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11-12-2019, 12:45 AM   #16
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QuoteOriginally posted by acoufap Quote
You‘re a kind of funny guy! - Put the camera on a tripod and capture three shots of the exact same scenery in FF, Square and APSC mode. Develop it without any manual or automatic changes in LR and generate jpg‘s for each with same settings - what are the sizes of the jpg files?
No im too lazy.

11-12-2019, 12:58 AM - 1 Like   #17
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Corel PaintShop Pro doesn't show the square mode too...
11-18-2019, 04:00 AM   #18
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QuoteOriginally posted by acoufap Quote
As long as there are no sensors used in cameras that support more flexible crop area pixel read-out, we won‘t see raw level crops with higher speed read-out, less memory consumption etc. - unfortunately.
Storing only the data of the 1:1 content isn't predicated on special sensor read-out support.

In other words, while a sensor read-out speed increase would not be possible without a dedicated read-out mode, it is very much possible to only write the 1:1 content to the card.

I'm wondering whether a conversion to a DNG file, e.g., using the Adobe DNG converter and a Pentax PEF file as input, could achieve the file size reduction some are after. The question is whether the resultant DNG file will still contain all of the RAW data and the mask specification, or just the relevant RAW data.
11-18-2019, 10:57 AM   #19
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QuoteOriginally posted by Class A Quote
Storing only the data of the 1:1 content isn't predicated on special sensor read-out support.

In other words, while a sensor read-out speed increase would not be possible without a dedicated read-out mode, it is very much possible to only write the 1:1 content to the card.

I'm wondering whether a conversion to a DNG file, e.g., using the Adobe DNG converter and a Pentax PEF file as input, could achieve the file size reduction some are after. The question is whether the resultant DNG file will still contain all of the RAW data and the mask specification, or just the relevant RAW data.
DNG is only a standardized container format where the camera puts in the sensor data and it‘s icc camera profile and some additional data. DNG out of camera is a native raw format. The only difference to a camera manufacturer specified raw container like pef is that the data model specification originally comes from Adobe.

If you use the Adobe DNG converter to archive your raw captures of whatever format it is recommended to embed the whole native raw file. And if not, a mapping is done from one data model to the other. That‘s at least what I remember.* By the way - the mapping can yield to some raw file data loss - remember what data is embedded. You can explore the whole data using exiftool.

So in any case I can‘t imagine that there’s any single sensor cell data reading involved. Also remember: a rgb image where you could identify a single pixel by x- and y-coordinate you only get by raw data conversion based on the bayer filter where pixels are determined, So the Adobe DNG converter simply won’t cut out a square or any other rectangle from the sensor data. I am convinced any DNG container will keep the whole sensor data of raw files.

But you can do your own experiments and prove me to be wrong. I just think it‘s a waste of time. ;-)

*Years ago I used the Adobe DNG Converter for converting my cr2 files of the Canon Powershot G10 to get a standardized raw format and I did it based on some information from different sources.


Last edited by acoufap; 11-18-2019 at 11:26 AM.
11-18-2019, 12:22 PM   #20
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QuoteOriginally posted by acoufap Quote
DNG is only a standardized container format where the camera puts in the sensor data and it‘s icc camera profile and some additional data. DNG out of camera is a native raw format. The only difference to a camera manufacturer specified raw container like pef is that the data model specification originally comes from Adobe.

If you use the Adobe DNG converter to archive your raw captures of whatever format it is recommended to embed the whole native raw file. And if not, a mapping is done from one data model to the other. That‘s at least what I remember.* By the way - the mapping can yield to some raw file data loss - remember what data is embedded. You can explore the whole data using exiftool.

So in any case I can‘t imagine that there’s any single sensor cell data reading involved. Also remember: a rgb image where you could identify a single pixel by x- and y-coordinate you only get by raw data conversion based on the bayer filter where pixels are determined, So the Adobe DNG converter simply won’t cut out a square or any other rectangle from the sensor data. I am convinced any DNG container will keep the whole sensor data of raw files.

