[RobA_Oz]

The D750 was announced in september 2014. The K-3 II was announced in april 2015. The KP is really new. Most of what you're seeing here is sensor technology development (even though admittedly Nikon is cheating more than Pentax is).

Was the K-3II sensor significantly different from that of the K-3? The K-3 was announced in October 2013, so, if the sensor wasn't developed further to reduce noise, the performance gap is even easier to explain.

[arnold]

Top left Nixon
Top right KP
Bottom left k70
Bottom right k3ii

I go with this too.[COLOR="Silver"]

---------- Post added 15-04-17 at 08:43 ----------

[pentageek]

Top left, Pentax K3 II
Top right, Pentax KP
Bottom right, Pentax K70
Bottom left, Nikon.

[tromboads]

...I love how there's one such comment in every gear thread. Completely off-topic, and doesn't even add anything to the thread.

Yes Guilty. I just can't help but add a dose of reality every now and then. That's what is on topic.

[RobA_Oz]

Yes Guilty. I just can't help but add a dose of reality every now and then. That's what is on topic.

"Granularity", perhaps. The ultimate purpose of photography is to make pictures. The technicalities of the photographic process are also "reality".

---------- Post added 15th Apr 2017 at 02:58 PM ----------

I go with this too.[COLOR="Silver"]

---------- Post added 15-04-17 at 08:43 ----------

Top left, Pentax K3 II
Top right, Pentax KP
Bottom right, Pentax K70
Bottom left, Nikon.

You must have overlooked post #19.

[starbase218]

Was the K-3II sensor significantly different from that of the K-3? The K-3 was announced in October 2013, so, if the sensor wasn't developed further to reduce noise, the performance gap is even easier to explain.

Well, look at at this way: if it wasn't, then the most likely reason for Pentax to use a similar sensor (or maybe even the exact same one) would be that there was no other sensor at the time that was significantly better. So it could still be seen as an indicator of sensor performance at that time.

[pentageek]

You must have overlooked post #19.

You are absolutely right! Thank you, otherwise I'd be waiting in vain to see solution of this riddle

[normhead]

I'm ....that's a two stage process, decide which is better or worse, then decide which camera "should" take the best or worst images.

The D750 "should" be the best image -top right.
The K-P "should" be the next best image - bottom left.

At that point, I have no idea which should be the next best image K-3ii of K-70, so I have no way to rate the final two. But the bottom right is the next best image and top left is the worst image.

The two stage prices of using image test sites to find out which should be best, to be able to attach a name to these two images is more than I am willing to take on.

I would have preferred to just rate the images, then find out what camera took them, without turning it into a a test of people's rating biases.

But hey, that's just me, thanks for doing this. This is so much more interesting than just talking about what everyone thinks is better. That's always all about the biases.

[leekil]

Well, look at at this way: if it wasn't, then the most likely reason for Pentax to use a similar sensor (or maybe even the exact same one) would be that there was no other sensor at the time that was significantly better. So it could still be seen as an indicator of sensor performance at that time.

I would think that the reason to use the same sensor is that it is much more work to develop and debug a camera using a new sensor, than to do a minor update to the K-3 that avoids that effort.

[starbase218]

I would think that the reason to use the same sensor is that it is much more work to develop and debug a camera using a new sensor, than to do a minor update to the K-3 that avoids that effort.

That too. But you have to keep in mind that, whatever sensor they went with at the time, they also had to look ahead. The K-3 II has been in production for about 2 years already. If there was a better sensor available at the time, maybe it would have been in their best interest to put a little more resources into making that sensor work than to continue on with the existing sensor.

[Nicolas06]

Grabbed a couple of ISO25600 testshots off Dpreview detailed camera reviews (all raw files) and converted them all with no noise reduction, no curves, no sharpening, basically only with the built-in profile Darktable applies and all other modules turned off.

I wanted to look at noise patterns, color noise versus luminosity noise and detail retention but I did not want to look at the clean files after a lot of PP like most of the reviews and comparisons do, thinking that any NR I can apply would likely obliterate any objective differences between the sensor outputs.

I then combined a crop of the same area (ca. 2000x1300 pixels) of the testshot of all 4 cameras without scaling any of them but flipping some images horizontally, vertically or both in order to be able to properly judge identical areas in close proximity without allowing my eye to get distracted by wandering across too much.

