DxO Labs is one step ahead of GIMP, in theory at least, because it has built the very same Film Emulation product into it's super fantastic Raw Data file converter - Optics Pro Ver.9. This means that you can select your film emulation within the Raw File conversion process, which should be much better than either of FilmPack or GIMP's new capabilities, which relies on having a JPEG file already converted, as it will not work with Raw Data. But is it really better? I'll let you decide as best as you can from several conversions I made of this one rather bad picture (I want you to look at the image quality over and above my own so-called artistry). The very first one is or reference - it is a DxO Raw File conversion based solely on my camera body, not FilmPack. As such, it may be the best looking one of the bunch. But the real idea here is to compare how well GIMP's execution of Film Emulation works on an already converted 8-bit JPEG, up against DxO Lab's more direct application of Film Emulation to the Raw File itself.
|RAW, Direct Conversion With DxO Optics Pro, Generic - this is the Reference JPEG|
|RAW, Direct Conversion With DxO Optics Pro, Agfa Vista 200|
|Reference JPEG, GMIC-GIMP Agfa Vista 200|
|RAW, Direct Conversion With DxO Optics Pro, Fuji Superia 200|
|Reference JPEG, GMIC-GIMP Fuji Superia 200|
|RAW, Direct Conversion With DxO Optics Pro, Kodachrome-64|
|Reference JPEG, GMIC GIMP Kodachrome 64|
|RAW, Direct Conversion With DxO Optics Pro, Kodak Ektachrome 100|
|Reference JPEG, GMIC-GIMP Kodak Ektachrome 100|
|RAW, Direct Conversion With DxO Optics Pro, Kodak T-Max 100|
|Reference JPEG, GMIC-GIMP Kodak T-Max 100|
|RAW, Direct Conversion With DxO Optics Pro, Rollei Ortho 25|
|Reference JPEG, GMIC-GIMP, Rollei Ortho 25|
To my eyes, the similarities are remarkable. The same challenge of Film Emulation is executed here within two totally different products - one you pay a lot for, the other one is free, yet, the overall look of the simulated film types is remarkably similar. This means that both teams really did their homework. I was actually skeptical enough about film emulation that I was expecting to see highly visible differences between the two.
As for which does the job better, I would have to say, as expected, the DxO optics Pro with FilmPack Plug-in has better contrast, texture, and color vibrancy, but not by much. In the B&W examples, I can see almost no difference, and for Agfa Vista 200, I think GIMP actually looks more appealing. There are many other films to choose from in both products, as well as the ability to tweak the end result with both.
One thing to really keep in mind - GIMP is free, and DxO Optics Pro will set you back the price of a new compact digital camera! Also, of you're not into shooting Raw Files - like, if your camera won't do it, or if you're like Ken Rockwell and don't see the point, it's a no-brainer - this wonderful new G'MIC-GIMP Plug-in is free, and it works in Linux (also Windows and Mac). DxO Labs does not sell products that work with Linux.