[OT]:: 4K Video

Russell, Russell, Russell...

Come on - you've been in this circus long enough to see through this hype.

When they announce the 16K (or maybe the 64K) - then and only then
should you be looking for bargains in the 4K realm. Do you *really*
think that 4K monitors are going to improve your photo viewing
experience? Hi-res printers? Yeah, monitors - not so much.

Post by RussellMc
Sought: Comments & recommendations on acceptable performance low-cost
entry-level 4K capable video cards for "desktop" applications.

RussellMc

2014-05-17 01:27:12 UTC

Post by Marcel Duchamp
Russell, Russell, Russell...
Come on - you've been in this circus long enough to see through this hype.

Alas, I've been in the business of looking at photos on screen long enough
to know that a "higher res" monitor will in fact so a better job of doing
what I want to do.

Most people have some photos that they have taken.
Some people have many ...
A few people ...

I have no easy way to be sure of how many of my own photos I have (I'm
working on it) but on my ~= 30 TB of E F G I J K L M O P R S T drives I
have 6.6 million JPGS, mainly my own photos. These are duplicated at least
once each (hopefully) and sometimes 3 or 4 times and there are downsized
derivatives and subsets and ... .
I estimate photos taken to be in the 500,000 to 1,000,000 range.
SO I've looked at a fair few photos and know what I'd like in a monitor.

My main monitor is a Dell 2709W 27" native at 1920 x 1200 (slightly above
1080P).

My main camera produces 6000 x 4000 pixel images.
So when viewed pixel per pixel I get 111920/6000 = 32% of the image
horizontally and 1200/3000 = 40% of the image vertically - so about 13% of
the total image overall.
If I scale the image 50% linearly to 3000 x 2000 I''d get about 50% on
screen areally (<- Google spell checker knows this) AND on a 4K screen it
would more than fit.
On a 4k screen my 6000 x 4000 images still do not fit pixel per pixel.

8k (said to be liable to be mainstream by 2032) will display 6000 x 4000
natively.

Does it matter?.
More or less no, but "it's nice".
My Dell (essentially full HD) allows viewing of most relevant detail for
most purposes when editing.
It is seldom that I feel the need to expand and image to get better
resolution perception when adjusting colour balances or tonal curves or
similar.
Exceptions MIGHT be things like nuances of colour or shading on things like
a bride's veil.

For various reasons I try to avoid editing of subjects-proper (backgrounds
may be fair game on occasion to remove distractions etc) so high resolution
for editing is largely not an issue and is well enough served by either
pixel per pixel display or some intermediate zoom state.

4K http://en.wikipedia.org/wiki/4K_resolution

8K http://en.wikipedia.org/wiki/8K_resolution

Post by Marcel Duchamp
When they announce the 16K (or maybe the 64K) - then and only then
should you be looking for bargains in the 4K realm. Do you *really*
think that 4K monitors are going to improve your photo viewing
experience?

As above.
8k will do for 24 Mp sensors.

Post by Marcel Duchamp
Hi-res printers?

Delving into the world of colour resolution produces some surprises.
No references here but I have some.
Colour resolution in pictures need be no higher than 200 dpi in almost all
cases and 300 dpi monochrome.
There are good reasons for this and all the usual expert arguments.
But, say 300 dpi on A3 = 16" x 10" = 4800 x 3000 (14.4 Mp)
That's slightly above 4K and well inside 8k.
A4 = 3000 x 2400 = just over 4K due to vertical being a bit small.

So, yes, I'd "like" a 4K monitor.

Russell

John Guillory

2014-05-17 03:42:46 UTC

Just curious, but what is the dot pitch of your eyes, and are they factory standard, or have you replaced them with new improved eyes? Just wondering, because someone said the reason Apple has such a pathetic camera is because the human eye isn't capable of perceiving anything better.

--
KF5QEO
John Guillory
***@yahoo.com
Cell: 601-754-9233
Pinger: 337-240-7890
Google Voice: 601-265-1307

Post by Marcel Duchamp
Russell, Russell, Russell...
Come on - you've been in this circus long enough to see through this hype.

Alas, I've been in the business of looking at photos on screen long enough
to know that a "higher res" monitor will in fact so a better job of doing
what I want to do.
Most people have some photos that they have taken.
Some people have many ...
A few people ...
I have no easy way to be sure of how many of my own photos I have (I'm
working on it) but on my ~= 30 TB of E F G I J K L M O P R S T drives I
have 6.6 million JPGS, mainly my own photos. These are duplicated at least
once each (hopefully) and sometimes 3 or 4 times and there are downsized
derivatives and subsets and ... .
I estimate photos taken to be in the 500,000 to 1,000,000 range.
SO I've looked at a fair few photos and know what I'd like in a monitor.
My main monitor is a Dell 2709W 27" native at 1920 x 1200 (slightly above
1080P).
My main camera produces 6000 x 4000 pixel images.
So when viewed pixel per pixel I get 111920/6000 = 32% of the image
horizontally and 1200/3000 = 40% of the image vertically - so about 13% of
the total image overall.
If I scale the image 50% linearly to 3000 x 2000 I''d get about 50% on
screen areally (<- Google spell checker knows this) AND on a 4K screen it
would more than fit.
On a 4k screen my 6000 x 4000 images still do not fit pixel per pixel.
8k (said to be liable to be mainstream by 2032) will display 6000 x 4000
natively.
Does it matter?.
More or less no, but "it's nice".
My Dell (essentially full HD) allows viewing of most relevant detail for
most purposes when editing.
It is seldom that I feel the need to expand and image to get better
resolution perception when adjusting colour balances or tonal curves or
similar.
Exceptions MIGHT be things like nuances of colour or shading on things like
a bride's veil.
For various reasons I try to avoid editing of subjects-proper (backgrounds
may be fair game on occasion to remove distractions etc) so high resolution
for editing is largely not an issue and is well enough served by either
pixel per pixel display or some intermediate zoom state.
4K http://en.wikipedia.org/wiki/4K_resolution
8K http://en.wikipedia.org/wiki/8K_resolution

As above.
8k will do for 24 Mp sensors.

