8Mp Digital The Theoretical 35mm Quality Equivelant

"Petros" wrote in message
...
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

Sorry, bud, you're wrong. The native file from my 20D, Jpeg Large/Fine is
23.4M. It produces a RAW file that when converted to Tiff 16 bit that is
46.8M. I'd threaten to send it you, but it's too large for my server. ;-)

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

"Petros" wrote in message
...
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

Sorry, bud, you're wrong. The native file from my 20D, Jpeg Large/Fine is
23.4M. It produces a RAW file that when converted to Tiff 16 bit that is
46.8M. I'd threaten to send it you, but it's too large for my server. ;-)

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

"Petros" wrote in message
...
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

Sorry, bud, you're wrong. The native file from my 20D, Jpeg Large/Fine is
23.4M. It produces a RAW file that when converted to Tiff 16 bit that is
46.8M. I'd threaten to send it you, but it's too large for my server. ;-)

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

Yeah, me too...

--
Skip Middleton
http://www.shadowcatcherimagery.com
"Fitpix" wrote in message
...
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

Yeah, me too...

--
Skip Middleton
http://www.shadowcatcherimagery.com
"Fitpix" wrote in message
...
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 message 8A5od.161889$hj.22322@fed1read07,
"Skip M" wrote:

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

1) These digital SLRs are over-rated in ISO, compared to film. Using an
external meter, you will expose darker than with the camera's metering.
Therefore, you could say that ISO 100 on the 20D is like ISO 64 with
film.

2) There is lots of dynamic headroom in the 20D. In low-contrast
conditions (like an overcast day), I often set the EC to +2 without
blowing out highlights. That brings us to ISO 16, compared to film.

3) ND filters.
--


John P Sheehy

In message 8A5od.161889$hj.22322@fed1read07,
"Skip M" wrote:

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

1) These digital SLRs are over-rated in ISO, compared to film. Using an
external meter, you will expose darker than with the camera's metering.
Therefore, you could say that ISO 100 on the 20D is like ISO 64 with
film.

2) There is lots of dynamic headroom in the 20D. In low-contrast
conditions (like an overcast day), I often set the EC to +2 without
blowing out highlights. That brings us to ISO 16, compared to film.

3) ND filters.
--


John P Sheehy

In message 8A5od.161889$hj.22322@fed1read07,
"Skip M" wrote:

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

1) These digital SLRs are over-rated in ISO, compared to film. Using an
external meter, you will expose darker than with the camera's metering.
Therefore, you could say that ISO 100 on the 20D is like ISO 64 with
film.

2) There is lots of dynamic headroom in the 20D. In low-contrast
conditions (like an overcast day), I often set the EC to +2 without
blowing out highlights. That brings us to ISO 16, compared to film.

3) ND filters.
--


John P Sheehy

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

Sorry, bud, you're wrong. The native file from my 20D, Jpeg Large/Fine is
23.4M. It produces a RAW file that when converted to Tiff 16 bit that is
46.8M. I'd threaten to send it you, but it's too large for my server. ;-)


From http://www.digitalreview.ca/cams/CanonEOS20D.shtml
(Canon USA seems to be down, and Canon UK does not give file size info)

File sizes:

(1) Large/Fine: Approx. 3.6MB (3504 x 2336 pixels)
(2) Large/Normal: Approx. 1.8MB (3504 x 2336 pixels)
(3) Medium/Fine: Approx. 2.2MB (2544 x 1696 pixels)
(4) Medium/Normal: Approx. 1.1MB (2544 x 1696 pixels)
(5) Small/Fine: Approx. 1.2MB (1728 x 1152 pixels)
(6) Small/Normal: Approx. 0.6MB (1728 x 1152 pixels)
(7) RAW: Approx. 8.7MB (3504 x 2336 pixels)
* Exact file sizes depend on the subject, ISO speed, processing
parameters, etc.

Actually, you're the one who's wrong An uncompressed 24 bit TIF file
@ 3504x2336 px will be 23.42 MegaBytes, which on average will give
about the 3.6 MegaByte JPEG with EXIF info mentioned at the top of this
list. If you convert your RAW file to 48 bit TIF then you can have a
large file, but one that you can't do much with on a commercial printer
or imager. A 48 bit TIF is really only good at the editing stage since
you can do more color manipulation with less damage. When you go to
print or to create a JPG file, you need to convert to 24 bit. (unless
you're printing to your desktop printer, in which case your image app
is converting it for you)

So

1)Your 8 MegaPixel camera is not outputting a 23.4 MegaByte JPG file
because it's technically impossible from that camera,

2)The RAW file from your camera is not a JPG or TIF, but a lossless
compressed 48 bit file that can be converted to a 46.8 MegaByte 48 bit
uncompressed TIF or a 23.4 MegaByte 24 bit TIF,

3)You do not have a 96 MegaPixel camera

--
Petros
Ap' ola prin ipirche o Logos

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

Sorry, bud, you're wrong. The native file from my 20D, Jpeg Large/Fine is
23.4M. It produces a RAW file that when converted to Tiff 16 bit that is
46.8M. I'd threaten to send it you, but it's too large for my server. ;-)


From http://www.digitalreview.ca/cams/CanonEOS20D.shtml
(Canon USA seems to be down, and Canon UK does not give file size info)

File sizes:

(1) Large/Fine: Approx. 3.6MB (3504 x 2336 pixels)
(2) Large/Normal: Approx. 1.8MB (3504 x 2336 pixels)
(3) Medium/Fine: Approx. 2.2MB (2544 x 1696 pixels)
(4) Medium/Normal: Approx. 1.1MB (2544 x 1696 pixels)
(5) Small/Fine: Approx. 1.2MB (1728 x 1152 pixels)
(6) Small/Normal: Approx. 0.6MB (1728 x 1152 pixels)
(7) RAW: Approx. 8.7MB (3504 x 2336 pixels)
* Exact file sizes depend on the subject, ISO speed, processing
parameters, etc.

Actually, you're the one who's wrong An uncompressed 24 bit TIF file
@ 3504x2336 px will be 23.42 MegaBytes, which on average will give
about the 3.6 MegaByte JPEG with EXIF info mentioned at the top of this
list. If you convert your RAW file to 48 bit TIF then you can have a
large file, but one that you can't do much with on a commercial printer
or imager. A 48 bit TIF is really only good at the editing stage since
you can do more color manipulation with less damage. When you go to
print or to create a JPG file, you need to convert to 24 bit. (unless
you're printing to your desktop printer, in which case your image app
is converting it for you)

So

1)Your 8 MegaPixel camera is not outputting a 23.4 MegaByte JPG file
because it's technically impossible from that camera,

2)The RAW file from your camera is not a JPG or TIF, but a lossless
compressed 48 bit file that can be converted to a 46.8 MegaByte 48 bit
uncompressed TIF or a 23.4 MegaByte 24 bit TIF,

3)You do not have a 96 MegaPixel camera

--
Petros
Ap' ola prin ipirche o Logos