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Forum: Pentax K-1 5 Days Ago  
K-1mkII overpowered NR. Firmware update?
Posted By lennyl
Replies: 87
Views: 3,952
I do not believe in all the reviews. I sold K-1 and bought K-1 II.


benefits for K-1 II:
- accurate AF-S (no hunting), better AF-C (only about 5% of inaccurate focused photos)......but only for spot AF point and A-9/SEL-2 mode
- Pixel Shift Resolution to be used handheld without artefacts
- K-1 II ISO 16.000 look like ISO 12.800 on K-1


on the left K-1 II, on the right K-1....the same lens, the same settings (DNG, NR OFF.....export from Adobe Lightroom CC2015 without adjustments)
AF-C SEL-2, ISO 1.250, Tamron AF SP 70-200mm f/2,8 Di LD (IF) Macro

AF-S spot AF, ISO 6.400, Pentax HD PENTAX-D FA 150-450mm f/4.5-5.6 ED DC AW



I would buy K-1 II again if someone asked me.
Forum: Pentax K-1 6 Days Ago  
K-1II review... Opportunity to get banned on DPR
Posted By Racer X 69
Replies: 428
Views: 19,199
Looks like this discussion has run the course.


Time for everyone to go out and try and squeeze the most from their "inferior" Pentax gear.


Forum: Pentax K-1 05-16-2018, 07:07 AM  
K-1mkII overpowered NR. Firmware update?
Posted By Rondec
Replies: 87
Views: 3,952
I don't care if Pentax makes the iso that the accelerator kicks in optional or not. I think these threads are full of pixel peepers perseverating over very tiny differences that just aren't going to make any difference for 98 percent of images shot at normal viewing/printing sizes. Beyond which, if you are wanting to print maximal sizes, you are going to want to shoot as low iso as possible -- not in the iso 800 plus where the accelerator chip will be kicking in.

Long story short, DP Review has made Much Ado about very little and while you can pick out miniscule differences between the K-1 and k-1 II, the end results are going to be more similar than different.
Forum: Pentax K-1 05-17-2018, 03:12 AM  
K-1II review... Opportunity to get banned on DPR
Posted By Rondec
Replies: 428
Views: 19,199
You are right, if you have a good copy of the 50 macro. But apparently theirs has decentering or something as the right upper quadrant of their test image is really soft throughout. As it currently stands, people are constantly pulling bits out of that part of the image and you can't draw much conclusion from them as a result.

As to the general question, I have yet to see someone take a photo which was "damaged" by the noise reduction offered by the K-1 II. Obviously this is a new camera and so we don't have much in the way of examples, but I see people blowing up pixels and pointing out specks of dust that may be missing at iso 800. But when I shoot at iso 800 it isn't generally with the intention of printing big enough that dust pixels will show up and the bigger issue is whether the overall image is effected and my guess is that it isn't.

I still am waiting on the astro photographers among us to test if this will affect star fields (I don't shoot astro myself), but that is the one application where I think this might have a negative aspect to it.

In general, I have said before and I will say again, the accelerator more than matches the majority of photographers ability to denoise an image without losing detail, with minimal time and effort involved. And that second part is really important as well and not to be glossed over. Even if you can get roughly the same results running your images through DXO Mark's PRIME noise reduction software, that takes time -- quite a bit of time to run each image through. From an efficiency stand point, this is a definite winner with minimal clear loss.

It feels as though you and several others are arguing more on the principle of the thing. RAW files just should be pure with minimal pre-processing done on them. Even if you could show that no detail was lost at all it would just feel wrong to do noise reduction of some kind on the RAW file.

I wouldn't be surprised if Pentax does eventually allow some tweakability to this to allow it to kick in at different isos, but certainly at the upper end of the iso spectrum there is no point to even shooting those unless you have some noise reduction, whether in camera or out of camera.
Forum: Pentax K-1 05-11-2018, 08:42 PM  
K-1 MK2 - Unhappy with results at moderate ISO settings
Posted By Ian Stuart Forsyth
Replies: 547
Views: 22,989
I think it is more important to expose for where you want white to fall within the sensor ability to convert light information into data. If you expose for the shadows you are unknowing placing where you record white within the saturation space you are allowed and clip tonal values in zones 10-8.



