Pages: [1]   Go Down

Author Topic: Adobe Lens Profile Creator question.  (Read 4072 times)

Pete_G

  • Full Member
  • ***
  • Offline Offline
  • Posts: 244
    • http://www.petergoddard.org
Adobe Lens Profile Creator question.
« on: January 26, 2013, 11:48:37 AM »

I think I kinda understand how this software works. If I create sets of 9 images of a test chart at various apertures, I can create a lens profile
that, I presume, LR and ACR can use, reading the aperture from the EXIF and applying the appropriate data for that aperture to create a lens correction.

But how does the focus distance work, since within the fairly limited restrictions of shooting test charts the focus distance can only change by a small amount.
Am I to assume that ALPC uses this data and extrapolates it for focus distances far outside those used in shooting the charts, and finally, how important is it
in terms of the quality of the lens correction, to go this exta step of including different focus distances?  I'm profiling a prime lens only.
Logged
___________________
http://www.petergoddard.org

alan_b

  • Full Member
  • ***
  • Offline Offline
  • Posts: 178
    • http://www.alanbrandtphoto.com
Re: Adobe Lens Profile Creator question.
« Reply #1 on: February 21, 2013, 12:16:28 PM »

I have a related question about distortion/focus distance.  (Sorry if I'm hijacking!)

Can the lens profiles include variations by focus distance?  For example, I have problems using the Adobe profile for Nikon's 14-24/2.8.  In use, the profile overcorrects to a pincushion state.  I usually need to back off the correction amount to ~60%, which isn't perfect.

Is it even feasible to create a profile for a superwide at a far focus distance?  Seems like the target would be too small in the frame.

mlewis

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 86
Re: Adobe Lens Profile Creator question.
« Reply #2 on: February 22, 2013, 04:18:30 AM »

I have a related question about distortion/focus distance.  (Sorry if I'm hijacking!)

Can the lens profiles include variations by focus distance?  For example, I have problems using the Adobe profile for Nikon's 14-24/2.8.  In use, the profile overcorrects to a pincushion state.  I usually need to back off the correction amount to ~60%, which isn't perfect.

Is it even feasible to create a profile for a superwide at a far focus distance?  Seems like the target would be too small in the frame.
You can use different focus positions.  With a wide angle you are going to need a very big chart though. You don't have to use the Adobe supplied shooting charts - you can make your own if you need different sizes/grid sizes.
Logged

sampei

  • Newbie
  • *
  • Offline Offline
  • Posts: 1
Re: Adobe Lens Profile Creator question.
« Reply #3 on: May 31, 2013, 11:32:59 AM »

You can use different focus positions.  With a wide angle you are going to need a very big chart though. You don't have to use the Adobe supplied shooting charts - you can make your own if you need different sizes/grid sizes.

thank you so much!
Logged
Pages: [1]   Go Up