Sunday, March 9, 2008

K20D File Sizes and Formats

I wanted to do a bit of a comparison of the filesizes that are created by this new 14 mega pixel monster. My testing was pretty simple. Tripod setup, facing a dull and boring corner of the office, set to the first image quality setting, take a shot, next setting, etc. Then take out the card and put the filesizes into a chart that I can then share with you. There will no doubt be minor differences in filesize if other people look at this test due to the image contents, type of SD card, etc etc.

First, a bit about the different settings. The K20D has the following capture options:

  • JPEG
  • RAW
  • RAW+
And each of those have options.
  • JPEGs can be captured at 2 MP, 6 MP, 10 MP and 14 MP, and at each of those settings you can have different detail qualities, *, **, ***, and ****.
  • RAW can capture in PEF (the Pentax RAW format) or DNG (the adobe designed open standard for RAW data capture. All RAW data is captured at 14 mega pixels.
  • RAW+ (ie: RAW and JPEG together) can be either PEF or DNG, as well as having all the JPEG options available (2mp to 14mp and * to ****).

That's a lot of options when you put them all down in a grid!

Update: Please note that according to this thread the methodology I used (trusting the camera's image remaining calculation) is innaccurate. I'll be testing again tonight by actually taking pictures to hopefully get some "real" data.

Update #2: Updated the pure RAW DNG/PEF numbers... DNG was the same, PEF gives you almost double what it predicts. I'm not going to shoot the tens of thousands of shots to calculate out all the options, I don't want to wear down the shutter! However, I'm going to add another column with the math based on the average image size based on a 4GB card giving you 4,094,855 (approx) KB.

on 4GB Card

FormatSize (KB)PredictedCalculatedTested


















RAW DNG23,605170173170



































A few thoughts and notes.

First of all, as of now, the K20D PEF format is not recognized by Adobe Camera Raw, so programs like Photoshop and Lightroom are unable to open the PEF files. The DNG files can be opened of course, but at the expense of almost 10mb per image file. Also, the K20D created DNG files can be opened directly with the Adobe DNG converter, and they can be converted down to 13mb from the 23mb they come from. They are probably stored uncompressed for speed.

Also, the K20D DNG files can be converted to compressed (or at least smaller) DNG in Lightroom if you select the 'convert to DNG' option when doing an import.


Anonymous said...

So you finally got one!
Looking forward to seeing aome hi quality mere 10 Mpx cannot compare.
Best from Thailand, overcast, thus photos will be strangely flat tho' local use of garish colour somewhat makes it better. Many strange and wondrous things.