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ISO Resolution Test Chart available for download

 
 
Stephen H. Westin
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      10-14-2004

Folks,

Do you know the fancy ISO 12233 test chart that is commonly used for
resolution tests of digital cameras? Did you ever want one of your own?
Well, now you can have the poor man's version. Point your browser to

<http://www.graphics.cornell.edu/~westin/res-chart.html>,

where you can download a PDF file to print a chart on your own
printer. Of course, the chart you print won't have the dimensional
and tonal control of the real charts available from Sine Patterns and
others (<http://www.i3a.org/iso_test_charts.html>), but then it
doesn't cost over a hundred bucks, either.

Enjoy!

--
-Stephen H. Westin
Any information or opinions in this message are mine: they do not
represent the position of Cornell University or any of its sponsors.

 
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Bart van der Wolf
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      10-14-2004

"Stephen H. Westin" <westin*(E-Mail Removed)> wrote in
message news:(E-Mail Removed)...
SNIP
> Enjoy!


Thanks for the effort.

Bart

 
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Gene Palmiter
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      10-14-2004
I think you are asking the impossible. How would you print it out? When you
print it you will be checking the resolution of your printer...and then you
will photograph it to see the resolution of your camera? I think you need to
find a place to buy one.


"Bart van der Wolf" <(E-Mail Removed)> wrote in message
news:416edd51$0$37789$(E-Mail Removed)4all.nl...
>
> "Stephen H. Westin" <westin*(E-Mail Removed)> wrote in
> message news:(E-Mail Removed)...
> SNIP
> > Enjoy!

>
> Thanks for the effort.
>
> Bart
>



 
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Ryadia
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      10-14-2004
Gene Palmiter wrote:
> I think you are asking the impossible. How would you print it out? When you
> print it you will be checking the resolution of your printer...and then you
> will photograph it to see the resolution of your camera? I think you need to
> find a place to buy one.
>
>

The point is... This fellow went to the trouble of pointing to the
source and adding it is a poor cousin to the real thing which costs
several hunderd bucks.

I printed it on my HP designjet 130 at an interpolated size of 200%. Now
when I photograph this print, I can see the difference in resolution
between an Olympus digicam and a 20D Canon with glaring detail.

FWIW I think it's a simple way to check the resolution of a lens too.
Certainly the Canon kit lens compared to a 120~300 f2.8 Sigma lens is
noticable. I haven't checked the others in my kit but I will when I get
time. This chart might not be the "real thing" but it is most definitely
better than nothing - for nothing and... It has helped me to better
understand 2 of my lenses!

Ryadia
 
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Bart van der Wolf
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      10-14-2004

"Gene Palmiter" <(E-Mail Removed)> wrote in message
news:5_Cbd.662$Nj1.525@trndny04...
> I think you are asking the impossible. How would you print it out?
> When you print it you will be checking the resolution of your

printer...
> and then you will photograph it to see the resolution of your

camera?
> I think you need to find a place to buy one.


Obviously (for those who've tried) the target needs to be printed at
the maximum resolution the printer allows, at the indicated size, as
all text and other bi-tonal line-art requires *much* higher
resolution (1200+ ppi) than continuous tone does.

A much easier/better target for pure resolution/MTF is a slanted edge
pattern which is e.g. printed and only then rotated for imaging.

Bart

 
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Bart van der Wolf
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      10-14-2004

"Ryadia" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
SNIP
> FWIW I think it's a simple way to check the resolution of a
> lens too. Certainly the Canon kit lens compared to a 120~300
> f2.8 Sigma lens is noticable. I haven't checked the others in my
> kit but I will when I get time. This chart might not be the "real
> thing" but it is most definitely better than nothing - for nothing
> and... It has helped me to better understand 2 of my lenses!


If you *really* want to get a grip on things like "optimal" aperture,
best lens, camera shake or tripod quality, mirror slap, color
accuracy, noise, etc., etc., I suggest http://www.imatest.com .

Bart

 
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Charles Schuler
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      10-15-2004
Worthwhile. Thanks!


 
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George Preddy
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      10-16-2004
"Bart van der Wolf" <(E-Mail Removed)> wrote in message news:<416f08d8$0$48933$(E-Mail Removed)4all.nl>...
> "Gene Palmiter" <(E-Mail Removed)> wrote in message
> news:5_Cbd.662$Nj1.525@trndny04...
> > I think you are asking the impossible. How would you print it out?
> > When you print it you will be checking the resolution of your

> printer...
> > and then you will photograph it to see the resolution of your

> camera?
> > I think you need to find a place to buy one.

>
> Obviously (for those who've tried) the target needs to be printed at
> the maximum resolution the printer allows, at the indicated size, as
> all text and other bi-tonal line-art requires *much* higher
> resolution (1200+ ppi) than continuous tone does.
>
> A much easier/better target for pure resolution/MTF is a slanted edge
> pattern which is e.g. printed and only then rotated for imaging.


Why would that matter, when both the printer and the camera can
interpolate black and white contingous lines accurately all day long
anyway?

The chart is the standard, he's right, because Bayer manufactures will
knock off any reviewer who so much as thinks about publishing full
color resolution test. They need a 300% setback vs color film and
Foveon like they need a another faulty firmware release.
 
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Bart van der Wolf
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      10-16-2004

"George Preddy" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) om...
> "Bart van der Wolf" <(E-Mail Removed)> wrote in message

news:<416f08d8$0$48933$(E-Mail Removed)4all.nl>...
SNIP
> > A much easier/better target for pure resolution/MTF is a
> > slanted edge pattern which is e.g. printed and only then
> > rotated for imaging.

>
> Why would that matter, when both the printer and the camera
> can interpolate black and white contingous lines accurately all
> day long anyway?


Interpolation doesn't create resolution, and produces a lower
modulation in an MTF. By aligning the edge with the printer driver's
positioning raster grid, interpolation is avoided alltogether.

What's more, the slanted edge methods allows to sub-sample beyond the
Nyquist frequency, which allows to predict aliasing tendency. Other
methods cannot distinguish between signal and alias.

Bart

 
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George Preddy
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      10-17-2004
"Bart van der Wolf" <(E-Mail Removed)> wrote in message news:<4170fa10$0$78279$(E-Mail Removed)4all.nl>...
> "George Preddy" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed) om...
> > "Bart van der Wolf" <(E-Mail Removed)> wrote in message

> news:<416f08d8$0$48933$(E-Mail Removed)4all.nl>...
> SNIP
> > > A much easier/better target for pure resolution/MTF is a
> > > slanted edge pattern which is e.g. printed and only then
> > > rotated for imaging.

> >
> > Why would that matter, when both the printer and the camera
> > can interpolate black and white contingous lines accurately all
> > day long anyway?

>
> Interpolation doesn't create resolution, and produces a lower
> modulation in an MTF. By aligning the edge with the printer driver's
> positioning raster grid, interpolation is avoided alltogether.
>
> What's more, the slanted edge methods allows to sub-sample beyond the
> Nyquist frequency, which allows to predict aliasing tendency. Other
> methods cannot distinguish between signal and alias.\


You point is that it is junk.
 
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