Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
08-02-2016, 05:04 PM - 1 Like   #1576
Senior Member




Join Date: May 2009
Location: Fort Lauderdale, FL
Photos: Gallery
Posts: 212
QuoteOriginally posted by Nicolas06 Quote
More, you don't especially need pixel shift to achieve theses results or even better.

Dynamic range, all camera I think have a HDR mode anyway that allow for much more dynamic range than what pixel shift allow, this work handled even. At worst shoot 3 or 5 exposure and you can get 4 or 8 EV more of dynamic range. That much more that pixel shift provide.
HDR mode does not actually change the dynamic range of an image per se, rather it gives the appearance of a higher dynamic range by mimicking within the picture what our brain does automatically. It makes the shadows not so shadowy (more exposure) so we can see details and the highlights not so highlighty (less exposure) so we can see more details but still, only 14-bit RAWs and 8-bit JPEGs.

QuoteOriginally posted by Nicolas06 Quote
For Color deph and noise, nothing prevent you to take 4 pictures (or 32) on your tripod and stack them for improved quality. People have been doing that for astro shots for years. While it is not as automated, any camera firmware could be updated for it. And because there no limit to number of photos, there no limit to the noise reduction and improved color deph.
Again, no improvement here in colour depth, only in noise reduction. And, yes, it is automated in Pentax cameras such as the K-3 and others with interval shooting and composite mode (and AstroTracer™).

QuoteOriginally posted by Nicolas06 Quote
Do a panorama, and you can scale the resolution without limit. Some people have produced gigapixels photographs this way.
True but this is not about gaining megapixels. A 36mp image before PS is still a 36mp image after PS. Pentax pixel shift is about automated improved details and colour accuracy of a 36mp image (or 24mp in the case of the K-3 II). But pixel shift the way Sony does it, is somewhat like this. This method is superior to what Sony does but Sony's method is easier than this.

QuoteOriginally posted by Nicolas06 Quote
I agree that for some case pixel shift is simpler/easier and provide nice results, but this is not a game changer. This is just a feature like many others.
Yeah, right. Like a pentaprism for eye-level viewing or auto focus, or programmed mode or SR or SMC or round aperture blades or oil resistant coating or trailing curtain sync or HSS or TTL or OTF metering or any other non-game-changing feature because it is just a feature like any other feature. Every innovation is a game changer because it introduces to the game a new rule which was not there before.

None of what you described as being what we had already is what we have now. Pixel shift, the way Pentax does it anyway, is a game changer in so many regards and it does things that no current technique can reproduce. [EDIT] To clarify, the Foveon sensor actually changed the game this way before. This is really not that new but it does it at higher resolution with lower noise, better low-light response and less cost per pixel. To be fair, Foveon were the leaders here.


Last edited by Logics; 08-02-2016 at 05:46 PM. Reason: Mentioned the Foveon as being first to market in this area.
08-02-2016, 07:49 PM - 1 Like   #1577
Loyal Site Supporter
Loyal Site Supporter




Join Date: Mar 2009
Location: Gladys, Virginia
Photos: Gallery
Posts: 27,572
QuoteOriginally posted by Nicolas06 Quote
Game changer is something that will heavilly change the market, how people use their camera, approach photography as a whole. This is disruptive product.

First iphone was a game changer it redefined the whole industry and now 3/4 of all the phones sold are basically iphones clones. Android was game changer because it allowed to get iphones clones for $100.

In photography, smartphones were maybe the biggest change we have seen since digital but we also had seen quite big change that can be arguably a game changer: CMOS vs CCD, cameras with great video or mirrorless bodies with EVF. That changes that shaped the market.

Pixel shift is just a feature among the hundred other features each camera has. Is it far better than a 50 iso setting? Is it better than a high burst rate or better OOC Jpegs? This will depend of each user but this isn't huge. Give a D810 or a K1 with the equivalent lenses to a good photographer he'll give you quite similar photographs from both. The biggest difference is the mount with the associated echosystem.
None of these things will change the market as a whole -- not iso 50, not pixel shift. If that is the benchmark, then full frame and APS-C cameras are mostly failures. People are looking at the whole package, though, not an individual feature when they choose a camera and the pixel shift is a nice feature to have.

