Digital BW, The Print

Could someone comment on the current state of mind 
concerning the difference between printing at 360 dpi or 300? 
I was under the impression that anything above 300 was going 
above and beyond the call of duty.  One of my sources being
John Caponigro's book "Adobe Photoshop Master Class", which 
I realize is probably somewhat "aged" in the ever changing world 
of digital prints.  thanks,  doug

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "nakalele2" 
<floydd001@h...> wrote:
> Could someone comment on the current state of mind 
> concerning the difference between printing at 360 dpi or 300? 
> I was under the impression that anything above 300 was going 
> above and beyond the call of duty.  One of my sources being
> John Caponigro's book "Adobe Photoshop Master Class", which 
> I realize is probably somewhat "aged" in the ever changing world 
> of digital prints.  thanks,  doug

Doug:  Printing dpi/ppi totally depends on your images, printer,  
artistic intent, and taste.  Use what works for you.

Jeff Randall

I did a series of tests with my printer, a 1270 using the Epson
driver.  Short answer: 360 or 720ppi print noticablely better 
than any other resolutions.

Long answer:
I'm fairly picky.  I usually don't enlarge beyond 4-5x in the darkroom.
I look at prints from 6" away.

The _image_ resolutions I tested were: 840, 780, 720, 660, 600, 540,
480, 420, 360, 300, 240, 180ppi, 8-bit grayscale images printed from
Illustrator.  I created the different resolution versions by starting at 
840ppi, and downsampling to each successively lower resolution in 
Photoshop.  My test  image had some thin slightly diagonal lines 
(wood joints) which helped identify differences.  The thing that 
immediately stands out is moiring(?) in these lines at image resolutions
other than 360 or 720ppi. 420 and 300ppi, for example, look _way_ 
worse than 360ppi.  In other, more organic areas (rock texture), 
pixelation is  noticable at 240ppi, but not at 300ppi (naked eye).

As for the difference between 360 and 720ppi, I see no difference to
my naked eye, but under a 7x loupe, can see faint pixelation in certain
areas (sharp, diagonal lines) in the 360ppi file that are smooth in the 
720ppi one.

I'm guessing this information would apply to other Epson printers as
well, but you should probably test your own printer/driver combination.

Anyone else have experiences to support/contrast this?

BH 

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "nakalele2" 
<floydd001@h...> wrote:

> Could someone comment on the current state of mind 
> concerning the difference between printing at 360 dpi or 300? 
> I was under the impression that anything above 300 was going 
> above and beyond the call of duty.  One of my sources being
> John Caponigro's book "Adobe Photoshop Master Class", which 
> I realize is probably somewhat "aged" in the ever changing world 
> of digital prints.  thanks,  doug

BH,

> I did a series of tests with my printer, a 1270 using the Epson
> driver.  Short answer: 360 or 720ppi print noticeable better
> than any other resolutions.
>
> Long answer:
> I'm fairly picky.  I usually don't enlarge beyond 4-5x in the darkroom.
> I look at prints from 6" away.
>
> The _image_ resolutions I tested were: 840, 780, 720, 660, 600, 540,
> 480, 420, 360, 300, 240, 180ppi, 8-bit grayscale images printed from
> Illustrator.  I created the different resolution versions by starting at
> 840ppi, and downsampling to each successively lower resolution in
> Photoshop.

How do you know the downsampling isn't causing the visual difference in the
printout?

> My test  image had some thin slightly diagonal lines
> (wood joints) which helped identify differences.  The thing that
> immediately stands out is moiring(?) in these lines at image resolutions
> other than 360 or 720ppi.

What was the actual original image scan resolution?

> Anyone else have experiences to support/contrast this?

My tests show that scanning at the native optical resolution of the scanner,
and resizing the image without decimating the image (resampling) yields
noticeably better results than resampling.

Did you try printing one with no resampling?

Regards,

Austin

Austin, thanks for asking - replies inline...

