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06-10-2018, 10:31 AM   #46
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QuoteOriginally posted by Wild Mark Quote
Here you are saying that the native 36MP sensor is not actually 36MP, but with pixel shift it becomes a real 36MB.
Yes, that is what he is saying and what I was saying and sort of not what you were saying.

QuoteOriginally posted by Wild Mark Quote
I suspect the effective pixel density is much greater than the physical sensor.
This is what you were saying ^ ^ ^ .

I am familiar with the original PF article explaining PS resolution and the particular paragraph postulating a favorable comparison to higher resolution sensors. I don't know that the comparisons have actually been done, but it would not surprise me if detail capture were on the same order as cameras with significantly higher pixel resolutions. Though that would not be the same as higher effective pixel density and I don't believe the authors make that claim, mostly because what we are talking about is higher per pixel fidelity, not more detail per pixel.*

For normal Bayer extrapolation the effective pixel density** is significantly less than the physical sensor's specification. It is a small difference in logic, but one supported by example photos*** such as one where most of the small red berries on a bush magically disappear from a digital capture, but are present on film images scanned and rendered to the same pixel resolution. Actual pixel densities in the digital versions are the same for both images, but nobody would claim that the scan has higher effective pixel density just because the film got better data. The pixels generated from the sensor output were simply deficient by design. Pentax's Pixel shift makes up for much of that deficiency such that each rendered pixel is simply more accurate to reality. Would "pixel efficiency" (as a percentage of ideal) be a reasonable term?


Steve

* Sorry to be pedantic, but sensors don't really have pixels. They have photo-detector sites whose readings are interpreted by code to create digital representations of pixels; pixels themselves being, after all, a logical representation of a spot of light and nothing more (i.e. a pixel has no detail).

** I am unfamiliar with the term and Google was no help, at least in regards to digital capture. I take it to mean that one might treat a PS image to the same effect as if it had more pixels than are actually there.

** The example I cited is from the infamous film vs. digital shoot-out conducted by PetaPixel a few years ago where the Canon 5D II showed an appetite for rowan berries. LINK


Last edited by stevebrot; 06-10-2018 at 10:39 AM.
06-10-2018, 03:37 PM   #47
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Pixel efficiency

QuoteOriginally posted by stevebrot Quote
Yes, that is what he is saying and what I was saying and sort of not what you were saying.



This is what you were saying ^ ^ ^ .

I am familiar with the original PF article explaining PS resolution and the particular paragraph postulating a favorable comparison to higher resolution sensors. I don't know that the comparisons have actually been done, but it would not surprise me if detail capture were on the same order as cameras with significantly higher pixel resolutions. Though that would not be the same as higher effective pixel density and I don't believe the authors make that claim, mostly because what we are talking about is higher per pixel fidelity, not more detail per pixel.*

For normal Bayer extrapolation the effective pixel density** is significantly less than the physical sensor's specification. It is a small difference in logic, but one supported by example photos*** such as one where most of the small red berries on a bush magically disappear from a digital capture, but are present on film images scanned and rendered to the same pixel resolution. Actual pixel densities in the digital versions are the same for both images, but nobody would claim that the scan has higher effective pixel density just because the film got better data. The pixels generated from the sensor output were simply deficient by design. Pentax's Pixel shift makes up for much of that deficiency such that each rendered pixel is simply more accurate to reality. Would "pixel efficiency" (as a percentage of ideal) be a reasonable term?


Steve

* Sorry to be pedantic, but sensors don't really have pixels. They have photo-detector sites whose readings are interpreted by code to create digital representations of pixels; pixels themselves being, after all, a logical representation of a spot of light and nothing more (i.e. a pixel has no detail).

** I am unfamiliar with the term and Google was no help, at least in regards to digital capture. I take it to mean that one might treat a PS image to the same effect as if it had more pixels than are actually there.

** The example I cited is from the infamous film vs. digital shoot-out conducted by PetaPixel a few years ago where the Canon 5D II showed an appetite for rowan berries. LINK
Perhaps pixel efficiency is a better term but ‘effective pixel density’, as I termed it, has the same meaning. what about ‘enhanced sensor performance’ ........ choice of word I guess

We all know PS results in a single frame composed from the data of four images. Each image is moved ever so slightly to gain a differing perspective of the same scene. In so doing the composite frame has replaced interpolated data with real data measured from the same sensor. This effectively increases the number of recorded data points for the same sensor area.

