Chip with simple program for Toy

[default]

On Sun, 12 Aug 2018 00:54:04 +0800, "Mr. Man-wai Chang"
<toylet.toylet@gmail.com> wrote:

On 8/12/2018 12:50 AM, nospam wrote:
In article <pkn432$pvc$1@toylet.eternal-september.org>, Mr. Man-wai
Chang <toylet.toylet@gmail.com> wrote:


But how do you get a 100% TRUE lossless original? Using good, old
film-based cameras?

film is more lossy than digital.


I don't know much about photography films. And you might need to talk
about the size (length x width) as well as the resolution of the senors
and films!

But isn't film molecular level?

You'd have to compare the format size of film. 70 mm film is probably
better than most digital cameras can resolve. (excluding some
spacecraft of course)

The slower the film the better the resolution - or that's the way it
worked when I was into the hobby.

 

[John Larkin]

On Sun, 12 Aug 2018 00:54:04 +0800, "Mr. Man-wai Chang"
<toylet.toylet@gmail.com> wrote:

On 8/12/2018 12:50 AM, nospam wrote:
In article <pkn432$pvc$1@toylet.eternal-september.org>, Mr. Man-wai
Chang <toylet.toylet@gmail.com> wrote:


But how do you get a 100% TRUE lossless original? Using good, old
film-based cameras?

film is more lossy than digital.


I don't know much about photography films. And you might need to talk
about the size (length x width) as well as the resolution of the senors
and films!

But isn't film molecular level?

Film is quantized to grain size.



--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Mr. Man-wai Chang]

On 8/12/2018 1:19 AM, nospam wrote:

Should we always compare 135
film against CMOS sensors of different size?

always the same size format. otherwise it's not a valid comparison.

In reality, we just need to do the job right and fair, not about
comparison or superiority!

What if... a big what if.... all CMOS on Earth were fried by solar
storm? Maybe that explained why a man is up there in ISS.

--
@~@ Remain silent! Drink, Blink, Stretch! Live long and prosper!!
/ v \ Simplicity is Beauty!
/( _ )\ May the Force and farces be with you!
^ ^ (x86_64 Ubuntu 9.10) Linux 2.6.39.3
不借貸! 不詐騙! 不賭錢! 不援交! 不打交! 不打劫! 不自殺! 不求神! 請考慮綜援
(CSSA):
http://www.swd.gov.hk/tc/index/site_pubsvc/page_socsecu/sub_addressesa

 

[nospam]

In article <pko8ri$sc$1@toylet.eternal-september.org>, Mr. Man-wai
Chang <toylet.toylet@gmail.com> wrote:

Should we always compare 135
film against CMOS sensors of different size?

always the same size format. otherwise it's not a valid comparison.

In reality, we just need to do the job right and fair, not about
comparison or superiority!

you're the one making comparisons.

What if... a big what if.... all CMOS on Earth were fried by solar
storm? Maybe that explained why a man is up there in ISS.

what if you stopped posting rubbish?

 

[Mr. Man-wai Chang]

On 8/12/2018 11:22 AM, nospam wrote:

In reality, we just need to do the job right and fair, not about
comparison or superiority!

you're the one making comparisons.

What if... a big what if.... all CMOS on Earth were fried by solar
storm? Maybe that explained why a man is up there in ISS.

what if you stopped posting rubbish?

Well, calm down... professor!? Let's continue later.

--
@~@ Remain silent! Drink, Blink, Stretch! Live long and prosper!!
/ v \ Simplicity is Beauty!
/( _ )\ May the Force and farces be with you!
^ ^ (x86_64 Ubuntu 9.10) Linux 2.6.39.3
不借貸! 不詐騙! 不賭錢! 不援交! 不打交! 不打劫! 不自殺! 不求神! 請考慮綜援
(CSSA):
http://www.swd.gov.hk/tc/index/site_pubsvc/page_socsecu/sub_addressesa

 

[whit3rd]

On Saturday, August 11, 2018 at 10:19:37 AM UTC-7, nospam wrote:

size doesn't change anything. film is very lossy and much less accurate
than digital.

