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05-21-2016, 11:24 AM   #16
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QuoteOriginally posted by Oakland Rob Quote
So even if you have it "on" in the camera it does nothing viz a viz the RAW files, although it might affect the embedded JPEG preview.
That seems to be correct. I loaded the DNG of PentaxForums' PS sample shot in a hex editor and saw that it was basically 4 Image File Directories holding 4 RAW sensor data. The overall structure was almost identical to one of my K5 DNGs, minus the extra 3 IFDs. I'm not sure if MC was on or off in the sample shot, but I didn't find any means for the body to communicate regions it detected motion to the RAW processor, such as a mask. If MC was on in the sample shot, this suggests that its purely up to the raw processor, either the built in JPEG engine or computer software, to detect and correct the motion.

Since motion correction seems to be a unique feature, there didn't seem to be an entry for it in the EXIF directory in the DNG file, although I didn't check to see if Pentax had overloaded an older/obsolete EXIF entry type. There is also a large block of data in the DNG that is reserved for manufacturer specific private data that I haven't tried to parse, so it's possible I missed something. In the end, if motion detection and correction of PS RAW is done entirely in software, it's likely that the MC setting has minimal to no impact to the RAW data.

05-21-2016, 02:10 PM   #17
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QuoteOriginally posted by sprint113 Quote
That seems to be correct. I loaded the DNG of PentaxForums' PS sample shot in a hex editor and saw that it was basically 4 Image File Directories holding 4 RAW sensor data. The overall structure was almost identical to one of my K5 DNGs, minus the extra 3 IFDs. I'm not sure if MC was on or off in the sample shot, but I didn't find any means for the body to communicate regions it detected motion to the RAW processor, such as a mask. If MC was on in the sample shot, this suggests that its purely up to the raw processor, either the built in JPEG engine or computer software, to detect and correct the motion.

Since motion correction seems to be a unique feature, there didn't seem to be an entry for it in the EXIF directory in the DNG file, although I didn't check to see if Pentax had overloaded an older/obsolete EXIF entry type. There is also a large block of data in the DNG that is reserved for manufacturer specific private data that I haven't tried to parse, so it's possible I missed something. In the end, if motion detection and correction of PS RAW is done entirely in software, it's likely that the MC setting has minimal to no impact to the RAW data.
Very interesting!!!

Well, if MC setting has "minimal to no impact to the RAW data", why did Pentax include a motion correction on/off control on the K1 - for JPGs?
05-21-2016, 02:26 PM - 1 Like   #18
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QuoteOriginally posted by Fenwoodian Quote
Very interesting!!!

Well, if MC setting has "minimal to no impact to the RAW data", why did Pentax include a motion correction on/off control on the K1 - for JPGs?
Yes, just for JPEGs, no different to lens corrections, for example, which is a setting that has no affect on RAW files.

Given the algorithms used, I suspect turning off MC in camera may save precious seconds while the camera processes the picture. If you are going to process the shots with PDCU you may as well leave it off. The algorithms in PDCU will be the same, if not better given the extra processing power a PC would have over the camera.

For us K-3II owners that is a bit academic, but I think it is really good that Pentax didn't limit new processing features of PDCU to just the K-1. I'm now going to have to start considering the use of PS more often!
05-21-2016, 03:51 PM   #19
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QuoteOriginally posted by GodsPetMonkey Quote
Yes, just for JPEGs, no different to lens corrections, for example, which is a setting that has no affect on RAW files.

Given the algorithms used, I suspect turning off MC in camera may save precious seconds while the camera processes the picture. If you are going to process the shots with PDCU you may as well leave it off. The algorithms in PDCU will be the same, if not better given the extra processing power a PC would have over the camera.

For us K-3II owners that is a bit academic, but I think it is really good that Pentax didn't limit new processing features of PDCU to just the K-1. I'm now going to have to start considering the use of PS more often!

Thanks so much for the answer! Very clearly said, and you obviously have considerable knowledge in this area.

I see that you have not posted much here. Are you new here? I for one look forward to reading more of your posts in the future!

