Nikon, Gimp, Jpeg: Quality of Jpeg and the value of Raw files Comments perhaps especially for fashion photographers {Conclusion: Jpeg has a lot of art in it, when done EXACTLY right.} How good is Jpg quality 100 in Gimp? Quality percent 100 corresponds approximately to what Nikon calls 'Fine' Jpg when Jpeg Compression is set to 'Optimal Quality'. Note that on Nikon Df one must be sure to enable both these two settings to get the full 100 percent jpg, and I imagine much the same applies for other advanced cameras. Let us be aware that the Quality Percentage setting in Gimp is to some extent a later development in the history of Jpg. There are many conversion packages for Jpg from the 1990s AND LATER that blur and mess up Jpg's even after a single cycle of load and save EVEN WHEN the quality settings are at the highest. The open source package Gimp, available at many platforms, incorporates a quality setting that actually works. I myself use quality setting 90 for publishing anything online and 100 when storing internally for later change (and anything in between for images that may be changed but it doesn't matter if the image gets slightly affected by it). The following source .jpg image had the text patched onto it in Gimp, if you enlarge the image very much indeed you can study the area around the text. It will have changed the most when the image has been loaded, then saved at Gimp Quality Percent for Jpg at 60, then loaded and saved again at same percent, then loaded and saved once more at same percent. As you see this in a browser, CLOSELY STUDY THE AREA AROUND THE LETTERS WHEN THE BROWSER IS AT MAXIMUM ZOOM, and there will be very noticable change when quality setting is at 60, for the third cycle of load and save. 90 turned out to be much better at this than what I thought it would be--it seems to perform very nearly as well as 100. At Jpg Quality percent 90, it is hard to find any changes even at the third cycle, unless you know exactly where in the image to look. At Jpg Quality percent 100, it does not seem that there are any changes--even after three cycles of loading, saving, loading the saved, saving that one and loading it again--although it's not impossible that there are some changes. source.jpg qualitypc_60_cycle_1.jpg qualitypc_60_cycle_2.jpg qualitypc_60_cycle_3.jpg qualitypc_90_cycle_1.jpg qualitypc_90_cycle_2.jpg qualitypc_90_cycle_3.jpg qualitypc_100_cycle_1.jpg qualitypc_100_cycle_2.jpg qualitypc_100_cycle_3.jpg Finally, here are some contrast/brightness, color balance and such changes done, successively, with the qualitypc_100_cycle_3.jpg in Gimp, very fast--just to show how elegantly Gimp handles Jpg's: qualitypc_100_cycle_3_modification_1.jpg qualitypc_100_cycle_3_modification_2.jpg qualitypc_100_cycle_3_modification_3.jpg qualitypc_100_cycle_3_modification_4.jpg The original image is, with acknowledgements, at instagram.com/berlinib in September 2018. NEXT: Some comments on NEF (Raw) Format versus what Nikon calls 'Jpg Fine' with added option of No File Size Compression, also called 'Optimal Quality' with insights deriving also from PhotographyLife.com/N. Mansurov {the latter of whom has the copyrights to the images used in the experiment, next} There are many texts discussing Raw versus Tiff and Raw or Tiff versus Jpeg. Some opinions may be based on repeated assertions that has to do with the history of Jpeg. The 'raw' facts, so to speak, are these: * Raw provides, on Nikon, 12 or 14 bits color depth, whereas the typical classical Nikon-camera-generated Tiff provides less color depth and Jpeg also provides less color depth. That accounts for the MAIN differences in lack of what one can do with the image afterwards. The Raw image format is technically nothing but a Tiff with expanded color bit depth and where, in contrast to Tiff, there are additional storage of the settings of the camera. * Some settings, such as ISO, are calculated by the camera processor when stored in Tiff or Jpeg but not calcualted when stored in Raw. So for SOME settings, one can do better with a full PC CPU afterwards and a powerful program; the algorithms at the PC may be better in some cases perhaps. * Given NO size compression in Jpeg and Fine Quality, or what Gimp calls 100 percent Jpeg quality, Jpeg is MORE OR LESS lossless -- not just Tiff and Raw. * When it comes to possibility of recovery of colors in Jpeg when an image was stored straight in Jpeg, I did my own experiment on the photos shown in the very