Convince lens manufacturers to provide calibration data

[Vente]

@europlatus

In the past, I’ve found by the time I get around to this kind of thing, someone somewhere has already submitted the lens data so I don’t need to bother

I’ve got the 24-70mm f/4 knowing it’s already in lensfun, but the profile turns out to be suboptimal at best. So I was forced to do one myself anyways…

That’s why I want to find a building that’s okay to photograph in a way that’s awkward to anyone watching me and not depend on lensfun (which kinda defeats its purpose for me a bit)

[mensch_plus_kamera]

That’s the tricky points:

• Find a suitable building front with discernible straight horizontal lines
• Be able to set up a tripod at different distances in front of it
  • Head on, so the horizontal lines do run horizontally through the frame
  • Different distances to account for different focal lengths of a long telezoom
  • Don’t get run over by a bus while taking pictures at different apertures for a focal length that puts you close to or on the road.
• Convince police arriving at the scene that what you’re doing is gathering lens characteristics data for an open source project, rather than gathering information for some sort of criminal activity.

[Vente]

@mensch_plus_kamera

Convince police arriving at the scene that what you’re doing is gathering lens characteristics data for an open source project, rather than gathering information for some sort of criminal activity.

I see you are very familiar with the struggles

@mensch_plus_kamera

Don’t get run over by a bus while taking pictures at different apertures for a focal length that puts you close to or on the road.

This may be the biggest one. I’ve found plenty of buildings with suitable horizontal lines where the optimal spot for shooting wide focal lengths is in the middle of a 4-lane road. The best bet are wide buildings with parks or small squares in front of them. I’ve found ONE such building, so wish me luck. Furthermore, there should be few concerns about the police being called on me…

[mensch_plus_kamera]

@Vente

Furthermore, there should be few concerns about the police being called on me…

Carefully choosing your outfit may help…

[Vente]

I have been asked a few times whether I am a news photographer or someone commissioned to document stuff maybe I could put on a reflective vest to further improve this impression…

[europlatus]

As long as it’s not JUST a reflective vest, because then the police will definitely be called

[Entropy512 (Andy Dodd)]

@Vente

Nikon cameras include image correction coefficients in EXIF, but they’re in a format not recognized by Darktable. If we had the algorithm for how these values work, a lot of lenses would be covered at once.

Same for Sony, and the format has been mostly reverse engineered, however it’s in a form that isn’t easily translatable into lensfun models without doing a bunch of curve fitting hacks