[normhead]

I definitely need to see some measurement to support these claims. The theory is nice. What's the practice like? Enquring minds want to know. Personally, I usually find the theory of even Pixel shift to be more enticing than the practical advantage it provides. With things like stacking, that require even more effort, I want to see some meaningful improvement in controlled test images before I agree is does anything useful.

IF we are talking "going for the best possible image, we need to compare stacked Pixel Shifted images to ordinary stacked images. It's just misrepresentation to leave out a Pentax step just because it's competitors down't have it. And that is in fact the big question for Pentax users. "If I'm going to stack, is it better to Pixel Shift first?"

Which I answer by noting "My regular images are very good without stacking or pixel shift." But then, I'm talking real situations, not some bogus "theory of how to make up for your camera's lack of Pixel shift."

OK, honest question here, for mee and Ian. "How many of these stacked images do you have?"
Was the process worth it in terms of increased IQ, on your real world examples (which are conspicuously absent from your postings.)

I'm always suspicious of people who recommend processes they don't use over the tried and true.

I have 19 keepers in my Pixel Shift Folder....




Slideshow, click here.

I'd be interested to see what you guys have done with stacking. And I've had a camera with Pixel shift for 3 months. What's your stacked output like? Stacking software has been around for years.

I'd hate to think you guys are just blowing smoke about a process you haven't actually evaluated. Many of us here have evaluated Pixel Shift.

---

Last edited by normhead; 02-04-2017 at 09:19 AM.

[Rondec]

HDR is different from photo stacking. I guess the question in my mind is how can cameras create a single exposure that captures the most dynamic range, most accurate color, and lowest noise in a single, fairly neutral file. The Pentax pixel-shift is one option, although there are others out there.

Once you get into post processing options, there is no particular reason that you would need a D820 or even a D810, as any camera is capable of taking multiple shots and then you can do whatever you want with them post facto. I guess nice to know for Nikon and Canon shooters, but neither here or there with regard to whether you should buy a D820 (or will it be a D850?) over a current production D810.

[normhead]

Technically, Pixel shift shifts the sensor so you have an honest RGB and luminance reading from each pixel site. With image stacking you are still relying on an interpretation of a bayer array. It's not exactly the same, and is impossible using any process I know of on a camera with a fixed sensor to do what Pixels shift does. The closest would be a Foveon sensor.

And as i said, you can stack Pixel Shifted images and still come out on top.

Let's keep this straightforward and factual.

[biz-engineer]

And as i said, you can stack Pixel Shifted images and still come out on top.

I've compared stacking and pixel shift to single frame image quality. Stacking provide a mean to average noise out, but with regard to sharpness, I could never get stacked images as sharp as the pixel shifted ones. Stacking, at best, gives you the same resolution as a single shot, not more.

I would stack 8 frames and increase sharpening, than I'd get something similar to a pixel shifted image in terms of resolution, but... I can also sharpen the pixel shifted image. In the end, the pixel shifted image is still ahead of the stacked image.

---

Last edited by biz-engineer; 02-04-2017 at 11:16 AM.

[normhead]

I've compared stacking and pixel shift to single frame image quality. Stacking provide a mean to average noise out, but with regard to sharpness, I could never get stacked images as sharp as the pixel shifted ones. Stacking, at best, gives you the same resolution as a single shot, not more.

Nice to hear from someone who has first hand knowledge.

[Ian Stuart Forsyth]

I definitely need to see some measurement to support these claims. .

Blind taste test which is taken with pixel shift, single image and photostacking? If there is a difference it should be easy to spot.

Now it gets a little tougher which is the 645z, pixel shift and the photostacking?



---------- Post added 02-05-2017 at 02:59 AM ----------

Which I answer by noting "My regular images are very good without stacking or pixel shift." But then, I'm talking real situations, not some bogus "theory of how to make up for your camera's lack of Pixel shift."

I was wondering how long it would take you to post some low res images



Handheld stack of 4



Tripod



Take 7-10 photos, go home and pick the best for stacking, load them into software, click 4 buttons, go pour a cup of coffee come back to a DNG file waiting from me that can be loaded in any raw converter
I can use any color profiles for the DNG file or make anyone of my own that I made for my own tastes for difficult lighting

https://photos.smugmug.com/Temp/Temp/i-xKdDQfr/0/O/_1710348%20as%20Smart%20Object-1.jpg

Here is a photostack of the the K7 sensor , you can see the individual photosite and also make out some of the RBG in them

---------- Post added 02-05-2017 at 03:18 AM ----------

Um yes! The D5 and 1Dx MkII do 14 fps. The sensor technology is clearly the limiting factor, not flapping the mirror.

Data the limiting factor, I know with the D800 with a hack you can get I think 6 fps at full 36mp resolution.

---------- Post added 02-05-2017 at 03:25 AM ----------

Stacking is limited, at a certain point, decreasing noise levels does not increase dynamics range at all, because the 14 bits A/D can't code more than 14bits.
At ISO100, the noise is already low, 4 stacked shots decrease read noise essentially, beyond that 4x averaging of the Pentax pixel shift, there is no gain of DR.
Beyond averaging, the only way to increase dynamic range is exposure bracketing.

