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Before I found out about Camera Raw, I used to convert my photos from RAW to TIFF, using the XNVIEW convertor, downloaded from the Internet.

My question is whether I lost image quality or anything else. It is obvious that the colors changed, but is this the only problem?

However, after finding out about Camera Raw, I downloaded it, but I didn't notice the ''open image'' button at first. For this reason, I saved the RAW file as a TIFF file and then opened it separately in Photoshop CS6. Did I lose any image quality by doing this?

Just to clarify: Did I lose any image quality, in terms of compression?

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    For my kind of RAW files (ORF) XnView is not a converter. It just reads the embedded processed JPEG. So in that set up it would have been pointless to shoot RAW in the first place, you would have lost every possible benefit of shooting RAW. – his Jun 30 '14 at 23:22
  • For earlier versions, sending an image to PS from LR just sent it a 16-bit TIFF. But later versions (not sure which side CS6 is on) is smarter, and current CC version will open as a smart object and let you re-adjust the raw conversion even after you do other work (in particular, compositing) – JDługosz Dec 28 '14 at 20:08
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The question here really resolves around what you mean by "quality", followed closely by needing to understand what RAW really is and how it relates to other image formats.

On the first TIFF is generally not compressed in a lossy way, so artifacts weren't introduced. By that measure, quality isn't degraded in the same way it might be with JPEG (and especially with re-saving JPEG or by using high JPEG compression levels). So, if detail loss from compression is all you are concerned about, no, there is no loss of that sort.

But, take a look at What is RAW, technically? and Good examples of RAW's advantages over JPEG?. What you loose is flexibility, since the initial conversion "bakes in" decisions about color balance, contrast curves, and demosaicing, and sharpening. Once those are saved into an image format like TIFF, you can make only a more limited range of adjustments, so in that sense, you have lost something.

Depending on the conversion choices you made, this could include loss of shadow or highlight detail, sharpening choices (too much or too little) that you regret later, white balance adjustments, contrast curves, and more.

That said, there are two things to keep in mind before panicking.

First, the range of adjustments you can make and still get excellent results even on JPEG files is still large, and this is particularly true if you're basically in the ballpark anyway. RAW conversion is not a substitute for getting the shot basically right in camera, and so conversely, getting it close to right in camera makes RAW conversion less important. Still, having the RAW files does give you more flexibility, particularly in color balance — the second link I give above demonstrates this nicely.

Second — and this is more of a philosophical point — you don't have to be obsessed with the idea of preserving all of your history in case you might want to go back and redo. You could do that, and it's a perfectly fine choice for some people. However, it's also perfectly valid to leave your finished work as it was, and to concentrate on improving for the future. For this, you might shoot RAW and your conversions, and if you're happy with them, only archive the TIFF or JPEG final output. Some might gasp: "but that's like throwing out the negatives!", which is partially true, but, also, not the end of the world. Only a certain subset of photography enthusiasts care about looking at negatives: everyone else wants to look at the final prints. (Or the digital equivalent.)

  • Thank you for answering, Matt! By saying quality, I meant that I am interested in finding out whether I lost image quality. The colors changed after the conversion, but this is not a problem for me, as I was not looking for real colors. My question is only based on whether I lost image quality, not colors. – Morpho Mar 31 '14 at 16:08
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    But what do you mean by "image quality"? Is color not part of that? If not, why not? – mattdm Mar 31 '14 at 16:53
  • I mean is there any compression? – Morpho Mar 31 '14 at 19:01
  • You say that decisions about contrast curves are baked in, but surely this is only true if the shadows and highlights are clipped. Assuming they aren't surely the image contrast curve maintains the full range of data? – Undistraction Apr 18 '16 at 15:57
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    @Pedr Mostly if shadows and highlights are clipped, but you also have rounding/truncation that can't be undone. Saving in 16 bits will mitigate that. – mattdm Apr 18 '16 at 16:37
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@matttdm answered rather about 'image quality' hence I will concentrate on the other part of your question: '(I lose) ...anything else'

Also, I will speak about XnView MP (the enhanced version of XnView) which is due to a new release shortly with big enhancements because is the program which I use heavily from several years now, after I upgraded from XnView.

Apply what I say to XnView - most of them should work, even if something not as powerful as in his newer and enhanced brother, XnView MP.

The main things which you'll lose are:

  • editing/post-processing power/latitude - mattdm detailed this, I will not talk about it again.

  • streamlined workflow - the TIFF step induces an unnecessary step which you must manage taking your attention away from what you must do.

  • speed - Obvious. The conversion takes time, even if XnView has (one of) the fastest conversion engines available. I tested a lot of conversion programs and only XnView MP surpasses it. Also, after the conversion is done, you must go in the 'other program' (Photoshop) to chose 'Open', to find your TIFF file...

  • in-place editing - If you're more-or-less satisfied with how you Raw looks like, and you want only 'normal' adjustments (levels, brightness, crop, sharpening etc.) why you don't just do a simple double-click and edit the image in XnView MP?

  • management power over your collection - by exporting them to TIFF you induce quasi-duplication of your files just for the sake of them. You need to take care of these files which will clutter your collection, fill up your storage etc.

