Olympus 12-40mm Calibration from Darktable, [RESOLVED]

[springm]

***please see the last post in this thread***

Darktable has calibration values in xml-format for the Oly M.Zuiko 12-40mm, which I translated into AfterShotPro syntax:

begin lens
group: micro43
multiplier: 2.0
aperture: 2.8
calibrated: true
menu_lens: M.Zuiko Digital ED 12-40mm F2.8 PRO
cal_abc: 12.0 0.03659 -0.11322 0.0294
cal_abc: 19.0 0.00375 -0.0151 -0.01028
cal_abc: 26.0 0 -0.00273 0
cal_abc: 32.0 0 0.00212 0
cal_abc: 40.0 0 0.00408 0
end

If I insert this in profile_micro43.txt, I can manually select this lens for the images I take with the OM-D M5.

With exiftool I extracted the LensID 0 19 10, but if I insert the line

0 19 10|M.Zuiko Digital ED 12-40mm F2.8 Pro

into profile_olympuslenstable.txt, the lens won't get automatically selected.
Does anybody have a different LensID for the 12-40mm, or another idea how to get it to be recognized automatically by AfterShot?

---Markus

[springm]

Nobody any idea about the LensID setting for the 12-40mm?

[nex4]

Sorry, I cannot offer much help.

I am just wondering where you obtain your lens profile data? Where is this Darktable? I am looking for lens profile for Sony E-mount 16-50mm kit lens. I found one from lensfun but I don't think it is accurate.

[springm]

http://www.darktable.org/install/

With some effort you can even get it to work under Window$.

[nex4]

I took at look at the link and there are some reference to lensfun. And your len's data matches exactly to lensfun's database. So I guess I won't do much better unless ASP is interpreting the parameters wrong.

http://svn.berlios.de/wsvn/lensfun/trun ... lympus.xml

<maker>Olympus</maker>
<model>Olympus M.Zuiko Digital ED 12-40mm f/2.8</model>
<mount>Micro 4/3 System</mount>
<cropfactor>2.0</cropfactor>
<aspect-ratio>4:3</aspect-ratio>
<calibration>
<!-- Taken with OMD E-M1 -->
<distortion model="ptlens" focal="12" a="0.03659" b="-0.11322" c="0.0294" />
<distortion model="ptlens" focal="19" a="0.00375" b="-0.0151" c="-0.01028" />
<distortion model="ptlens" focal="26" a="0" b="-0.00273" c="0" />
<distortion model="ptlens" focal="32" a="0" b="0.00212" c="0" />
<distortion model="ptlens" focal="40" a="0" b="0.00408" c="0" />

[springm]

Certainly not all calibrations are of the same quality, but those of the 12-40mm are good. It all depends on the person who did the calibration.

You might do some calibration images of your own and send them to Thorsten Bronger, indicating that the present calibration data needs improvement:

http://www.darktable.org/2013/07/have-y ... alibrated/

Or you do it yourself with along the recipe: http://forum.corel.com/EN/viewtopic.php?f=95&t=45815

---Markus

[jgbc]

What you have done should work for new pictures, but if the picture has already been opened in Aftershot you will need use the "Reload EXIF" button for the new profile to be used. Have you tried that?

[springm]

Yes, I've tried that - unfortunately without success.

---Markus

[jgbc]

I have added the profile to my profile_micro43.txt and profile_olympuslenstable.txt. My profile files contains various error fixes and some additional lenses.

Could you check if that works... unfortunately I don't own the 12-40 lens?

Remember to backup you existing files

[springm]

Thanks for your efforts!

I downloaded both files and put them into the correct folder.

Now I can select the 12-40mm by hand, but it is still not recognized automatically when clicking the 'reload exif' button.

I have uploaded a test file on my server so you can try yourself:

http://markus-spring.info/varia/20140501-150811mws.ORF

In the past I've tried a lot of different settings, but AfterShot always had bulked to recognize this lens automatically.

Best regards

Markus

[jgbc]

I think the lens id is wrong it should be 0 25 16.

Try the attached files.

[springm]

Yes, indeed, that was my mistake - now it works.

Thank you very much!

Just out of curiosity: how did you retrieve the lens id?

Best regards - Markus

[jgbc]

I started using exiftool, but that shows the same id you posted. Then I tried googling the lens, and found the id on a Flickr page... not an ideal solution for finding lens id's but it worked.

[jgbc]

It seems you have covert from hex to dec:

19 hex = 25 dec
10 hex = 16 dec

[springm]

OK - that looks quite logical.

Thanks again!

Markus