That's complete nonsense. Film, first, has a few-photons threshold, and
the color film variants have some filter layers (so there is light absorbed other
than by the developable grains). Solid-state sensors have a few photons/sec
background noise, and to get color, you mask with filters a trio of sensors
(each insensitive to colors outside the designed range).

Grain size limits the film resolution, pixel size limits the digital image resolution.

Either technology can match what a human eye sees. Neither is
perfect in any respect, though a digital image can be stored with checksums and
presumably age won't change it. If age DID change one bit of one pixel, though, it'd invalidate
the checksum- some disk drives will refuse to even give you a guess as to what
was stored, when the checksum says it's bad.

 

[Mr. Man-wai Chang]

On 8/12/2018 5:18 PM, Mr. Man-wai Chang wrote:

On 8/12/2018 5:14 PM, Steve Hough wrote:
nospam was thinking very hard :

what if you stopped posting rubbish?

Why not stop feeding the troll?

Switching topic to mental state...

If you don't wanna continue to answer, just say so. You can also throw
me to Google Search.

I wanna remind you that this is not your company, definitely not a court
room. This is just a causal chat. Your honor and income will not be
affected.

Do you always do that when you were still in schools? Oh well... amazed
me. Maybe I am too lucky not studying in your schools.

--
@~@ Remain silent! Drink, Blink, Stretch! Live long and prosper!!
/ v \ Simplicity is Beauty!
/( _ )\ May the Force and farces be with you!
^ ^ (x86_64 Ubuntu 9.10) Linux 2.6.39.3
不借貸! 不詐騙! 不賭錢! 不援交! 不打交! 不打劫! 不自殺! 不求神! 請考慮綜援
(CSSA):
http://www.swd.gov.hk/tc/index/site_pubsvc/page_socsecu/sub_addressesa

 

[Tim]

"Mr. Man-wai Chang" <toylet.toylet@gmail.com> wrote in newskn96p$qar$1
@toylet.eternal-september.org:

On 8/12/2018 2:08 AM, nospam wrote:
In article <pkn8cs$lqs$1@toylet.eternal-september.org>, Mr. Man-wai
Chang <toylet.toylet@gmail.com> wrote:


But how do you determine how close a digital image get to the
original
without a reference? You have to have a control as in experiment!

the reference is the original


In a court trial, how do you do that? You cannot take the physical
reality into a court... there is also the time factor. Whatever
happened
in reality might not repeat itself before the court.

Example scenerio:

I'm out with my trusty movie/video camera, and happen to capture a driver
running a red light/stop sign and striking your car. I only discover this
when I receive the file back from developing/watch the video. Being the
good citizen that I am, I contact the police and tell them about the
evidence I have. `They come and take said evidence/or make a copy of said
evidence. I sign a sworn statement concerning how I optained the
original. The evidence is placed into a sealed bag/container, and I sign
as the originator/owner, and the person receiving the evidence signs as
the one receiving it from me. They then sign it into the evidence storage
at their office. Anyone making a copy or otherwise having that evidence
in their possession outside of the evidence storage area has to sign for
the original and why they had access/possession of it. This process
continues until the evidence is used in court, if it is. Along with the
evidence comes the 'chain of evidence possession' documenting its origin
and any and all accesses to it up to the time it is presented as evidence
in court. This is the accepted means of documenting how the evidence was
created and accessed the veracity and and protection of the evidence all
along the process. If there is a question of the accuracy of any copies
made the 'chain of possession' documentation and expert testimony is used
to resolve it.

Any analog process of duplication incurrs some loss.
A digital proccess of dublication of a digital original can occur without
loss, depending on the specifics of the process used to create the
'duplicate'.