You can easily test this by reduce the read noise that is captured in a image, this can be done by selection an exposure at base iso ( where we see the highest level of read noise) and then raising the iso to the point just before the camera uses NR and or stops using gain)
I am using the D800 as that is the only camera that is charged now

You can see that at iso 100 it produces 3.4 electrons and at iso 1600 it produces 2.3 electrons

To test this lets take 2 images that use the same exposure f/2.8 1/6 while changing the iso levels, one at iso 100 and the other at iso 1600 and look at objects that fall in zone 1-3



The top one is iso 100 and the bottom is iso 1600, for the iso 1600 I had to adjust the output brightness to the same level as the iso 100 shot, and because I increase the iso to 1600 I clipped all the data found above middle grey but as you can see that when I decease the read noise there is little effect on the noise we see between the 2 image.

However if I was to lift the shadows to the point that these tone values enter into the middle and highlights as you would in a HDR image then yes we would see some noise variances. Sony sensors produce so little read noise that they are really noiseless until we dig deep into the shadow well below the 10 zones that we can display as a medium, its the shot noise that decides how much noise we see in most of our work until we start doing HDR and compressing the full DR the sensor can capture into that of what we can display our images, shot noise is still greater contributor in a lot of what we shoot.
Forum: Pentax K-1 05-10-2018, 10:16 PM  
K-1II review... Opportunity to get banned on DPR
Posted By Shivaess
Replies: 428
Views: 19,199
What is wrong with you? This is an inflammatory post when I have been nothing but polite. The person I quoted is a well respected technical expert who owns a business analyzing sensor data. He has also been nothing but professional on "the site that shall not be named". I have used the technique outlined because while its not fool proof I'm not about to buy a K-1 to test my K-1ii against to determine if I should swap them out.

Iso invariance - PentaxForums.com
There now I'm quoting this site. Please have some manners in the future.
Forum: Pentax K-1 05-10-2018, 06:52 PM  
K-1II review... Opportunity to get banned on DPR
Posted By photoptimist
Replies: 428
Views: 19,199
For linear filters (e.g., averaging adjacent pixels together or various convolution-based noise filters), the relationship between noise reduction and detail reduction is a mathematical fact. And if Ricoh is only using simple NR, then people have reason to be concerned about the accelerator.

Nonlinear filters are a differ beast entirely. There's a lot of really clever signal reconstruction methods that use what is known about the statistical properties of noise versus the statistical properties of signals to maximize noise removal while minimizing signal degradation. Maximum likelihood estimators, for example, can look at a set of pixels and slightly correct them to make them less noise-like and more signal-like. And we must admit that the splotchy saturated speckles of chroma noise, for example, are extremely unlike any image. Moreover, even if you take a picture of chroma noise splotches, a properly designed filter would notice that the image is "too splotchy" for just noise and not entirely remove the splotches that are actually in the scene.

It's going to take a lot more that an FFT of the noise to characterize what the chip is doing and whether it affects images in any detrimental way.
Forum: Pentax K-1 05-11-2018, 09:11 AM  
K-1 MK2 - Unhappy with results at moderate ISO settings
Posted By stevebrot
Replies: 547
Views: 22,989
Now you are in Voodoo territory...cue the theramin...


Steve
Forum: Pentax K-1 05-09-2018, 08:52 PM  
K-1 MK2 - Unhappy with results at moderate ISO settings
Posted By Ian Stuart Forsyth
Replies: 547
Views: 22,989
It really depends on why and how it becomes significant, even when we are shooting at base iso it really is not that hard to find the tell tail signs of shot noise in a photo.