> BH,
> 
> > I did a series of tests with my printer, a 1270 using the Epson
> > driver.  Short answer: 360 or 720ppi print noticeable better
> > than any other resolutions.
> >
> > Long answer:
> > I'm fairly picky.  I usually don't enlarge beyond 4-5x in the darkroom.
> > I look at prints from 6" away.
> >
> > The _image_ resolutions I tested were: 840, 780, 720, 660, 600, 540,
> > 480, 420, 360, 300, 240, 180ppi, 8-bit grayscale images printed from
> > Illustrator.  I created the different resolution versions by starting at
> > 840ppi, and downsampling to each successively lower resolution in
> > Photoshop.
> 
> How do you know the downsampling isn't causing the visual difference in the
> printout?

The image files show no artifacts or moire on screen at 100% pixels. 

> 
> > My test  image had some thin slightly diagonal lines
> > (wood joints) which helped identify differences.  The thing that
> > immediately stands out is moiring(?) in these lines at image resolutions
> > other than 360 or 720ppi.
> 
> What was the actual original image scan resolution?

It was a 6x7 TMX neg scanned @ 3200ppi on an Epson 3200, no "Epson sharpening" 
applied.
> 
> > Anyone else have experiences to support/contrast this?
> 
> My tests show that scanning at the native optical resolution of the scanner,
> and resizing the image without decimating the image (resampling) yields
> noticeably better results than resampling.
> 
> Did you try printing one with no resampling?

No, do you mean setting the print size to various resolutions, and printing each? 
(Each test would be at a different magnification)  I'll give this a try.

- Brian

> 
> Regards,
> 
> Austin

Hi,

> Austin, thanks for asking - replies inline...
>
> > BH,
> >
> > > I did a series of tests with my printer, a 1270 using the Epson
> > > driver.  Short answer: 360 or 720ppi print noticeable better
> > > than any other resolutions.
> > >
> > > Long answer:
> > > I'm fairly picky.  I usually don't enlarge beyond 4-5x in the
> darkroom.
> > > I look at prints from 6" away.
> > >
> > > The _image_ resolutions I tested were: 840, 780, 720, 660, 600, 540,
> > > 480, 420, 360, 300, 240, 180ppi, 8-bit grayscale images printed from
> > > Illustrator.  I created the different resolution versions by
> starting at
> > > 840ppi, and downsampling to each successively lower resolution in
> > > Photoshop.
> >
> > How do you know the downsampling isn't causing the visual
> difference in the
> > printout?
>
> The image files show no artifacts or moire on screen at 100% pixels.

OK...but that doesn't mitigate that this is a possibility.

> >
> > > My test  image had some thin slightly diagonal lines
> > > (wood joints) which helped identify differences.  The thing that
> > > immediately stands out is moiring(?) in these lines at image
> resolutions
> > > other than 360 or 720ppi.
> >
> > What was the actual original image scan resolution?
>
> It was a 6x7 TMX neg scanned @ 3200ppi on an Epson 3200, no
> "Epson sharpening"
> applied.

But what was it printed at, with no downsampling/resampling etc?

> > > Anyone else have experiences to support/contrast this?
> >
> > My tests show that scanning at the native optical resolution of
> the scanner,
> > and resizing the image without decimating the image (resampling) yields
> > noticeably better results than resampling.
> >
> > Did you try printing one with no resampling?
>
> No, do you mean setting the print size to various resolutions,
> and printing each?
> (Each test would be at a different magnification)  I'll give this a try.

No, simple as printing it the same size as the other prints you made, just
leaving the PPI to the printer fall where it may.

