8Mp Digital The Theoretical 35mm Quality Equivelant

Harvey posted:

"Petros" wrote in message
...
Skip M posted:
"Crownfield" wrote in message
...
Harvey wrote:

"Donald Brummel" wrote in message
ink.net...
Sigh, if they "easily beat film" what is point of the newer 4800 dpi
film/slide
scanners?

A 2700 DPI (ie, Nikon Coolscan III) scanner gets you about 28 Meg
per
negative/slide. That is only good for an 8x10. Barely, really just a
nice
5x7.

28Meg? By my calculations a 2700DPI from a 35mm slide etc. would give
something like 3500 x 2500 (give or take), which is about 8.5MPix

you and i think in terms of pixel dimensions, like 3000 x 2000.

some people think image quality is measured by file size.

In that case, the 20D is competitive by Mr. Brummel's standards, it
produces a 24 meg JPEG file...


impossible.

Why would it be impossible?
For a 24 MB Jpeg (assuming best quality, lowest compression) you would
need a 250 MB tif source file. Not even the 20D is capable of that. It
would be about 12,000 x 8,000 pixels, or 96 megapixels.
--
Petros
Ap' ola prin ipirche o Logos

Harvey posted:

"Petros" wrote in message
...
Skip M posted:
"Crownfield" wrote in message
...
Harvey wrote:

"Donald Brummel" wrote in message
ink.net...
Sigh, if they "easily beat film" what is point of the newer 4800 dpi
film/slide
scanners?

A 2700 DPI (ie, Nikon Coolscan III) scanner gets you about 28 Meg
per
negative/slide. That is only good for an 8x10. Barely, really just a
nice
5x7.

28Meg? By my calculations a 2700DPI from a 35mm slide etc. would give
something like 3500 x 2500 (give or take), which is about 8.5MPix

you and i think in terms of pixel dimensions, like 3000 x 2000.

some people think image quality is measured by file size.

In that case, the 20D is competitive by Mr. Brummel's standards, it
produces a 24 meg JPEG file...


impossible.

Why would it be impossible?
For a 24 MB Jpeg (assuming best quality, lowest compression) you would
need a 250 MB tif source file. Not even the 20D is capable of that. It
would be about 12,000 x 8,000 pixels, or 96 megapixels.
--
Petros
Ap' ola prin ipirche o Logos

In article In1od.161797$hj.99707@fed1read07, says...
You may be able to say it with confidence, but your equipment's limitations
curtail its veracity, as you note in your last paragraph.
Some digital equipment at 8mp, for one reason or another, won't equal the
best of film. Some will, and in some uses, possibly exceed it. I get
better 16x20 images from my 20D than I did from my 1n with Ilford XP-2, a
400 ISO film. Will I get better 16x20s than from Ektar 25? I don't know,
since I can't make that comparison.

--
Skip Middleton
http://www.shadowcatcherimagery.com



Near as I can tell, we "kind of" agree.

The point I was trying (rather poorly I guess) is that we CAN use both
digital & film, without being some kind of "traitor to the cause".

Im sure there are Digital Cameras around that are better than mine, I've SEEN
THEM. (I've even USED a couple) They just aren't suited to my budget and my
work. So in place of them I use FILM when I need better than my digitals can
do.

I COULD have bought the Digital Rebel instead of the Sony F 828 (the Canon
was actually cheaper with the kit lens) BUT the one and only time I used one,
I had dust contamination problems because of the environment in which I tend
to shoot.

Bigger Sensor? YES
Better Picture YES even with fewer pixels.
Did I get MORE of those BETTER pictures? NO!

I had to suspend use of the Rebel because it was getting contaminated with
dust (on the sensor), and my subjects couldn't wait while I cleaned it. So
for that day I simply used FILM...(I never did remove the lens before the
dust problem, so I dont know HOW the dust was getting in, and not owning the
camera kept me from finding/curing the problem)

Perhaps my feelings are based on a difference in philosophy.. I got into
DIGITAL for its flexibility NOT for the instant gratification aspect of it
(though I MUST admit It is a GREAT side benefit!)

I just dont understand the argument "Which Is Better" when we still have BOTH
as a viable means to "GET" our pictures.




--
Larry Lynch
Mystic, Ct.

In article In1od.161797$hj.99707@fed1read07, says...
You may be able to say it with confidence, but your equipment's limitations
curtail its veracity, as you note in your last paragraph.
Some digital equipment at 8mp, for one reason or another, won't equal the
best of film. Some will, and in some uses, possibly exceed it. I get
better 16x20 images from my 20D than I did from my 1n with Ilford XP-2, a
400 ISO film. Will I get better 16x20s than from Ektar 25? I don't know,
since I can't make that comparison.

--
Skip Middleton
http://www.shadowcatcherimagery.com



Near as I can tell, we "kind of" agree.

The point I was trying (rather poorly I guess) is that we CAN use both
digital & film, without being some kind of "traitor to the cause".