 

[knuttle]

On 8/11/2018 11:17 PM, Mr. Man-wai Chang wrote:

On 8/12/2018 1:19 AM, nospam wrote:

Should we always compare 135
film against CMOS sensors of different size?

always the same size format. otherwise it's not a valid comparison.


In reality, we just need to do the job right and fair, not about
comparison or superiority!

What if... a big what if.... all CMOS on Earth were fried by solar
storm? Maybe that explained why a man is up there in ISS.

This is sort of an answer to the original question.

quote: "The resolution of film images depends upon the area of film used
to record the image (35 mm, medium format or large format) and the film
speed. Estimates of a photograph's resolution taken with a 35 mm film
camera vary. More information may be recorded if a fine-grain film is
used, while the use of poor-quality optics or coarse-grained film may
yield lower image resolution. A 36 mm × 24 mm frame of ISO 100-speed
film was initially estimated to contain the equivalent of 20 million
pixels,[6] or approximately 23,000 pixels per square mm. "


In my experience, my 12 mega pixel Olympus camera gives me pictures as
good as my Old Miranda Camera with a good slide film.


With a chemical camera the resolution is limited to the grain size in a
film. However with a print the quality of the paper the images is
printed on will also affect the resolution in the print

With a digital in my opinion has a large range of light conditions under
which you can get good images.

With all of the above, in both types of camera it is the lens system.
Poor quality lens gives poor quality images regardless of the film or
CMOS. As an example I have a cheap phone with a 1.3 megapixel camera.
It gives me consistently better pictures than my tablet which has a 2
megapixel CMOS. This is evident in that with the phone I can easily get
readable images of printed pages, but impossible with the tablet.

In other words with lens systems you can not make a silk purse out of of
a sow's ear, no matter how you process.

 

[NY]

"knuttle" <keith_nuttle@sbcglobal.net> wrote in message
newskp90o$kbm$1@dont-email.me...

With a chemical camera the resolution is limited to the grain size in a
film. However with a print the quality of the paper the images is printed
on will also affect the resolution in the print

With a digital in my opinion has a large range of light conditions under
which you can get good images.

With all of the above, in both types of camera it is the lens system. Poor
quality lens gives poor quality images regardless of the film or CMOS. As
an example I have a cheap phone with a 1.3 megapixel camera. It gives me
consistently better pictures than my tablet which has a 2 megapixel CMOS.
This is evident in that with the phone I can easily get readable images of
printed pages, but impossible with the tablet.

The other thing with digital is that the quality of the image is affected by
the post-processing and the amount of noise that the sensor generates. Noise
increases with increased amplification (higher ISO setting) and with reduced
pixel size: a phone with a small sensor (so each pixel is smaller) will
produce more noise than an SLR with a larger sensor with the same
resolution.

Often this is masked by post-processing which manifests itself as localised
blurring of detail.

My SLR at 3200 ASA produces a less noisy picture than my phone camera at a
much lower ISO setting. The SLR's lens is also better, but that's a separate
issue. One other factor is that phone cameras are often a fixed focal
length, so if you zoom in you are using a progressively smaller area of the
sensor which increases noise and (even more so) decreases resolution - just
like making a print from a progressively smaller part of the negative.

Digital also has the advantage that it is much easier to correct for
different colours of light (sunlight / cloud / daylight fluorescent / warm
white fluorescent / LED / tungsten), either manually with presets or
automatically. And the sensitivity of the sensor doesn't change at very
short or very long exposures: with film you had to make corrections both for
exposure and colour cast due to "reciprocity failure" whereby the normal
rule of "reduce shutter speed by one stop requires opening up aperture by
one stop" no longer applies. With negative film it wasn't too much of an
issue because neg film can produce a usable print from a negative with more
under or over exposure, and colour cast can be corrected at printing,
whereas slide film has much less exposure latitude and has no opportunity
for correcting colour cast, apart from by copying onto a new slide with a
filter in place, or by scanning to digital.