Post by Marcel Duchamp
Hi-res printers?

Brent Brown

2014-05-17 04:31:42 UTC

I don't know if my eyes are any better or worse than Russells - but I was impressed
when I first saw a .GIF of a parrot at 320 x 200 pixels 256 colours on a CGA CRT
monitor. I remember thinking it was so realistic and I couldn't easily distinguish the
pixels, surely that would be enough colours and pixels for any photo. Wait, I still
have the .GIF... but it's 57kb, probably too big to post.

Post by John Guillory
Just curious, but what is the dot pitch of your eyes, and are they
factory standard, or have you replaced them with new improved eyes?
Just wondering, because someone said the reason Apple has such a
pathetic camera is because the human eye isn't capable of perceiving
anything better.

John Guillory

2014-05-17 06:47:43 UTC

Yeah, I had that parrot …. Used to be used for selling monitors. But 256 colors at 320x200 is one thing, and millions of colors at 6000x6000 or so resolution is another thing. I should generate a few test videos. Set it to 5000x5000 resolution, and generate 4 dots comprised of 1 pixel each. Randomly move each dot at random times. You keep track of each time you see a dot move. Let me know how many times each dot moves. Now we test your color ability. 200 dots of random colors will be displayed. Keep track of how many times each of the 200 colors moved. Finally we fill the screen with 25000000 different colored pixels. You have 2 minutes to let me know how many unique colored pixels you see. One last test. This should be much easier. Fill the screen with random dots, but each dot will be either pure white or pure black. All you have to do is tell me is how many white dots, how many black dots, which color had the most dots, and by what percent more. Pretty simple, but I'll give you 5 minutes to compose your thoughts on this one...

--
KF5QEO
John Guillory
***@yahoo.com
Cell: 601-754-9233
Pinger: 337-240-7890
Google Voice: 601-265-1307

Post by Brent Brown
I don't know if my eyes are any better or worse than Russells - but I was impressed
when I first saw a .GIF of a parrot at 320 x 200 pixels 256 colours on a CGA CRT
monitor. I remember thinking it was so realistic and I couldn't easily distinguish the
pixels, surely that would be enough colours and pixels for any photo. Wait, I still
have the .GIF... but it's 57kb, probably too big to post.

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Sean Breheny

2014-05-17 05:00:00 UTC

I'm pretty sure that the human eye (assuming no problems with focus) is
diffraction limited in typical indoor lighting conditions, not pixel
resolution (rod/cone density) limited. If the pupil is 4mm in diameter (mid
range), then the diffraction limit would be roughly 1.22*Lamba/diameter or
1.22*500nm/4mm=153 micro radians for 500nm light. If you are sitting at 0.5
meter from your monitor, you can resolve pixels which are 0.000153*0.5=75
microns pitch. For a monitor 0.5meter wide, this would be 6600 pixels
horizontal resolution.

Bear in mind that this calculation depends on how large the monitor is. If
the screen is not very wide then the image will look very good even with a
fairly low horizontal pixel count since the spatial resolution is still
good.

In Russell's case, if his photos are being "blown up" onto a large screen,
then it is very likely that his eyes can tell the difference between, say,
2000 pixels horizontal versus 4000.

Sean

Post by John Guillory
Just curious, but what is the dot pitch of your eyes, and are they factory
standard, or have you replaced them with new improved eyes? Just
wondering, because someone said the reason Apple has such a pathetic camera
is because the human eye isn't capable of perceiving anything better.
--
KF5QEO
John Guillory
Cell: 601-754-9233
Pinger: 337-240-7890
Google Voice: 601-265-1307

Post by Marcel Duchamp
Russell, Russell, Russell...
Come on - you've been in this circus long enough to see through this

hype.

Post by RussellMc
Alas, I've been in the business of looking at photos on screen long

enough

Post by RussellMc
to know that a "higher res" monitor will in fact so a better job of doing
what I want to do.
Most people have some photos that they have taken.
Some people have many ...
A few people ...
I have no easy way to be sure of how many of my own photos I have (I'm
working on it) but on my ~= 30 TB of E F G I J K L M O P R S T drives I
have 6.6 million JPGS, mainly my own photos. These are duplicated at

least

Post by RussellMc
once each (hopefully) and sometimes 3 or 4 times and there are downsized
derivatives and subsets and ... .
I estimate photos taken to be in the 500,000 to 1,000,000 range.
SO I've looked at a fair few photos and know what I'd like in a monitor.
My main monitor is a Dell 2709W 27" native at 1920 x 1200 (slightly

above

Post by RussellMc
1080P).
My main camera produces 6000 x 4000 pixel images.
So when viewed pixel per pixel I get 111920/6000 = 32% of the image
horizontally and 1200/3000 = 40% of the image vertically - so about 13%

