RAW of PEF?


myrdinn

Link Posted 21/07/2007 - 20:36
Silkypix does need a powerful machine. However, in use it is pretty quick because you can deal with pictures in batches, then do something else while it's processing them.

G[/quote]

Indeed Silkypix needs a powerful machine. But the Pentax Laboratory doesn't need much power, so you can use that. It doesn't have as many options ls the real Silky but for most cases it will do.

George Lazarette

Link Posted 21/07/2007 - 20:38
myrdinn wrote:
Silkypix does need a powerful machine. However, in use it is pretty quick because you can deal with pictures in batches, then do something else while it's processing them.

Indeed Silkypix needs a powerful machine. But the Pentax Laboratory doesn't need much power, so you can use that. It doesn't have as many options ls the real Silky but for most cases it will do.

It provides the same quality, I believe, but only a fraction of the facilities, and in particular it lacks batch processing. There really is no comparison between them.

G
Keywords: Charming, polite, and generally agreeable.

Snadalholme

Link Posted 13/08/2007 - 17:02
Re PEF vs DNG. I swapped tp PEF recently and only by chance found out that PEF is 8 bit, whereas DNG is 16 bit. The reason I believe this to be true is that I use PS Elements 4, using the Adobe RAW processor and quite a lot of the features of Elements 4 can't cope with 16 bit. It was only when I did a bit of cloning to remove some flare that I realised the file was 8 bit. Yes, I know from some experimentation that Silkypix produces more detailed images than Adobe RAW, but this is another learning curve that I'm not quite ready for and as I save all my digital negatives, I can always go back and re-process the really special shots. It may be that the Adobe RAW processor converts to 8 bit, but as it doesn't do this for DNG files, it's odd if it does it for PEFs.

Is this the reason why PEF files are smaller? I'm sure someone will correct me if I'm wrong!

Stuart

George Lazarette

Link Posted 13/08/2007 - 20:45
PEF files are 12-bit. Even if DNG files are 16-bit, the K10D will only be supplying 12 bits of data.

G
Keywords: Charming, polite, and generally agreeable.

Snadalholme

Link Posted 13/08/2007 - 21:27
Thanks George for that explanation - I knew someone would know the facts. it doesn't explain why Elements 4 sees a 12 bit DNG file as 16 bit and 12 bit PEF file as 8 bit. Or, putting it slightly differently, why Elements 4 has full facilities processing PEF files but limited facilities processing DNG files. I guess this is an Adobe question rather than a Pentax one, but it's strange.

Stuart

photog 73

Link Posted 26/08/2007 - 11:13
I have used both PEF and DNG. I have not noticed any problem shooting bursts of 5 plus images in PEF or in fact DNG either. I feel that the ability to save about 380+ PEF filesd to 4GB against 240-250 is well worth the slight extra save time.

I have used both DNG and PEF extensively. So far I have shot 4-5000 from K-10D. Both give excellent results processed in PsCs3 Using Bridge 2 and Adobe camera raw 4.1.

My Sigma 10-20 gives breathtaking brilliance - simply marvelous quality. Ny prints are better than anything I did in the old days (Hasselblad, Zeiss lenses, SuperChromega enlarger with Schneider or ElNikkor lenses of the Durst M5-8 daylight printer. State of the art in the 1970's)

the K-10D is marvelous value for money and can hold its own in (almost) and company.

photog 73
Reformed large format photographer

Rodger Fooks

Link Posted 26/08/2007 - 11:45
I notice that CS3 defaults to 8Bit in conversion of PEF and DNG files but this can be changed to 16bit although the file (DNG or PEF) will only supply 12 bit.

What I didn't realise is that if you shoot JPG the camera uses 8bit.

Another good reason to keep to raw processing
Old wood best to burn, old wine to drink, old friends to trust, and old authors to read.

photog 73

Link Posted 26/08/2007 - 12:14
Rodger Fooks wrote:
I notice that CS3 defaults to 8Bit in conversion of PEF and DNG files but this can be changed to 16bit although the file (DNG or PEF) will only supply 12 bit.

What I didn't realise is that if you shoot JPG the camera uses 8bit.

Another good reason to keep to raw processing

Yes JPG is 8bit. If you set the camera to AdogeRGB and set the save options in Bridge / ACR to 16bit you can save in TIF or PSD. You can then process the images as much as necessary without loss of quality or the banding that comes with JPG.
photog 73
Reformed large format photographer

photog 73

Link Posted 03/09/2007 - 10:26
Snadalholme wrote:
Re PEF vs DNG. I swapped tp PEF recently and only by chance found out that PEF is 8 bit, whereas DNG is 16 bit. The reason I believe this to be true is that I use PS Elements 4, using the Adobe RAW processor and quite a lot of the features of Elements 4 can't cope with 16 bit. It was only when I did a bit of cloning to remove some flare that I realised the file was 8 bit. Yes, I know from some experimentation that Silkypix produces more detailed images than Adobe RAW, but this is another learning curve that I'm not quite ready for and as I save all my digital negatives, I can always go back and re-process the really special shots. It may be that the Adobe RAW processor converts to 8 bit, but as it doesn't do this for DNG files, it's odd if it does it for PEFs.

