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11-16-2008, 06:57 PM   #31
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QuoteOriginally posted by Marc Sabatella Quote
Any software that can view a PEF must uncompress it internally. If you mean, ncompress and then write out a new uncompress version of the file, I can't imagine such software would exist - there would no market for it. I can just see the ads: "run our software on your files to make them bigger, with no advantage gained whatsoever!" :-)
all the same a software switch in camera to say NO compression wouldn't hurt.
There odd (to me) statement in Richard,s bubble is what tweaked my curiosity..
I assume reversable compression implies "lossless"


Last edited by jeffkrol; 11-16-2008 at 07:59 PM.
11-17-2008, 12:04 PM   #32
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QuoteOriginally posted by jeffkrol Quote
all the same a software switch in camera to say NO compression wouldn't hurt.
There odd (to me) statement in Richard,s bubble is what tweaked my curiosity..
I assume reversable compression implies "lossless"
I have no idea about the "reversable" statement in the bubble. It is taken from a Pentax Powerpoint presentation.

I agree with Mark that such an option would not be much use, I can't think of any! I'm pretty certain that the PEF compression is indeed "lossless".
11-17-2008, 01:01 PM   #33
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QuoteOriginally posted by jeffkrol Quote
all the same a software switch in camera to say NO compression wouldn't hurt.
I suppose not. But if you like having your files bigger for no good reason, you can always shoot DNG (and at least you'd arguably gain something in the process).
11-17-2008, 09:48 PM   #34
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QuoteOriginally posted by Marc Sabatella Quote
I suppose not. But if you like having your files bigger for no good reason, you can always shoot DNG (and at least you'd arguably gain something in the process).
Unfortunately that would mean trusting Adobe. Don't mean to sound paranoid....
Compressed 12 bit PEF's would not be much larger than my ist-D 16bit (whole bunch of zero's) 6MP files. Of course memory prices are Magnitudes cheaper now than then.
12.5MB +/-.............
I mean why even bother to spend the CPU time to compress the file......
DNG's are roughly 24MB
Compressed PEF 12-18MB
Uncompressed would be 21.8 +/- approx.
Compressing will save you 20-50% of the card space roughly, if I figured this right......
K20D RAW file sizes? - Photo.net Pentax Forum
Megapixel Calculator - digital camera resolution | web.forret.com
OK....... guess the compression is lossless:
http://forums.dpreview.com/forums/read.asp?forum=1036&message=28787048&q=pef+compression&qf=m
K10D and newer (K20D and K200D) PEF files use absolutely lossless compression where as the DNG's from these cameras just use byte packing so that the 12-bit output from two photosites fit into three bytes, which of course is also lossless............
Nikon's virtually lossless compression loses nothing of any real value in that the codes that are eliminated are all toward the bright end of the scale where the codes are compressed together in image raw conversion anyway by the application of a normal monitor type tone response curve.

BUT please note the Nikon statements.... the root of my paranoia...... anytime you use the term "virtually"



OK so which method??????????
http://en.wikipedia.org/wiki/Category:Lossless_compression_algorithms


Last edited by jeffkrol; 11-17-2008 at 10:04 PM.
11-18-2008, 01:18 PM   #35
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QuoteOriginally posted by jeffkrol Quote
Unfortunately that would mean trusting Adobe.
No, it would mean trusting the ISO, since DNG is basically an ISO standard at this point. I don't think it has been ratified yet, but it was submitted a while back, and as far as I know, is working through the process just as smoothly as happened with PDF (another format that many erroneously assume to be under Adobe's control).
11-18-2008, 02:16 PM   #36
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QuoteOriginally posted by Marc Sabatella Quote
No, it would mean trusting the ISO, since DNG is basically an ISO standard at this point. I don't think it has been ratified yet, but it was submitted a while back, and as far as I know, is working through the process just as smoothly as happened with PDF (another format that many erroneously assume to be under Adobe's control).
It may never be ratified. Adobe also reserves the right to "change" things.
I'm not going to get into a "open raw" vs Dng discussion but not only does adobe reserve the right to change things, manufactures reserve it as well, leading pretty much to the same thing as propitiatory RAW, again.
I'll leave it to my own belief that the concept of DNG is good, the execution is bad.
Besides there are still hassles w/ compressed vs uncompressed ect....
There are plenty of other , better containers out there......... just not popular ones.
http://www.openraw.org/node/1482
In many ways, DNG can be viewed as simply yet another RAW format with undocumented information - except that DNG has the added risk that information can be lost during conversion to/from DNG and other RAW formats.
From a software developer point of view, DNG is a step backwards. From a camera manufacture's perspective, DNG does not address the missing elements in EXIF.
From a photographers perspective, DNG is dangerous because people believe they are storing for the future with the format, when nothing could be further from the truth.
11-19-2008, 02:19 AM   #37
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QuoteOriginally posted by Marc Sabatella Quote
No, it would mean trusting the ISO, since DNG is basically an ISO standard at this point. I don't think it has been ratified yet, but it was submitted a while back, and as far as I know, is working through the process just as smoothly as happened with PDF (another format that many erroneously assume to be under Adobe's control).
QuoteOriginally posted by jeffkrol Quote
It may never be ratified. Adobe also reserves the right to "change" things.
I'm not going to get into a "open raw" vs Dng discussion but not only does adobe reserve the right to change things, manufactures reserve it as well, leading pretty much to the same thing as propitiatory RAW, again.
I'll leave it to my own belief that the concept of DNG is good, the execution is bad.
Besides there are still hassles w/ compressed vs uncompressed ect....
There are plenty of other , better containers out there......... just not popular ones.
Notes on the future of Open RAW formats, and a look at DNG (by Stuart Nixon) | OpenRAW
In many ways, DNG can be viewed as simply yet another RAW format with undocumented information - except that DNG has the added risk that information can be lost during conversion to/from DNG and other RAW formats.
From a software developer point of view, DNG is a step backwards. From a camera manufacture's perspective, DNG does not address the missing elements in EXIF.
From a photographers perspective, DNG is dangerous because people believe they are storing for the future with the format, when nothing could be further from the truth.
Although I couldn't care less what people use as their format of choice, I agree with Jeff's viewpoint. If I had to lose one of the Raw formats on my K10D & K20D, it would be, inside a heartbeat, DNG.

