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05-25-2009, 12:42 AM   #1
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K-7 distortion & CA correcting?

Hi,

does anybody know if this corrections for DA & D-FA lenses are "real time"? I mean if I can set corrections in menu & every files (RAW & JPEG) will be affected or it is only choice if I'll develop image in camera for JPEG or TIFF output?

05-25-2009, 01:57 AM   #2
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If correction is turned on, it will be applied to JPEG-files directly when saved.
For RAW-files, the correction data is saved together with the file, but not applied until the RAW-file is being processed (developed). This is because RAW is an unprocessed, undeveloped image. It is against the RAW-idea to apply corrections to it.

Pentax latest version of PhotoLab can read the correction data from the RAW-file and apply to the image when processing and developing into JPEG or whatever.
05-25-2009, 03:30 AM   #3
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Hi,

I'm not sure I understood that completley. Does it that mean that the correction info will be embedded in the raw DNG as well so that for example LR will have the CA-settings altered when the file is read, or is it just pentax photolab that it will work for?

Thanks

Igor

PS. Sorry for jumping into a thread like this without introducing myself in the introduction page, but hopefully that will be some other time when I'm not in a hurry =).
05-25-2009, 04:21 AM   #4
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It's a good question. Does anyone who has a pre-production model confirm or deny this? Does the CA correction correct in RAW, or only JPG?

05-25-2009, 04:31 AM   #5
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QuoteOriginally posted by danic Quote
It's a good question. Does anyone who has a pre-production model confirm or deny this? Does the CA correction correct in RAW, or only JPG?
Roland has already answered that question. RAW is not altered but keeps that info. Only Jpeg is saved corrected. As for LR maybe with a plug-in feature that can handle the K-7 profile it will take that info and process.
05-25-2009, 04:36 AM   #6
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John C from Pentax said it applies to both RAW and JPEG, but takes a few seconds to process.
05-25-2009, 04:37 AM   #7
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QuoteOriginally posted by RuiC Quote
As for LR maybe with a plug-in feature that can handle the K-7 profile it will take that info and process.
Ok, thx. I hoped that the DNG format would support the CA-adjustment info so that info could be saved there by the camera and LR could read it without any extras (since Adobe has created both DNG and LR), but maybe it's not the case. But I'll still hope that's the case until proven otherwise =)
05-25-2009, 04:38 AM   #8
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QuoteOriginally posted by Igor123 Quote
I'm not sure I understood that completley. Does it that mean that the correction info will be embedded in the raw DNG as well so that for example LR will have the CA-settings altered when the file is read, or is it just pentax photolab that it will work for?
This is a very good question.

AFAIK (and my response is not meant to be affirmative!), the following holds true:

- Corrections applied in body for JPG (takes ~4s per image extra processing time).

- Corrections applied by PPL in raw processing.

- Corrections applied by Silkypix in raw processing (same raw converter). (*)

- Corrections applied by LR2 in raw processing. (*)
LR2 included a hidden corrections module late 2008 (upon pressure from Panasonic, it seems) and secretly applies corrections based on data written to the raw file. John C. from Pentax mentioned that he believes that LR treats the correction data as written by K-7. This is likely because Silkypix and LR expect the same kind of raw file meta data. Adobe's DNG converter applies the same corrections. Simple test: If the converted DNG files are 3x bigger, then the corrections had been applied.


All claims marked (*) are my own deductions and may prove false.


--
Source info:
It all can be deduced from this remark on Adobe web pages:
QuoteQuote:
There is an important exception in our DNG file handling for the Panasonic DMC LX3, Panasonic DMC FX150, Panasonic DMC FZ28, Panasonic DMC-G1 and Leica D-LUX 4. For those choosing to convert these native, proprietary files to the DNG file format, a linear DNG format is the only conversion option available at this time. A linear DNG file has gone through a demosaic process that converts a single mosaic layer of red, green and blue channel information into three distinct layers, one for each channel. The resulting linear DNG file is approximately three times the size of a mosaic DNG file or the original proprietary file format.

This exception is a temporary solution to ensure that Panasonic and Leica's intended image rendering from their proprietary raw file format is applied to an image when converted DNG files are viewed in third party software titles. The same image rendering process is applied automatically in Camera Raw and in Lightroom when viewing the original proprietary raw file format.