Most people don't use the deepest part of the DR allotted to you by the sensor, the DR I am after is where I use it the most in the 1-5 stop pushing if I can push a shadow area and have it appear 1 stop cleaner then I have hit gold.

[biz-engineer]

Take 7-10 photos, go home and pick the best for stacking, load them into software, click 4 buttons, go pour a cup of coffee come back to a DNG file waiting from me that can be loaded in any raw converter I can use any color profiles for the DNG file or make anyone of my own that I made for my own tastes for difficult lighting

The K1 does it in camera, real time, that mean it does not clog the buffer, K1 firmware take the new DNG and average it out with the last averaged DNG that resides in memory; processed as a background task. You shoot a stack with K1, you get 1 single RAW DNG on the SD card. You can even stack 200 x 14bits x 36Mpixels shots if you like; there is no buffer limit. And so, you don't need to: "go home and pick the best for stacking, load them into software, click 4 buttons, go pour a cup of coffee come back to a DNG file waiting from me that can be loaded in any raw converter I can use any color profiles for the DNG file or make anyone of my own that I made for my own tastes for difficult lighting".

But wait, you gonna say "What if one of the stacked RAW was blurred and messed up the stack?". Well, on the K1 you can also check mark an option which is "Save process" , that means the K1 firmware does the real time stacking on a single raw, and also saves each RAW on the SD card. So, when you arrive home, you take the DNG already prepare by the camera for you, AND if you are not happy, you can ALSO do the complicated NIKON way.

Understood? :-)

---------- Post added 05-02-17 at 11:50 ----------

P.S. the downside of stacking with the K1 is that you don't have time for a cup of coffee, the stacking is finished before you even have a chance to reach the cup.

---

Last edited by biz-engineer; 02-05-2017 at 03:48 AM.

[D1N0]

Why do people want to shoot full frame when they can just stitch a few aps-c images Maybe because it is a hassle.
Anyway pixel shift is not just stacking. It shoots a red, green and blue exposure and combines those, avoiding de-mosaicing. This is why the images are much cleaner and sharper. It is a more elegant method than averaging out noise in a stack. And as norm says, you could still stack a number of pixel shifted images. They are different methods. Olympus already uses a stacking algorithm in the camera. It takes eight shots while shifting the sensor half a pixel each time. You can get no such precision on a non IBIS camera. It Think the Pentax method with 3+1 shots is better. I theory Pentax could stack 8 images of each color and then combine them and see what happens.

[normhead]

I'm not sure exactly what Ian is doing up there.

If you want something done, do it yourself.

Anyway apples to apples.

Pentax PS image and Nikon D810 image at base ISO. And that would be consistent with my own experience. At Base ISO it's 50/50 which images is better, the PS image or the single image.





Not much to choose from. Different focal points have been used. The Nikon looks cleaner on the fabrics, on the top of the left most bottle the detail in the black is superior in the Pentax. Both images are better than the D800e image I prepared.

Personally, I find PS hit and miss. I have seen no images demonstrating stacking does anything for any well exposed photo either. As far as I understand it stacking is used to create more DoF, in very shallow DoF images, macros etc.

SO, personally, I'm not sold on the need for either PS or stacking. With my own comparisons, sometimes the PS image is better, sometimes the single frame image is better. But, it is definitely easier to use PS, than it is to stack. Meanwhile the low light effects of reducing noise in high ISO image using PS is really well documented on the Imaging Resources site, especially on images that are pretty much totally unusable anyway.

I'll try Pixel Shift because it's cheap and dirty. Stacking, not so much.

I have no idea what effect stacking would have on these images but out of the camera, the PS image absolutely wipes the floor with the D810 image at 25600 ISO, if you're interested in that kind of thing. Personally I tend to shoot at more favourable ISOs where it would seem to make less difference. But somewhere between base ISO and 25600 ISO Pixel shift starts to make a noticeable difference.


I absolutely refuse to say stacking could clean up that D810 image, until I see it. That would be simply irresponsible.

SO I have to ask, is there one photo or series of photos out there that shows stacking can produce anything similar to the type of improvement Pixels shift can or is this just some kind of wild speculation?


At 3200 ISO which I actually use on the K-1 IR managed to miss focus on both K-1 images. But you can still see the Pentax noise advantage, so basically, $1000 cheaper, for in the end pretty much identical performance at useable ISOs and considerably better performance at ultra-high ISO. Not too shabby.

