Commercial print resolution about 5 megapixels?

On 2015-05-12 01:47:32 +0000, PeterN said:

On 5/11/2015 8:29 PM, John McWilliams wrote:
On 5/11/15 PDT 12:28 PM, PeterN wrote:

snip


The color space is not an issue because I use the ICC profile for that
printer, and the paper I want for printing.
I size my prints for 12 x 18 @ 350 ppi. Perhaps to make it clear I
wanted to know if I gained anything by sizing 12 x 18 @ a significantly
higher ppi.

I do, and can, on my Epson 3800 printer. Higher PPI, and higher DPI
settings in the printer produce a higher quality print. But it takes a
lot longer, uses more ink, and in some instances, is a waste depending
on the size and nature of the image.

Your printer may give you guidance here, or he may just resize the
pixels to whatever he wants to if you give him a 720 ppi image.


Thanks.
I will try it with the next batch and see if it makes a difference. My
guess is that it should. On extreme crops I have been getting some
pixelation when I resize to 12 x 18, though the original images are
sharp.

....but just how are extreme are your crops? There comes a time when
even the sharpest images with a small section cropped are beyond decent
enlargement, even with Perfect Resize.

Here is an example: This crop from the original is about same
proportion to the original, as the space from bottom of the bird's
head to the top of the chick is to this image.

That tells us very little.

Remember I have 36 mpix to work with.

https://dl.dropboxusercontent.com/u/97242118/feeding%20junior.jpg

....and that image is next to useless for giving any intellegent
assistance. I suspect that you have made a severe crop which has put
you at the outer fringe of the envelope for enlarging to a size you are
aiming for.

What is the actual size of the cropped file? The image you are showing
is approximately 648x400 and I assume at 72ppi.

What method are you using to resize, and what ppi are you using? (I
suggest 360ppi).

The PS CC resize feature should be able to deal with up-sizing from
your fat originals. If not, go to Perfect Resize. If you are getting
pixelation given what you have to work with, then there is something
else that you might be doing wrong.
--
Regards,

Savageduck

On 12/05/2015 1:20 p.m., Savageduck wrote:
On 2015-05-12 01:05:44 +0000, Savageduck said:

On 2015-05-12 00:35:42 +0000, John McWilliams said:
On 5/11/15 PDT 3:22 PM, Savageduck wrote:
On 2015-05-11 21:58:42 +0000, Me said:
On 12/05/2015 4:36 a.m., Floyd L. Davidson wrote:
Alan Browne wrote:
The numbers are those that apply after cropping and sizing the
image.

So if you crop a 6000 x 4000 image down to 600 x 400
pixels (as an extreme example), then that's all the real
resolution left. At 150 dpi that would be 4 x 2.6
inches as a print.

That is a misconception. First, Epson printers print at
360 *PPI*. They cannot print at 150 *PPI*.

360 ppi is a divisor of the nominal printer dpi setting, 1440, 2880
etc.
I did some very thorough tests with an R1800 to assess resolution for
stereo imaging pairs, on glossy photo paper.
It did resolve more than 360ppi if the printer was sent an image (test
pattern) at precisely 720dpi and 1440dpi. Horizontal (relative to the
direction of paper feed) resolution of full-tones approached 360 lines
per inch. Diagonal and vertical resolution dropped significantly, as
did half-tones, but still easily exceeded 360dpi (180 lpi) overall.
Viewed under a microscope, the ink droplets on the surface are oval -
"stretched" in the direction of print-head travel.
These days I usually print on untextured matte / fine art papers with
an R3880. While output on semi-gloss/pearl papers can be extremely
good, this is where these printers truly shine (IMO).

I get outstanding results with my R2880 on Red River Papers,
particularly their Polar Pearl Metallic and Premuim Gloss PLUS. The
print resolution is set at 360dpi. Lightroom or Photoshop controlling
color with the appropriate paper/printer icc profile set.

My Epson R2880 is set as follows:
Media Type: "Ultra Premium Photo Luster" (that is the Red River
recommendation for Epson photo printers)
Color: 16-bit/channel
Color Settings: Off
Print Quality: SuperFine - 1440dpi

So to press the point, the file is sized with 360dpi and the printer is
left to do its thing at 1440dpi.

The file is 360 PPI, and the printer's setting is 1440 DPI. Trust me
on this. I have corrected Adobe employees on this, but not for a
number of years.

I know, those are the numeric settings I use. Sometimes one can get
careless behind th keyboard. I should have said ppi when setting file
resolution & size. This whole issue can be confusing for those faced
with setting file resolution and printer settings when conflating ppi
& dpi for file size and print output. They serve different purposes.

