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How does lossless compression in Fuji RAF files work? (2020)

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Re: How does lossless compression in Fuji RAF files work? (2020)

#31

Post by Analemma_ »

guillego wrote: post #25
Analemma_ wrote: post #15

Earlier quoted context omitted.

I recently upgraded from an XT-3 to an XT-5, but loved my XT-3 and would still recommend it as a good purchase if you can find a decent deal on one in good condition. Fuji’s AF is not the best in the business, so I wouldn’t recommend one if you’re planning on using it for e.g. sports photography, but apart from that the XT series has no real downsides. The physical dials for ISO+exposure+shutter speed are fantastic a…

I have an XT-1 from 2015 (still working!) and recently started considering upgrading to an XT-5 but I'm a little hesitant to buy a "new" camera first released in 2023 that still retails for almost the same price as two years ago. I'm so torn between just going for it and waiting (who knows how long) for the X-T6 to come out. Perhaps I should just try to find a good deal on an X-T4.

If it helps, I pay reasonably close attention to Fuji rumors because I'm deep in the ecosystem, and at present there appears to be no indication that an XT-6 is coming any time soon. They just released the GFX100RF and XE-5, plus there are rumors of an X-T30 III soon, and with all that in the pipeline I doubt they are also finishing up an XT-6. The -4 and -5 are still great cameras, I would just go for whichever of those you think is a better deal.

Re: How does lossless compression in Fuji RAF files work? (2020)

#32

Post by smugglerFlynn »

gappa wrote: post #8
matja wrote: post #4

Earlier quoted context omitted.

Those discussions I feel are fuelled by manufacturers like Sony saying [0] things like: Lossless compressed RAW: ... This is a popular format that occupies less space with minimal quality loss. "minimal" "loss"? That's not "no loss", so what exactly is it? [0] https://www.sony.co.uk/electronics/support/articles/00257081

I actually asked Sony Support about that. Their reply: "We can confirm that with Lossless compressed RAW there is a minimal quality loss. To have no impact on image quality I suggest using Uncompressed RAW files." Lossless isn't what it used to be.

Seems you just got 1st line robo-reply repeating what public resources state. Does not say much about actual compression algorithm Sony uses.

Re: How does lossless compression in Fuji RAF files work? (2020)

#33

Post by jcynix »

yboulkaid wrote: post #16

I wonder if something about this explains why Fuji RAF files are the only RAW files that make Lightroom struggle. 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

Lightroom struggles with Fuji's unconventional sensor pattern. Other programs like Darktable, GraphicConverter, Luminar Neo or FastRawViewer don't make fans of my M1 audible.

Re: How does lossless compression in Fuji RAF files work? (2020)

#34

Post by _7acn »

yboulkaid wrote: post #16

I wonder if something about this explains why Fuji RAF files are the only RAW files that make Lightroom struggle. 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'm not sure what causes the terrible RAF handling in Lightroom, but it's a fairly well-known issue. Lightroom produces so-called "worming" and apparently this is related to the X-Trans sensor which requires a different decoding algorithm. On my end, I can recommend Capture One - the handling here is perfect, though you do have to get used to the UI unfortunately

Re: How does lossless compression in Fuji RAF files work? (2020)

#35

Post by matja »

Scaevolus wrote: post #29
matja wrote: post #4

Earlier quoted context omitted.

Those discussions I feel are fuelled by manufacturers like Sony saying [0] things like: Lossless compressed RAW: ... This is a popular format that occupies less space with minimal quality loss. "minimal" "loss"? That's not "no loss", so what exactly is it? [0] https://www.sony.co.uk/electronics/support/articles/00257081

A lot of cameras write "lossless" to mean "perceptually lossless". This is easy to do because ~12-bit ADCs have lots of noise in the low order bits.

"lossless" has always referred to compression, not sampling - but it seems camera manufacturers want to change that for marketing reasons.

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.

Re: How does lossless compression in Fuji RAF files work? (2020)

#36

Post by smugglerFlynn »

guillego wrote: post #25
Analemma_ wrote: post #15

Earlier quoted context omitted.

I recently upgraded from an XT-3 to an XT-5, but loved my XT-3 and would still recommend it as a good purchase if you can find a decent deal on one in good condition. Fuji’s AF is not the best in the business, so I wouldn’t recommend one if you’re planning on using it for e.g. sports photography, but apart from that the XT series has no real downsides. The physical dials for ISO+exposure+shutter speed are fantastic a…

I have an XT-1 from 2015 (still working!) and recently started considering upgrading to an XT-5 but I'm a little hesitant to buy a "new" camera first released in 2023 that still retails for almost the same price as two years ago. I'm so torn between just going for it and waiting (who knows how long) for the X-T6 to come out. Perhaps I should just try to find a good deal on an X-T4.

Innovation is very slow in photography world these days, X-T5 made a big jump in MP count compared to X-T4, but resolution aside image quality is pretty much the same, and other improvements were marginal.

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.

Re: How does lossless compression in Fuji RAF files work? (2020)

#37

Post by _7acn »

vadansky wrote: post #12
the_lucifer wrote: post #6

As someone who shoots on Fujifilm (XT-3), this was an intensely fascinating read. Thanks, now I have half a mind to sit down and re-implement this code, just to get a feel of how it works.

I've been thinking of buying that camera for a while, do you recommend it? Do you have anything to say that will finally push me over the edge to actually but it?

I own 4 Fujifilm cameras and personally, I'd recommend being VERY careful and thinking hard about this purchase. This isn't the same Fujifilm as it used to be. The company was once known for its "Kaizen" approach, which has long since disappeared. Prices are now inflated because they're riding on popularity. Autofocus in Fuji is simply weak.

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.

Re: How does lossless compression in Fuji RAF files work? (2020)

#38

Post by jcynix »

vjvjvjvjghv wrote: post #2

There are always these crazy discussions in photo forums where people are arguing that uncompressed RAW files are better than lossless compressed.

These forum discussions seem unconnected to reality IMO. Sometimes funny, more often strange, like audiophile discussions about oxygen free copper cables. Why?

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.

Re: How does lossless compression in Fuji RAF files work? (2020)

#39

Post by graemep »

tecleandor wrote: post #20
manoDev wrote: post #7

Earlier quoted context omitted.

It’s because manufacturers keep inventing their own formats instead of using plain DNG, and you can only figure out the difference reverse engineering the file. Even for the same manufacturer and file type, they may change encoding details between models or firmware revisions. 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…

DNG license might include some legal stuff that probably they don't want in their devices. https://helpx.adobe.com/camera-raw/digital-negative.html#dng

What is the problem there? It essential provides an unlimited license any Adobe patents needed to implement DNG, and revocation if you assert a patent against Adobe related to DNG.

Re: How does lossless compression in Fuji RAF files work? (2020)

#40

Post by LeifCarrotson »

jcynix wrote: post #38
vjvjvjvjghv wrote: post #2

There are always these crazy discussions in photo forums where people are arguing that uncompressed RAW files are better than lossless compressed.

These forum discussions seem unconnected to reality IMO. Sometimes funny, more often strange, like audiophile discussions about oxygen free copper cables. Why? 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 obvious…

I almost never look at full images in 1:1, either, but I find very often that I have the wrong lens for an application and/or the wrong exposure.

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.

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