? It's all in the manual and on the RAW Therapee web site. Read and enjoy. Follow all the steps and you won't have problems as long as your machine has a decent amount of memory. If it doesn't, read this blog post.
Either way you use RT you won't be disappointed. Open source and always free it is posed to become the best RAW converter available. A head to head RT vs ACR6 is in the planning stage. Plus as a special bonus to you jpeg shooters, it's also a super good jpeg editor.
Enough with the prologue. Here's the step by step.
1--Download and install RT.
For RT3.1.2 http://www.visualbakery.com/RawTherapee/Downloads.aspx
For RT3.0 http://rawtherapee.com/downloads
EDIT This unofficial 'single image' mode works only with the 3.1.2 and the newer and renamed RT 4.0 version. Download at http://www.visualbakery.com/RawTherapee/Downloads.aspx
2-Open up your jpeg directory with your favorite viewer and pick one that needs editing. I use IrfanView. It's an excellent, widely used and free program.
3--Optional Hit control.alt.delete to bring up your task manager. Click on the bottom tab and then on the performance tap. The bottom window shows how much memory you are using. While not needed it doesn't hurt to watch what is going on for the first few times you use RT. At the moment I'm using 1.16GB.
4--Bring up the windows menu and click on open with. The first time you do this, you may not find rawtherapee.exe on the list of programs. In Vista choose default programs and find RT3.1.2 in your list of installed programs. Don't click the always open box. In XP this may be different and you may need to consult a help file.
5--Open the file. RT will pop up on your screen with your jpeg ready to edit. What you won't have is the file browser--this can take several minutes to load as it caches your files--or the batch queue. You won't need either one since you are editing one jpeg at time. At the moment I'm now using 1.34 GB, an increase of .18GB and several times less than the official way would need.
6--Edit your jpeg. Then hit the 'save current image' icon down at the bottom. In the window that pops up name your file, select your RT conversions directory, jpeg quality and set the save immediately button. After a short time your converted image will show up in your RT conversions directory. Because of a minor bug the ready light will come on earlier than it should so don't depend upon it. During this process my memory usage peaked at 1.58 GB
Don't use the 'create folder' tab. There is another bug and the folder isn't created. I also click the 'add' tab to put my RT conversion folder in the 'places' list. That way I don't have to navigate through a tree of folders next time I use RT.
7-Close RT. You are done. Now my memory usage is back down to 1.20 GB, near what I was using when I started to write this post.
8--What happens if you don't close RT. The next jpeg you open adds to the existing memory usage. If you convert a few files in a row you will run out of memory. I just ran two larger jpegs with some complicated RT calculations-- using the new punchy modes-- and hit 1.96 GB. So remember to close unneeded RT windows.
How well does RT work with jpeg. I was shooting with one of my manual non cpu lens--a classic Vivitar Series1 35-85mm f2.8 lens--at an opening reception a few week ago. Below is a jpeg I took to set up my manual settings for the correct exposure. I guessed wrong by two stops. Plus the lighting was tricky because the off white gallery walls were brighter than the subject.
This is what I ended up with after adding 2 stops of exposure, creating the proper tone curve in LAB mode and sharpening with the Contrast by Details routine. Note that you won't find the last two operations, LAB mode or Contrast by Details in any other jpeg editor. No matter how much you spend.
And finally here is the finished image after two or three minutes work.
Quick, easy and then finished.