Looking at the comparison of the DXO One camera versus the Super Raw it features, you can see the sort of improvement in high iso performance, color depth and dynamic range one can see with it. On the other hand, the difference between iso 100 and iso 50 on the D810 is about 0.4 EV of dynamic range. Significantly less, then the bump from having pixel shift.

Anyway, as I said above, it is one feature that the k-1 offers that isn't widely available from other manufacturers. If you shoot much landscape or macro photography, it could be useful.
08-02-2016, 10:51 PM   #1578
Veteran Member




Join Date: Nov 2013
Posts: 4,854
QuoteOriginally posted by Logics Quote
HDR mode does not actually change the dynamic range of an image per se, rather it gives the appearance of a higher dynamic range by mimicking within the picture what our brain does automatically. It makes the shadows not so shadowy (more exposure) so we can see details and the highlights not so highlighty (less exposure) so we can see more details but still, only 14-bit RAWs and 8-bit JPEGs.
Let's no mix up things. Shooting several exposure of the same scene give you drastically more dynamic range. If you have 5 exposures separated by 2EV each, you gain 8EV. You can't store this information in a single raw/jpeg but a standard exist for 32 bit per pixel HDR files instead of 8bit jpeg or 12,14 or 16 bit raws. Pixel shift keep 14 bit raws.

Whatever the technique, standard raws or pixel shift or HDR once you recorded the information the issue is what to do with it as prints 5-8EV and screen 8-10 EV with an upcoming standard for 12EV but anyway you export the final image as JPEG that is made for 8-9EV of dynamic range with the proper gamma curves.

You can push shadows, tone down the highlight on your raw. Or you can apply a tone mapping curve... But the final product still limited to 8-9EV anyway. You use trick to stay in that range and give the impression of additionnal dynamic range and use the defficiancies of human vision to trick it.

QuoteOriginally posted by Logics Quote
Again, no improvement here in colour depth, only in noise reduction. And, yes, it is automated in Pentax cameras such as the K-3 and others with interval shooting and composite mode (and AstroTracer™).
Shooting several pictures and averaging them reduce noise and increase color deph. This the same idea as of using a different iso. Take a longer exposure for increased quality. Taking 2 pictures of the same shutter speed increase exposure time by a factor of 2 and taking 4 by a factor of 4.

You can try for yourself, take a high iso setting with noise (say 6400 iso) on that K3 or K1, stack 64 pictures and see how the noise and color deph reduced.

QuoteOriginally posted by Logics Quote
True but this is not about gaining megapixels. A 36mp image before PS is still a 36mp image after PS. Pentax pixel shift is about automated improved details and colour accuracy of a 36mp image (or 24mp in the case of the K-3 II). But pixel shift the way Sony does it, is somewhat like this. This method is superior to what Sony does but Sony's method is easier than this.
If you look at a gigapixel panorama, you'll find ton more details than in any of thoses pixels shift technology. The final image may be composed of hundred or thousand tiles. A pano like that bring more resolution if viewed at 100%. If you resample to a samller size because you'll not going to print it 120x160" and 300dpi anyway, then you also get increased color deph and reduced noise.

QuoteOriginally posted by Logics Quote
Yeah, right. Like a pentaprism for eye-level viewing or auto focus, or programmed mode or SR or SMC or round aperture blades or oil resistant coating or trailing curtain sync or HSS or TTL or OTF metering or any other non-game-changing feature because it is just a feature like any other feature. Every innovation is a game changer because it introduces to the game a new rule which was not there before.
Nope. Everybody here want a K1 because it is an FF. This is important. But if the K1 had no pixel shift people would still want it exactly the same. If the K1 had no pixel shift, no astrotracer etc but was stiff FF people would still buy it. A bit the same like K1 has slow FPS and no on board flash compared to K3 or even more trivial USB2 instead of USB3, but this doesn't prevent people from still wanting the K1 instead of K3.

Something that is game changing mean everybody want to upgrade and the what you can do drastically change. Pixel shift only improve still subjects but the world not still... That's why this is not a game changer.