The point I was making remains the same. My use of language is dissimilar to yours and using a google search to invalidate my use of language is, well, a distraction. Below is an extract from the article that exemplifies this point;

“This effectively quadruples the number of red/blue pixels and doubles the number of green pixels, increasing the overall level of recoverable detail in the final processed image. ”

You can see from this sentence how one can grab the words ‘effective’ and ‘pixel’ and deduce the word ‘density’ (quadruples/ doubles).

God forbid the emergence of a modern day Shakespeare to rival the supremacy of google.
06-10-2018, 04:05 PM   #48
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Of course handheld macro is tough. I am not sure many people could hold the camera without too much shake.
06-10-2018, 06:12 PM   #49
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QuoteOriginally posted by swanlefitte Quote
Of course handheld macro is tough. I am not sure many people could hold the camera without too much shake.
With the right lighting such as ring flash you can easily shoot f11 to f16 with a shutter speed of 125-200. With natural lighting I agree - hand held is tough as depth of field/ noise from higher iso start to impact your image

06-10-2018, 06:25 PM   #50
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QuoteOriginally posted by Wild Mark Quote
With the right lighting such as ring flash you can easily shoot f11 to f16 with a shutter speed of 125-200. With natural lighting I agree - hand held is tough as depth of field/ noise from higher iso start to impact your image
I do it all the time but not to get 4 shots off. 1 will be moved forward out of focus next to the left out of frame and one tilted. Even when I wait till I feel still and breath out and roll my finger over the shutter I still miss alot.
06-10-2018, 08:26 PM   #51
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QuoteOriginally posted by swanlefitte Quote
I do it all the time but not to get 4 shots off. 1 will be moved forward out of focus next to the left out of frame and one tilted. Even when I wait till I feel still and breath out and roll my finger over the shutter I still miss alot.
Yes I share in the breathlessness when shooting macro hand held. I am hoping the handheld PS will enhance the macro shots without to much change to the macro shooting method. We shall see.
06-11-2018, 01:13 AM   #52
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QuoteOriginally posted by swanlefitte Quote
Of course handheld macro is tough. I am not sure many people could hold the camera without too much shake.
I do it routinely with butterflies in the summer.
If you are in direct sunlight, in August, where I live, there's plenty enough light to get reasonable, hand-holdable speeds.
Plus, you can use a flash with a diffuser, and if its contribution is comparable to available light, and the angle different, you won't get much of the "straight-on blaze" effect the on-camera flash is (in)famous for. With flash you can of course hand-hold anything.

I'll try to post some pictures as soon as I can.
06-11-2018, 05:49 AM - 1 Like   #53
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QuoteOriginally posted by LensBeginner Quote
There you go, I took the liberty of practicing what I preached!
Due credit is given, of course.
And it's another small bit towards the month's quota... I'm just dying to get that K-1...
Remember it's an A5 sheet, not A4! So 148 x 210 mm
Nice! Credit wasn't required on such a simple idea, but I absolutely appreciate it.

QuoteOriginally posted by LensBeginner Quote
I do it routinely with butterflies in the summer.
See the next post by swanlefitte... he's referring to handheld macro pixelshift. I understand pixelshift takes a certain minimum amount of time between shots, that might make the gains over a traditional 1-shot photo diminish when hand holding at higher magnifications as slight drifts or tilts can quickly be too much between photos for the camera to compensate.

Single shot, handheld macro is certainly do-able in the right ambient lighting conditions and with suitable expectations.

06-11-2018, 06:00 AM - 1 Like   #54
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QuoteOriginally posted by BrianR Quote
*snip*

See the next post by swanlefitte... he's referring to handheld macro pixelshift. I understand pixelshift takes a certain minimum amount of time between shots, that might make the gains over a traditional 1-shot photo diminish when hand holding at higher magnifications as slight drifts or tilts can quickly be too much between photos for the camera to compensate.

Single shot, handheld macro is certainly do-able in the right ambient lighting conditions and with suitable expectations.
Ah sorry I was missing context.
Well, many reviewers can't find much gain in HHPS anyway, and in "fringe" scenarios like macro I suspect one would be better of doing a burst (if flash isn't an issue) and, if need be and the images can be properly aligned, do a super-resolution stack on a PC. Otherwise, you just select the best one and that's it.
Those butterflies were pumping nectar so furiously with their proboscis, shaking it so madly, that any kind of burst would have resulted in markedly different poses and thus stacking issues.
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