So If I want a 12"x8" print, I will be looking at a file with ppi set at
360 (that is my default from RAW conversion, either with ACR or LR) and
the dimensions will be 4320 x 2880. That is the file which will be fed
to the R2880 which will churn away at SuperFine - 1440dpi. I could have
selected "SuperPhoto - 5760dpi" but that would be pointless and of
little benefit to the end result in 99% of cases

I wouldn't sweat it too much. With the earlier 13" printers
R1800/2400), they called the 5760dpi "RPM" mode. That was an acronym
for something. But I would use 2880dpi (not 1440) on gloss or
semi-gloss photo papers. There is a difference - and it's not costing
you anything (except time to print). If you want maximum resolution,
check/set print-head alignment reasonably frequently. Disable
bi-directional printing (which also improves alignment) - if you don't
mind waiting longer for the print.
If you're using ICC profiles, then they're made at a specific printer
DPI setting, and are usually named as such. A profile made for 2880dpi
will not be ideal if you print at 1440 dpi - the colours may be slightly
out. Using a microscope, I could see some difference using RPM mode,
but with a loupe, I couldn't.

On Mon, 11 May 2015 17:33:04 -0700, John McWilliams
wrote:

On 5/11/15 PDT 10:30 AM, nospam wrote:
In article , Floyd L. Davidson
wrote:

So if you crop a 6000 x 4000 image down to 600 x 400
pixels (as an extreme example), then that's all the real
resolution left. At 150 dpi that would be 4 x 2.6
inches as a print.

That is a misconception. First, Epson printers print at
360 *PPI*. They cannot print at 150 *PPI*.

if you send it a 150 ppi image, they will.


Floyd has never fully understood the difference between ppi and dpi. I
doubt he ever will.

Epson printers- and there are many- may be able to print at any number
of *DPI*s. Mine does.

What printer do you have?

Input, expressed in pixels, not dots, can have a huge range of *PPI*s. A
fairly standard number of PPI's is 300-360. Sometimes the printer is set
to a DPI of the same number, thus confusing some.

What software are you using to set the DPI? Is it the printer driver
or something else?
--

Regards,

Eric Stevens

On 5/11/15 PDT 9:38 PM, Eric Stevens wrote:
On Mon, 11 May 2015 17:33:04 -0700, John McWilliams
wrote:

On 5/11/15 PDT 10:30 AM, nospam wrote:
In article , Floyd L. Davidson
wrote:

So if you crop a 6000 x 4000 image down to 600 x 400
pixels (as an extreme example), then that's all the real
resolution left. At 150 dpi that would be 4 x 2.6
inches as a print.

That is a misconception. First, Epson printers print at
360 *PPI*. They cannot print at 150 *PPI*.

if you send it a 150 ppi image, they will.


Floyd has never fully understood the difference between ppi and dpi. I
doubt he ever will.

Epson printers- and there are many- may be able to print at any number
of *DPI*s. Mine does.

What printer do you have?

Epson 3800.

Input, expressed in pixels, not dots, can have a huge range of *PPI*s. A
fairly standard number of PPI's is 300-360. Sometimes the printer is set
to a DPI of the same number, thus confusing some.

What software are you using to set the DPI? Is it the printer driver
or something else?

Only the printer can set the DPI, at least that's the only way I know of.

On 5/11/15 PDT 9:20 PM, Me wrote:
On 12/05/2015 1:20 p.m., Savageduck wrote:
On 2015-05-12 01:05:44 +0000, Savageduck said:

On 2015-05-12 00:35:42 +0000, John McWilliams said:
On 5/11/15 PDT 3:22 PM, Savageduck wrote:
On 2015-05-11 21:58:42 +0000, Me said:
On 12/05/2015 4:36 a.m., Floyd L. Davidson wrote:
Alan Browne wrote:
The numbers are those that apply after cropping and sizing the
image.

So if you crop a 6000 x 4000 image down to 600 x 400
pixels (as an extreme example), then that's all the real
resolution left. At 150 dpi that would be 4 x 2.6
inches as a print.

That is a misconception. First, Epson printers print at
360 *PPI*. They cannot print at 150 *PPI*.

360 ppi is a divisor of the nominal printer dpi setting, 1440, 2880
etc.
I did some very thorough tests with an R1800 to assess resolution for
stereo imaging pairs, on glossy photo paper.
It did resolve more than 360ppi if the printer was sent an image
(test
pattern) at precisely 720dpi and 1440dpi. Horizontal (relative to
the
direction of paper feed) resolution of full-tones approached 360
lines
per inch. Diagonal and vertical resolution dropped significantly, as
did half-tones, but still easily exceeded 360dpi (180 lpi) overall.
Viewed under a microscope, the ink droplets on the surface are oval -
"stretched" in the direction of print-head travel.
These days I usually print on untextured matte / fine art papers with
an R3880. While output on semi-gloss/pearl papers can be extremely
good, this is where these printers truly shine (IMO).