But you can do your own experiments and prove me to be wrong. I just think it‘s a waste of time. ;-)

*Years ago I used the Adobe DNG Converter for converting my cr2 files of the Canon Powershot G10 to get a standardized raw format and I did it based on some information from different sources.
What I don't understand is that crop mode for APS-C lenses on the K-1 does actually give us smaller RAW files. So there does seem to be a way to shoot RAW, use less of the sensor than it's native 35mm size and get smaller RAW files.
I recall the 1:1 being a firmware update, the fact that it's just a mask suggests to me Pentax could make it a proper crop RAW like the APS-C mode but chose not to, because it was more difficult etc.
11-18-2019, 01:07 PM   #21
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QuoteOriginally posted by BruceBanner Quote
What I don't understand is that crop mode for APS-C lenses on the K-1 does actually give us smaller RAW files. So there does seem to be a way to shoot RAW, use less of the sensor than it's native 35mm size and get smaller RAW files.
I recall the 1:1 being a firmware update, the fact that it's just a mask suggests to me Pentax could make it a proper crop RAW like the APS-C mode but chose not to, because it was more difficult etc.
My notion is that the sensor supports two read-out modes: FF and APSC.

Software controls which mode is used - the user interface for choosing the mode is based on menu item setting (software) and dials (hardware).

For the optical viewfinder we really have three controllable settings based on the OVF overlay offerings (red frames). The triggering of the third setting - Square Mode - we got with a firmware update. initially it was not possible to choose it by menu or dial. Of course we also got live view support for this. But this is much easier to offer because it's simply "only" software-controlled.

Ricoh decided to give us, what the K-1 hardware supports. So they gave us the opportunity to select the Square Frame overlay but had to compromise sensor readout using FF read-out and adding some masking data - that's not used by some raw converters.
11-18-2019, 08:27 PM   #22
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I seem to recall that the square format was on the first prototypes. But of course missing from the full release. Brought back with firmware update.
11-19-2019, 03:53 AM   #23
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QuoteOriginally posted by acoufap Quote
DNG is only a standardized container format where the camera puts in the sensor data and it‘s icc camera profile and some additional data.
Not sure what any of that has to do with what I wrote.

QuoteOriginally posted by acoufap Quote
So the Adobe DNG converter simply won’t cut out a square or any other rectangle from the sensor data.
Well, it does omit the masked pixel data from original PEF files, for instance.
(Most people don't need that masked pixel data anyhow, but it part of the original data that is filtered out by the Adobe DNG converter.)

If that kind of data reduction occurs, I think it is plausible that only visible pixels (those inside the 1:1 mask) could be actually stored in the DNG file (still not demosaiced, of course).

QuoteOriginally posted by acoufap Quote
But you can do your own experiments and prove me to be wrong.
I won't be doing any experiment myself because I shot about three square images with my K-1, mainly for testing purposes.

I just thought I mention the potential for someone who shoots a lot of 1:1 images and is keen on saving data to check whether the Adobe DNG converter may do the trick for them. TBH, I doubt the converter would go through the trouble of filtering the data but it is not entirely inconceivable that it does.

12-01-2019, 01:38 PM   #24
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QuoteOriginally posted by BruceBanner Quote
What I don't understand is that crop mode for APS-C lenses on the K-1 does actually give us smaller RAW files. So there does seem to be a way to shoot RAW, use less of the sensor than it's native 35mm size and get smaller RAW files.
I recall the 1:1 being a firmware update, the fact that it's just a mask suggests to me Pentax could make it a proper crop RAW like the APS-C mode but chose not to, because it was more difficult etc.
It looks as if the APS-C readout probably only grabs the middle 2/3 of the sensor lines - this is borne out by the highest frame rate being about 3/2 of the FF frame rate, 6.5fps vs 4.4fps, assuming the top speed is limited by sensor readout rate. If all the data were then saved as a RAW you'd get a rather weird 9:4 aspect ratio, so the outer 1/3 of the resulting data are discarded before saving the RAW (or JPEG). It's undoubtedly possible to do a similar thing for the 1:1 crop, but Pentax clearly chose not to do so for some reason. Maybe they think 6.5fps with a 1:1 aspect ratio is a rather niche market...

Cheers

Jonathan
12-01-2019, 02:10 PM   #25
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QuoteOriginally posted by h4yn0nnym0u5e Quote
It looks as if the APS-C readout probably only grabs the middle 2/3 of the sensor lines - this is borne out by the highest frame rate being about 3/2 of the FF frame rate, 6.5fps vs 4.4fps, assuming the top speed is limited by sensor readout rate. If all the data were then saved as a RAW you'd get a rather weird 9:4 aspect ratio, so the outer 1/3 of the resulting data are discarded before saving the RAW (or JPEG). It's undoubtedly possible to do a similar thing for the 1:1 crop, but Pentax clearly chose not to do so for some reason. Maybe they think 6.5fps with a 1:1 aspect ratio is a rather niche market...

Cheers

Jonathan
That's a good point, probably is, but I really doubt they thought that hard about the implementation and just took the easiest method. Now if they could provide 6x7, 4x3, 5x7 crop modes as well that would be neat
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