Im sure there are Digital Cameras around that are better than mine, I've SEEN
THEM. (I've even USED a couple) They just aren't suited to my budget and my
work. So in place of them I use FILM when I need better than my digitals can
do.

I COULD have bought the Digital Rebel instead of the Sony F 828 (the Canon
was actually cheaper with the kit lens) BUT the one and only time I used one,
I had dust contamination problems because of the environment in which I tend
to shoot.

Bigger Sensor? YES
Better Picture YES even with fewer pixels.
Did I get MORE of those BETTER pictures? NO!

I had to suspend use of the Rebel because it was getting contaminated with
dust (on the sensor), and my subjects couldn't wait while I cleaned it. So
for that day I simply used FILM...(I never did remove the lens before the
dust problem, so I dont know HOW the dust was getting in, and not owning the
camera kept me from finding/curing the problem)

Perhaps my feelings are based on a difference in philosophy.. I got into
DIGITAL for its flexibility NOT for the instant gratification aspect of it
(though I MUST admit It is a GREAT side benefit!)

I just dont understand the argument "Which Is Better" when we still have BOTH
as a viable means to "GET" our pictures.




--
Larry Lynch
Mystic, Ct.

You may be able to say it with confidence, but your equipment's
limitations curtail its veracity, as you note in your last paragraph.
Some digital equipment at 8mp, for one reason or another, won't equal the
best of film. Some will, and in some uses, possibly exceed it. I get
better 16x20 images from my 20D than I did from my 1n with Ilford XP-2, a
400 ISO film. Will I get better 16x20s than from Ektar 25? I don't know,
since I can't make that comparison.

--
Skip Middleton
http://www.shadowcatcherimagery.com

Ektar 25! Oh how I miss thee! Love my 20D but have a moving water fetish
that ISO 25 was just perfect for!

D
www.pbase.com/fitpix

In article ,
says...
Ektar 25! Oh how I miss thee! Love my 20D but have a moving water fetish
that ISO 25 was just perfect for!

D
www.pbase.com/fitpix






I dont know as I'de call it a "fetish" but I also LOVE to photograph "moving
Water" scenes.

Living near the ocean, and working for a water company give me the oportunity
to shoot a lot of both small streams and large bodies of water.


--
Larry Lynch
Mystic, Ct.

In article ,
says...
Ektar 25! Oh how I miss thee! Love my 20D but have a moving water fetish
that ISO 25 was just perfect for!

D
www.pbase.com/fitpix






I dont know as I'de call it a "fetish" but I also LOVE to photograph "moving
Water" scenes.

Living near the ocean, and working for a water company give me the oportunity
to shoot a lot of both small streams and large bodies of water.


--
Larry Lynch
Mystic, Ct.

On Sat, 20 Nov 2004 22:20:01 GMT, John Miller wrote:

KBob wrote:
Certainly 8 Mp could beat the pants off of 35mm film, if it was 8 Mpx
in a high-end pro camera with a critically fine lens. However, this
simply isn't the case when we speak of "8 Mpx cameras." For that
matter, the D100, D70 etc. easily beat film, but you will be
disappointed with the dinky-sensored consumer cameras that tout 8 Mpx,
since a large portion of their resolution is lost due to bleedover and
other anomalies associated with the tiny sensor size.

Here's a question from another angle (and if it's been thrashed out
before, my apologies): Given a full-frame (24mm x 36mm) sensor, how many
Mpx are required to take full advantage of today's best lenses? Being
retired and now using my gear for pleasure, not for income, I'm kind of
holding out for ~12 Mpx, but that's really just a S.W.A.G. What are the
facts?

That's hard to answer, since at least with my experience in using the
Kodak 14n (14 Mpx F-F), a good many popular lenses are very challenged
when using this camera. You might not think so, since the sensor's
resolution is inherently limited to about 60 l/mm, but this is
sufficient to reveal a lack of critical "sharpness" even on some
highly-touted Nikkors. A falloff of resolution seems to create a much
more noticeable visual problem with digital as opposed to film. For
example, my 80-200mm f/2.8 is highly regarded, but fails to deliver
more than about 48 l/mm when wide open at its 200mm setting, rendering
its images at this setting unsuited to enlargements beyond about 8X10.
Both of my recent 50mm Nikkor primes (f/1.8 and f/1.4) show problems
wide open--the f/1.8 goes soft, and the f/1.4 has contrast falloff.
In fact, of the 40 or so Nikkors in my collection, there are only a
couple that don't have problems at some settings (apart from
diffraction limiting).

It's my guess that when Nikon's new D2X with 12 Mpx hits the street,
we'll see a lot of owners shedding their coveted zoom lenses and
looking for primes, at least if they wish to take advantage of this
very high-res sensor.