Post by RussellMc
the total image overall.
If I scale the image 50% linearly to 3000 x 2000 I''d get about 50% on
screen areally (<- Google spell checker knows this) AND on a 4K screen it
would more than fit.
On a 4k screen my 6000 x 4000 images still do not fit pixel per pixel.
8k (said to be liable to be mainstream by 2032) will display 6000 x 4000
natively.
Does it matter?.
More or less no, but "it's nice".
My Dell (essentially full HD) allows viewing of most relevant detail for
most purposes when editing.
It is seldom that I feel the need to expand and image to get better
resolution perception when adjusting colour balances or tonal curves or
similar.
Exceptions MIGHT be things like nuances of colour or shading on things

Post by RussellMc
a bride's veil.
For various reasons I try to avoid editing of subjects-proper

(backgrounds

Post by RussellMc
may be fair game on occasion to remove distractions etc) so high

resolution

Post by RussellMc
for editing is largely not an issue and is well enough served by either
pixel per pixel display or some intermediate zoom state.
4K http://en.wikipedia.org/wiki/4K_resolution
8K http://en.wikipedia.org/wiki/8K_resolution

As above.
8k will do for 24 Mp sensors.

Post by Marcel Duchamp
Hi-res printers?

Delving into the world of colour resolution produces some surprises.
No references here but I have some.
Colour resolution in pictures need be no higher than 200 dpi in almost

all

Post by RussellMc
cases and 300 dpi monochrome.
There are good reasons for this and all the usual expert arguments.
But, say 300 dpi on A3 = 16" x 10" = 4800 x 3000 (14.4 Mp)
That's slightly above 4K and well inside 8k.
A4 = 3000 x 2400 = just over 4K due to vertical being a bit small.
So, yes, I'd "like" a 4K monitor.
Russell
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Peter Johansson

2014-05-17 05:29:00 UTC

Post by Sean Breheny
Bear in mind that this calculation depends on how large the monitor is. If
the screen is not very wide then the image will look very good even with a
fairly low horizontal pixel count since the spatial resolution is still
good.

John Guillory

2014-05-17 07:01:52 UTC

But if you sit 3" from the screen, a 27" seems more like a wide screen theater!

--
KF5QEO
John Guillory
***@yahoo.com
Cell: 601-754-9233
Pinger: 337-240-7890
Google Voice: 601-265-1307

Post by Peter Johansson

Indeed. 1920x1200 results in some rather fine pixels on a 17" screen,
but those same pixels are rather coarse on a 27" screen. 1920x1200
makes for a very nice 27" TV at TV viewing distances, but those pixels
are way too large for a desktop computer monitor.
-p.
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RussellMc

2014-05-17 05:39:01 UTC

Quick comment - work (manual labour) calls ...

Post by Sean Breheny
I'm pretty sure that the human eye (assuming no problems with focus) is
diffraction limited in typical indoor lighting conditions,

I'll have to look further at your suggestion. It may be useful in a number
of areas. I had not thought of it in those terms (even though I should
have).

Photo viewing , for the excessively serious, is done with low external
light and screen brightness is set by the monitor and user settings.

Max brightness of many LCDs is usually 300-400 lux and usually used will be
lower.

not pixel

Post by Sean Breheny
resolution (rod/cone density) limited. If the pupil is 4mm in diameter (mid
range), then the diffraction limit would be roughly 1.22*Lamba/diameter or
1.22*500nm/4mm=153 micro radians for 500nm light. If you are sitting at 0.5
meter from your monitor, you can resolve pixels which are 0.000153*0.5=75
microns pitch. For a monitor 0.5meter wide, this would be 6600 pixels
horizontal resolution.

or 2000 pixels in 300mm or 2000 pixels on 900 mm wde screen a 1.5 metres.

This page (and similar)

http://www.dpreview.com/reviews/sony-alpha-slt-a99/19

and

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=105&Camera=453&Sample=0&FLI=0&API=5&LensComp=687&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=4

would allow investigations.

There are tools more directed at this. Will look.

More anon.

R

John Guillory

2014-05-17 06:57:45 UTC

Ok, so let's figure up a couple of scenarios of reality.

1. Assume that money is no object, and he has a 30ft by 8ft LCD screen with 16k resolution. He's getting old, and loves the lifelike feel, so he sits 1 ft away from the screen.

2. Money's tight, but his health is sharp! He's spent all his money on massive man cave, so he doesn't have the best monitor. He managed to steal the head rest monitor out of the president's limo. Don't tell anyone, it's 4"x3" 16k resolution hdmi monitor that runs off of 12v dc power. He loves to watch it from his electronics bench that is 20 ft away. Now for the record I probably couldn't even see the tv from that distance, but hey... We'll put the schematic to his project on the screen with 1pt lines and 6pt text. He should have no problem wiring up that project, right?

