How Does Lossless Compression in Fuji Raf Files Work? (2020)
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Lossless CompressionRaw Image FilesFujifilm Raf
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Lossless Compression
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Fujifilm Raf
The post explains how lossless compression in Fuji RAF files works, sparking discussion among photographers and tech enthusiasts about the benefits and potential performance issues of compressed RAW files.
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The photo guys need to start taping magic rocks to their cameras to really keep up though.
Biggest problem with good raw compression is you have a linear DNG, half processed essentially. Great, the file size is smaller, but now you miss data that processes like AI denoise can benefit from as the image is already debayered.
On the flip side, good compression like DNG 1.7 spec's jpeg-xl compression is borderline magic. Lossless is actually lossless. The lossy flavour is so good even at 105 megapixels in 16 bit (per color channel) I would challenge anyone to spot a noticeable difference compared to the original, a file possibly 20x it's size.
On a tangent, bits per channel is yet another part people split hairs over. 14 vs 16 has almost no difference, no the colours are not 'better' even in a full 16 bit workflow, the only real world perceivable difference is your darkest darks are more precise and under extreme editing conditions do look a little better if being raised extensibly in post. I digress 16 is bigger than 14 and yay marketing.
Looping back to compression, 14 bit raws without compression are padded to 16 bit lengths due to word sizes and file constraints. This bit throws off the less technically minded who make all sorts of assumptions about file sizes and being 'more lightweight to edit'.
If you shoot a few thousand photos and then find you can't fix exposure as well as you'd hoped and the whole batch is worse, it's a pretty big disappointment, so it's smart to be risk adverse and skeptical.
IMHO marketing is almost always (part of) the problem. They shouldn't drink or smoke that stuff …
Equating "lossless" with "visually lossless" or some other phrase is newspeak. We could call a JPEG of quality >= 95 (or 96 .. 99) visually lossless too then.
Losslessness is easy to define: compress something, then uncompress it again and both the original and the uncompressed file should compute to the same (cryptographic) checksum.
https://www.whathifi.com/news/sony-claims-high-end-sd-card-o...
https://web.archive.org/web/20150220012844/http://www.machin...
[0] https://www.sony.co.uk/electronics/support/articles/00257081
Gotta hate companies these days with their dishonesty. "Lossless" means "lossy". "Unlimited" means "limited to 50GB".
Similarly (without starting an audiophile thread): Recording a vinyl record and compressing to a MP3 is "perceptually lossless" but will be different to compressing to a FLAC, never mind that the sampling output will always have random noise.
There are situations where they may decrease the bit depth of the final image if there’s not enough dynamic range, there are situations where even though the file is “uncompressed” the camera already does noise reduction and essentially compresses detail in the image, and so on…
[1] https://github.com/ImageMagick/ImageMagick/issues/6344
https://helpx.adobe.com/camera-raw/digital-negative.html#dng
You cannot preview or process lossless compressed Fuji RAWs on iOS natively but the uncompressed files are equal to Apple's own RAWs in support. On the field, it is sadly worth every byte to be able to grab a file directly off the camera and tweak it or send it to an editor. :/
Nitro¹ (macOS, xOS), the spiritual successor to Aperture², does support Fuji compressed RAW: https://www.gentlemencoders.com/extended-raw/
(I left Lightroom for Nitro + Apple Photos a couple years ago, and can strongly recommend Nitro to fellow photo takers.)
¹ https://www.gentlemencoders.com/nitro-for-macos/ ² https://www.gentlemencoders.com/about/
The Fuji X-T4 and X-S20 here produce images of 6240x4160 pixels, but I almost never look at images in 1:1. My 4K monitors, mostly set to 2K, display 2560 x 1440 pixels. And even when switch them to their full 4K resolution I don't view my images in 1:1 obviously. And the tablet l'm typing this comment on offers "meager" 1800 × 2880 pixels. Most family members look at images on their "smart" devices nowadays, where 2K or 4K aren't present. So even decompressed images are fine for them.
I have my cameras configured to take both JPEG (fine) + RAW (lossless) of course. Fuji JPEGs (and Canon ... etc too) are fine for most casual viewers. And if I want to crop certain parts, or adjust certain details (esp exposure), I have my RAW images as a fallback.
Storage? My SD cards are 256GB and my disks are definitely not a problem either.
You don't have to go very far before you've cropped a 20 MP source image into a 4K or 2K image, and if that part of the image that you've wanted to highlight is not well-lit, well, exposure is logarithmic and I want all of that RAW color depth that the camera can find if I'm going to turn black or white into perceptually accurate colors.
It's true that when my framing and exposure are great out of the box, I probably wouldn't notice or care if JPEG compression cut my file size by a factor of 4...but that's not always the case.
macOS, but my understanding of Retina is that even if your effective resolution is lower (e.g., my 6K ProDisplay has a resolution of 3008x1692), applications can designate regions to be "original resolution," so I'm getting the image's original resolution in the editing window or region.
Besides, it's still near impossible to get an X100 VI. B&H's backlog must be over a year at this point.
https://www.mpb.com/en-uk/product/fujifilm-x-t5
Or, as I have done myself and would recommend:
https://www.mpb.com/en-uk/product/fujifilm-x-t50
(Smaller, lighter)
The "new release premium" is just too high, in my opinion. Cameras aren't getting better so fast that you aren't better off with the previous model.
