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I shoot Fujifilm and like the builtin film sims. Capture One, does a good job at reproducing them, but I find sometimes Fuji JPEGs better, particularly when some proprietary features (e.g Color Chrome FX) or alternative film simulation recipes are used, since they cannot be reproduced as is in a photo editor like C1 (only X Raw Studio can help somewhat).

Some folks do light basic editing (crop, perspective & lens correction, ...) of the jpegs but the operation is lossy, since every time you do something on the jpeg file, you lose some image quality.

I do sometimes convert the JPEGs to PNG and edit the latters in C1, considering that once converted in PNG, you kinda "freeze" (in theory) the image quality of the original JPEG, until you do a final conversion to JPEG.

I didn't find information about such a workflow (JPEG > PNG > Edit > PNG).

So questions are:

  • Does it make any sense and offer the possibility of some limited of the JPEG file editing without loss of quality ?
  • Does editing of a JPEG file in Capture One preserve its original image quality ?
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    \$\begingroup\$ @RomeoNinov You can have more than 8 bits per channel with PNG! \$\endgroup\$
    – U. Windl
    Aug 29, 2023 at 6:31
  • \$\begingroup\$ I think any workflow editing images that were the result of previous edits is broken. That's why people hype on "non-destructive" editing (like in Adobe's Lightroom). As a side effect you can undo any previous edits without any loss of quality. \$\endgroup\$
    – U. Windl
    Aug 29, 2023 at 6:39
  • \$\begingroup\$ First, color Chrome FX is no nostalgia and second, you can consider the use of a film simulation as an in camera preset (instead of editor). Both are an artistic choice and can give a specific mood to the picture. Point was to kinda get the best of both worlds with further editing (dodging & burning, etc.) \$\endgroup\$
    – fmplayer
    Aug 29, 2023 at 8:01
  • \$\begingroup\$ @U.Windl yes you can, but 16-bit PNGs compress much worsely than 8-bit ones. You could just as well use uncompressed (for faster loading and saving) TIFF then. \$\endgroup\$
    – Ruslan
    Aug 29, 2023 at 21:07
  • \$\begingroup\$ @Ruslan Probably because of the entropy: For 8-bits resolution you'll have more similar pixels than you'll have with 16-bit resolution. It has nothing to do with compression or bit resolution per se, but if you preserve more details, the result will be larger. \$\endgroup\$
    – U. Windl
    Aug 30, 2023 at 6:20

4 Answers 4

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I think your understanding is incorrect. Converting a JPEG to PNG doesn't magically aid in quality preservation as you edit an image. Essentially, when an image is opened in an editor, the filetype that the image had been stored as is irrelevant; you are simply dealing with pixels that each have a RGB value. (These are 8-bit values in the case of JPEG.) When you push these pixel values around (i.e. applying edits to the image), new RGB values are calculated for the pixels. It doesn't matter if the image was a camera-original JPEG file or a PNG file saved from that original, the RGB values are going to be the same.

The difference comes when the image is re-saved as JPEG. It's at that moment that lossy compression is applied for JPEG files, and that's where quality is theoretically lost. If you were to save as PNG or TIFF, no lossy compression is applied. (Personally I prefer TIFF – probably things have changed, but there was a time when PNG didn't support colour profiles.) Re-opening these 2 hypothetical JPEG / PNG files can result in different RGB values for some pixels. This loss in quality however, based on re-saving a high-quality JPEG file as a high-quality JPEG file, one time, is negligible. You won't notice it. Still, if you intend to apply further edits, it makes sense to save your file using an image format that doesn't apply lossy compression.

The big difference is between 8-bit and 16-bit files. When you push pixel values around in a 16-bit file (i.e. applying edits to the image), then new RGB values are calculated with more precision, and there's more "room" for gradation between colour values. Especially for editing, 16-bit images are more, let's say, "desirable" than 8-bit images.

This explanation is a simplification, but hopefully adds something.

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  • \$\begingroup\$ Yes it does add! Thank you. I understand that an acceptable workflow could be: get the JPEG either SOOC or from X Raw Studio, import it in C1, do the edits, than save it as PNG. ... but work the RAW file in case of tricky pictures \$\endgroup\$
    – fmplayer
    Aug 29, 2023 at 8:20
  • \$\begingroup\$ Saving a TIFF in e.g. Photoshop does allow jpeg compression as an option (none, LZW, Zip, and jpeg), obviously using this compression option causes the same quality-loss issue you mention. One problem with 16-bpp is that exporting/converting to 8bpp for general use and distribution introduces dithering and quantization. Usually imperceptible but can be seen in e.g. gradients. \$\endgroup\$
    – Yorik
    Aug 30, 2023 at 18:22
  • \$\begingroup\$ @osullic Your first paragraph would not be correct if applied to raw files. When one applies adjustments to raw files the pixels showing on the screen are not modified, the actual raw data (which is not even remotely what is visible on the screen) is reconverted using the new instruction set. \$\endgroup\$
    – Michael C
    Sep 1, 2023 at 2:42
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If you want manufacturer-quality editing, filters/LUTs etc, use the manufacturer's software.