Regards,

Austin

> Hi,
> 
> > Austin, thanks for asking - replies inline...
> >
> > > BH,
> > >
> > > > I did a series of tests with my printer, a 1270 using the Epson
> > > > driver.  Short answer: 360 or 720ppi print noticeable better
> > > > than any other resolutions.
> > > >
> > > > Long answer:
> > > > I'm fairly picky.  I usually don't enlarge beyond 4-5x in the
> > darkroom.
> > > > I look at prints from 6" away.
> > > >
> > > > The _image_ resolutions I tested were: 840, 780, 720, 660, 600, 540,
> > > > 480, 420, 360, 300, 240, 180ppi, 8-bit grayscale images printed from
> > > > Illustrator.  I created the different resolution versions by
> > starting at
> > > > 840ppi, and downsampling to each successively lower resolution in
> > > > Photoshop.
> > >
> > > How do you know the downsampling isn't causing the visual
> > difference in the
> > > printout?
> >
> > The image files show no artifacts or moire on screen at 100% pixels.
> 
> OK...but that doesn't mitigate that this is a possibility.
> 
> > >
> > > > My test  image had some thin slightly diagonal lines
> > > > (wood joints) which helped identify differences.  The thing that
> > > > immediately stands out is moiring(?) in these lines at image
> > resolutions
> > > > other than 360 or 720ppi.
> > >
> > > What was the actual original image scan resolution?
> >
> > It was a 6x7 TMX neg scanned @ 3200ppi on an Epson 3200, no
> > "Epson sharpening"
> > applied.
> 
> But what was it printed at, with no downsampling/resampling etc?
> 
> > > > Anyone else have experiences to support/contrast this?
> > >
> > > My tests show that scanning at the native optical resolution of
> > the scanner,
> > > and resizing the image without decimating the image (resampling) yields
> > > noticeably better results than resampling.
> > >
> > > Did you try printing one with no resampling?
> >
> > No, do you mean setting the print size to various resolutions,
> > and printing each?
> > (Each test would be at a different magnification)  I'll give this a try.
> 
> No, simple as printing it the same size as the other prints you made, just
> leaving the PPI to the printer fall where it may.

Ah - I understand now.  At the test's printed size, the image resolution would have 
been 
2400 ppi.  Making a print from this resolution shows no moire effect.  Of course, the 
image is only ~3x3.6"...  I also tried printing a small area of the 
image with no resizing at a particularly bad resolution: 540ppi.  This print shows the 
moire as well, although it is somewhat obscured by the softness of the image at this 
magnification.  

- Brian

> Ah - I understand now.  At the test's printed size, the image
> resolution would have
> been
> 2400 ppi.  Making a print from this resolution shows no moire
> effect.  Of course, the
> image is only ~3x3.6"...  I also tried printing a small area of the
> image with no resizing at a particularly bad resolution: 540ppi.
> This print shows the
> moire as well, although it is somewhat obscured by the softness
> of the image at this
> magnification.

Hi Brian,

I don't think we're in sync yet.  What size prints are you making with your
resampled images?  What I am suggesting is you make that same size print as
that, from the original scan, not resampling...  And if you are making 3" x
3.6" prints, well, don't do that!  Make 8x10, and compare using that.  Even
13" x 19" for that matter.  What is the source negative size BTW?

Also, are we talking color or B&W?

Austin

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Austin
Franklin" 
<darkroom@i...> wrote:
> > Ah - I understand now.  At the test's printed size, the image
> > resolution would have
> > been
> > 2400 ppi.  Making a print from this resolution shows no moire
> > effect.  Of course, the
> > image is only ~3x3.6"...  I also tried printing a small area of
the
> > image with no resizing at a particularly bad resolution: 540ppi.
> > This print shows the
> > moire as well, although it is somewhat obscured by the softness
> > of the image at this
> > magnification.
> 
> Hi Brian,
> 
> I don't think we're in sync yet.  What size prints are you making
with your
> resampled images?  What I am suggesting is you make that same size
print as
> that, from the original scan, not resampling...  And if you are
making 3" x
> 3.6" prints, well, don't do that!  Make 8x10, and compare using
that.  Even
> 13" x 19" for that matter.  What is the source negative size BTW?
> 
> Also, are we talking color or B&W?

Austin,

Sorry if I wasn't clear in my earlier post:  this was a 6x7 TMX neg
scanned on an Epson 
3200.  The reason I initially started this test was that I noticed
some interference in 
diagonal lines in a full-resolution print ~8x10in. @ 880ppi (as you
suggested above).  By 
downsampling the image to 720ppi, the patterns were eliminated.  So,
I decided to try 
other image resolutions, to see how the printer resolution and file
resolution interacted.  
For the series of resolution tests, I used a smaller print
magnification, to illustrate the 
effect with even sharper (less magnified) detail/lines in the image. 
The print size I tested 
was ~3x3.6, which with full resolution from the scan, would have a
pixel resolution of 
2200ppi.

I think the important thing to take away from this experiment is that
it's useful to test 
ones own film/scanner/file size/print size/print driver/printer/paper
combination for 
the optimum combination.  In my case, I noticed interference (moire)
when printing file 
resolutions which are not multiples of the printers hardware
resolution.  (although the 
moire effect becomes less noticeable with higher image resolutions,
say >800ppi)

Brian