[dlacouture]

WheresWaldo : please check with the k20, but with the k10, it's better to shoot DNG (card space apart), then import and convert it to DNG (!) via Adobe CR converter...

Sounds dumb, but you can gain some extra pixels via DNGRecoverEdges this way...

[flyer]

Re-reading this thread, I realized I made a serious mistake. I confused PEF and DNG files, which are more or less the same, for sRGB and aRGB color spaces, which are different. I'm sorry for the confusion that might have come up because of my mistakes. PEF and DNG are essentially two different ways to save the same information, as sRGB and aRGB are two different ways (with different results) to show the information. I guess I was more tired than I thought when I wrote my previous post.

[ve2vfd]

Wow, loads of awesone information!

I guess in the end I'll stick to PEF as thats what I've been using for a while and my system is already set up for it.

Thanks everyone!!!

Pat

[Lazaruscomeout]

I recommend shooting in DNG or converting to DNG in Photoshop.

I shoot in DNG and when I process my RAW files, Photoshop automatically compresses (losslessly) the DNGs when I close them. They end up around 9 0r 10 MB in size on my hard drive, which makes storage alot cheaper. I also know that I'll be able to use them for years to come.

Gerry

[WheresWaldo]

Re-reading this thread, I realized I made a serious mistake. I confused PEF and DNG files, which are more or less the same, for sRGB and aRGB color spaces, which are different. I'm sorry for the confusion that might have come up because of my mistakes. PEF and DNG are essentially two different ways to save the same information, as sRGB and aRGB are two different ways (with different results) to show the information. I guess I was more tired than I thought when I wrote my previous post.

I am glad you saw that. It is sometimes hard to draw the line when trying to correct an error. Sometimes the terminology messes us up as so many terms, even incorrectly, are used interchangeably.

[WheresWaldo]

WheresWaldo : please check with the k20, but with the k10, it's better to shoot DNG (card space apart), then import and convert it to DNG (!) via Adobe CR converter...

Sounds dumb, but you can gain some extra pixels via DNGRecoverEdges this way...

There are two fields in the DNG spec that address extra pixels DefaultCropOrigin and DefaultCropSize they are both used as, according to Adobe:

Raw images often store extra pixels around the edges of the final image. These extra pixels help prevent interpolation artifacts near the edges of the final image.

DefaultCropOrigin specifies the origin of the final image area, in raw image coordinates (i.e., before the DefaultScale has been applied), relative to the top-left corner of the ActiveArea rectangle.

So if there is a difference in pixel area I would be suprised if it is significant. Either way you do not do yourself a disservice if you choose PEF or DNG as your default. I will also do a little experiment to see if this difference exists in the K20 and/or in converted PEFs.

[shuie]

Whats this about not being able to view PEFs on a 64 bit computer? I downloaded the codec and windows will display my PEF's on my 64 bit Vista machine. I do use a K10 not a K20 so I don't know about those images.

[WheresWaldo]

Whats this about not being able to view PEFs on a 64 bit computer? I downloaded the codec and windows will display my PEF's on my 64 bit Vista machine. I do use a K10 not a K20 so I don't know about those images.

The codec is for Windows Explorer (not Internet Explorer) and applications like Windows Photo Gallery not for Pentax applications or things like Adobe Photoshop or Lightroom. The current Pentax codec will install on Windows Vista 64 but won't display the preview image in Explorer. At least not on the K20 PEFs. That has zero effect on whether or not LR or PFB or PPL will open them. Adobe does not have a 64 bit DNG codec.

[photog]

Hi whereswaldo and Jim Royal
You wrote:On a side note. I use Adobe LR and I would rather work with DNG than PEF, but I shoot only PEF. Reason is the lossless compression. I can get twice as many, or more, images on a card during a shoot using PEF. During downloading from the card I convert them automagically to DNG. Hard drive space is cheap, but that doesn't really matter either as LR will convert and compress it's DNG files. The best of one world!
I agree with you in every detail! Neither PEF or DNG in camera is better or worse than the other. Lossless means exactly what it says!
BTW I am also using LR 2 (.3) and PS4 Extended. How much better can it get?
Ron McDermott
Sunny Queensland - Australia

[dlacouture]

Regarding this question, here are my findings on my K20 :
- PEF is 40-60% smaller (so you have to convert the DNGs to DNGs (sounds silly?) to recover the lost space)
- DNG has the black, masked border pixels in it (thus edges cannot be recovered)
- DNG stores more EXIF-like information
- DNG has the embedded color profile (used in ACR/LR)

So, I reverted to PEF as it allows me :
- to recover the edges (but not much, anyway : 16x12 pixels only are hiding, so only 1% in total : 143k Pixels on a 14.3MP sensor...)
- to preserve more SD space (nearly twice the shots!)

But I miss the embedded color profiles of DNGs...

[rawr]

As I understand the issue...

Camera makers that use the DNG format create their (in-camera) DNG files with uncompressed sensor data, which is what Adobe recommends.

That is to say, when RAW sensor data is stored to DNG in-camera, it usually is a straight dump of the uncompressed sensor data. This is mainly for performance reasons - doing lossless compression on huge binary files is computationally intensive and doing it in camera isn't always a good idea if you want to retain camera responsiveness.

Upon secondary processing out of camera compression may indeed be applied to the DNG file- eg within Lightroom or whatever. Here the DNG specification includes the specification of a lossless compression algorithm to be used for the sensor data as standard.

RAW data saved as PEF in-camera may be subject to some lossless compression, but I'd also be surprised if it that was the case.

Out of camera what happens to PEF and DNG files - anything goes, of course.

[dlacouture]

What I know is that :
- Theorical size of a 14.3MP 12bits RAW file is ~20.5MB, plus the embedded JPG preview...
- K20's DNGs are ~23Mb.
- K20's PEFs are ~11-14MB.

So the PEFs are compressed (that was not the case with the k10, if my memory is good).

[attack11]

k10d vs k20d for format compression is about the same ratio. my 10MP dngs avg 16.5MB, pef are 10-14MB. those dng can be compressed down to 5-6MB losslessly.

the pef are compressed in camera vs the dng dump, so there is an advantage for dng; you can fit more into the camera buffer 'cause it clears faster. that's the case for the k10d atleast. the difference is a few pictures, but if you're mashing the shutter release it can be the difference between getting a shot off or waiting for the buffer to clear.

sdhc cards are cheap too compared to hdds. a 16gb class6 card should be in every camera these days if you're shooting raw.

[rfortson]

I shoot in PEF for the smaller size on the SD card, and then convert to DNG when I import (for smaller size on the hard drive). The DNGs on your computer are losslessly compressed, but the DNGs in your camera are not. I've done this since I started working with Adobe Lightroom 2.

[photog]

dlacouture wrote: "So the PEFs are compressed (that was not the case with the k10, if my memory is good)."
Just a quibble really... You made good sense bit I have both a K10D and a K20D. Both compress the PEF file, probably to about the same degree. Aftrer doing a number of tests in the early days I settled down to actually taking pictures most in PEF. The save time was never a problem. However considering the save time of the larger file as an issue and the size of currently available 16 GB cards (50 Aust$ - about 40 US$) DNG is the best choice for the K20D.
Good shooting
Ron McDermott
Sunny Queensland, Australia