The biggest hurdle is that for the first 3 stops of the tonal range(zone10-8) in a scene is using 75% of the space a sensor can store as light information( signal).

take this photo



If you take a look at 100% you can see shot noise creeping in easily, on the right the image is take using the cameras meter set on middle grey and the right one stop larger exposure

https://photos.smugmug.com/Temp/Temp/i-cZF7J45/0/c819217b/O/_1710418%20crop.jpg

The reason why is how light information is captured, if we expose to the right and place objects found in a scene to appear as white close to clipping ( zone 10) as not to clip that signal is near saturation and we have captured a lot of information.
Now here lies the problem anything that falls in zone 9 only captures half the signal as zone 10. Here this still is not a big deal as our signal is still rather large and shot noise has very little influence.

Now we go to zone 8 it has only gather a signal that is 1/4 of the signal that zone 10

zone 7 gathers only 1/8 the signal

zone 6 gathers only 1/16 the signal that was captured in zone 10
Now we hit zone 5 middle grey has only captured 1/32 or 3% of the signal that was captured at zone 10 , now we start to see the tell tail signs of shot noise. 94% of the capacity of what the sensor can store is used up in the first 4 stops in tonal range of a scene. Naturally this is where we like to place most of the detail of our image is in zone 5 that only uses less than 3% of the saturation capacity of the sensor.

Dip down to zone 4 where we will place a lot of our darker tones and that is only made up of 1/64 of the light that the sensor can store( less than 1.5%) now shot noise is very easy to find.
Forum: Pentax K-1 05-09-2018, 12:19 PM  
K-1 MK2 - Unhappy with results at moderate ISO settings
Posted By stevebrot
Replies: 547
Views: 22,989
They also could have negotiated K-cup support with Keurig. Just saying...


Steve
Forum: Pentax K-1 05-09-2018, 10:28 AM  
K-1 MK2 - Unhappy with results at moderate ISO settings
Posted By Rondec
Replies: 547
Views: 22,989
I took a look through that scene and honestly, there is not enough difference between those. Maybe a hair more detail in the A7r III image, but it is realy hard to say because noise often gives the impression of detail that isn't really there. Clearly there is less noise in the K-1 II image. Also the A7r III seems to have odd color shift where black lines almost have a brownish look to them. Not sure if there is just a bit more moire with the A7r III image or what is going on there.

Regardless, if that's the goal we are all shooting for then the K-1 II is already there. :)
Forum: Pentax K-1 05-08-2018, 01:00 AM  
K-1II review... Opportunity to get banned on DPR
Posted By pid
Replies: 428
Views: 19,199
First I think, the K1II is not expensiver than the K1 was before. The K1II is as good as the K1. The K1II has some kind of improvments. The K1 is still a very good cam with a similar IQ to the K1II. The K1 is now cheaper as the K1II.
Second thought: you can buy both cameras and will be happy. The Upgrade is a little bit to expensive, but a friendly idea from Ricoh for those who will get the newest standard from Ricoh.
Third thought: you buy a camara as it is. No firmwareupdate makes a new camera out of it. Sometimes some little improvements can be made or little features can be added. Most times the camera does not feel like an other camera afterwards.
So if you have a K1 be happy. If you dont have a k1 buy one for a really good price for an FF cam. If you want the little improvements buy the K1II and be also happy. Both are woth every penny and can make a lot of fun and produce very good pictures.
So what is the problem?
Forum: Pentax K-1 05-07-2018, 06:22 PM  
K-1II review... Opportunity to get banned on DPR
Posted By rawr
Replies: 428
Views: 19,199
Probably not. Unless it impacts some other qualities of the image - eg interferes with various colour channels.

I think the level of micro-analysis performed here by tech gurus like Bill Claff and Iliah is important and useful, but in the real-world, the results of any mandatory NR will not be something ordinary folks will ever see.

However in the world of camera journalism and marketing, it's the sort of thing that can certainly make a product look less attractive. Particularly for professionals, who like maximum control over their camera, or users with specialized requirements where mandatory NR may have an impact on their image output.
Forum: Pentax K-1 04-16-2018, 11:31 AM  
Pentax K-1 Mark II Early Reviews?
Posted By savoche
Replies: 203
Views: 16,344
Exactly so. The noise amounts to the square root of the signal. While that means that you actually have more noise with more light, the noise makes up a much smaller fraction of the total (signal+noise) than when there are fewer photons captured. If you capture 100 times more light you will increase the amount of noise only 10 times.