QuoteOriginally posted by Logics Quote
None of what you described as being what we had already is what we have now. Pixel shift, the way Pentax does it anyway, is a game changer in so many regards and it does things that no current technique can reproduce. [EDIT] To clarify, the Foveon sensor actually changed the game this way before. This is really not that new but it does it at higher resolution with lower noise, better low-light response and less cost per pixel. To be fair, Foveon were the leaders here.
The difference is foveon does that naturally as a sensor. Pixelshift simulate that by moving the sensor and taking several photographs so that really work only on still subjects. People claim it work on moving subject but they just say really that there not too many artifact anymore. If the photo changed drastically between 2 shots, there no possibility to merge anything and you gained nothing.

As an emulation, this is just that emulation. It bring far less for dynamic range than HDR, it is limited to stacking 4 pictures so it bring far less than old stacking features were you could stack hundred of image if you wanted. For sharpness again the same it bring far less than existing stiching technologies.

Last edited by Nicolas06; 08-02-2016 at 10:57 PM.
08-02-2016, 10:59 PM   #1579
Veteran Member




Join Date: Nov 2013
Posts: 4,854
QuoteOriginally posted by Rondec Quote
Anyway, as I said above, it is one feature that the k-1 offers that isn't widely available from other manufacturers. If you shoot much landscape or macro photography, it could be useful.
I agree this can be useful.

08-05-2016, 10:20 PM - 1 Like   #1580
Senior Member




Join Date: May 2009
Location: Fort Lauderdale, FL
Photos: Gallery
Posts: 212
QuoteOriginally posted by Nicolas06 Quote
Let's no mix up things.
I had a misunderstanding about what you meant here but let us not mix things up. Pentax PixelShift takes you from a 14-bit RAW to a 42-bit RAW. PS was not designed for dynamic range increase, but for detail and colour accuracy increase. With 42-bits of data at each pixel, that is a great deal of dynamic range. For stacking techniques where your camera saves all the exposures in one RAW file, (Pentax does not do that and I do not know any camera that does), sure. Stack as much as you want but the whole, “file too large for my workflow”, argument goes out the window. What you are speaking of is taking several pictures, saving them on a computer as a collection, then using software to create a EXR file or something of the sort. Been done since the dawn of cameras. (Yes, I have done a similar darkroom technique with negative/film; complex, difficult, time-consuming, error prone).

PS allows you to do that in camera in one of two RAW formats. One file out of camera. Simpler workflow! BTW, PS does not keep 14-bit per pixel files; it keeps 14-bits per (R,G,B) per pixel per file and a 32-bit per pixel HDR file keeps 8-bits per (R,G,B,A) per pixel and a 48-bit keeps 12-bits per (R,G,B,A) per pixel, both less than a Pentax PS RAW, even if I told my K-3 to shoot 5 image brackets at 2ev difference.

QuoteOriginally posted by Nicolas06 Quote
Shooting several pictures and averaging them reduce noise and increase color deph.
I misunderstood again, what you meant by colour depth. Clearly, within this context, you are speaking about the colour accuracy and not digital file storage. Yes, you can stack 64 images from a Bayer Sensor and get better colour accuracy (in-camera or PP) from sampling the same colour pixels many times to get a more accurate average than two green and one each red and blue from neighbouring pixels. Each additional image will add to your file(s) size and only marginally increase the colour accuracy. Sony PS does a slightly better job by shifting the pixel about half way in each direction and able to produce a better approximation of actual colour and intensity (and with that, quadruple the image size and file size).

Pentax PS does quadruple the file size but you get completely accurate colour and intensity data at each pixel in one file with no approximation algorithm. Simplified workflow! And all these techniques require still subjects …UNTIL NOW with the Pentax K-1 (within obvious limitations).

QuoteOriginally posted by Nicolas06 Quote
If you look at a gigapixel panorama, you'll find ton more details than in any of thoses pixels shift technology.
True but again it requires a still subject as does both Pentax and Sony PS, and it does so by a multiple factor (depending on how many images you stitch) to both image size and file size. Pentax PS increases the file size by a multiple of four but the image size does not change and it is all done in-camera, no PP, simplified workflow!