--
KF5QEO
John Guillory
***@yahoo.com
Cell: 601-754-9233
Pinger: 337-240-7890
Google Voice: 601-265-1307

Post by Sean Breheny
I'm pretty sure that the human eye (assuming no problems with focus) is
diffraction limited in typical indoor lighting conditions, not pixel
resolution (rod/cone density) limited. If the pupil is 4mm in diameter (mid
range), then the diffraction limit would be roughly 1.22*Lamba/diameter or
1.22*500nm/4mm=153 micro radians for 500nm light. If you are sitting at 0.5
meter from your monitor, you can resolve pixels which are 0.000153*0.5=75
microns pitch. For a monitor 0.5meter wide, this would be 6600 pixels
horizontal resolution.
Bear in mind that this calculation depends on how large the monitor is. If
the screen is not very wide then the image will look very good even with a
fairly low horizontal pixel count since the spatial resolution is still
good.
In Russell's case, if his photos are being "blown up" onto a large screen,
then it is very likely that his eyes can tell the difference between, say,
2000 pixels horizontal versus 4000.
Sean

Post by John Guillory
Just curious, but what is the dot pitch of your eyes, and are they factory
standard, or have you replaced them with new improved eyes? Just
wondering, because someone said the reason Apple has such a pathetic camera
is because the human eye isn't capable of perceiving anything better.
--
KF5QEO
John Guillory
Cell: 601-754-9233
Pinger: 337-240-7890
Google Voice: 601-265-1307

Post by Marcel Duchamp
Russell, Russell, Russell...
Come on - you've been in this circus long enough to see through this

hype.

Post by RussellMc
Alas, I've been in the business of looking at photos on screen long

enough

least

above

Post by RussellMc
a bride's veil.
For various reasons I try to avoid editing of subjects-proper

(backgrounds

Post by RussellMc
may be fair game on occasion to remove distractions etc) so high

resolution

As above.
8k will do for 24 Mp sensors.

Post by Marcel Duchamp
Hi-res printers?

Delving into the world of colour resolution produces some surprises.
No references here but I have some.
Colour resolution in pictures need be no higher than 200 dpi in almost

all

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RussellMc

2014-05-17 05:23:34 UTC

On 17 May 2014 15:42, John Guillory <***@yahoo.com> wrote:

(2) > ... someone said the reason Apple has such a pathetic camera is
because the human eye isn't capable of perceiving anything better ...

Would this be the Apple that produces the "Retina" displays aimed at
exceeding perceivable dot pitch at typical viewing distances so that the
eye is well served?

Apple's cameras are OK enough with lots of light. They are not as good as
those in good dedicated cameras because Apple think they can get away with
spending less than that would take. They can use tiny sensors, add lots of
megapixels and the Apple experience and most people's wants are met. 'Most
people' is usually enough. Large sensors require large optics and cost
rises rapidly.

Many of the photos that I take with a DSLR are blurred and/or exposed badly
and/or framed badly and/or ... .
If I used a phone camera most of these ones would not exist at all.
Especially when I travel, the camera is an extension to my arm and, as well
as record of travel, and purposeful quality-directed photos, I also push
the camera beyond its abilities, and then see what I have managed to do
well enough to be worthwhile. Surprised the person who pulls a strange face
or adopts a ridiculous pose for a brief moment in front of my camera as a
challenge to the cameraman. Most are quite amused when shown the photo(s)
that quite often manage to get taken in such moments of levity. 'Good
quality' well-lit well focused photos are always 'nice to have', but SOME
of the best photos manage only some or even none of these.

A top DSLR seems to take photos almost before the shutter button is pressed
- so much so that in unsighted photos from moving vehicles you need to
trail the spot where your brain says the subject is.) A cameraphone or even
OK point & shoots are far too unresponsive for this. [I use them too, but
differently].
___________

(1)

Just curious, but what is the dot pitch of your eyes, and are they factory

Post by John Guillory
standard, or have you replaced them with new improved eyes? Just
wondering, because someone said the reason Apple has such a pathetic camera
is because the human eye isn't capable of perceiving anything better.

My son's comments on getting a 4k monitor included - "This looks to have
more detail than reality - I'm going to stay here inside where it's warm".

I have very normal 'failing with age' eyes.
I wear $2 shop reading glasses BUT carefully chosen to have a diopter
rating to suit screen and viewing distance that I usually use.
Glasses that I carry or wear around tend to have short lifetimes. Very
strange :-).
I browse shops that sell cheap reading glasses, then go through the various
models until I find ones that work well optically and but a number of that
model. Results vary very markedly - some are very good. Others are almost
worse than not being used. Presently I'm using 2.75 dioptre - both 2.5 and
3 dioptre are less-good for me.

The limits of the HD+ screen are easily noticed on SOME photos.

Below is a link to a 24 Mp, 4000 x 6000 head and shoulders "portrait" 16 MB
download.

I chose it (solely) for large file size for a JPG (so wide range of detail
changes) and the very fine hair on the man's forehead.
[FWIW this is ~= a rowing coach - I'd just been photographing his students
as they carried racing shells from a river and approached him to swap
contact details. This photo was as an 'aide memoir' for me. It works.][Note
the label on the side zip - that's a life-jacket!]

http://bit.ly/Sample_RowingCoach

There are lots of things that show screen resolution here but his ucrly
forehead hair, his eyelashes and to a lesser extent his along-the-top
hairline have (or should have) lots of detail.

This as produced by an in-camera RAW to JPG engine so is less than optimum.
DxO rate this lens about 6 Mp? equivalent by their standards AND it's at
about max aperture so softer than at best settings. And the screen is still
a limiting factor.

