Focal length distribution

Discussion in 'General Technical Discussion' started by Michael Mohrmann, Jun 16, 2007.

  1. I seem to recall a few posts displaying the percent (or number) of images by focal length breakouts (histograms). As I migrate from film to the D200, I'm curious to see which focal lengths I end up using.

    I have Opanda's IExif installed, but going through one image at a time is too time consuming. I was wondering if there is software out there that can produce these focal length distributions from a directory of JPEG and/or NEFs?
  2. Chris101


    Feb 2, 2005
    Last edited by a moderator: Mar 15, 2017
  3. Last edited by a moderator: Mar 15, 2017
  4. mkawa


    Apr 25, 2007
    San Diego, CA
    I hacked away at this a bit recently. One problem you may encounter is that RAW files don't have a standard EXIF format, and aren't read by either of the two programs mentioned.

    I played around with batching all my RAWs with dcraw and then running a standard EXIF reader at one point but didn't have the chutzpah. It turns out that there's kind of a clever trick: Lightroom (30-day trial available if you don't own it) uses a refreshingly standard sqlite DB that's relatively easy to access with an off the shelf sqlite binary. It also reads pretty much all your image formats and plugs the resulting metadata into its database in a similarly highly standard format. You can hopefully fill in the rest of the details with your imagination, but if you're using MacOS, you might find this page useful (although the R scripts won't run on a newer R runtime as is, it's an easy fix):
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