05-21-2016, 05:28 PM   #20
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QuoteOriginally posted by sprint113 Quote
Since motion correction seems to be a unique feature, there didn't seem to be an entry for it in the EXIF directory in the DNG file, although I didn't check to see if Pentax had overloaded an older/obsolete EXIF entry type.
Makernotes is where you would look and it won't have a friendly label.


Steve
05-21-2016, 05:57 PM   #21
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QuoteOriginally posted by Fenwoodian Quote
why did Pentax include a motion correction on/off control on the K1 - for JPGs?
Near as I can tell, at very least it sets a flag in the metadata for the the RAW processor to do some extra magic. PDCU 5.5.1 has three options for pixel shift:
  • "Camera setting"
  • "Off"
  • "On (Motion Correction Off)"
  • "On (Motion Correction On)"
The most recent version of ExifTool lists a Pentax-specific makernotes tag, PixelShiftInfo/PixelShiftResolution* of type int8u with known values of 0 and 1. I suspect that Pentax added a third value for the K-1 such that the mapping goes:
  • 0 = Off
  • 1 = On (MC on)
  • 2 = On (MC off)
Plain old PS images in PDCU 5.5.1 show "Pixel Shift: On (Motion Correction On)" in the "Shooting Information" box. If "Camera settings" is used for processing, the results are the same as for On (MC on). I suspect there is more to the story and that a certain amount of motion correction has been being done on the K-3II by default both in-camera and with earlier versions of PDCU. I have hard evidence beyond what I posted earlier in this thread, but need to figure out a good way to present it. I would also like to find two K-1 PS DNG (MC on, MC off) for comparison.


Steve

* The names of makernotes tags in ExifTool are semi-arbitrary and reflect the developer's best guess or deduction as to meaning of both tag and values.
05-27-2016, 12:14 AM   #22
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QuoteOriginally posted by stevebrot Quote
Plain old PS images in PDCU 5.5.1 show "Pixel Shift: On (Motion Correction On)" in the "Shooting Information" box. If "Camera settings" is used for processing, the results are the same as for On (MC on). I suspect there is more to the story and that a certain amount of motion correction has been being done on the K-3II by default both in-camera and with earlier versions of PDCU. I have hard evidence beyond what I posted earlier in this thread, but need to figure out a good way to present it. I would also like to find two K-1 PS DNG (MC on, MC off) for comparison.
I am now pretty certain that the K-3II does do motion correction in camera. If I compare the OOC JPEG to what PDCU produces both with MC on and MC off it is pretty clear that some of the motion is being eradicated for the in camera JPEG. In fact, most of my test JPEGs are as good as what PDCU does, so the algorithm isn't too shabby! Given there has been no firmware upgrades for the K-3II this motion correction must have been there all along. The odd thing in my mind is why Pentax hasn't made any noise about it - they have trumpeted the MC for the K-1 - were they not as confident about the technology when the K-3II launched?

QuoteOriginally posted by Fenwoodian Quote
Thanks so much for the answer! Very clearly said, and you obviously have considerable knowledge in this area.
Thanks. I wouldn't say I am particularly knowledgeable about this, but I have had a play with PS, even more now with the updated versions of PDCU. Glad that I look like I know what I am doing though!
05-27-2016, 01:50 AM   #23
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Just so long as you understand Motion Correction won't work on fine detail such as leaves, grass or hair. The reason being it is difficult to detect motion in details like these. It will work with moving water (e.g. waterfalls) as long as you are not looking for detail like drops of spray and want the wispy white flows. There is no detail in that.

Simple test to see if the K3ii does motion correction. Take a Pixel Shift photo of a scene with easily recognizable moving objects such as automobiles or ice skaters moving across the scene, e.g. left to right. Process in PDU 5.5.1 with MC off. You should get 3-4 ghost images of the moving object(s) but not in the static portions of the scene. Process with MC on. You should only have one image of the moving object(s) but not with the amount of detail as the static portions of the scene.

08-02-2016, 02:48 PM   #24
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This news definitely puts the II in contention for my attention
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