In a future release Adobe plans to update the DNG specification to include an option to embed metadata-based representations of the lens compensations in the DNG file, allowing a mosaic DNG conversion. In the interim Adobe recommends only converting these files to DNG to allow compatibility with third party raw converters, previous versions of the Camera Raw plug-in or previous versions of Lightroom.
[source: http://www.adobe.com/products/photoshop/cameraraw.html]

The remark only applies to Panasonic and what is meant are the vignetting, CA and lens distortion info. But it seems that all files which carry the corresponding information are treated alike.


Last edited by falconeye; 05-25-2009 at 04:46 AM.
05-25-2009, 01:15 PM   #9
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QuoteOriginally posted by Igor123 Quote
I'm not sure I understood that completley. Does it that mean that the correction info will be embedded in the raw DNG as well so that for example LR will have the CA-settings altered when the file is read, or is it just pentax photolab that it will work for?
The correction data is saved with Pentax PEF-files. I don't know if it is also saved with DNG-files. I believe if DNG has support for this data, then it will also be saved. I know to little about the DNG-standard to answer that question.
05-25-2009, 01:18 PM   #10
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QuoteOriginally posted by danic Quote
It's a good question. Does anyone who has a pre-production model confirm or deny this? Does the CA correction correct in RAW, or only JPG?
It can't be confirmed by those with a pre-production model of the K-7, since one needs the new version of PhotoLab software to read this RAW-file and get it corrected.

The correction data is not applied to the image in the RAW, because if it were it wouldn't be a RAW-file. RAW-files are the unprocessed image data directly from the sensor. Then the RAW data also contains extra information, which can be used by the converter. This data does not change the image in the RAW-file by itself, this information needs to be read by a RAW-converter - such as Pentax PhotoLab - and then applied by the RAW-converter to the RAW-image when it creates a final image (JPEG or TIFF) from the RAW-file.
05-25-2009, 01:23 PM   #11
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QuoteOriginally posted by falconeye Quote
- Corrections applied in body for JPG (takes ~4s per image extra processing time).
Yes.

QuoteQuote:
- Corrections applied by PPL in raw processing.
Yes.

QuoteQuote:
- Corrections applied by Silkypix in raw processing (same raw converter). (*)
No. Silkypix is not the same RAW-converter as the Pentax PhotoLab.
Pentax PhotoLab uses the basic image processing engine from Silkypix, that translates RAW-data into JPEG or TIFF. But to this engine, Pentax can add whatever functionality they want. So just because Pentax PhotoLab has automatic distorsion and CA correction for the K-7 does not mean that the Silkypix Developer Studio also has it.

QuoteQuote:
- Corrections applied by LR2 in raw processing. (*)
LR2 included a hidden corrections module late 2008 (upon pressure from Panasonic, it seems) and secretly applies corrections based on data written to the raw file. John C. from Pentax mentioned that he believes that LR treats the correction data as written by K-7. This is likely because Silkypix and LR expect the same kind of raw file meta data.
But PhotoLab is not Silkypix!
And PhotoLab reads the Pentax Electronic File, which isn't the same as DNG.
Lightroom 2 has currently no support for the PEF-files from the Pentax K-7.
05-25-2009, 02:33 PM   #12
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QuoteOriginally posted by RMabo Quote
Pentax PhotoLab uses the basic image processing engine from Silkypix, that translates RAW-data into JPEG or TIFF.
[...]
But PhotoLab is not Silkypix!
And PhotoLab reads the Pentax Electronic File, which isn't the same as DNG.
Lightroom 2 has currently no support for the PEF-files from the Pentax K-7.
Well, let me explain a few intermediate steps of my reasoning then ...

It is the "basic image processing engine from Silkypix" which does the correction. At least it was said that Silkypix behaves the same as LR2 for Panasonic raw files. i.e., it is automatic and cannot be switched off.

PhotoLab reads PEF and Pentax DNG. Obviously, DNG now incorporates correction meta data, an extension to the DNG format planned by Adobe. And the Silkypix engine can read it. Pentax and Adobe cooperate for the DNG format, Silkypix must be involved as well. So, if John. C says he believes that LR can do it as well, it is only logical to assume that LR, in its update to support K-7, will support DNG and PEF lens correction metadata. Something they work upon for Panasonic anyway.
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