Lens correction support for Fuji GF lenses

Software darktable
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Hello,

Amateur LrC user here mulling a move to Darktable.

May I ask; how does one work around the lack of lens correction support for the full range of Fuji GF lenses?

It’s great that the the 23mm, 45, 55, 80 and 110 are all supported, but I use the 63mm most and it’s not supported afaik. Similarly the 100-200mm.

Please forgive me if this is explained somewhere, I did search for this (darktable 4.6 user manual - lens correction) and the Lens Fun database, but couldn’t see these two lenses listed .

Many thanks!
Andrew

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Is lens correction metadata embedded in the image? If so, you don’t have to rely on lensfun.

Some Fujifilm cameras and lenses work well that way, at least according to this issue:

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Thanks Istvan, much appreciated!

I’ve yet to install Darktable (I failed at the first hurdles - my Mac skills are basic), so I don’t know and haven’t tried.

The camera can include EXIF data with each image import. Maybe Darktable can apply some corrections from this alone?

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I can pose this question to the FujiX-forum if that helps us establish what data the camera can provide with each file on import :slight_smile:

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It’s not that hard to shoot and submit the required images for adding your lenses to the database. Don’t have any of the tutorial links handy, someone else might…

Welcome to the forum!

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If you can post a raw here, I’ll be happy to run it through darktable to see if the lens correction module can work with the embedded data.

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btw: installing on mac can result in warnings regarding security, so hav a look at install | darktable

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Thanks all who’ve replied. Really grateful.

I’ll work through and provide individual replies once my health allows - I have ME/CFS and this means I don’t always have capacity right away.

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Thanks Glenn.

I’ve now had a chance (capacity) to look at the instructions (PIXLS.US - Create lens calibration data for lensfun) and all sounds sensible, but sadly as I’m house bound with poor health these steps are beyond my reach.

I could contribute RAW files of bathroom tiles, but I gather that’s not suitable.

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Wow thank you so much Istvan.

Due to a health condition I don’t have capacity to leave the house and gather images of architecture (for the straight lines), so I can’t contribute RAWs with anything other than bathroom tiles.

I can certainly share RAWs of this - or other suitable subject matter - and/or share via file transfer or something, as the files from the Fuji GFX are c.200MB uncompressed

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When using the embedded correction data (if darktable can handle your camera), you don’t need straight lines and architectural structures; those would be used to make a lensfun profile.

If you already have darktable working, you can try the lens correction module and see if it supports your camera. If you don’t have darktable yet, and don’t want to waste time if it does not support the camera, please share the files you’d normally process, and I can load them in the latest development version of the software to see if lens correction works.

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you can provide files to the raw samples here

and then others can check them for the needed metadata.

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Unless it is a new camera model (i.e. not present in the database), we don’t really need/care for more samples w/ different lenses on RPU…

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Thanks again Istvan, this is all incredibly supportive and kind!

My current camera is a Fuji GFX 100s, which is supported by darktable - which is great (camera support | darktable).

I’ve not been able to share a RAW file as an upload in the reply here, perhaps because 200MB is too large.

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I’ll get to this asap, thanks again Darix, this is all most helpful and beyond expecttions :slight_smile: :slight_smile: :slight_smile:

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At least for the GFX100S sample from RPU (which is taken w/ GF 45mm F2.8 R WR), the embedded metadata is available and can be used for correction:

image

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My ignorance kmilos - sincere apologies, I’m a luddite - could you kindly unpack the meaning/application of this?

(I think you’re saying that the 45mm’s embedded metadata is sufficient as standard to be used for correction?). If so, this probably holds true for the 63mm and 100-200mm lenses too.

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Correct, it should.

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Ah, yep, the instructions do compel using exterior-shot images. Now, I think that depends on the lens; with longer telephotos finding a long-enough space in the confines of a house would be problematic, but a shorter lens could be done.

I can see how bricks/tiles can be problematic; in another hobby I CAD-modeled such for making scale structures and I was compelled to put in an angle parameter that was used to randomly skew bricks for realism… :crazy_face: However, indoors one could run a tightly-tensioned string or somesuch to make decent straight lines.

I think the important point for distortion is to get a couple of straight lines positioned in the frame, sharply focused at a given focal length.

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