If you want to edit further after that, use 16-bit TIFF.

Only ever go to 8-bit at final export.

Yes, this makes for some heavy file sizes, but HDs are cheap these days.

A bit breif for an answer, but didn't want to post as a comment …and didn't really have much else to add;)

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  • \$\begingroup\$ With current display technology (I'm talking about maximum contrast) exporting to 8 bits eventually is obsolete IMHO. To avoid color banding, you probably want 10 bits at least. \$\endgroup\$
    – U. Windl
    Aug 29, 2023 at 6:34
  • \$\begingroup\$ Never saw any banding in SOOC JPEG files. I guess it's the result of further JPEG processing. \$\endgroup\$
    – fmplayer
    Aug 29, 2023 at 8:04
  • \$\begingroup\$ @fmplayer yes you can see banding at 8 bits per channel, U. Windl is right. Someone once gave me a sample that shows it well, and I made a computer generated copy just to convince myself that it wasn't artifacting. SOOC can mask the effect if there's any noise in the image at all, noise breaks up the edges that make it easy to see. \$\endgroup\$ Aug 30, 2023 at 2:51
  • \$\begingroup\$ @U.Windl it's possible to go from 16 bits to 8 without visible banding, if you use dithering. The problem is that nobody does that, and it isn't effective with JPEGs. \$\endgroup\$ Aug 30, 2023 at 2:55
  • \$\begingroup\$ @fmplayer Any SOOC JPEG depends on how the camera's JPEG conversion engine is processing the raw data. So each camera, with each possible combination of in-camera settings that affect raw-to-JPEG conversion, can depict the same scene differently. Some cameras do much better than other cameras with scenes that might be prone to banding, and some combinations of settings will do better than others for the same camera. \$\endgroup\$
    – Michael C
    Sep 1, 2023 at 2:47
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Not sure if you considered it but each major camera manufacturer has their own raw file developing software which should produce same image as in-camera JPEG (you might check it yourself using raw+JPEG pairs of images produced by camera). For sure Fujifilm has it too and it provides a lot of output options. It's named X-RAW Studio in your case.

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  • \$\begingroup\$ I mentioned XRS in the question. Problem is that it does not allow some editing features like layers, which is useful for dodging and burning \$\endgroup\$
    – fmplayer
    Aug 29, 2023 at 8:11
  • \$\begingroup\$ @fmplayer can it export anything more than JPEG? \$\endgroup\$ Aug 29, 2023 at 10:05
  • \$\begingroup\$ It depends on the camera. Some, like GFXes or XT4 can for sure. Check recent Xpro series and recent expensive cameras like xt5 and xh2 \$\endgroup\$
    – fmplayer
    Sep 2, 2023 at 7:54
  • \$\begingroup\$ @fmplayer I was rather asking about XRS. Exporting hit bit depth image from camera would be waste of space if XRS can do it and the image quality might be better from XRS too. \$\endgroup\$ Sep 2, 2023 at 8:20
  • \$\begingroup\$ XRS works with the camera's processor, not the computer's. Hence only parameters accessible to the camera can be tweaked (which is plenty btw). Image quality is that of the camera, no less no more, same for output format. \$\endgroup\$
    – fmplayer
    Sep 2, 2023 at 14:09
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To add to the other answers; if you want your edits to be "lossless" you should convert the file to a 16bit tiff and edit it in C1 using layers and layer masks; keeping the original file/base layer unedited.

That way all edits can be reverted without loss of the original data. Save the the working file tiff with lossless compression with all layers.

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  • \$\begingroup\$ No need to overkill with TIFF. JPEG and PNG files can also be added layers in C1. C1 considers a JPEG file like a RAW in that matter. \$\endgroup\$
    – fmplayer
    Aug 29, 2023 at 8:09
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    \$\begingroup\$ @fmplayer, but only a tiff can be saved keeping the layers intact. \$\endgroup\$ Aug 29, 2023 at 12:57
  • \$\begingroup\$ Even a 16-bit TIFF does not preserve all of the information in most raw files. White point and black point are baked in with conversion to TIFF. WB is, to a lesser degree, also baked in. 16-bit gives more latitude than 8-bit color does, but the monochromatic luminance values contained in most raw files are not preserved at all in a 48-bit (16-bits per color channel) TIFF. \$\endgroup\$
    – Michael C
    Aug 31, 2023 at 19:26
  • \$\begingroup\$ @Steve Kersting Once a file, be it RAW or JPEG or whatever has been imported in C1, both the original file and the layers are preserved by C1 \$\endgroup\$
    – fmplayer
    Sep 2, 2023 at 7:50

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