The result is below and I find it quite surprising actually. Cameras are the Nikon D750, K-3 II, K-70 and K-P but I'll leave you to decide which quadrant is which camera. (click through to Flickr for full size)

First problem with that assumption is that it has been years since even raw are "cooked" with some post processing so basically this just mean the raws with the most post processing done in camera win.

Second problem is what count is what people typically get. So that either OOC JPEGs, or RAW post processed automatically with noise reduction from lightrom/camera raw or DxO. And this is interesting the raw processing doesn't apply the same setting to all camera because the goal for them is to get the best possible result, not the one where the camera look as worse a possible as to grow the difference.

The idea is more with our raw processing software all camera look good. And they manage it, mostly. There still difference, but not as much as one might think.

[clickclick]

I'm ....that's a two stage process, decide which is better or worse, then decide which camera "should" take the best or worst images.

The D750 "should" be the best image -top right.
The K-P "should" be the next best image - bottom left.

At that point, I have no idea which should be the next best image K-3ii of K-70, so I have no way to rate the final two. But the bottom right is the next best image and top left is the worst image.

The two stage prices of using image test sites to find out which should be best, to be able to attach a name to these two images is more than I am willing to take on.

I would have preferred to just rate the images, then find out what camera took them, without turning it into a a test of people's rating biases.

But hey, that's just me, thanks for doing this. This is so much more interesting than just talking about what everyone thinks is better. That's always all about the biases.

I have to admit I took the bait from the OP saying they were surprised by the results. That lead me to thinking what would be the biggest surprise? The full frame camera being bested by 3 APS-C cameras. Then it became a question of ranking, and in my mind for low light performance, I was looking for K3II->K70->KP. Putting aside that I had the wrong cameras attributed to the samples, what really surprised me was how subjective I found trying to decide between the bottom two. The KP was obvious to me, but depending on which tile I was looking at, I found much more subjectivity as to which one had the better overall performance across the most colors.

It also makes me wonder what our next APS-C flagship will be like for low light ISO plus other features. If it does nothing but build on all the pluses of these 3 Pentax cameras, we'll have quite a nice new addition to the lineup.

[Rondec]

First problem with that assumption is that it has been years since even raw are "cooked" with some post processing so basically this just mean the raws with the most post processing done in camera win.

Second problem is what count is what people typically get. So that either OOC JPEGs, or RAW post processed automatically with noise reduction from lightrom/camera raw or DxO. And this is interesting the raw processing doesn't apply the same setting to all camera because the goal for them is to get the best possible result, not the one where the camera look as worse a possible as to grow the difference.

The idea is more with our raw processing software all camera look good. And they manage it, mostly. There still difference, but not as much as one might think.

I don't think there is much "pre-cooking" going on in the RAW files with the K-P. kh0123456789 looked at files with Raw Digger and found no evidence of that, whereas raw files from the K5 and K3 do evidence some noise suppression above iso 1600 (for K5) and iso 3200 (for K3). Pentax KP vs. D750 raws at high ISO 25600 - Pentax APSC on par with Nikon FF - PentaxForums.com

If you truly have an APS-C RAW file that has not been smoothed at all that has similar noise characteristics to a full frame RAW at this sort of iso, that is just flat out impressive. Sure, you can de-noise any or all of the images, but the ones that have the most noise at baseline are going to look worse after the process, whether that means looking overly smoothed and plastic or still more noisy.

I will say that dynamic range will probably be significantly less with APS-C files than with full frame, even if noise characteristics are the same and that is probably the main issue I see with high iso images from any camera.

[Simen1]

I will say that dynamic range will probably be significantly less with APS-C files than with full frame, even if noise characteristics are the same and that is probably the main issue I see with high iso images from any camera.

DR and noise are closely coupled. When increasing the signal for higher then base ISO or well depth for base ISO then DR increases as well.

ISO are just an amplifier that may clip the signal. ISO change should not change the noise in theory but in practice noise may be slightly affected. So in theory DR will be reduced linear to the amplification ratio. Think of the ISO as an amplification ratio expressed in percent. For example ISO 200 are a 2x amplification ratio. Both signal and noise are amplified equally, but the signal may be clipped if high enough.

[Simen1]

I wonder how the K-1 crop mode would compare? Just to get a sense of sensor per area quality. K-3II-like or K-P like.