Use a 15 Mp rated lens (only one that I own achieves this*), run it at
optimum aperture, point it at eg a bride with white veil, and wish you had
a 4K monitor.
*Sony nee Minolta 50mm f/1.8. prime
But about NO lens available - not even the very very best - gets over about
20 Mp DxO rating.

Russell

John Guillory

2014-05-17 07:00:27 UTC

I don't use dslr, just a slr. Quality is unbeatable .... Something about true film that digital can't touch...

--
KF5QEO
John Guillory
***@yahoo.com
Cell: 601-754-9233
Pinger: 337-240-7890
Google Voice: 601-265-1307

Post by RussellMc
(2) > ... someone said the reason Apple has such a pathetic camera is
because the human eye isn't capable of perceiving anything better ...
Would this be the Apple that produces the "Retina" displays aimed at
exceeding perceivable dot pitch at typical viewing distances so that the
eye is well served?
Apple's cameras are OK enough with lots of light. They are not as good as
those in good dedicated cameras because Apple think they can get away with
spending less than that would take. They can use tiny sensors, add lots of
megapixels and the Apple experience and most people's wants are met. 'Most
people' is usually enough. Large sensors require large optics and cost
rises rapidly.
Many of the photos that I take with a DSLR are blurred and/or exposed badly
and/or framed badly and/or ... .
If I used a phone camera most of these ones would not exist at all.
Especially when I travel, the camera is an extension to my arm and, as well
as record of travel, and purposeful quality-directed photos, I also push
the camera beyond its abilities, and then see what I have managed to do
well enough to be worthwhile. Surprised the person who pulls a strange face
or adopts a ridiculous pose for a brief moment in front of my camera as a
challenge to the cameraman. Most are quite amused when shown the photo(s)
that quite often manage to get taken in such moments of levity. 'Good
quality' well-lit well focused photos are always 'nice to have', but SOME
of the best photos manage only some or even none of these.
A top DSLR seems to take photos almost before the shutter button is pressed
- so much so that in unsighted photos from moving vehicles you need to
trail the spot where your brain says the subject is.) A cameraphone or even
OK point & shoots are far too unresponsive for this. [I use them too, but
differently].
___________
(1)
Just curious, but what is the dot pitch of your eyes, and are they factory

My son's comments on getting a 4k monitor included - "This looks to have
more detail than reality - I'm going to stay here inside where it's warm".
I have very normal 'failing with age' eyes.
I wear $2 shop reading glasses BUT carefully chosen to have a diopter
rating to suit screen and viewing distance that I usually use.
Glasses that I carry or wear around tend to have short lifetimes. Very
strange :-).
I browse shops that sell cheap reading glasses, then go through the various
models until I find ones that work well optically and but a number of that
model. Results vary very markedly - some are very good. Others are almost
worse than not being used. Presently I'm using 2.75 dioptre - both 2.5 and
3 dioptre are less-good for me.
The limits of the HD+ screen are easily noticed on SOME photos.
Below is a link to a 24 Mp, 4000 x 6000 head and shoulders "portrait" 16 MB
download.
I chose it (solely) for large file size for a JPG (so wide range of detail
changes) and the very fine hair on the man's forehead.
[FWIW this is ~= a rowing coach - I'd just been photographing his students
as they carried racing shells from a river and approached him to swap
contact details. This photo was as an 'aide memoir' for me. It works.][Note
the label on the side zip - that's a life-jacket!]
http://bit.ly/Sample_RowingCoach
There are lots of things that show screen resolution here but his ucrly
forehead hair, his eyelashes and to a lesser extent his along-the-top
hairline have (or should have) lots of detail.
This as produced by an in-camera RAW to JPG engine so is less than optimum.
DxO rate this lens about 6 Mp? equivalent by their standards AND it's at
about max aperture so softer than at best settings. And the screen is still
a limiting factor.
Use a 15 Mp rated lens (only one that I own achieves this*), run it at
optimum aperture, point it at eg a bride with white veil, and wish you had
a 4K monitor.
*Sony nee Minolta 50mm f/1.8. prime
But about NO lens available - not even the very very best - gets over about
20 Mp DxO rating.
Russell
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Nicola Perotto

2014-05-17 10:52:42 UTC

Post by RussellMc
Many of the photos that I take with a DSLR are blurred and/or exposed badly
and/or framed badly and/or ... .

Here some interesting thoughts:
https://nikoneurope-en.custhelp.com/app/answers/detail/a_id/55047/kw/movement

Eg one problem I had:

As pixel counts have increased, the size of a single pixel has decreased.
For example, if two DX-format cameras; the D40 (image size: 3008 x 2000) and
the D3200 (image size: 6016 x 4000) are compared, the pixel size of the
D3200 is approximately a quarter of that of the D40. When images are
displayed on a computer monitor at 100%, D3200 images are actually displayed
approximately 4 times larger than D40 images (area ratio). Even if images
are captured under the same conditions and with the same level of hand or
camera movement, blur in the D3200 images could effectively be quadrupled
when displayed and become more noticeable. For this reason, it can be said
that high pixel count cameras are more susceptible to slight movement.

