Big is a bit of an understatement but some packages such as After Shot Pro use them in a slightly different way that impacts on how they are used.
Not really correct. The important aspect is that the raw converter needs to be able to handle the raw files bit depth. Neglecting 10 bit visual images the object of the exercise is to get the bit depth recorded by the camera which can actually be less than it's capabilities into 8bit according to the intended result. This may take a little more skill than retaining the whole data throughout PP. When worked on 8bit it is advantageous to have a workspace holding this at a greater bit depth. It wouldn't surprise me if Elements uses 15bit as that is what Adobe started off using.Second, working with 16 bits per channel is a big deal when cameras support 14 bits of real data acquisition. Many third party apps (and PhotoShop Elements the last I knew) do not support more than 8 bits per channel. This is a real deal-breaker with many applications to my mind.
As Manfred mentioned Nikon's raw processing software has not been reverse engineered. Another way of putting it is that it's different. It for instance some how or the other produces a unique camera profile for every shot taken. It's also possible to store curves in some of the camera although I have never bottomed out which ones. Once again these curves are different because they are not camera profiles. They basically alter the tonal response of the camera and colouration. An application called Ufraw allows these curves to be applied to shots from any camera. On the other hand a number of people on here produce good shots using Adobe camera profiles which follow the normal way of handling this area.Third, the raw converters (assuming the program even has one) vary tremendously between products. The PaintShopPro raw converter is not awful, but it isn't as good as Adobe's. I always use the Nikon program for raw conversion because it is better than any third party converter, with full support for Nikon cameras and no reverse engineering. They add new cameras more quickly than any other program, too. But, if you want to use the built-in raw support of your image processig application, this is a big variable between applications.
GIMP is both ahead and behind PS but is more intended for people who are willing to get to grips with the basics provided by many bells and whistles and plugins in other packages. It also has myriads of plugins available. So many it is difficult to know what is of real use until they are found. In terms of what layer work often means there is little difference between it and PS. It's also possible to write plugins for Aftershot Pro. Coral will provide the information that is needed. People do.Finally, if you are a software engineer and like to develop your own image processing applications, GIMP is the clear winner over any of the applications, with a fully-documented interface and a large developer community willing to help you.
One odd aspect about the GIMP is that over the years there have been some purely photographic spin offs. They always fall by the wayside probably because GIMP development carries on without any tie ups with who ever is working on the photo version so they become incompatible. It also doesn't do a number of things which it could which would help casual users. This is largely because many people who work on open source software are doing it because they want some particular feature themselves. They are also likely to be very proficient at using it. Developers come and go. People are inclined to think that there is a solid core of people working on it. Unfortunately there isn't on lots of open source software.
Not true at all. 32 bit applications use memory management AKA paging to extend memory indefinitely. The overheads for doing this are from what I hear are rather low. What can be more of a problem is operating systems placing an artificial limit on the amount of memory that they will make use of. Windows have done this in the past in order to get people to pay for more expensive options really. One release was famous for this as people fitted more memory without realising that it wouldn't be made use of. The motherboard may also limit it and often does at some point - usually so high that most people need not worry about it.ETA: 64-bit applications are important any more, too. Many of the third-party apps are still 32-bit. Given that each image may run 100 MB or more now, you need a lot of address space for working with some operations (panoramas come to mind.)
John
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