Is this the reason why PEF files are smaller? I'm sure someone will correct me if I'm wrong!

Stuart

You are wrong as to the PEF file format. PEF is the pentax native format. The file is smaller because the PEF uses Lossless compression. It is still 16 bit. To the best of my knowledge all of the RAW formats use 16 bit processing which is why they allow 2-3 stops and even more exposure latitude when processed in Photoshop and similar. My experience processing both PEF and DNG is that the options desired are preset in ACR (Adobe camera raw - a plugin that can be downloaded from Adobe), both formats are then handled in the same way. If you are using Adobe DNG converter (free from Adobe) you may have chosen an option that makes the conversion.

As re the pros and cons of Adobe CS3, Silkypix etc the main difference will be traceable the the skill level you have in the use of your preferred application.

Ron
Reformed large format photographer

Clarky

Link Posted 03/09/2007 - 10:59
Hey fellow Aussie Photog 73
Location: Brisbane, Qieensland, Australia
Whats the go with the (i) instead of the (u) in Queensland
Camera:|K-7|
Pentax Lenses:|DA12-24/f4 ED AL|DA35Ltd Macro|FA31Ltd|FA77Ltd|FA50/1.4|F70-210|FA20-35 f4/AL|A*200/f4 Macro ED|A50/1.7|A50 Macro f2.8|1.7xAF adapter|
Voigtlander|125/f2.5SL Macro APO Lanthar|
Sigma Lenses:|EX DG 100-300 f4|2X & 1.4X TC|
Flashes:|AF540FGZx2|RingFlash AF160FC|

George Lazarette

Link Posted 03/09/2007 - 11:07
photog 73 wrote:
Snadalholme wrote:
Re PEF vs DNG. I swapped tp PEF recently and only by chance found out that PEF is 8 bit, whereas DNG is 16 bit.
Stuart

You are wrong as to the PEF file format. PEF is the pentax native format. The file is smaller because the PEF uses Lossless compression. It is still 16 bit.
Ron

And you are also wrong. PEF is 12-bit.

G
Keywords: Charming, polite, and generally agreeable.

MattMatic

Link Posted 03/09/2007 - 11:12
Actually, the RAW format is 12-bit.
The *ist-D stored the 12-bit data inside a 16-bit space (wasting 4-bits which were always zero).
The *ist-Ds and other 6Mp cameras used the 12-bits as-is and packed them - hence their PEF formats were smaller than the ist-D.
The K10D added lossless Huffman encoding to squeeze the filesize down more (it could that because it has a much faster CPU compared to the other cameras).

The RAW converter takes the 12-bits per photo-site (not exact a pixel), applies some serious maths (because the photo-sites are arranged in sets of four: green, red, green, blue) to reconstruct the full image and then:

* It can output to 8-bit JPG (which incidentally throws a lot of the blue channel information away)
* It can output to 8-bit TIFF (which is better than JPG because you have 256 level of each of Red, Green and Blue available).
* It can output to 16-bit TIFF

In the first two cases, Photoshop (or Elements) will load the image into the PC and allow editing in 8-bit image space.

In the second case, Photoshop provides a reduced feature set to allow editing in 16-bit space.

To be honest, unless you are doing some really, really serious image manipulation you will be just absolutely fine with an 8-bit image

If you have big problems with dynamic range and the like you are better off learning to use the RAW converter more, and possibly to output two images from the one RAW file and blend in Photoshop.

Hope that's not too confusing
Matt

EDIT: Crossed in the ether with George
http://www.mattmatic.co.uk
(For gallery, tips and links)

photog 73

Link Posted 03/09/2007 - 11:54
MattMatic wrote:
Actually, the RAW format is 12-bit.
The *ist-D stored the 12-bit data inside a 16-bit space (wasting 4-bits which were always zero).

Of course you are right.
Ron
Reformed large format photographer

viewfinder

Link Posted 07/09/2007 - 09:17
Is it correct that K100 will only capture using the Pentax version of RAW, ie so called 'PEF', and DNG is NOT available with this camera?

I have searched 'Self Help For Insomniacs',..aka the 'Operating manual' but to no obvious avail.

namstoop

Link Posted 07/09/2007 - 09:54
viewfinder wrote:
Is it correct that K100 will only capture using the Pentax version of RAW, ie so called 'PEF', and DNG is NOT available with this camera?

I have searched 'Self Help For Insomniacs',..aka the 'Operating manual' but to no obvious avail.

Yes, K100 shoots only .pef.
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