That's the last of my sixpence worth - Over and out!
11-19-2008, 08:21 AM   #38
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[QUOTE=Richard Day;319628]Yes it is.

You may find the following information useful:

Richard,

Going a bit off topic here, but not way off topic. I used to shoot pef and then started shooting dng in camera on the k20d. When I upload my photos to my computer I upload them to a folder and from that folder, import them into lightroom without moving them from my preferred cataloging. I like having my own filing system. I know I can upload directly off the card from pef's into lightroom and convert on import to dng but how do I keep my file's in my neat file structure like I have it now? Or can I import directly into lightroom and also keep my preferred archive file structure as I have now? The whole reason I have switched to shooting dng is because lightroom keeps all information directly inside that file when I've edited, the pef raw files when processed have a sidecar file instead. I like having the complete information in one file. Seems neater to me. But I must say the dng files are huge and fill up my card faster than pef.
Can you shed any light on this for me?

11-19-2008, 08:36 AM   #39
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QuoteOriginally posted by LaRee Quote
Richard,

Going a bit off topic here, but not way off topic. I used to shoot pef and then started shooting dng in camera on the k20d. When I upload my photos to my computer I upload them to a folder and from that folder, import them into lightroom without moving them from my preferred cataloging. I like having my own filing system. I know I can upload directly off the card from pef's into lightroom and convert on import to dng but how do I keep my file's in my neat file structure like I have it now? Or can I import directly into lightroom and also keep my preferred archive file structure as I have now? The whole reason I have switched to shooting dng is because lightroom keeps all information directly inside that file when I've edited, the pef raw files when processed have a sidecar file instead. I like having the complete information in one file. Seems neater to me. But I must say the dng files are huge and fill up my card faster than pef.
Can you shed any light on this for me?
LaRee, I am not Richard but let me tell you how I do it. I shoot PEF only. PEFs are compressed so I can save more images on the card. I add a step to the file move process right at the beginning. After inserting my SDHC card in a reader I open Adobe DNG Converter. From their I copy from my source directory, the SDHC card, to my destination directory, on my HDD in the folders I specify. Adobe DNG Converter will copy and convert all the PEFs into compressed DNG files about the same size as the original PEF. I take this extra step for several reasons. First, I geocode many of my images and the application I use to do that does not support PEF but does support DNG. The second is that like you I do not like the sidecar XML file. I would rather have all my editing information stored within the DNG.

So to summarize:
  1. PEF to shoot, minimizes space taken on SDHC cards and Pentax knows how to do PEF better than their poor implementation of in-camera DNG.
  2. Convert to DNG on copying to HDD. I then discard the PEF file. If I was really anal about keeping the PEF I could always include it in the DNG, but I don't see the necessity for this step.
  3. Do all image, metadata editing on the DNG and use it for archival purposes.
11-19-2008, 08:42 AM   #40
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The problem with Jeff's source, is that is entirely based on old outdated information. Once submitted and approved by ISO, Adobe gives up the rights to arbitrarily change the format. Every revision to the format must be approved by ISO, even minor ones! Some of the technical aspects may still apply such as missing manufacturers specific metadata, but those things usually get addressed by ISO in their approval process and subsequent RFCs.

Besides, the source he is using also had his own agenda that he was promoting. To create another "standard" RAW format apart from what had already been done by others. Hardly an unbiased opinion.
11-19-2008, 09:03 AM   #41
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QuoteOriginally posted by WheresWaldo Quote
LaRee, I am not Richard but let me tell you how I do it. I shoot PEF only. PEFs are compressed so I can save more images on the card. I add a step to the file move process right at the beginning. After inserting my SDHC card in a reader I open Adobe DNG Converter. From their I copy from my source directory, the SDHC card, to my destination directory, on my HDD in the folders I specify. Adobe DNG Converter will copy and convert all the PEFs into compressed DNG files about the same size as the original PEF. I take this extra step for several reasons. First, I geocode many of my images and the application I use to do that does not support PEF but does support DNG. The second is that like you I do not like the sidecar XML file. I would rather have all my editing information stored within the DNG.

