PEF or DNG - which RAW format do you prefer?

marike6 said:

DNG on the K-30 and Ricoh GR is only 12-bit while PEF from the K-5, K-5IIs, and K-3 are full 14-bit RAWs. For me, the 14-bit files are by far more desirable. With my Nikon I always shoot 14-bit uncompressed.

DxOMark when they tested the K-30 talked about the possibility that the 12-bit DNG cost the K-30 around 1 EV vs the K-5 which uses the same exact Sony Exmor sensor as the K-30 but gets over 14 EV DR vs 13 EV for the K-30.

14-bit files should also provide better color depth at least in theory. Whether it's a big enough difference to matter. But since I take the time to shoot and process RAW, I'd rather shoot 14-bit uncompressed.

DNG in theory should work with more RAW converters, but that's a moot point because DNG in every implementation I've ever used, only a 12-bit RAW file instead of the usual, industry standard 14-bit RAW.

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1. DNG's can be any required depth, and although the K-x/K-r/K-30/K-50/K-500 cameras output both PEF's and DNG's with a 12-bit depth, the K-5 series, the K-3, and the 645D all output 14-bit depth for both their PEF's and DNG's. There is only a (slight) benefit to the 14-bit raw files for the K-5 and K-3 for ISO's below about 400; unfortunately we have no choice in the raw bit depth as Nikon shooter do so we could save several Megabytes of card space per raw image for higher ISO's. The Nikon uncompressed format has no real benefit as to image quality from either the loss-less and the "virtually loss-less" (slightly lossy) NEF format and the main trade-off is processing time and storage space requirements.
2. The sensors are not the same between the K-01, K-30, K-50, and K-500 in that they have different raw pixel dimensions and layout and those sensors can be scanned faster than the sensor from the K-5 series, which higher scanning frequency is likely the main reason for slightly less low ISO Dynamic Range (DR) than the K-5 series more than the lower bit depth.
3. Raw files with a 14-bit depth do indeed have somewhat more colour accuracy, but only if one pushes low ISO files by about four EV's or more. As I said, the raw compression has nothing to do with real image quality.
4. There is no industry standard 14-bit raw depth, just newer cameras are starting to more commonly use that depth or have it available, even some makes such as Canon that don't have enough DR to be able to effectively use it such that the least significant bits contain nothing except random (and non-random) noise and patterns. As I said, the DNG standard is not limited to 12-bit raw depth and can be any depth the camera manufacturer chooses to output; in the case of Adobe DNG conversions from proprietary formats, the original raw bit depth is preserved in the output DNG file, recorded as 16-bit depth of which the most significant two bits contain zeros in the case of 14 bit files. When these files are loss-lessly compressed, there is no wasted space due to the zeros as they are compressed away.

Leandros S said:

GordonBGood said:

newmikey said:

You can always convert a PEF to DNG but will never be able to convert a DNG to PEF.

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Oh, I think "never" is too strong a word; in fact, it is possible to convert a DNG back to a PEF or any other raw format other than one can never completely reconstruct the thumbnail or embedded JPEG preview if they were replaced in the proprietary to DNG conversion process or in later processing - these would be replaced by versions generated by the back conversion processing.

I had started a Java project to do this for Pentax DSLR's so that those who had converted their raw images to DNG's would be able to use Bibble/Corel AfterShot Pro, but ran out of time and have never completed it. However, I got far enough along to have it working within limits.

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Leandros S wrote:

Maybe you already have. If not, try it and see?

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Manituwa said:

Manituwa said:

The only PP software that has issues with DNG I use is after shot and this is because the original developer 'bibble labs' had problems with Adobe and so has not implented DNG support.

and o

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The latest version of AfterShot Pro (1.2.0.7) works fine with DNG from the K-01 and K-5IIs. Other models too perhaps. Did Corel also have issues with Adobe? Paint Shop Pro was quite slow to add support for DNG.

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Leandros S said:

Petroglyph said:

My point was LR 5.3 isn't supporting K3 PEFs yet unless I missed it.

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Yes, but the colour profile used to process the DNG isn't quite right yet, either (don't know which one it's actually using - probably sth completely generic). I suspect both of those things will arrive at the same time.

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Barry Pearson said:

Leandros S said:

Petroglyph said:

My point was LR 5.3 isn't supporting K3 PEFs yet unless I missed it.

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Yes, but the colour profile used to process the DNG isn't quite right yet, either (don't know which one it's actually using - probably sth completely generic). I suspect both of those things will arrive at the same time.

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When Adobe hasn't got its own colour profile, and isn't given one by the user, it will use the embedded profile in a DNG. This is put there by (say) the K-3 itself - it isn't "generic"(whatever that means!)

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GordonBGood said:

newmikey said:

You can always convert a PEF to DNG but will never be able to convert a DNG to PEF.

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Oh, I think "never" is too strong a word; in fact, it is possible to convert a DNG back to a PEF or any other raw format other than one can never completely reconstruct the thumbnail or embedded JPEG preview if they were replaced in the proprietary to DNG conversion process or in later processing - these would be replaced by versions generated by the back conversion processing.

I had started a Java project to do this for Pentax DSLR's so that those who had converted their raw images to DNG's would be able to use Bibble/Corel AfterShot Pro, but ran out of time and have never completed it. However, I got far enough along to have it working within limits.

Regards, GordonBGood

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Leandros S said:

Leandros S said:

Leandros S said:

Yes, but the colour profile used to process the DNG isn't quite right yet, either (don't know which one it's actually using - probably sth completely generic). I suspect both of those things will arrive at the same time.

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When Adobe hasn't got its own colour profile, and isn't given one by the user, it will use the embedded profile in a DNG. This is put there by (say) the K-3 itself - it isn't "generic"(whatever that means!)

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Well, it seems that Adobe's profiles are tuned differently than the embedded ones, b/c if you import a K-3 image through ACR and do the same with one from a K-5 II, same test scene, you end up with some surprisingly different colours, esp. in the reds. Try the IR test scene images for a bit of "fun"...

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