QuoteOriginally posted by Nicolas06 Quote
Everybody here want a K1 because it is an FF.
Again, a misunderstanding on my part. I was saying that Pentax's PS is a game changer and on the K-1 with motion sense technology, even more so. I was not saying that the K-! specifically is a game changer. I held out for the Pentax K-3 —still using my film camera for important shoots until the K-3— because it (and the K-5 IIs before it) was a game changer with no AA filter; vastly improving detail. Then the K-3 II came out and the PS was a game changer for me. I still stayed out of the game waiting for a high res FF and here it is. (I waited for the K-3 instead of the K-5 IIs because without an AA, I wanted higer res to help avoid moire).

The K-5 IIs/K-3 were not the game changers; the lack of AA filter was. The K-3 II/K-1 are not the game changers; the PS technology (with motion sense) is.

QuoteOriginally posted by Nicolas06 Quote
The difference is foveon does that naturally as a sensor. Pixelshift simulate that by moving the sensor and taking several photographs so that really work only on still subjects.
Which is what makes the Foveon a game changer. Full colour and intensity information at every pixel of every picture. What made me not choose the Sigma as my first DSLR was ① my investment in Pentax gear and ② not totally satisfied with resolution and IQ. Had they come out with a 16mp Foveon in time, I might be at the SigmaForums message board right now. Foveon is a game changer.

I Think the Sigma SD1 is a better camera than the K-3 but at 15mp images (12-bit per (R,G,B) per pixel) for US$2,000.00, versus the K-3 II 24mp + PS at $850.00 or the K-1 36mp + PS at $1,700; I'll stick with Pentax. To be honest, If I had enough disposable income to run two kits, I would still get it; simplified workflow! (But a full SD1 kit with battery grip and the holy trinity is about US$4k (without an S-TTL flash) and since I already have glass & two P-TTL flashes, a K-1 investment is only about $2.3k with battery grip, etc.).
08-06-2016, 02:26 AM   #1581
Veteran Member




Join Date: Nov 2013
Posts: 4,854
QuoteOriginally posted by Logics Quote
I had a misunderstanding about what you meant here but let us not mix things up. Pentax PixelShift takes you from a 14-bit RAW to a 42-bit RAW. PS was not designed for dynamic range increase, but for detail and colour accuracy increase. With 42-bits of data at each pixel, that is a great deal of dynamic range.
No this isn't 42EV of luminance information (what dynamic range is basically about) whatever the light frequency used (red, green or blue). This is at best 4X more dynamic range. So a best 4X would be 2EV if we were using photosites without color filters. Here it is less because colors frequencies are filtered. If we suppose that at photosite level the dynamic rnage is matching the number of bits of the file format, they we get a theoretical max of 16EV of dynamic range. Not 42.

If you take different exposures, you get much more information of that dynamic range because you record different part of the signal. But taking 5 pictures separated by 2EV each, you actually get 8EV of dynamic range. Pixel shift use the same strategy but for light frequency, not dynamic range. You can't have it all. Would you want both, then you'd get 4x5 = 20 image with pixel shift and different exposures.

Last edited by Nicolas06; 08-06-2016 at 11:34 PM.
08-08-2016, 02:28 AM - 1 Like   #1582
Senior Member




Join Date: May 2009
Location: Fort Lauderdale, FL
Photos: Gallery
Posts: 212
QuoteOriginally posted by Nicolas06 Quote
No this isn't 42EV of luminance information
QuoteOriginally posted by Nicolas06 Quote
You can't store this information in a single raw/jpeg but a standard exist for 32 bit per pixel HDR files instead of 8bit jpeg or 12,14 or 16 bit raws.
I never said that nor suggested that PS stored 42EV of luminance. I specifically said that it was 42-bits per pixel or 14-bit per (R,G,B) per pixel. I also stated that a 32-bit per pixel file is still 8-bits per (R,G,B,A) per pixel and a 48-bit per pixel file is 12-bits per (R,G,B,A) per pixel. Exposure stacking by taking several exposures, e.g., one at -2EV, one at 0EV and one at +2EV then stacking them, still gives you only one colour per pixel, the actual luminance (and eventual colour) is still approximated at each pixel, and you still end up with three files out of camera. Stacking five gives you five files out of camera so the workflow has 3-5 times more data which still has approximated luminance and colour. PS gives one file out of camera with accurate colour and luminance data at 4x file size but simplified workflow.