Robert Dvoracek

2014-05-17 15:16:17 UTC

Post by RussellMc
Many of the photos that I take with a DSLR are blurred and/or exposed badly
and/or framed badly and/or ... .

https://nikoneurope-en.custhelp.com/app/answers/detail/a_id/55047/kw/movement
As pixel counts have increased, the size of a single pixel has decreased.
For example, if two DX-format cameras; the D40 (image size: 3008 x 2000) and
the D3200 (image size: 6016 x 4000) are compared, the pixel size of the
D3200 is approximately a quarter of that of the D40. When images are
displayed on a computer monitor at 100%, D3200 images are actually displayed
approximately 4 times larger than D40 images (area ratio). Even if images
are captured under the same conditions and with the same level of hand or
camera movement, blur in the D3200 images could effectively be quadrupled
when displayed and become more noticeable. For this reason, it can be said
that high pixel count cameras are more susceptible to slight movement.

This is so true. Photography has always been, and will probably continue to be for some time to come, a tradeoff between graininess, blur, and depth of field.

Richard R. Pope

2014-05-18 00:32:29 UTC

Hello all,
Video resolution is like the resolution of sound in many ways. The
average human can perceive sound frequencies between about 20Hz and
18KHz. There are people that can hear as low as 5 Hz and others that can
hear as high as 22KHz. These are usually women. Ever wonder way most
horizontal circuits run at 25 KHz. It is because almost no one can hear
a frequency that high. The standard frequency 75 years ago used to be
only 20 KHz. The designers couldn't hear this noise because they were
all men at the time. But they started receiving complaints from
customers that their wives were developing headaches when the first TVs
were operating. It was traced to the horizontal osc but it took a women
to figure it out.
There is reason for me going into this amount of detail because it
begs the question, if most people can only hear from 20 Hz to 18 KHz why
are high end stereos designed to recreate sound from as low as 1 or 2 Hz
up to 25 KHz. It is because of perception. If those frequencies are
missing the sound just doesn't feel as good. It lacks content. Worst is
a system that is able to recreate these frequencies but in the process
it distorts the lower and higher frequencies. This will drive even the
average listener nuts.
Well it is the same with video. The average person can only discern
about 200,000 colors and a resolution of about 480x480. Any more than
that would seem to be a waste of money. But wait, remember I said video
is similar to sound. The extra colors and higher resolution allows the
viewer to perceive a fuller and more dynamic picture even though if you
ran the proper tests you would find that the viewer can't perceive the
extra colors. I am blessed in that I can perceive about 300K colors. It
is kind of cool to see hues of colors that others don't see any
difference in.
So I can understand someone being able to tell the difference
between and HD display and a 4096x4096 EHD display. But most people
can't but it does look better. This is especially true as the display
gets larger and larger. If you double the display size you either have
to quadruple the number of pixels or you have to quadruple the size of
the pixels which makes the display grainier, especially up close.
Thanks,
rich!

Post by RussellMc
Many of the photos that I take with a DSLR are blurred and/or exposed badly
and/or framed badly and/or ... .

John Gardner

2014-05-18 00:54:22 UTC

... blessed in that I can perceive about 300K colors...

Blessed, or cursed - Depending... :)

--
Eppur, si muove...

Sean Breheny

2014-05-18 13:20:20 UTC

Hi Rich,

I thought that the horizontal sweep frequency for NTSC analog TV was
15.7kHz, not 25kHz. I just checked PAL and SECAM and they are very close to
15.7kHz as well.

Sean

Post by Richard R. Pope
Hello all,
Video resolution is like the resolution of sound in many ways. The
average human can perceive sound frequencies between about 20Hz and
18KHz. There are people that can hear as low as 5 Hz and others that can
hear as high as 22KHz. These are usually women. Ever wonder way most
horizontal circuits run at 25 KHz. It is because almost no one can hear
a frequency that high. The standard frequency 75 years ago used to be
only 20 KHz. The designers couldn't hear this noise because they were
all men at the time. But they started receiving complaints from
customers that their wives were developing headaches when the first TVs
were operating. It was traced to the horizontal osc but it took a women
to figure it out.
There is reason for me going into this amount of detail because it
begs the question, if most people can only hear from 20 Hz to 18 KHz why
are high end stereos designed to recreate sound from as low as 1 or 2 Hz
up to 25 KHz. It is because of perception. If those frequencies are
missing the sound just doesn't feel as good. It lacks content. Worst is
a system that is able to recreate these frequencies but in the process
it distorts the lower and higher frequencies. This will drive even the
average listener nuts.
Well it is the same with video. The average person can only discern
about 200,000 colors and a resolution of about 480x480. Any more than
that would seem to be a waste of money. But wait, remember I said video
is similar to sound. The extra colors and higher resolution allows the
viewer to perceive a fuller and more dynamic picture even though if you
ran the proper tests you would find that the viewer can't perceive the
extra colors. I am blessed in that I can perceive about 300K colors. It
is kind of cool to see hues of colors that others don't see any
difference in.
So I can understand someone being able to tell the difference
between and HD display and a 4096x4096 EHD display. But most people
can't but it does look better. This is especially true as the display
gets larger and larger. If you double the display size you either have
to quadruple the number of pixels or you have to quadruple the size of
the pixels which makes the display grainier, especially up close.
Thanks,
rich!

Post by RussellMc
Many of the photos that I take with a DSLR are blurred and/or exposed

badly

Post by RussellMc
and/or framed badly and/or ... .

https://nikoneurope-en.custhelp.com/app/answers/detail/a_id/55047/kw/movement

Post by Nicola Perotto
As pixel counts have increased, the size of a single pixel has

decreased.