informative and learned article at https://photographylife.com/raw-vs-jpeg and after showing his examples I show the result of Gimp recovering fairly much the colors in the Jpeg image by patient use of its 'Curves' option: His examples {copyright PhotographyLife.com/N. Mansurov}, click on them: To the left, his Raw-based image; to the right, his Jpeg-based image And here is my example, using the image on the Right, patiently adjusting via 'Curves' in Gimp to approach the result of his Raw-based image: So, while the technical arguments in favour of Raw are correct in an absolute sense, it is to be an open question whether they are correct in a practical sense. Consider this quote from the article above: "As you can see, the image on the left contains a lot more color and detail than the one on the right. The change in colors is especially noticeable in shadow areas and this is all due to the fact that the JPEG file is an 8-bit image and contains much less information for full color." A more correct statement is that it is not "all due" to it, but rather than "something of it is due" to it. So: It may be that what is sometimes attributed to 'mere' 8-bit color depth--which is, for RGB, 256x256x256 or a neat 16,777,216 colors--is PARTLY a result result of how one uses what image modification program, and PARTLY a result of image depth and how the camera CPU calculates the transition from Raw to Jpeg or Tiff. But just how much one aspect weighs in isn't decided from just some examples and certainly cannot be grounded on arguments about Jpeg that stems from the history of how Jpeg image editors evolved. Personally, I'm very impressed with these features: * The way that the 12/14-bit color depth of Nikon Df is calculated into the 8-bit JPG by the Nikon CPU * The quality resulting from, in Nikon Df, the Jpeg setting called 'Fine' when COMBINED with the Jpeg size setting called 'Optimal Quality', bringing about a practically lossless Jpeg {cfr the discussion above for Gimp} * The sheer quantity of pixels in the Nikon DF full- size image--this means that when, in general, as is typical, you want an image with considerably fewer pixels, the abundance of pixels creates a safer foundation for later changes of the images * And, as said, I'm impressed both with how Gimp can adjust images and in how lossless its one hundred percent Jpeg type is. As experts have pointed out to me, there is at least in principle more to gather from a Raw image than a Jpeg image and so why not save both? Technically, the advise is perfectly sound. And nobody should let image editor application stand in the way of choosing the right format--rather one should learn the right program tool, AFTER the format has been chosen. Is there a single artistic reason for choosing Jpeg over Raw image? In some cases, where few photographs are possible, and where few adjustments of light are possible, perhaps there are no artistic reasons: the art then consists in getting the most out of each click on the camera shooting button. (Video is a different discussion; put simply, I think photography --ie, making photographs--is a higher art than that of making bundles of 25-images-or-more-pr-second in the illusion of movement we call 'video'.) But when, in model photography, you are having a kind of dance of camera, of models, of light, and of yourself as photographer, all intermingled with the generation of hundreds of photos each hour--from which a slight fraction is going to be used--then you can use what may be your intimate contact with the internal aspects of the Jpeg format in a way that communicates directly to, and from, your gut feeling--BECAUSE, and NOT IN SPITE OF, the fact that such as white balance is already calculated into the image. Your internal preview of how it is going will then lead you, as an artist in movement, to modify the scene to give you that which no program can emulate in after-modifications. Put simply: gut feeling, intuition, instinct, tacit knowledge, photo-shooting-from-the-hip--these things needs feedback and some simplicity in that feedback. If you save, by each click, a multiplicity of images, you get confused feedback. Art consists in playing at limitations, not seeking the limitless. My vote--with all respect for the disciples of Raw and their rocket science capabilities of modifying images-- goes for the time being to one hundred percent jpegs. Jpeg has a lot of art in it, when done EXACTLY right. Aristo Tacoma September 2018