As for OpenEXR, the HDR file format developed and used by ILM (and most others) boasts,
QuoteOriginally posted by OpenEXR:
“OpenEXR's features include: Higher dynamic range and color precision than existing 8- and 10-bit image file formats….”
Note that it did not mention 12-bit image file formats (which it arguably equals) nor 14-bit image formats (which beat it). That being said, it continues to say that it also supports a 16-bit float, a 32-bit integer, and a 32-bit float. But normal format is a 16-bit float because,
QuoteOriginally posted by OpenEXR:
32-bit floating-point TIFF is often overkill for visual effects work. 32-bit FP TIFF provides more than sufficient precision and dynamic range for VFX images, but it comes at the cost of storage, both on disk and in memory.
This is how it is described:
QuoteOriginally posted by OpenEXR:
ILM decided to develop a new HDR file format with 16-bit floating-point color component values. Since the IEEE-754 floating-point specification does not define a 16-bit format, ILM created the "half" format. Half values have 1 sign bit, 5 exponent bits, and 10 mantissa bits. For linear images, this format provides 1024 (2^10) values per color component per f-stop, and 30 f-stops (2^5 - 2), with an additional 10 f-stops with reduced precision at the low end (denormals).
In other words, it sacrifices colour data precision for increased luminance detail in the shadows. That is fine, considering the range for a reflected projected image and the way the human eye works. We see more luminance detail in low light but far less colour accuracy while we see great colour in bright light but less luminance detail. ILM and other movie studios really need the luminance detail for PP work and small file sizes are important when you have hours of footage at 24 individual images per second. Pentax's 42-bit integer PS files are larger with less luminance but more accurate colour in shadows (and are not shot at more than 4.3 individual images per second). This is great for when you want to pull out shadow details but keep its colour accuracy.

So using EXR at 32-bit integer, we get (signed) 10-bit per (R,G,B)+T per pixel (the pixel is either visible or invisible) or (unsigned) 8-bit per (R,G,B,A) per pixel (the pixel has 256 levels of transparency from invisible to opaque). Still not better than 42-bit unsigned (R,G,B) or 48-bit unsigned (R,G,B,A). Otherwise, we increase luminance drastically (dynamic Range) by sacrificing shadow colour significantly for 16-bit float. Or, we can choose to not sacrifice colour by going to 32-bit floating point. not to mention, more processing power needed for floating point colour components.

tl;dr →
Bracketing and storing in a HDR format over using one large 42-bit PS PEF/DNG either creates
① large sets of files (original bracketed shots plus post-processed composited HDR int file) with less dynamic range, complicating your workflow or
② a large set of files (original bracketed shots) plus one final image (post-processed composited HDR fp file) with colour detail lacking in the shadows but immense luminance detail (dynamic range), requiring intense processing power, complicating your workflow.


Last edited by Logics; 08-08-2016 at 02:36 AM.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
auto, base, camera, company, compression, d810, design, dr, electrons, fa, hardware, iso, k-1, k-3, lenses, pentax, pentax body, pentax k-1, pentax news, pentax rumors, photos, pre-order, risk, sensor, specifications, timelapse, trip, vs
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Pentax K-3 II Officially Announced Adam Pentax News and Rumors 1014 07-03-2015 10:55 PM
Pentax K-S2 Officially Announced Adam Pentax K-S1 & K-S2 12 05-23-2015 06:49 AM
Pentax K-30 Officially Announced! Adam Pentax News and Rumors 245 09-12-2012 08:32 PM
Pentax K-5 Officially Announced Adam Pentax News and Rumors 533 03-06-2012 05:45 AM
K-5 Firmware 1.02 Officially Announced Ole Pentax K-5 & K-5 II 50 01-20-2011 10:05 PM



All times are GMT -7. The time now is 04:02 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top