So to summarize:
  1. PEF to shoot, minimizes space taken on SDHC cards and Pentax knows how to do PEF better than their poor implementation of in-camera DNG.
  2. Convert to DNG on copying to HDD. I then discard the PEF file. If I was really anal about keeping the PEF I could always include it in the DNG, but I don't see the necessity for this step.
  3. Do all image, metadata editing on the DNG and use it for archival purposes.
Thank you, that sounds like it would be a good work flow for me. So I assume I can download the adobe converter you are talking about with a search right?
Thank you again for sharing your process.

edit p.s. I downloaded Adobe 5.1 raw converter and will try it out when I get off work. Thank you again!
I just looked at your blog. YIKES! That dog bite really did swell in a hurry. I hope you are ok now.

Last edited by LaRee; 11-19-2008 at 09:11 AM. Reason: p.s.
11-19-2008, 09:09 AM   #42
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LaRee, Adobe lists it together with Adobe Camera Raw. I don't think you can get it separate from ACR. So if you go to the ACR download link and download the combined ACR/ADC.

Adobe - Adobe Camera Raw and DNG Converter : For Windows
11-19-2008, 09:53 AM   #43
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QuoteOriginally posted by WheresWaldo Quote
The problem with Jeff's source, is that is entirely based on old outdated information. Once submitted and approved by ISO, Adobe gives up the rights to arbitrarily change the format.
That's my assumption too. Certainly that's the case with every other ISO standard - I'm not aware of any ISO standards that allow one company to arbitrarily change things (and I've been involved in several standardization efforts in the past). But I haven't totally followed this particular process, so perhaps there is some more recent insider info Jeff is aware of.

QuoteQuote:
The problem with Jeff's source, is that is entirely based on old outdated information. Once submitted and approved by ISO, Adobe gives up the rights to arbitrarily change the format. Every revision to the format must be approved by ISO, even minor ones! Some of the technical aspects may still apply such as missing manufacturers specific metadata, but those things usually get addressed by ISO in their approval process and subsequent RFCs.

Besides, the source he is using also had his own agenda that he was promoting. To create another "standard" RAW format apart from what had already been done by others. Hardly an unbiased opinion.
Right. That site is *hopelessly* behind the times. In fact, as far as I can tell, OpenRAW is dead. The last update to the site was *over two years ago* - well before the ISO standardization of DNG began. So if one's only source of info on DNG comes from there, it is essentially worthless. My guess is these folks lost interest and threw in the towel when Adobe submitted DNG for ISO standardization and just never bothered to post an update.

But let's say, for the sake of argument, that the ISO standardization fails, and Adobe does retain control of DNG. In that case, yes, of course, there would be some risk. But there is another risk worth mentioning mentioning, much as we don't like to consider it: the possibility that Pentax goes out of business, leaving PEF an orphaned format. If I were in the worrying-about-what-bad-things-could-possibly-happen-in-the-future business, this would probably concern me more than anything Adobe might do.

As I have said before when the subject comes up, my crystal ball sucks. I have absolutely no idea which format is more likely to be viable in the future. But neither does anyone else. It's just guesswork. My guess is that both formats will continue to be viable for as long I need them to be. I can't prove that, but nor can anyone prove to me that their favorite format is more likely to survive.

So the bottom line as I see it is this: there is absolutely no way to know what the future holds, and nothing I've seen thus far seems even remotely convincing one way or the other. So making a format decision based on what amounts to, essentially, non-information, strikes me as pointless.

As far as I am concerned, the choice between DNG and PEF should not come down to concerns about the future. It should be based on the more concrete factors. The fact that DNG is not compressed in camera but PEF is - that is something that can and should influence which you shoot. The fact that PEF can be converted to DNG after the fact and yield even better compression at the expense of some computer processing time - that is also worth considering. The fact that you can store IPTC and other metadata, processing parameters, and even an adjusted preview directly within the DNG file (no sidecar files required) - that is also worth considering. But the fact that this makes DNG slower to work with than PEF, because updates can require re-writing the file - that's also worth considering. These are all legitimate objective facts that can be used in deciding which fits your workflow better, and in my mind, they *far* outweigh any guessing about what might happen 20 years from now.

FWIW, I shoot PEF. I like my files compressed in camera, I don't feel the need to spend time concerting them after fact, and the RAW processing software I use won't store an adjusted preview in the DNG file, so what could otherwise be the single biggest advantage of DNG (and it's a *big* advantage, to be sure - no more complaining that other applications can't see your changes) - is moot for me. I'd consider converting it anyhow - and I used to, when shooting with the DS, since that was the only way to get compression. But the fact that working with DNG is noticeably slower meant that once I got a camera that compressed PEF, I stopped caring about DNG. Sidecar files are just not a big deal to me - they are basically handled completely automatically and transparently in my workflow.
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