[BigMackCam]

Actually, I think the test shots are fine... yellow, under-exposed, but fine - if we had exactly the same test shots, taken at the same time in the same lighting, with the K-1. That's what we're missing so far... side-by-side, like-for-like comparisons. This is a challenging subject in terms of lighting and detail...

[Not a Number]

How do the results look with no PP done (sharpening, NR, etc.)

I'd like to see similar tests done with KP and/or K-70.

[BigMackCam]

How do the results look with no PP done (sharpening, NR, etc.)

I'd like to see similar tests done with KP and/or K-70.

That's a reasonable question.

If you're asking about the posted links to the K-1II raw files, you can check that for yourself. I have - in Lightroom 6, RawTherapee 5.4 and Darktable 2.4.1. The processing looks slightly different in each piece of software. There is definitely some loss of detail visible in all of them, but whether it is different to, or more / less than, the equivalent shots with a K-1, we just don't know - and won't, until we see identical side-by-side comparisons...

[Class A]

...underexposure is not a waste either...

You have to be careful about underexposure when looking at noise in images.

An underexposed image shot at ISO 800 that requires two stops of pushing in post, is equivalent in noise to a correctly exposed ISO 3200 image. The same applies to any kind of smearing, of course.

[Igor123]

You have to be careful about underexposure when looking at noise in images.

An underexposed image shot at ISO 800 that requires two stops of pushing in post, is equivalent in noise to a correctly exposed ISO 3200 image. The same applies to any kind of smearing, of course.

I thought that was the intent in that test? - to underexpose the iso 100 shot and then push it to the same exposure and also get the same amount of light and noise, and then using different isos to see if the camera preprocesses the iso 100 and 800 shots differently (which it seems to do a bit?)

[aikaarska]

I thought that was the intent in that test? - to underexpose the iso 100 shot and then push it to the same exposure and also get the same amount of light and noise, and then using different isos to see if the camera preprocesses the iso 100 and 800 shots differently (which it seems to do a bit?)

Indeed. That's purpose of the test. And pushed ISO100 exposure shows some details more in shadows than ISO800 sample. It should not be that way. But it is - because of the new NR algorithm which eats details when ISO800 or higher ISO used (also affects to RAW )...

[stevebrot]

How do the results look with no PP done (sharpening, NR, etc.)

That is on my task list for the day. Dcraw allows for bare bones RAW processing and should work with K-1II DNGs.


Steve

[stevebrot]

But it is - because of the new NR algorithm which eats details when ISO800 or higher ISO used (also affects to RAW )...

...so far, not demonstrated by any examples.


Steve

[stevebrot]

...underexposure is not a waste either, if you are testing the camera's performance - and know what you are doing ;-)

What one gets with intentional underexposure is less data per pixel and what is being tested is the image processor's and PP tool's skill in creating tonal gradation where there is none. In other words...fake data. When one ups exposure in LR or ACR, all that is being done is tone mapping with clean-up.


Steve

[SSGGeezer]

I personally don't see a huge difference in the furry images at forum quality but I am learning a lot about induced noise though post processing of underexposed images and such. I learn something new here every day!

[stevebrot]

An underexposed image shot at ISO 800 that requires two stops of pushing in post, is equivalent in noise to a correctly exposed ISO 3200 image.

Sorry, but I am not following you here. Are you saying that noise depends, at least partially, on the amount of light striking the sensor and that underexposure (less light) creates noise?


Steve

[photoptimist]

Sorry, but I am not following you here. Are you saying that noise depends, at least partially, on the amount of light striking the sensor and that underexposure (less light) creates noise?


Steve

Yes, but it's a different kind of noise that what people often think about.

First, there's various types of noise intrinsic to the sensor's silicon and electronics that are added to the signal and multiplied by electronic or digital ISO gain. Even with the lens cap on, the image has noise.

Second, there's also the Poisson noise in the signal itself because the arrival of photons is not perfectly smooth. Instead, there's a random chance that more or fewer photons arrrived from some bit of the scene. Even if the sensor and electronics were perfectly noise-free, the image would still show "noise." That Poisson noise source is proportional to the square root of the light level.

For example, a pixel that should be getting a signal of exactly 1000 electrons will actually show a standard deviation of 30 electrons from shot to shot. Or, if a patch of pixels all see a uniform surface with 1000 e/pixel, there will be speckling from pixel to pixel of 30 electrons. That's a ±3% variation with some chances of ±6% or more. If you underexpose that scene by 2 stops so that each pixel should be accumulating only 250 electrons, then the Poisson noise will be about 16 electrons or about ±6% with some chances of ±12% or more.

(P.S. This physical phenomenon is one cause color noise in high-ISO shots. A gray card image that should have equal numbers of electrons in the R, G, and B pixels will show Poisson noise across the channels -- maybe the R and B pixels in one sport caught 3% more electrons but the G pixel caught 6% fewer to create a magenta blotch in the grey.)

[stevebrot]

Second, there's also the Poisson noise in the signal itself because the arrival of photons is not perfectly smooth. Instead, there's a random chance that more or fewer photons arrrived from some bit of the scene. Even if the sensor and electronics were perfectly noise-free, the image would still show "noise." That Poisson noise source is proportional to the square root of the light level.

OK, I understand the concept. The effect would be subtle at best except in low light where outliers on the high side are disproportionately represented*, but exacerbated by amplification (gain). The problem is compounded by A/D conversion into low bit-depth representation.

In other words...makes sense. I will stuff this into my hat.

Is it save to assume there is algorithmic relief?


Steve

* FWIW, standard deviation is sort of a sketchy statistic for events on at the low limits of detection.

[Ex Finn.]

This must be the most "fan-boy" attended thread I have ever seen on Pentax-forums!
edit: or at least it ranks very high on the list...

[BigMackCam]

This must be the most "fan-boy" attended thread I have ever seen on Pentax-forums!
edit: or at least it ranks very high on the list...

I don't see that, in all honesty. I can understand folks being skeptical - defensive, even - until we see side-by-side comparisons between the K-1 and K-1II. The early reputation of the camera - both on and off these forums - is at stake, after all