Wednesday, July 18, 2012

Rah Rah for RAW!

In my previous Post, I was a little hard on Linux for the way all of the Open Source RAW Developers was putting a hard Magenta cast into the highlights of my RAW Files. I suspected this was because the Canon Medium and Small RAW Files (the ones I prefer using) were not being handled well by the underlying DCRaw Code. Happily, my suspicions were confirmed, as yesterday I shot a bunch of RAW + JPEG's on my way to Cape Enrage in Albert County, New Brunswick, using the full-sized RAW setting. With full-sized RAW, I didn't notice even a hint of false Magenta in any of the pictures, and so until DCRaw can fix this bug, I know what I have to do, and I'm happy to be using all Open Source RAW Developers again. You may want to review my RAW vs. JPEG Post for a refresher.

Since that last Post, I've learned a little more about Open Source RAW Developers, and also reviewed some things I already knew. First of all, I was reminded how each Camera maker has it's own proprietary RAW Code, which troubles some people who fear obsolescence. There is one well known non-proprietary RAW Code, which is Adobe's DNG, making it a standard of sorts, much like Adobe's standard for Printed Text, which is the well known PDF.  But not many Cameras use DNG, instead they pack their own RAW Software for Windows and Mac, meaning that if you switch brands from Canon to Nikon, you have to start all over with a completely different RAW Developer.

This is where Open Source Software (read "Linux") comes in. Most if not all of the RAW Software Packages that are included with Linux are based on one "pioneering" Program called DCRaw. The DCRaw Package has no Graphical User Interface (GUI), so you need to know how to do Linux Command Line stuff in order to use it. But, because none of us want to do that, a number of other Linux Projects have built some awesome GUI Software using DCRaw as a foundation. There are UFRaw, DarkTable, RawTherapee and Photivo to name a few. Each of these Projects keeps abreast of all the various camera's proprietary RAW Code. and frequently update their product (and DCRaw itself) with the latest changes from Canon, Nikon, Sony, etc. This means OpenSource Software takes a lot of the worry out of obsolescence, in much the same way as PhotoShop and LightRoom do, except that OpenSource is all available at no cost, usually for both Linux and Windows Operating Systems.

So, once again "The Folk Photographer's" question - should I be using RAW if my camera has it? I'll proceed with a demo that might help you decide.

Yesterday, on our little outing through Albert County, New Brunswick, a beautiful composition happened right before my eyes as I was driving. I quickly applied the brakes, and had to back up a little bit, but it was really worth it. I had my camera set to shoot a Standard (large) RAW and a JPEG at the same time;

Here is the JPEG straight from the Camera:


Here is a Conversion I did from the RAW file with Photivo for making a nice print:


And finally, here is a High Dynamic Range (HDR) I did from the same single RAW file, also using Photivo:

 HDR isn't really my cup of tea, but I like to try it out once in awhile. The cool thing about Photivo is that it can do it with just one file, not in the usual way of blending two or three different exposures into one HDR exposure.

So, I prefer using RAW because it allows a much greater range of final results compared with the limited possibilities of working with an already locked down 8-Bit JPEG (RAW Files use a Bit Depth of 16, which greatly extends the possibilities. I've used several of the DCRaw based programs, and here are my very quick impressions of each:


  • UFRaw - real quick and easy, intended primarily for making broad exposure and Gamma adjustments, and exporting the adjusted result to GIMP for further work. RAW does not include an actual RAW to JPEG converter, but once exported to GIMP, you simply "save-as" JPEG, or whatever other format GIMP can handle (which are many). One thing I really like about UFRaw is that, to process a lot of files, you can "select-all" from your file system, and UFRaw will automatically open each one in turn - as you export one to GIMP, it will follow by opening the next one in the sequence.
  • RawTherapee - this one can be as quick and easy, or as complicated as you want to make it. It includes a File Preview Tab which shows all of the RAW Files stored in any given Folder, and you simply double-click on the one you want to work on. The Canon Digital Photo Pro (for Mac and Windows) works exactly the same way, but RawTherapee has a lot more features than DPP. One of the best features is a library of Presets, which you can use with a single click to enhance the appearance of your picture. Often, it's enough to open a picture file, select one of the Presets, and then save the result, which will automatically export your picture as a JPEG to whatever Folder you have pre-specified. If you don't like any of the Presets, you can build some of your own, simply by manipulating the manual control sliders until you get the results you want, then "Save_As" a Preset Template, for quick single-click re-use on other pictures. Oh - one other thing - RawTherapee automatically saves a little Text File with every picture, showing every step you took to "develop" your picture. This can be disabled if you wish
  • Photivo - this one doesn't have a "quick and easy" way about it. However, it is by far the most powerful of the three. It has an overwhelming number of control sliders, all arranged in a common sense set of Tabs on the side-bar, and by adjusting these (altogether which look like the dashboard of a Boeing 747), you can get really amazing results from your original dull looking RAW files. It is oriented to working on pictures one at a time, with no provision for bulk-loading. Another great thing about Photivo is that it can be used to greatly enhance JPEG, PNG or TIFF files, not only RAW's, although naturally, RAW files still contain the greatest latitude for adjustments.
For me, it's Open Source all the way. I see no point in buying PhotoShop and other expensive Windows Software - I'd rather invest in a nice Printer, or more lenses.

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