I still use X-T2, and it has not really aged, even when compared to my X100V. Infamous Fuji AF is where they progress slowly but steadily, so that's the primary feature that I'd look into when choosing between generations.
The question is whether you actually need such a camera for anything. With a new smartphone that has multiple lenses, out-of-the-box photos will turn out MUCH NICER than from a camera, because initial processing is built into the software. Digital cameras don't have this. You need to take RAW and work pretty hard on it to make the photo look as good as what a smartphone delivers right away.
In tourist destinations, you can often find middle-aged guys running around with huge cameras when in reality most of their photos are quite poor. Because they don't realize that with a regular phone, their pictures would be much nicer.
You’re completely neglecting to highlight Fuji’s film simulations. I use Fuji’s specifically because they produce excellent jpgs out of camera. Not really sure where your take is coming from, an xt3 on auto will blow any smartphone picture FAR out of the water.
There's NOTHING special about these profiles. It's a matter of taste. If you're buying a mirrorless camera, it means you have ambitions to take photos at a reasonably high level. Nobody who wants to be at a high level will shoot JPGs.
These are all pros and cons depending on the scenario, but a phone has one advantage - it's small and you have it always with you.
For quick shots to remember an event or night out, modern phone cameras are fine.
For anything that I’d call photography and actually want to print, display, etc. I rarely if ever get results I’m really happy with from a phone camera.
If you’re in any way interested in photography beyond taking a few snaps at parties and on holidays, I highly recommend getting a real camera. I’ve found the Fuji system to be great, from the lenses to the out of camera JPEGs and film simulations that mean you can pretty much avoid doing any significant editing or post-processing if, like me, you find that all quite tedious.
Fuji then has the whole film simulation system with all their colour science from the last century. It’s a ton of fun, and the jpgs it produces are distinct and beautiful, and I believe better than 99% of people could achieve from post processing the raws, myself included.
The middle-age guy part is accurate though, I got it as a thirtieth present.
I have the X-T4 and X-E3, both of which purchased used for much below the price of the newest models (about $800 each). No regrets, and I love both equally.
The E3 is my stripped-down pocketable camera; with the Fuji 27mm pancake lens, I can fit it in a jacket pocket or shoulder strap bag, and it weighs almost nothing, less than my iPhone. This combo is pretty much equivalent to the immensely popular X100IV, but much better value for money.
The T4 is the bigger camera I use for nature and macro shooting. Tons of settings, more advanced features (focus bracketing and "picture in picture" focus closeup are important to me), more advanced dials. It's heavier and bulkier, but also more solid (IBIS, weather sealing).
For some reason Fuji appears to consider yellow focus peaking (which IMHO is the best colourbfor it) to be a high-end feature reserved for the T4, which is annoying.
The X100IV is awesome, of course, and if I could afford it, I'd probably own one. But it's more than 2x what I paid for my X-E3.
A fixed-lens camera is built around the limitation of having just that lens. To me, if I only bring the 27mm with me when shooting, then that is exactly like a fixed-lens camera. But it also means I have the option to take it on a bird-watching trip using my Fujifilm 70-300mm lens — something you just wouldn't be able to do with an X100. That flexibility is worth something, which in my opinion makes the lower price of the X-E range even more of a bargain compared to the X100.
Definitely agree with you, I think if Fuji made the X-E range contain an ND filter, then it would be the ultimate every day camera. Whilst the 27mm F2 on the X100IV is nice, being able to go to an even lower aperture can be priceless in some situations.
The biggest annoyance I've found is the horrendous battery life on the X-T3. For a long day outside on a trip, I end up going through at least 3 batteries.
The XT-4 is identical to the X-T3 (well, more so than any other x-tn -> x-t(n+1) camera) but fixes a few of the flaws in the X-T3 with massively improved battery life + IBIS which I'd recommend just because a lot of acclaimed lenses these days forgo OIS (ref: many Sigmas for instance), which could be worth it over the long term.
If you are very price sensitive then the X-T3 is still a really good purchase, with nifty features like dual SD slots which make it great to have backups/RAW+JPEG on two cards. Compared to an average photo from a phone, there just isn't much computationally going on in mirrorless cameras so even an x-t1 would be a good purchase.
If you want to shoot photos for the experience rather than getting clinically perfect images, and do not want absolute performance wrt focusing etc., it's definitely at the top IMO; analog with every control having a dedicated physical control (ISO, Shutter Speed and Exposure Compensation and aperture on Fuji lenses). I love it because it's the equivalent of driving an air-cooled Porsche, warts and all.
I will say the only thing that gives me FOMO is the lack of the Classic Negative film sim, as a lot of recipes that I see online that I really like uses that film sim as the base.
If what appeals to you about Fuji's are the recipes and film sims, I'd make sure to research which ones you like, and then work out which model has the film sim you need to recreate it.
Yes, this is a very good camera. I love UI of Fujifilm cameras; and by that I do not mean the menu system (which is... serviceable) but the physical dial for each of the main setting. Putting them in "A" for automatic just make sense compared to the usual PSAM modes.
I never heard the fans on my M1 mac until I started processing those RAF files, they're not even that large but something about them makes Lightroom struggle. And judging by posts on photography forums, I'm not the only one either
I always wondered if it was a deadlock situation, because it doesn't spit out any overflow errors.