Post by Nicola Perotto
For example, if two DX-format cameras; the D40 (image size: 3008 x

2000) and

Post by Nicola Perotto
the D3200 (image size: 6016 x 4000) are compared, the pixel size of

the

Post by Nicola Perotto
D3200 is approximately a quarter of that of the D40. When images are
displayed on a computer monitor at 100%, D3200 images are actually

displayed

Post by Nicola Perotto
approximately 4 times larger than D40 images (area ratio). Even if

images

Post by Nicola Perotto
are captured under the same conditions and with the same level of

hand or

Post by Nicola Perotto
camera movement, blur in the D3200 images could effectively be

quadrupled

Post by Nicola Perotto
when displayed and become more noticeable. For this reason, it can

be said

Post by Nicola Perotto
that high pixel count cameras are more susceptible to slight

movement.
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Rupert Swarbrick

2014-05-18 14:52:28 UTC

Post by Richard R. Pope
Video resolution is like the resolution of sound in many ways. The
average human can perceive sound frequencies between about 20Hz and
18KHz. There are people that can hear as low as 5 Hz and others that can
hear as high as 22KHz. These are usually women. Ever wonder way most
horizontal circuits run at 25 KHz. It is because almost no one can hear
a frequency that high. The standard frequency 75 years ago used to be
only 20 KHz. The designers couldn't hear this noise because they were
all men at the time. But they started receiving complaints from
customers that their wives were developing headaches when the first TVs
were operating. It was traced to the horizontal osc but it took a women
to figure it out.

That's a brilliant story - thanks!

Post by Richard R. Pope
There is reason for me going into this amount of detail because it
begs the question, if most people can only hear from 20 Hz to 18 KHz why
are high end stereos designed to recreate sound from as low as 1 or 2 Hz
up to 25 KHz. It is because of perception. If those frequencies are
missing the sound just doesn't feel as good. It lacks content. Worst is
a system that is able to recreate these frequencies but in the process
it distorts the lower and higher frequencies. This will drive even the
average listener nuts.

This is interesting. Some time ago, I read this article:

http://people.xiph.org/~xiphmont/demo/neil-young.html

which I remembered suggesting that's a bad idea. Looking again, it seems
I remembered correctly. Can you give any references for properly blinded
studies that support the "doesn't feel as good" claim?

Rupert

Peter Johansson

2014-05-18 18:45:56 UTC

Post by Rupert Swarbrick

http://people.xiph.org/~xiphmont/demo/neil-young.html
which I remembered suggesting that's a bad idea. Looking again, it seems
I remembered correctly. Can you give any references for properly blinded
studies that support the "doesn't feel as good" claim?

David C Brown

2014-05-18 21:09:44 UTC

I don't think that the comparison between sound and colour is at all valid.
Simultaneous sounds interact with each other in a way that colours don't
and there is no visual equivalent of the beat frequency.

Post by Peter Johansson

Post by Rupert Swarbrick

Frequency response is generally specified at 3 db down. A system with
greater frequency response is most likely going to have a flatter
response in the range of hearing.
At the lower end, you can feel frequencies below the range of hearing.
-p.
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Harold Hallikainen

2014-05-18 21:55:47 UTC

Post by David C Brown
I don't think that the comparison between sound and colour is at all valid.
Simultaneous sounds interact with each other in a way that colours don't
and there is no visual equivalent of the beat frequency.

Both sound and light add linearly, so there is not heterodyne between them
in our usual environment. For sound, if we have two frequencies of 900Hz
and 1.1kHz, the individual signals remain separate, but this is also the
same waveform that would be generated by modulating a 1kHz tone with 100Hz
using double sideband suppressed carrier amplitude modulation. The
envelope of a DSPSC signal is the same as would appear if we were to full
wave rectify the modulating frequency, which creates a doubling of the
modulating frequency (along with some other components). We don't know if
they are individual tones or a single tone with tremolo.

With color, our eyes have three bandpass filters (X, Y, and Z) similar to
RGB except that the X filter is similar to red but has a second peak in
the blue region.

We detect monochromatic colors by "slope detecting" between the filters.
Yellow hits both the X and Y filters. This yellow can be either
monochromatic yellow or any other spectrum that causes the same output of
these filters (such as monochromatic light at the X peak and Y peak).

Detection of violet is interesting. As we move to shorter wavelengths
above blue, the output of the Z filter starts going up, but the X filter
(similar to red) starts going up. We determine this is violet. We can
simulate violet by driving the X and Z filters with red and blue light.

It's interesting that we have these three filters and the shapes of the
filters. It seems that we'd be able to do good color perception with just
two filters, and I think some animals have two. I guess the three filters
gives us better color perception.

Harold

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William "Chops" Westfield

2014-05-21 08:24:22 UTC

Post by RussellMc
entry-level 4K capable video cards

BTW, I'm extremely curious as to how well 4K monitors render the max resolutions available from older video cards (say 2560x1440)

Thanks
Bill W

RussellMc

2014-05-17 11:41:04 UTC

Post by RussellMc
Many of the photos that I take with a DSLR are blurred and/or exposed

badly

Post by RussellMc
and/or framed badly and/or ... .

I did not make what I intended to say clear enough for all.
Many of my photos are more or less well focused, well exposed and passably
well framed. And some extremely well so in all 3 respects. And the
proportion varies with circumstance.