Or to look at it in another way; it's not high ISO that gives you noisy images, it's the lack of light. (But yes, when you increase the ISO you will let in less light to avoid overexposure. So in practical terms high ISO gives more noise.)
Forum: Troubleshooting and Beginner Help 04-25-2018, 08:44 AM  
M42 Embarrassment
Posted By Kozlok
Replies: 32
Views: 1,201
That’s why I always remove the retaining clips.
Forum: Digital Processing, Software, and Printing 04-22-2018, 08:29 AM  
How "pure" can a Raw file be?
Posted By stevebrot
Replies: 22
Views: 882
In theory, the RAW data represents voltages for each photo site on the sensor. "Pure" RAW would be these data as captured. "Not-so-pure" would be stuff like using the image processor for removing statistical outliers (probable noise), detection/mitigation of clipped values, and revising voltages to accommodate changes made, all before packaging the data and writing the file.


Steve
Forum: Pentax K-1 04-15-2018, 11:45 AM  
Pentax K-1 Mark II Early Reviews?
Posted By photoptimist
Replies: 203
Views: 16,344
There seems to be some confusion because I think we are talking about the same definition of superresolution
Many people use the term pixels interchangeably with sensels and in many cases the distinction isn't important. The distinction can be important if the sensels are smaller than the pixels (a common property of older sensors) or if the output pixels are at a different resolution than the input sensel data.

It's worth noting that the K-1 only has 9 million red sensels, 18 million green sensels, and 9 million blue sensels. If we want 36 million RGB pixels, we either have to interpolate (blurry!) or get more sensel data using superresolution techniques in which the sensels are not coincident at the color level.

All that is required may be different from what is possible.

But Ricoh does target increased spatial resolution that exactly what pixel shift is for. A single shot K-1 image only resolves to 9 million locations in the red channel. Pixel shift collects multiple frames with the sensels offset to be non-coincident to create 36 million pixels of resolution from the 4 frames of 9 million red values each. Ditto blue and ditto green. That's a superresolution process.



Photoacute explicitly says: "The first step is to accurately align individual low-resolution images with sub-pixel precision."

They also say: "Uncertainty in real registration offsets of individual images. Since the precise camera position and orientation in space is not known during super-resolution processing, it has to be estimated from the low resolution scenes themselves, which introduces errors."

This is untrue in the case of Pentax camera which does have data on the camera position and orientation in space through the SR sensors. You may choose to disbelieve what Ricoh have said about the system but it doesn't make much sense for them to lie about such an arcane element of the system.
Forum: Pentax K-1 03-29-2018, 08:17 AM  
Pentax K-1 Mark II Early Reviews?
Posted By JPT
Replies: 203
Views: 16,344
I think you've made the wrong inference from the photos. What is "Pixel Shift" in English, has always been called "Real Resolution" in Japanese. I remember hearing this from the very first presentation of it.

Here is the FAQ for the K-3 II. Look at Question 3.
English: PENTAX K-3 II | FAQ | Support | RICOH IMAGING
Japanese: PENTAX K-3 II|???????FAQ|????&???? | RICOH IMAGING

This page of the K-1 mark 2 product description shows something similar.
English: Pixel Shift Resolution System II | PENTAX K-1 Mark II | RICOH IMAGING
Japanese: (リアル・レゾリューション = "Real Resolution" transliterated) ?????????????????II / PENTAX K-1 Mark II / ??????? / ?? | RICOH IMAGING

I don't have a Pixel Shift capable camera, but my hunch is that if the interface language is changed to Japanese, it will show "Real Resolution".