I was surprised at how much correction scanning does allow. I took some
night-time photos of an illuminated building and grossly overexposed (I was
guessing). The slides are very pale. When I scanned them (about 30 years
later!), I could correct for this increasing the contrast so the darkest
pale tones became nearly black and the lightest, almost clear film, became
white. Given that exposure at night is very subjective anyway (there is no
one "correct" exposure) this was good enough to produce better copies than
the original. If I'd been shooting on digital, I'd have seen the results of
my guesses immediately and corrected accordingly, either by looking at the
result or looking at the histogram (proportion of pixels with each
brightness - should look *very roughly* like a symmetrical bell-shaped
curve, assuming a typical scene, which night pictures often aren't because
of bright lights or shadows which are outside the range of what you want to
reproduce well (ie it's much more acceptable have some parts which are
totally black or bleached maxed-out white).

 

[nospam]

In article <adCdnTvNe-OnpO3GnZ2dnUU78bvNnZ2d@brightview.co.uk>, NY
<me@privacy.net> wrote:

The other thing with digital is that the quality of the image is affected by
the post-processing and the amount of noise that the sensor generates.

film is also affected by the processing and also the type of film.

Noise
increases with increased amplification (higher ISO setting) and with reduced
pixel size: a phone with a small sensor (so each pixel is smaller) will
produce more noise than an SLR with a larger sensor with the same
resolution.

film is similar. high iso films have more grain, while smaller formats
need to be enlarged more for the same size print.

 

[Phil Hobbs]

On 08/11/2018 01:15 PM, Mr. Man-wai Chang wrote:

On 8/12/2018 1:10 AM, nospam wrote:

I don't know much about photography films.

clearly.

And you might need to talk
about the size (length x width) as well as the resolution of the senors
and films!

yep.

But isn't film molecular level?

everything is.

Is your claim based on traditional size of film, which is 135?

But why can't we use a bigger film then? Should we always compare 135
film against CMOS sensors of different size?

A bit of possibly useful discussion:

https://electrooptical.net/News/photographic-film/

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
https://hobbs-eo.com

 

[NY]

"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> wrote in message
news:rY-dnfnTVJOFeuzGnZ2dnUU7-KGdnZ2d@supernews.com...

But why can't we use a bigger film then? Should we always compare 135
film against CMOS sensors of different size?


A bit of possibly useful discussion:

https://electrooptical.net/News/photographic-film/

One other factor to bear in mind: the depth of field varies with lens focal
length, not field of view of the subject. This means that if you take a
photo on 120 film and on 35 mm, with appropriate focal lengths of the two
lenses to give the same field of view of the subject in both cases, and use
the same aperture, the DOF will be less on the 120 photo than the 35 mm
photo. So if 80 mm gives a certain field of view on 120 and 50 mm gives the
same field of view (ie shows the same extent of the subject) on 50 mm, and
both lenses are at f 4 (and so both will use the same shutter speed for the
same speed of film), the 120 photo will have a shallower DOF. That is why it
is so difficult to get shallow DOF on a compact or phone camera, because the
lens is such a short focal length to suit the very small sensor, that almost
everything is in focus even at a wide aperture (and the lens might have more
artifacts and aberrations than the comparable lens that gives the same field
of view for a 35 mm camera). In all this, I'm talking about the field of
view of the *subject* - ie how much of the subject (wide/telephoto) is
included within the frame of film or the sensor.

This is why some drama TV programmes are shot on 16 mm or with a similar
size CMOS sensor, but with a 35 mm-format movie camera lens and an
intermediate ground-glass screen. This allows a shallower DOF to be achieved
for artistic reasons without having to open up the (16 mm format) lens to a
wider aperture which might show more lens flaws. The lens for 35 mm format
produces an image on the ground-glass screen that has a certain field of
view and depth of field which would be recorded on 35 mm film. The 16 mm
camera focuses that image (which is all at one plane) onto 16 mm film.