Also, in the new XnView MP will be an all-new cataloging engine for which these intermediary TIFF files will be just noise. (of course IMHO)

The 'normal' (best) workflow with Raw files is by using XnView's 'Open With...' feature which allows with great flexibility to configure one or more programs to process your selected Raw file(s) - they will be transferred as full raw to the destination program. See the screenshot bellow (taken from XnView MP):

XnView MP External Programs Engine

  • Thank you, John! However, I am not interested in how XNVIEW works. I am satisfied with Camera Raw at the moment. I am interested in finding out if there is any compression from converting my RAW files into TIFF, using this specific program (XNVIEW). – Morpho Mar 31 '14 at 19:04
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    If you're interested that there is any compression, then you asked a wrong question. Also, ISTM that you're an absolute beginner (nothing wrong with that) and you must read enough about such things. Keeping it simple, by compressing files, if the compression is loseless, the quality will NOT decrease. For TIFF, LZW is a good loseless compression. – John Thomas Apr 1 '14 at 4:40
  • I'm not an absolute beginner. John! Nobody knows everything and this is not a site to prove this. I can accept that I may have not expressed myself well, because I am after all a foreigner. Thank you for answering me! Image quality involves the matter of compression. This is written in all photography books and websites. Also, my question was ''Did I lose image quality and anything else? It is obvious that colors changed...''. I read thousands of info about image formats and I know well about them. TIFF is lossless, I know, but I would like to be sure about the XNVIEW program. Thanks! – Morpho Apr 1 '14 at 10:01
  • tomjewett.com/photography/IQintro.html - ''Image quality is dependent on five basic factors: The first two are completely dependent on the camera: sensor, lens. The second two are shared by the camera and the photographer: focus, exposure. The last is a camera capability selected by the photographer: recording format - RAW, TIFF, JPEG (compressed or uncompressed files, processed or not etc)." So compression is involved in the matter of image quality. – Morpho Apr 1 '14 at 10:51
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If you saved your TIFFs with 16bit per color channel, you didn't loose any quality. If you saved them with only 8bit, then yes, you lost color resolution, just as with a high quality JPEG. (the TIFF is losslessly compressed, so you don't loose anything by that, but a JPEG with maximum quality isn't noticeably degraded either).

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    Even a 16-bit TIFF "bakes in" WB, contrast, black point, white point, etc. Not to the same degree that an 8-bit raster image format would, but you lose much of the flexibility of the raw file. – Michael C Aug 22 '18 at 20:33
  • there's a lot of mysticism around raw files. as long as there is no clipping, all the data is still there in the tiff. – ths Aug 22 '18 at 21:02
  • Not if the black point has been raised above '0' or the white point has been lowered below '16,383' – Michael C Aug 22 '18 at 21:04
  • why? when you don't have any values exceeding that (clipping) that should be fully reversible. – ths Aug 22 '18 at 21:05
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    TIFF is a raster image format. If we're talking about RGB TIFFs then there are some things "baked in" that are irreversible in the sense that the TIFF can not be "deconstructed" to produce the exact same data as was contained in the source file. When color channel multipliers are applied to produce the TIFF, there is rounding that must go on. Rounding is irreversible. It is possible to produce a TIFF without applying color channel multipliers, but that is not what most people mean when they say they have converted a "RAW" (sic) to a "TIFF." – Michael C Aug 22 '18 at 21:08
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Actually, the image information in RAW files is in TIFF.

To quote from the Wikipedia article on RAW:

Many raw file formats, including IIQ (Phase One), 3FR (Hasselblad), DCR, K25, KDC (Kodak), CR2 (Canon), ERF (Epson), MEF (Mamiya), MOS (Leaf), NEF (Nikon), ORF (Olympus), PEF (Pentax), RW2 (Panasonic) and ARW, SRF, SR2 (Sony), are based on the TIFF file format.[4] These files may deviate from the TIFF standard in a number of ways, including the use of a non-standard file header, the inclusion of additional image tags and the encryption of some of the tagged data.

Essentially, a RAW file is TIFF image data with added (sometimes proprietary) metadata. The ISO TIFF/EP standard is a standard way to add metadata to TIFF, but most manufacturers use EXIF instead for that task.

So, no, saving the file to TIFF--assuming the conversion knows how to unwrap your RAW file headers and metadata from the image data properly, and you're matching the bit depth and don't add lossy compression (which TIFF can do, although rarely), won't affect the image quality--but it will probably lose metadata, such as your white balance setting. If you haven't processed the RAW first, you aren't "baking in" a white balance setting, you're simply losing it.

  • This is technically true but I don't think is the point of the question — I don't know of any software which converts to something it calls TIFF which actually keeps the RAW data in its unconverted form. – mattdm Dec 28 '14 at 0:55
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    You are forgetting the Bayer mosaic. Converting, even if you save 16-bit samples, will commit to the de-mosaicing process you used for that. Does settings such as color correction, exposure, and sharpening interact with the de-mosaicing rather than simply applying to a converted form? It did in Bibble; not sure if LR does that. The resulting TIFF will be many times the size, so what's the point? – JDługosz Dec 28 '14 at 19:59

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