Of course, none of this says anything about how it works. Actually, it sounds like a trademark issue to me. I personally prefer naming that alludes to the objective rather than the means, so I tend to prefer "Real Resolution".
Forum: Pentax News and Rumors 02-28-2018, 05:25 PM  
"PENTAX K-1 II with a newly designed Cross Tilt Flexible LCD Monitor"...wait, what?
Posted By clackers
Replies: 32
Views: 3,179
Yes, very reminiscent of Giant Woman promoting the K-S1:

Forum: Pentax News and Rumors 02-23-2018, 12:17 PM  
Looks like the K-1II is Official
Posted By photoptimist
Replies: 117
Views: 8,654
Ricoh's description of the system seems to imply that it is much more than just Rawtherapee on a chip. They are using SR system data in ways not used on the K-1 and not available to Rawtherapee.

I doubt the K-1 in pixelshift mode puts out all the SR system data that the K-1ii is using to do dynamic pixelshift. At the very least, the K-1 is unlikely to store SR system data with the pixelshift Raws because SR is disabled on the K-1 during pixelshift. It's also possible (and seems likely to me) that the SR system sensors on the mainboard have been upgraded for the K-1ii to more accurately measure camera motions over the 0.75+ seconds of a pixelshift exposure set. That suggests that the K-1iI can do things that the K-1 + Rawtherapee cannot.

This issue of in-camera processing versus post-processing is very interesting and does not have any obvious answers. On the one hand, post processing can use much more sophisticated and time-consuming algorithms running on a much more powerful computing platform. But, on the other hand, in-camera processing has much more access to internal data about the sensor, system conditions, lens, and SR sensor measurements. The issue also affects whether post-processing can replicate the noise-surpression offered by the accelerator unit. Whether brute force post-process computing can replicate the benefits of more internal data is not obvious.
Forum: Digital Processing, Software, and Printing 02-03-2018, 09:16 AM  
Adobe Lightroom - Major Performance Boost
Posted By Wheatfield
Replies: 33
Views: 1,539
If the present attitude in the WH had existed back then, rural people would still be using battery operated radios and would be pumping water from wells by hand.
Forum: Monthly Photo Contests 07-03-2017, 07:33 AM  
Sorro...
Posted By Logics
Replies: 15
Views: 813
“Lucky shot”?!?

Getting up early, hiking to the watering hole, positioning yourself relative to the sun, selecting your gear, waiting patiently…. The only lucky thing is that a lion didn't get you. (Unless, of course, this is at a Safari, you just pointed your camera out the window to verify your settings, pushed the shutter release a little too hard, and …voila!)
Forum: Photographic Technique 06-16-2017, 05:25 PM  
Pro Photographers with Amateur Gear vs. an Amateur with Pro Gear
Posted By clackers
Replies: 35
Views: 2,363
But becoming well-versed rather than being gear-obsessed is the point, no?
Forum: Photographic Technique 06-15-2017, 08:33 AM  
Pro Photographers with Amateur Gear vs. an Amateur with Pro Gear
Posted By normhead
Replies: 35
Views: 2,363
Ha, ha, what I've always said. That always get's ignored, or in the case of the above, ridiculed or dismissed.
It's not the camera that makes a pro, it's the creativity with the camera he has.
What determines that to some degree is learning how to use the camera he/she has selected, well enough, that whatever limitations it may have don't get in the way of creativity.

This test displays what a lot of folks here are avoiding like the plague. Good photographers can take compelling images with the gear you own. Buying the gear they own won't help you.

And the main feature there is, he/she knows the camera well enough that whatever it's limitations, they don't get in his/her way.That's not about buying this lens or that lens, or this or that body. That's about learning to be creative with what you have.

It's not at all surprising that we already have folks attacking the way the evidence was complied. When the results don't fit your belief system, attack the way the test was done. It's a strategy used by folks who have nothing except that what they believe says the evidence can't be right. Unfortunately in the greater world, your beliefs affect only you. They are pretty much irrelevant to anyone outside your skin. Where as evidence can be appreciated by anyone. I hate seeing folks crippled by their own belief systems, but what are you going to do?

When they see a great picture, it would seem many want to know about the gear. I always want to know about the photographer. Images that rely on the technical, rather than creative shooting are almost always at best interesting but faddy, at worst, just un-interesting and boring.
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