I wish I could find a URL that describes it, but I'm obviously not feeding
Google with the correct search keywords - a common problem I have.

 

[nospam]

In article <9LKdncSlBe9dVu_GnZ2dnUU78a_NnZ2d@brightview.co.uk>, NY
<me@privacy.net> wrote:

One other factor to bear in mind: the depth of field varies with lens focal
length, not field of view of the subject.

actually, it's aperture.

This means that if you take a
photo on 120 film and on 35 mm, with appropriate focal lengths of the two
lenses to give the same field of view of the subject in both cases, and use
the same aperture, the DOF will be less on the 120 photo than the 35 mm
photo.

nope. it will be identical for the same image quality.

So if 80 mm gives a certain field of view on 120 and 50 mm gives the
same field of view (ie shows the same extent of the subject) on 50 mm, and
both lenses are at f 4 (and so both will use the same shutter speed for the
same speed of film), the 120 photo will have a shallower DOF. That is why it
is so difficult to get shallow DOF on a compact or phone camera, because the
lens is such a short focal length to suit the very small sensor, that almost
everything is in focus even at a wide aperture (and the lens might have more
artifacts and aberrations than the comparable lens that gives the same field
of view for a 35 mm camera).

only because the lens on the cellphone can't open wide enough to match
the depth of field of the larger sensor camera.

however, the lens on larger sensor camera will likely be able stop down
to match the depth of field of the cellphone camera. some lenses might
not, but that's a physical lens limitation.

 

[Eric Stevens]

On Sun, 12 Aug 2018 00:54:04 +0800, "Mr. Man-wai Chang"
<toylet.toylet@gmail.com> wrote:

On 8/12/2018 12:50 AM, nospam wrote:
In article <pkn432$pvc$1@toylet.eternal-september.org>, Mr. Man-wai
Chang <toylet.toylet@gmail.com> wrote:


But how do you get a 100% TRUE lossless original? Using good, old
film-based cameras?

film is more lossy than digital.


I don't know much about photography films. And you might need to talk
about the size (length x width) as well as the resolution of the senors
and films!

But isn't film molecular level?

Not really. A film image is constructed of crystaline grains which are
far above molecules in size.
--

Regards,

Eric Stevens

 

[NY]

"nospam" <nospam@nospam.invalid> wrote in message
news:140820181208050337%nospam@nospam.invalid...

This means that if you take a
photo on 120 film and on 35 mm, with appropriate focal lengths of the two
lenses to give the same field of view of the subject in both cases, and
use
the same aperture, the DOF will be less on the 120 photo than the 35 mm
photo.

nope. it will be identical for the same image quality.

So as long as film grain isn't the limiting issue, you should be able to
take a photo on 120 film with a lens that gives a certain field of view, and
then on 35 mm with a different lens that gives the same field of view, and
if you use the same aperture on both lenses, you shouldn't see a shallower
DOF on a print from the larger format negative?

That goes against everything I've ever learned about photography, and the
fringe benefit of using larger film (the main one being finer level of
detail for the same type of film).

I'll have to try taking comparison photos on my SLR and compact cameras, to
test it.

As I thought, the SLR photo has a shallower DOF than the compact, for same
aperture and comparable lens focal lengths to give same field of view in
both photos.

Nikon D90, 18-200 mm lens, set to 150 mm, 35 mm equivalent=225mm, f5.6,
image size 4288 x 2848 pixels

https://s22.postimg.cc/phiylnsnl/DSC_0151.jpg


Canon Powershot SX260HS, 4.5-90 mm lens, set to 34 mm, no 35 mm equivalent
stated, f5.6, image size 4000 x 2664

https://s22.postimg.cc/k6420pe81/IMG_1316.jpg

Both these are full frame, both focussed on the pins of the mains adaptor in
the centre of the picture. Both pictures taken from same position (ie same
distance to subject in foreground). Very similar image resolution.