[ffking]

I detect a bit of camera preference prejudice taking place here. Prejudice in the sense of pre-judging. NO facts will be accepted unless Nikon comes out ahead of Pentax. And if Pentax has an advantage, Nikon users can work around it. I see how this works.

wouldn't it be lovely if we could all just accept that all cameras and brands have strengths and weaknesses, and all you have to do is look for the brand and model that best suits your shooting preferences then go out and take photographs with it: If you can't afford to change brands, then take the type of images tat your camera does well, or do work-arounds. If you can't find work-arounds, save up, or get a different hobby. But don't endlessly complain -every manufacturer is doing their best against to navigate scores of competing priorities, and they all make pretty remarkable products. We need them all. It's that simple

[mee]

wouldn't it be lovely if we could all just accept that all cameras and brands have strengths and weaknesses, and all you have to do is look for the brand and model that best suits your shooting preferences then go out and take photographs with it: If you can't afford to change brands, then take the type of images tat your camera does well, or do work-arounds. If you can't find work-arounds, save up, or get a different hobby. But don't endlessly complain -every manufacturer is doing their best against to navigate scores of competing priorities, and they all make pretty remarkable products. We need them all. It's that simple

I think a bigger issue is people (not you) coming into threads to defend Pentax, completely missing the point of the discussion, and then introducing their own zero sum, us vs them argument to try to change the course of the discussion.. when it was really friendly beforehand and the 'door breaching' was entirely unnecessary (esp when we're in the deemed Non-Pentax section).

[normhead]

I think a bigger issue is people coming into threads to defend Pentax, completely missing the point of the discussion, and then introducing their own zero sum, us vs them argument to try to change the course of the discussion.. when it was really friendly beforehand and the 'door breaching' was entirely unnecessary.

And now we have finger pointing... what an improvement.

I guess you see nothing at all controversial in the following statements.

I'm seriously eyeballing both the 750 and the 810 in the next 6 months depending on what Ricoh show for a K-3 II replacement and where used K-1 prices sit.

It seems used Canikony are a better value as the 'newer' lens selection is both abundant and cheap.

One can buy a refurb D750 and a refurb 24-120 f/4g for the same price of a new K-1 body.

But, as someone who just wants a decent FF experience, which one do you think they'll buy? I think they'll more buy the used Canikony if they know it is an option.

Do you honestly think that kind of anti-Pentax bias is friendly?

The above statements would appear to be those of an extremely biased Canikon lover, not at all interested in any serious discusion of the facts, and probably only friendly to those who share his opinions, which are nothing more than statements of bias.

If you want to know how this thread got into Pentax vs. Nikon, there it is. Started by the Nikon lover. And continued by another Nikon lover. And then you have the nerve to claim Pentax users are infiltrating the thread defending Pentax. Ask yourself,
Why was I so negative about Pentax." It's you dude. You and Ian, not the Pentax folks. What did you think this was just some kind of secret place where you could sit and bash Pentax to your hearts content?

[mee]

And now we have finger pointing... what an improvement.

I guess you see nothing at all controversial in the following statements.







Do you honestly think that kind of anti-Pentax bias is friendly?

The above statements would appear to be those of an extremely biased Canikon lover, not at all interested in any serious discusion of the facts, and probably only friendly to those who share his opinions, which are nothing more than statements of bias.

If you want to know how this thread got into Pentax vs. Nikon, there it is. Started by the Nikon lover. And continued by another Nikon lover. And then you have the nerve to claim Pentax users are infiltrating the thread defending Pentax. Ask yourself,
Why was I so negative about Pentax." It's you dude. You and Ian, not the Pentax folks. What did you think this was just some kind of secret place where you could sit and bash Pentax to your hearts content?

Non-Pentax Cameras: Canon, Nikon, etc. forum is a place for such discussion without the annoyance of people like you coming in with a Pentax fanboy agenda... just please leave us be.

[normhead]

Non-Pentax Cameras: Canon, Nikon, etc. forum is a place for such discussion without the annoyance of people like you coming in with a Pentax fanboy agenda... just please leave us be.

You don't have the right to keep me out of any thread. You do have the right to be a decent human being.

I came here to see what the latest buzz was on the latest Nikon body. Instead I got the same old Pentax bashing nonsense you always post.

I come to this site because I'm a Pentax shooter, and it's full of Pentax advice plus a smattering of info about other brands. I do not come here to bash Nikon. In fact, I'm convinced, if I was a Nikon shooter, I'd be a happy Nikon shooter, if I was a Canon shooter I'd be a happy Canon shooter. I have faith in my ability to get along which ever way I go. I have no use for folks like yourself who get into brand bashing whenever an opportunity presents itself.

It's not me that needs to leave it alone. And honestly if I was on a Nikon forum and someone was bashing Nikon the way you bash Pentax, I'd put my hand up and say "Wait a minute here, let's look at reality." Just like I do with you here. I don't buy the "I have to buy a Nikon or I have to buy a Canon of I have to buy a Pentax" nonsense. What you have to do is learn to take photographs so you actually get experience with the equipment you're talking about.

I hate it when folks talk crap about any brand. I treasure the informed.

I simply do not understand folks who say "I have to have this brand, or I have to have that brand". It's all non-sense.
Now if someone wants to say, I really like the way Canon tethering works, and Pentax isn't as good. That's not brand bashing. Thats sharing info about superior technology. I probably shoot Pentax because it suits my style, and because it's what I started with, but that's not a knock on any other camera company. That's because I could shoot anything and be happy. Where as folks like you seem to be unable to be happy with anything.

[BigMackCam]

Folks, please - no more arguing, finger pointing, calling each other rude and annoying.

Any further posts along these lines will be deleted and the relevant members (all involved) banned from the thread. Any more after that, and I'll have to close the thread.

Thanks in advance