Workflow for RAF files taken with IR 72 filter in Darktable

Dear everybody,
I’m going to take images with my XT-2 with the 23mm F2 lens with a IR72 filter (infrared filter) of Hoya installed.
I ’ am searching for a good workflow in Darktable to convert the infrared RAF files in to B&W Jpeg’s…
Please let me know where i can find the information (instructions) needed. Or does somebody has experience with it in Darktable and send me his workflow.
Much appreciations upfront.
Greetings.

Dag!

I believe that @Thomas_Do knows a lot
ref Countryside in infrared
and perhaps @Daniel_Catalina
ref [PlayRaw] Infrared Fake Colors

And you have hopefully already seen this

MvG
Claes in Lund, Zweden

Hi Claes,
Everything OK?
Many Thanks for the update.
Now waiting for a good moment to shoot infrared.
So now is time to study the send info.
greetings

In case you have missed these:



Mvg
Claes in Lund, Zweden

1 Like

Hey, Ruud,

How did it go?

Mvg
Claes in Lund, Zweden

There were 2 discussions in French in which I participated:
https://forums.darktable.fr/showthread.php?tid=2538&highlight=infra
https://forums.darktable.fr/showthread.php?tid=2688&highlight=infrarouge
You can also see some infrared photos that I treated with darktable:
infrared photos

Hi Claes,
I did not found any ready made workflow.
So after some trail and error I do have the following workflow

  1. Compress history stack to “original”
  2. Use “input color profile module” and choose “Linear infrared BGR”
  3. Use " color contrast module" put both slider to at minimum 0,25 or lower (does give a shift on the colors.
  4. Use “filmic module” to my liking
  5. Use " equalizer module for “clarity” and “sharpen” the image
  6. Activate " Velvia module" to my liking
  7. Use White balance and choose “spot” this makes the image almost " B&W"
  8. Activate " monochome module"
    And we have our infrared B&W images.
    See two examples Do You like them?

2 Likes

Thank you for the update.
I did some experimenting and do the following in Darktable.
So after some trail and error I do have the following workflow

Compress history stack to “original”
Use “input color profile module” and choose “Linear infrared BGR”
Use " color contrast module" put both slider to at minimum 0,25 or lower (does give a shift on the colors.
Use “filmic module” to my liking
Use " equalizer module for “clarity” and “sharpen” the image
Activate " Velvia module" to my liking
Use White balance and choose “spot” this makes the image almost " B&W"
Activate " monochome module"
And we have our infrared B&W images. See below an example.

Greetings

Yes, I do!
I like the top one better – sort of more distinct?

Thanks​:hugs::hugs:

@RMA: Great image.

I would like to add examples for color images done with Hoya infrared filter R72. Although the example shot is not as impressive as yours :cry:.
20190419_0004.CR2 (24.6 MB)

Original:

To get foliage white and sky blue:
White balance, spot to foliage for white plants
Color zones, to increase the saturation of the sky
Channel mixer, RB-Swap for blue sky
haze removal & velvia to increase color saturation
tone curve for contrast


20190419_0004_01.CR2.xmp (4.5 KB)

Here an other version, type “ripe grainfield”:slight_smile: .
The settings are very similar to the first example. The main difference is the white balance, which was spot set to the the sky. Then some tweaking with tone curves etc. to get the settings right (see xmp file).


20190419_0004_02.CR2.xmp (7.2 KB)

These are just examples to demonstrate the principle, not fully developed images.

1 Like

Hi Thomas. Thanks for your info. I wil check this out with some new images soon. So if i understand correctly. With the channel mixer (never usef that) you can swap colors. I did use color contrast. But do not know if it will lead to the same results. Will check this all out. Many thanks.
Greetings. Ruud

Hi Thomas did do an image with your approach.
I like the grainy look of the image. Denoise does not make it better.
Do you like it?

3 Likes

I D/L your *.cr2 and I got pretty much the same within a Minute. But when I try mine the screen goes black when I do the white balance.

My image file is orignially in *.x3f format (Sigma) which dt/RT can’t handle. File is a converted halfsize TIFF. Filter is 720nm, exposure time is short, the camera had the hotmirror removed.

Your image has way less cast then mine. For b/w it works perfectly, but it’s color (like yours) I am after.

What is the trick to get a workable white balance? Neither dt nor RT worked for me here.

SDIM4125.tif (~28Mb)

Your image has nearly no signal in the green channel. I think it is not possible to set the WB by spot. What IR filter did you use?

How can you check this? Which channel has signal and which not? With the histogram or is there another method?

The Histogramm is useful and you could also use the channel mixer.

I increased the green channel with the channel mixer and saved the image as TIFF.
SDIM4125.tif.xmp (3.0 KB)

Afterwards it was easier to work with your image.


SDIM4125_02.tif.xmp (4.1 KB)

1 Like