 

[nospam]

In article <kLadnZwoW7Yyf-7GnZ2dnUU78QfNnZ2d@brightview.co.uk>, NY
<me@privacy.net> wrote:

This means that if you take a
photo on 120 film and on 35 mm, with appropriate focal lengths of the two
lenses to give the same field of view of the subject in both cases, and
use
the same aperture, the DOF will be less on the 120 photo than the 35 mm
photo.

nope. it will be identical for the same image quality.

So as long as film grain isn't the limiting issue, you should be able to
take a photo on 120 film with a lens that gives a certain field of view, and
then on 35 mm with a different lens that gives the same field of view, and
if you use the same aperture on both lenses, you shouldn't see a shallower
DOF on a print from the larger format negative?

if you do that, then the image quality will be different, which means
other characteristics may also be different.

also, depth of field is a function of the physical aperture (not
f/stop), so if you use the same f/stop on both (for exposure purposes)
you're actually using a larger aperture on the longer focal length
lens, thus the difference you're seeing (along with the difference in
image quality from the larger format, which can't be ignored).

> That goes against everything I've ever learned about photography,

it's a common myth.

and the
fringe benefit of using larger film (the main one being finer level of
detail for the same type of film).

in other words, different image quality.

this explains it exceptionally well:
<http://www.clarkvision.com/articles/dof_myth/>
A commonly cited advantage of smaller digital cameras is their
greater depth-of-field. This is incorrect.

€ The myth, simply stated, is: smaller digital cameras have a larger
depth-of-field than larger digital cameras.

The simple reason why the myth is incorrect is that depth of field is
set by aperture, focal length, and a criterion for spatial
resolution, and if one keeps aperture of the larger camera the same
as that in the smaller camera, the two cameras record the same image
with the same signal-to-noise ratio and the same depth of field with
the same exposure time. Below are details explaining why this is
true, and Figure 1 gives an example.
....
Given the identical photon noise, exposure time, enlargement size,
and number of pixels giving the same spatial resolution (i.e. the
same total image quality), digital cameras with different sized
sensors will produce images with identical depths-of-field. (This
assumes similar relative performance in the camera's electronics,
blur filters, and lenses.) The larger format camera will use a higher
f/ratio and an ISO equal to the ratio of the sensor sizes to achieve
that equality. If the scene is static enough that a longer exposure
time can be used, then the larger format camera will produce the same
depth-of-field images as the smaller format camera, but will collect
more photons and produce higher signal-to-noise images. Another way
to look at the problem, is the larger format camera could use an even
smaller aperture and a longer exposure to achieve a similar
signal-to-noise ratio image with greater depth of field than a
smaller format camera. Thus, the larger format camera has the
advantage for producing equal or better images with equal or better
depth-of-field as smaller format cameras.

 

[NY]

"nospam" <nospam@nospam.invalid> wrote in message
news:150820181016378795%nospam@nospam.invalid...

That goes against everything I've ever learned about photography,

it's a common myth.

and the
fringe benefit of using larger film (the main one being finer level of
detail for the same type of film).

in other words, different image quality.

I hadn't appreciated that image quality affected DOF. So same lens, same
camera, same aperture (but different shutter speed) on very slow
fine-grained film and very fast coarse-grained film will produce different
DOF?

Well, well.

this explains it exceptionally well:
http://www.clarkvision.com/articles/dof_myth/
A commonly cited advantage of smaller digital cameras is their
greater depth-of-field. This is incorrect.

Interesting article. The reason for the myth is that we are comparing the
wrong things and keeping the wrong things constant in the comparison. The
longer lens needed to produce the same field of view on the camera with the
larger sensor needs to be stopped down further make the *absolute* aperture
the same as for the camera with a smaller sensor and correspondingly smaller
focal length to give same field of view. Comparing f5.6 on the longer lens
with f5.6 on the shorter lens is wrong in terms of DOF. Understood!

