Now that we have looked at color management, layers, and 16 bit processing, we can better compare the alternatives. First, I will mention that Picassa, iPhoto, and many other simple image editors/ artistic enhancers are available. I don’t use them simply because my own needs are beyond what they provide. But they could be perfect for you and your needs. However, I will not be able to say much more about them.
Gimp and Photoshop Elements
Gimp and Photoshop Elements have a few similarities. Both are 8 bit only at present. They can do full color management. They have layers and layer masks, as well as many strong image enhancement tools. They do lack the content aware clone feature of the full Photoshop. Either one is a great choice for anyone shooting only jpegs and not making prints: 16 bit is irrelevant in this case. They are still a reasonable choice for printing as long as the editing is not too extreme. These are also good choices for design and digital art, as they have many drawing tools.
As for their differences, first and foremost Gimp is free, although Elements is a good bargain at under $100. Elements includes Camera Raw for processing Raw files. Gimp needs a plug-in to do this. Gimp has 16-bit processing due out in the next version. It also has the path tool for drawing, and batch processing, which are absent in Elements. Elements can work with many popular plug-in programs. Gimp has many plugins available to extend its functions.
Lightroom
Lightroom is a program that integrates file management and processing. It creates a preview of the image, showing the results of processing, without a whole new image or larger layer file. This saves hard drive space and reduces the number of images in your catalog. It also allows virtual copies for alternate versions, again without a whole new image or large layered file. The price is in the mid $100 range, a good bargain considering all that it does. Lightroom has 16-bit processing for all files that support this. It has color management for exports only, you always work in the prophoto rgb space. You can integrate with photo editing programs and directly work with plug-ins to do more advanced processing.
Lightroom uses database management, which is slower but allows for more features. This is possibly confusing to those used to directly browsing the hard drive. The program is probably more complicated to learn because of all the functions. For a program that is a fast browser with ability to keyword, look at Photo Mechanic, although it is similar in price to Lightroom.
Picture Window Pro
Picture Window Pro is a program from a small company near Boston. It costs less than $100, and a more basic version is available for about $50. The program features 16 bit processing and full color management. It does not use the layer model of processing, each stage is in its own window and can be saved or combined with other stages. The program has many powerful masking tools for selective editing. It offers much of the advanced capability one might want from Photoshop. HDR can be done with a semi-automated system of masks. Panoramic stitching is quite possible, but entirely manual. Picture Window Pro does not take plugins, but can do manually what many of them do. It is specifically for photography; there are not many digital art features such as drawing tools.
PhotoLine
I have not tried this program yet. It has 16 bit processing, color management, and layers. There are times where I like the layer mask approach and I will check this out soon. A 30 day trial is available and it is under $100.
Plug-ins
These generally do not work by themselves, they must be called and used from within a host program such as Gimp, Elements, or Lightroom. They add other functions and extend some functions of the host program. The Nik suite is now available from Google and is a great buy in the mid $100 range. The various programs do HDR, black and white processing, noise reduction, and selective enhancements. The masking tools are powerful and easy to use.
I also use a couple of the Topaz plug-ins, Detail and Adjust, which provide a palette of artistic enhancements, and sharpening effects. I use them mostly as a different sharpening tool.
Auxiliary programs for specialized processing
Here I am considering mainly HDR, panoramic stitching, and focus-stacking. These are in Photoshop, and so if you don’t use Photoshop and want these capabilities you will need alternatives.
The 2 most well-known HDR programs are Photomatix and the Nik Plugin HDR Efex2. They both offer exposure blending into a hi-range 32 bit image and then tone-mapping of the image into a viewable version. Photomatix also does exposure blending, which is to combine the best-exposed portions of each image directly without a 32-bit intermediate or tone-mapping.
There are other lesser-known tools as well, some of them with free versions, the others under $100. These include SNS-HDR, FDRTools, Luminance HDR, TuFuse Pro, and PanoTools Assembler. If you dare to work on the Windows command line, there are Tufuse and Enfuse, both free. Most of these do exposure blending, some have tone-mapping as well.
Each of these tools has different approaches to blending and mapping exposures, so I consider this to be a suite of tools I can use to find the right one for any particular photo. I usually go to HDR Efex2 because it is easy to use from Lightroom, then go to Picture Window Pro and these others if I want a different result.
Focus-stacking is the combination of different frames of the same scene with overlapping areas of focus. Thus you can get an entire scene in focus even though your depth of field is small in each frame.
The well-known software for this is Helicon Focus. A newer choice that is gaining notoriety is Zerene Stacker. Both of these are in the upper $100 range. A lite version of Helicon is available, but it is also temporary and more money than some permanent licenses I have bought. I avoid these in favor of Pano Tools Assembler. I do bet that these might be less intimidating to use.
Panoramic stitching is the combination of individual exposures with overlaps into one large image. I use PanoTools Assembler, under $100. It uses tools that can be used for free at the command line, but the GUI controls are worth the price. Also well-worth the price is that this program can combine all 3 operations of panoramic, exposure, and focus blending of images. Perhaps you have several frames to stitch into a panorama, but each frame needs several exposures to capture the highlights and shadows well. And then perhaps some of those exposure sets also need to be focus-stacked for a sharp image front to back. Simply feed all of it to Pano Tools Assembler, hit “Auto-Create”, and it will sort all of this out for you. Do be prepared to take a break while it works, even on a fast computer.
Pano Tools Assembler will also just do exposure or focus-stacking separately. Again, the “Auto-Create” button usually does the trick. Hint: to do focus-stacking, hold down shift while hitting that magic button. The control panels of this program are quite intimidating, but also offer a high degree of customization if the auto option fails to give good results.
Conclusion
These tools provide a viable alternative to Photoshop in various combinations. You don’t need to get all of them to do strong image processing. Each has a permanent license that allows you to use the program for as long as you like. The upgrade prices are about half of the original purchase, and some of the smaller programs give free upgrades. You will not have to pay monthly for the ability to open and work on your images.