If I wished to I could go out wandering for a day in a foreign land and at
the end of the day have almost all photos reasonably good technically.
That, however, is "not me". Or not entirely. As well as the nicely framed
photos of the Taj Mahal, (near) perfect reflection in the long mirror pond,
symmetrically arranged and with as few (other) tourists in frame as I can
reasonably manage, there will also, from the same site, be the squirrel at
moment of leaping off the pathway, the Eagle that I suddenly see just about
to enter a zone where a glorious photo MIGHT be possible, the young woman
looking at her cellphone (text presumably) - mouth like an O in a split
split second of surprise, monkey leaping away from the boy who took the
fight to the monkey before it got in first, sol dier in full regalia,
automatic at the ready steely eye.... [no, of course I wouldn't take that,
surely], ... . The Taj will be reasonably well done. The rest may be, or
noyt, depending how fast/ready/balanced/surreptitious/ ... I was as the
fleeting moment passed. Amongst these are the blurred, badly exposed, badly
framed - and often enough the most brilliant of the days take.
Reality was: [Squirrel - some good ones, Eagles - some good, largely too
far away, Mouth like an O - not quite sharp but classic, Monkey & boy -
blurred , alas, Sol ... who me? very nice.]
Just checked - mind faileth - Mouth like an O was in China, not at Taj. And
not texting. -> http://bit.ly/Photo_JonathanJo (I just noticed the
ear-ring for the first tiem :-) ).
With luck you may get chained spurs of the moment :-)
http://bit.ly/Photos_Mummymummy

Post by Nicola Perotto
https://nikoneurope-en.custhelp.com/app/answers/detail/a_id/55047/kw/movement

Some good advice.

Re >

Post by Nicola Perotto
Even if images are captured under the same conditions and with the same
level of hand or
camera movement, blur in the D3200 images could effectively be
quadrupled
when displayed
...

Some merit in that. But shake or motion is liable to be linear rather than
areal in effect so a factor of more like 2 is arguably more appropriate.
My experience is that the "old rule" applies - hand held sharpness can be
achieved with care with shutter speeds aas as long as 1/focal_length_in_mm
s.
eg 50mm _. >= 1/50s. 250mm -> 1/250s.
Experience, Ninja breathing, luck ... can allow you to get 2 to 4 times
slower often. Lens or body stabilisation also can give you 2 to 3 stops of
shake reduction (but not target movement motion reduction).
Panning helps muchly - experience, skill, luck apply.

Russell

RussellMc

2014-05-17 13:51:12 UTC

I see Facebook is playing games with links again and directing references
to the top of an album rather than the photo intended.

I'll find a better way of doing this but for now, if you've clicked a link
from this thread and get a picture of a 3 headed alien and "Area 51. Aliens
in this land" text (as one does) then press left cursor arrow to step back
through album from end.

One back is the "chained spurs of the moment (small girl + photographer)
Two back is 'Mouth like an O" ("Jonathan Jo...")

Russell

Post by RussellMc
Many of the photos that I take with a DSLR are blurred and/or exposed

badly

Post by RussellMc
and/or framed badly and/or ... .

I did not make what I intended to say clear enough for all.
Many of my photos are more or less well focused, well exposed and passably
well framed. And some extremely well so in all 3 respects. And the
proportion varies with circumstance.
If I wished to I could go out wandering for a day in a foreign land and at
the end of the day have almost all photos reasonably good technically.
That, however, is "not me". Or not entirely. As well as the nicely framed
photos of the Taj Mahal, (near) perfect reflection in the long mirror pond,
symmetrically arranged and with as few (other) tourists in frame as I can
reasonably manage, there will also, from the same site, be the squirrel at
moment of leaping off the pathway, the Eagle that I suddenly see just about
to enter a zone where a glorious photo MIGHT be possible, the young woman
looking at her cellphone (text presumably) - mouth like an O in a split
split second of surprise, monkey leaping away from the boy who took the
fight to the monkey before it got in first, sol dier in full regalia,
automatic at the ready steely eye.... [no, of course I wouldn't take that,
surely], ... . The Taj will be reasonably well done. The rest may be, or
noyt, depending how fast/ready/balanced/surreptitious/ ... I was as the
fleeting moment passed. Amongst these are the blurred, badly exposed, badly
framed - and often enough the most brilliant of the days take.
Reality was: [Squirrel - some good ones, Eagles - some good, largely too
far away, Mouth like an O - not quite sharp but classic, Monkey & boy -
blurred , alas, Sol ... who me? very nice.]
Just checked - mind faileth - Mouth like an O was in China, not at Taj.
And not texting. -> http://bit.ly/Photo_JonathanJo (I just noticed the
ear-ring for the first tiem :-) ).
With luck you may get chained spurs of the moment :-)
http://bit.ly/Photos_Mummymummy

Post by Nicola Perotto
https://nikoneurope-en.custhelp.com/app/answers/detail/a_id/55047/kw/movement

Some good advice.
Re >

cdb

2014-05-23 20:47:39 UTC

Lenovo have just released a nice looking 4K 28" LCD monitor. Has a KVM
included - AU$799 inc GST.
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veegee

2014-05-24 01:00:37 UTC

AMD R9 280 is very good. It'll last you at least 4 or 5 years. At least. My
AMD 6950 lasted me 4 years and still running strong.

Post by RussellMc
Sought: Comments & recommendations on acceptable performance low-cost
entry-level 4K capable video cards for "desktop" applications.

RussellMc

2017-11-24 11:04:02 UTC