[Rico]

Are you sure about the 5 seconds? This does not seem to be my experience with the K-1 (although I never measured the time it needed). I just did a quick test with the K-3 III with an exposure time of 1/125 and it was able to fire again after 8.5 seconds using a V90 card.

The resolution thing is not so simple. The amount of pixels is obviously the same, but the ability to reproduce small details accurately is quite a bit higher with Pixelshift.

Simplifying some of the problems involved, sampling theory says that for the green channel the resolution of a Bayer sensor is the same as that of a monochrome sensor; for the red and blue channels it is half of that. For the usable resolution the demosaicing technology is critical. This article concludes that “adaptive interpolation can lead to X and Y axis resolution as high as a monochrome array with the same pixel pitch” (p. 245). Practically, however, much of the information near the resolution limit risks being destroyed by aliasing and demosaicing artifacts. Part of the beauty of Pixelshift is that false colours resulting from these ugly things completely go away.


I would like to add that this holds for the Pentax implementation but less so for Sony’s. Judging from the A7R IV Pixelshift sample in DPR’s studio shot comparison tool, its output is not free of colour artifacts (but four times the pixel size).

I am certain it takes the K-1 about 5 seconds before the camera is ready to take another image using Pixel-Shift so it is not good news to hear it takes the K3III 8.5 seconds. Sad news really.

[sbc]

I think it depends on the scene but just tested it and it took 6.5sec.
Resolution does not increase but shooting at ISO6400, I can clearly see that noise has reduced significantly.

[phoebus]

My K-1 does not do hand-held PS, the PS save seems to be just be the time taken to [do motion correction and] write the raws/jpg. With the K-1ii hand-held PS was added, the camera has to align the different frames precisely - presumably using camera motion during the shot as part of the calculation - to produce the jpg. The K-3iii doesn't have hand-held PS either, but am I right to believe it produces a composite RAW and possibly does a better job of motion correction? Are we comparing apples, bananas and pears here???

For me, pixel shift only truly makes sense with completely static scenes - so the processing time isn't really an issue - it's not like I'm missing something while the camera does it's thing.

[wkraus]

I am certain it takes the K-1 about 5 seconds before the camera is ready to take another image using Pixel-Shift so it is not good news to hear it takes the K3III 8.5 seconds. Sad news really.

Try again. I just did the same test as before with the K-1 and it took it 13 to 14 seconds to be ready for the next shot. It takes a little more than 5 seconds until the “Processing…” screen goes away, but that does not mean the camera can fire again. So the K-3 III is ready a little faster than the K-1.

[Robert N]

As a follow-up to my last post, here is a test shot (an old Paterson test target) developed with and without Pixelshift to demonstrate its effects. The lens used is the SMC D FA 50mm F2.8 Macro at f/6.3. I used three different raw converters, Adobe Camera Raw 12.2 (no Pixelshift functionality as yet), RawTherapee 5.8, and Digital Camera Utility 5.9. Incidentally, this also demonstrates how differently the demosaicing works at pixel level – but the test pattern is a real stress test, under normal conditions the differences are less obvious.

These are full-size crops. I edited the images for identical luminosity and contrast and neutral grey, but did not attempt to get similar colours. Due to the complexity involved, I also did not try to apply the same sharpening. In DCU sharpening is set to zero but nevertheless the software seems to apply some rather crude sharpening.

Adone Camera Raw:


RawTherapee:




Digital Camera Utility:




Feel free to download the images if you want to take a closer look.

Now that I have owned a K-3iii for 3 months, I thought I had better try out the pixel shift comparison myself, using the excellent HD DA 16-85mm F3.5-5.6 ED DC WR Lens.
I am sure if I posted the before and after images, the web resolution would be insufficient to show a resolution difference. However, processing both RAW images in exactly the same way and zooming in tightly on the computer monitor, the increase in resolution is evident in the fine detail, which is impressive.

[bobbotron]

Thought this thread could use some more images. I can't really tell that much difference with PS with the K3iii, but the images do come out crisp. I wish I had set my lens to f/8 or f/11, it gets a bit soft in the corners because of DOF.

[jersey]

I use it to photograph highly iluminated architecture (airport terminal, train stations) and it does work, allowing for better ability to bring out details from shadows (when exposing for highlights), but has a drawback of bringing out the atmospheric haze. So it does work pretty well. But if someone want more resolution (what for?) or bigger image (same question here) then nope.


Proccessing time - I never really measured it, but the more details the longer it takes. If I photograph a station where most details are big and flat it is pretty fast, but when shooting something more intricate like decorative facade, especially with more industrial look with lots of drilled holes and pipes it takes forever.

[titrisol]

New owner here, tested PS with macro and it makes a world of difference. Macros are sharp and detailed.
However RAW files are in the 100MB order!

[phoebus]

New owner here, tested PS with macro and it makes a world of difference. Macros are sharp and detailed.
However RAW files are in the 100MB order!

That's because there are 4 26MPix RAW images in each K-3iii PS RAW, so file is roughly 4 x bigger than standard (depending on subject - they have lossless compression).

[Hayashi]

For new owners of the K3-iii, it would be interesting to know how the pixel shift performs. Points of interest are for when shooting in RAW:

As a rough percentage, how much is the resolution increased (I believe the file size is the same as for a single shot).
How does the resolution compare to a single frame of the K1 (for owners of both the K-3iii & K1).
Is the pixel shift effective at compensating for moving objects (typically trees blowing in the wind).

Looking forward to your replies.

Actually you can test it.

Take one photo in raw with Pixel Shift

Use the PDCU to open the raw, it allows you to switch on and off of the pixel shift function.

You can see the difference.

Generally I'd say the pixel shift got about 10-20% more detail than non pixel shift one.

[ThorSanchez]

Here's a K-3 III non-pixel shift vs. pixel shift comparison. Camera sitting on my desk, 2 second timer. DA 20-40 Limited at about 24mm. Processed to taste in RawTherapee, including a good bit of sharpening added in high-contrast areas. ISO 1600... just because? 200% crop, so much tighter than you'd typically view.

There's a little bit of extra detail, a little better noise performance. This is in line with my previous experiences with pixel shift on the K-3 II and III, that there are only a few specific edge cases where pixel shift makes a noticeable difference in typical viewing conditions.

[ThorSanchez]

Here's a couple more at 200%. This time at ISO 100. If you can tell the difference you have a more discerning eye than I do. I think it's clear that there's an impact on high ISO noise, but if you're already on a tripod why aren't you shooting near base ISO?

[Gimbal]

Here's a couple more at 200%. This time at ISO 100. If you can tell the difference you have a more discerning eye than I do. I think it's clear that there's an impact on high ISO noise, but if you're already on a tripod why aren't you shooting near base ISO?

The difference should be in the details, but they are all wiped out by high jpeg compression.

[wkraus]

Here is an edge case, posted before:
Pixel shift performance of the K-3iii - PentaxForums.com

[ThorSanchez]

The difference should be in the details, but they are all wiped out by high jpeg compression.

What's high compression? I have RawTherapee exports set up for 95% jpeg quality and whatever "best quality subsampling" means.