Also we shouldn't forget the constraints that digital sensors put on
lenses. The exit pupil characteristics of many lenses render them
poorly suited to digital use, and usually this is due to having an
optical formula that places the exit pupil overly close to the "film"
plane, thus creating an angle of light incidence that is not properly
accepted by the sensor and its antialiasing system (microlenses).
Most retrofocus lenses work reasonably well, but their design is
intended to provide clearance for the mirror swing, and in some cases
this is still insufficient to provide the relatively normal incidence
required at the sensor/microlens surface.

So to answer your question more directly, if you were to use lenses
that exhibit high resolution, say in excess of 100 l/mm, then you
could profit from a full-frame 35mm sensor of about 20 Mpx or even
more. From a practical standpoint, however, you always should take
this Mpx figure back to the print sizes you intend to use, and when
you consider the inherent spreading of the printed image and finite
resolution that can be realized with an ink-jet printout, you're left
with a simple formula that can be used to determine how many pixels
are required to deliver a print that will be regarded under close
inspection as "sharp." This comes close to 0.05 Mpx per square inch,
for prints of normal proportions. If it were possible to print at
higher resolution than the technology permits today, this figure could
be doubled to about 0.1 Mpx per square inch, in which case we would
have what is generally considered "critically sharp" prints.

High-res digital backs on mid-format cameras such as Hassleblads may
not be the answer, either. Measurements of lens resolution for a wide
range of lenses for these cameras show them to be only moderately good
resolvers, probably due to the compromises required in achieving the
added coverage.

-KBob

On Sat, 20 Nov 2004 22:20:01 GMT, John Miller wrote:

KBob wrote:
Certainly 8 Mp could beat the pants off of 35mm film, if it was 8 Mpx
in a high-end pro camera with a critically fine lens. However, this
simply isn't the case when we speak of "8 Mpx cameras." For that
matter, the D100, D70 etc. easily beat film, but you will be
disappointed with the dinky-sensored consumer cameras that tout 8 Mpx,
since a large portion of their resolution is lost due to bleedover and
other anomalies associated with the tiny sensor size.

Here's a question from another angle (and if it's been thrashed out
before, my apologies): Given a full-frame (24mm x 36mm) sensor, how many
Mpx are required to take full advantage of today's best lenses? Being
retired and now using my gear for pleasure, not for income, I'm kind of
holding out for ~12 Mpx, but that's really just a S.W.A.G. What are the
facts?

That's hard to answer, since at least with my experience in using the
Kodak 14n (14 Mpx F-F), a good many popular lenses are very challenged
when using this camera. You might not think so, since the sensor's
resolution is inherently limited to about 60 l/mm, but this is
sufficient to reveal a lack of critical "sharpness" even on some
highly-touted Nikkors. A falloff of resolution seems to create a much
more noticeable visual problem with digital as opposed to film. For
example, my 80-200mm f/2.8 is highly regarded, but fails to deliver
more than about 48 l/mm when wide open at its 200mm setting, rendering
its images at this setting unsuited to enlargements beyond about 8X10.
Both of my recent 50mm Nikkor primes (f/1.8 and f/1.4) show problems
wide open--the f/1.8 goes soft, and the f/1.4 has contrast falloff.
In fact, of the 40 or so Nikkors in my collection, there are only a
couple that don't have problems at some settings (apart from
diffraction limiting).

It's my guess that when Nikon's new D2X with 12 Mpx hits the street,
we'll see a lot of owners shedding their coveted zoom lenses and
looking for primes, at least if they wish to take advantage of this
very high-res sensor.

Also we shouldn't forget the constraints that digital sensors put on
lenses. The exit pupil characteristics of many lenses render them
poorly suited to digital use, and usually this is due to having an
optical formula that places the exit pupil overly close to the "film"
plane, thus creating an angle of light incidence that is not properly
accepted by the sensor and its antialiasing system (microlenses).
Most retrofocus lenses work reasonably well, but their design is
intended to provide clearance for the mirror swing, and in some cases
this is still insufficient to provide the relatively normal incidence
required at the sensor/microlens surface.

So to answer your question more directly, if you were to use lenses
that exhibit high resolution, say in excess of 100 l/mm, then you
could profit from a full-frame 35mm sensor of about 20 Mpx or even
more. From a practical standpoint, however, you always should take
this Mpx figure back to the print sizes you intend to use, and when
you consider the inherent spreading of the printed image and finite
resolution that can be realized with an ink-jet printout, you're left
with a simple formula that can be used to determine how many pixels
are required to deliver a print that will be regarded under close
inspection as "sharp." This comes close to 0.05 Mpx per square inch,
for prints of normal proportions. If it were possible to print at
higher resolution than the technology permits today, this figure could
be doubled to about 0.1 Mpx per square inch, in which case we would
have what is generally considered "critically sharp" prints.

High-res digital backs on mid-format cameras such as Hassleblads may
not be the answer, either. Measurements of lens resolution for a wide
range of lenses for these cameras show them to be only moderately good
resolvers, probably due to the compromises required in achieving the
added coverage.

-KBob

Fitpix wrote:


Ektar 25! Oh how I miss thee! Love my 20D but have a moving water fetish

Try an enema...


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