Of course, in practical photographic terms, we tends to constraint aperture
to *roughly* the same range of f numbers for any lens. A lens that is 10x as
long doesn't have apertures which are roughly 1/10 (in f number terms) - on
all lenses, they will always be around f2 - f16 give or take a couple of f
numbers either way. That's so the light-gathering abilities of the lenses
are comparable.

So a camera with a small sensor will have a lens that has usable apertures
in terms of light-gathering capabilities which equate to a camera with a
larger sensor and hence a longer lens that has much smaller apertures and
therefore needs much longer exposures if film speed / CMOS sensitivity is
the same.


So a smaller camera doesn't inherently produce a greater depth of field, but
when it used in the same conditions of image brightness and film speed, and
the need to avoid diffraction due to excessively small apertures, the
smaller camera's range of *available* apertures produce a greater DOF than
the *available* range of apertures on a longer lens on a larger camera.

In other words, it's the age-old difference between theory and practical
usability.

 

[NY]

"NY" <me@privacy.net> wrote in message
news:SbOdnTGdYutB0unGnZ2dnUU78cHNnZ2d@brightview.co.uk...

Interesting article. The reason for the myth is that we are comparing the
wrong things and keeping the wrong things constant in the comparison. The
longer lens needed to produce the same field of view on the camera with
the larger sensor needs to be stopped down further make the *absolute*
aperture the same as for the camera with a smaller sensor and
correspondingly smaller focal length to give same field of view. Comparing
f5.6 on the longer lens with f5.6 on the shorter lens is wrong in terms of
DOF. Understood!

The only thing that I'll need to read a few more times is the issue of
number of photons. I can see that this affects how much light the
film/sensor receives and therefore the brightness of the image. But I can't
see how it has any effect on the DOF of that image which is a purely
optical, lens issue: a dim image and a bright image will still have the same
objects in sharp focus and the same objects blurred by some amount.

So if in some way you halve the number of photos reaching the sensor (by
making the aperture smaller, by using a neutral density or by dimming the
illumination of the subject) then as long as you make the sensor twice as
sensitive or double the exposure time then the recorded image will be the
same. Of these, only altering the aperture alters the DOF. As long as the
aperture doesn't change, you can change all the other parameters and as long
as you do so proportionally, the image will be identical, both in brightness
and in DOF.

To think of it another way, suppose you have two sensors which have pixels
which are same size. In one case, the pixels border each other, without any
space between them; in the other case the pixels are the same size but
spaced more widely.

Sensor 1
x x x
x x x
x x x

versus

Sensor 2
x x x

x x x

x x x

The pixel size (the x) is the same size. So the size of the buckets is the
same.

But if the pixels are spaced more widely, the sensor will be physically
larger and will need a longer lens to capture the same field of view (and so
will need a smaller f number to give the same absolute size of aperture and
hence DOF).

But if we replace Sensor 2 by the more normal situation where the pixels are
bigger although their spacing hasn't altered (Sensor 3), the same lens is
needed and for the same aperture the DOF will be the same. I presume...

Sensor 3

X X X

X X X

X X X

The spacing is the same but the pixel size has increased from x to X which
means the larger buckets can gather more pixels.


I'm still struggling to see how altering the "size of the buckets" has
affected the DOF, if the pitch of the buckets is the same.


My brain hurts. I'm probably over-thinking all this

 

[Mr. Man-wai Chang]

On 8/24/2018 2:14 AM, BurfordTJustice wrote:

You do not control your home..the government does, just like children

Europe to ban halogen lightbulbs

After nearly 60 years of lighting homes halogens will be replaced with more
energy efficient LEDs
...

Is LED production more polluting than traditional light bulbs?

Any dirty secrets behind LED technology and pollution?

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