The RAW vs JPEG Debate

Compression must be done before the buffer otherwise continuous shooting in JPEG would have the same limitations as RAW.

I always shoot Raw with my Ist DL2 and K10D. However I use DNG with the K10D as I believe that it may be more future proof.
Will software be available to convert PEF in 10 years time?
I suspect that DNG will, as it is a Standard to be used by other manufacturers.

Any other thoughts on this?

Regards
Graham

There are two kinds of compression. "Lossy" compression works by discarding data that is deemed to be unnecessary - an example is a JPEG.

"Lossless" compression works by recording the data more efficiently, eg: "1 and 100 zeroes" instead of "1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000."

PEF files are losslessly compressed, so there is no image degradation.

Actually, it's probably quicker to compress, then save a small file, than to save a large file.

Now that K10D PEFs are widely supported there is no reason to use DNG. If you want to archive DNG files rather than PEFs, convert afterwards.

G

Just to add to this...
The JPG output is compressed and handled in circuit. The PRIME engine has a dedicated JPG conversion circuit that greatly speeds up the JPG. In fact, AFAIK the main CPU doesn't even have to get involved. That's why the K10D can rattle away in JPG mode and still be twiddling its thumbs

On the other hand the compressed PEF format is Huffman encoded (which is completely lossless) and I think has to be handled by the main CPU. As has been mentioned there is some tradeoff between the time to write an uncompressed file vs the time to do the compression.

And to repeat - Huffman encoding is lossless. Completely and utterly. What goes in, comes out - no bits changed at all. Nada. I can point you to the math if you want... but it's brain-ache stuff

Matt

Ok

I have just done a few PEF test shots and they will only open in the pentax software I have. Which I have to be honest I dont like.

They wont open in CS3 or Silkypix 3 so what software will they work with

Pete

They certainly do open in CS3. Do you have all the online updates?

And also in Picasa.

I use SilkyPix all the time for PEF files... one of the reasons I bought it was that it supported PEFs before I upgraded Photoshop. I also like the way SilkyPix works and its end result more than other software, but that is obviously secondary to being able to read the file format in the first place.

Try again, Pete. K10D PEFs work in all the main software packages. You might however, have a very early version of Silkypix (and CS3). I suggest you update.

G

Lightroom opens PEF files fine.

thanks all for the info, I'll try using PEF to get more on the card.

K10D PEFs open in:
Lightroom, Capture One LE, Silkypix, Photoshop CS2, Bibble, Picasa etc etc.

Are there any more??

BUT you have to have the later versions (or the latest!). For Adobe products you download the "Adobe Camera Raw" update - which is separate from the main product and can also include Adobe's stand alone DNG converter.

Latest version of Silkypix is 3.0.11 (think the K10D was supported from 3.0.9 or even . In fact Silkypix supported the K10D from the time the K10D was launched (not really any surprise there given the links between Pentax and Silkypix!).

Matt

Sometimes I need to just view the photographs taken by my K10D. I use FastStone Image Viewer faststone.org for this. But in general all my PEF files are well organized and viewed by PicaJet Photo Managerhttp://picajet.com. I am not a professional photographer although some of my art photographs win a couple of regional contests. But I recommend the above tools to handle your Pentax RAW and JPEG files. Another small tool which I use to automate converting PEF to DNG is RoboImport, check it also. [/url]

Mattmatic, Aperture is a RAW converter, that opens k10 raw files.
I'm not really a pixel peeper, but it works pretty good for my needs.

Mac Preview will also open RAW files for viewing, if you want to see what you have. I always use Bridge for viewing my RAW images.