I get outstanding results with my R2880 on Red River Papers,
particularly their Polar Pearl Metallic and Premuim Gloss PLUS. The
print resolution is set at 360dpi. Lightroom or Photoshop controlling
color with the appropriate paper/printer icc profile set.

My Epson R2880 is set as follows:
Media Type: "Ultra Premium Photo Luster" (that is the Red River
recommendation for Epson photo printers)
Color: 16-bit/channel
Color Settings: Off
Print Quality: SuperFine - 1440dpi

So to press the point, the file is sized with 360dpi and the
printer is
left to do its thing at 1440dpi.

The file is 360 PPI, and the printer's setting is 1440 DPI. Trust me
on this. I have corrected Adobe employees on this, but not for a
number of years.

I know, those are the numeric settings I use. Sometimes one can get
careless behind th keyboard. I should have said ppi when setting file
resolution & size. This whole issue can be confusing for those faced
with setting file resolution and printer settings when conflating ppi
& dpi for file size and print output. They serve different purposes.

So If I want a 12"x8" print, I will be looking at a file with ppi set at
360 (that is my default from RAW conversion, either with ACR or LR) and
the dimensions will be 4320 x 2880. That is the file which will be fed
to the R2880 which will churn away at SuperFine - 1440dpi. I could have
selected "SuperPhoto - 5760dpi" but that would be pointless and of
little benefit to the end result in 99% of cases

I wouldn't sweat it too much. With the earlier 13" printers
R1800/2400), they called the 5760dpi "RPM" mode. That was an acronym
for something. But I would use 2880dpi (not 1440) on gloss or
semi-gloss photo papers. There is a difference - and it's not costing
you anything (except time to print). If you want maximum resolution,
check/set print-head alignment reasonably frequently. Disable
bi-directional printing (which also improves alignment) - if you don't
mind waiting longer for the print.
If you're using ICC profiles, then they're made at a specific printer
DPI setting, and are usually named as such. A profile made for 2880dpi
will not be ideal if you print at 1440 dpi - the colours may be slightly
out. Using a microscope, I could see some difference using RPM mode,
but with a loupe, I couldn't.

About my experience, too. It seemed that 1440 would take a long time to
punch out a print of any size. And at normal viewing distance, not much
gained.

Alan Browne wrote:
On 2015-05-11 17:58, Me wrote:
On 12/05/2015 4:36 a.m., Floyd L. Davidson wrote:
Alan Browne wrote:
The numbers are those that apply after cropping and sizing the image.

So if you crop a 6000 x 4000 image down to 600 x 400
pixels (as an extreme example), then that's all the real
resolution left. At 150 dpi that would be 4 x 2.6
inches as a print.

That is a misconception. First, Epson printers print at
360 *PPI*. They cannot print at 150 *PPI*.


360 ppi is a divisor of the nominal printer dpi setting, 1440, 2880 etc.
I did some very thorough tests with an R1800 to assess resolution for
stereo imaging pairs, on glossy photo paper.
It did resolve more than 360ppi if the printer was sent an image (test
pattern) at precisely 720dpi and 1440dpi. Horizontal (relative to the
direction of paper feed) resolution of full-tones approached 360 lines
per inch. Diagonal and vertical resolution dropped significantly, as
did half-tones, but still easily exceeded 360dpi (180 lpi) overall.
Viewed under a microscope, the ink droplets on the surface are oval -
"stretched" in the direction of print-head travel.
These days I usually print on untextured matte / fine art papers with an
R3880. While output on semi-gloss/pearl papers can be extremely good,
this is where these printers truly shine (IMO).

Floyd's confused over what is in the edited image
(within, eg, Photoshop) and what is physically printed
on the machine per the print spec.

Not true. The Epson commercial grade photo printers all
print at 360 PPI. The consumer grade printers that are
also meant for office work (text) can print at 720 PPI.

The discussion was about an Epson 3880. But regardless
of the Epson printer, 360 PPI is correct for printing
photographs.

If one has an image that (like in my example) is 600 x
400 and one desires a 4 x 2.66" print, then specifying
it as 150 dpi will result in that nice little print.

What you are doing is telling the print driver that you want
the image resized to be 4x2.66 at 360 PPI. The printer doesn't
run at 150 PPI. The print driver will resample the image,
and sent the physical printer a 1440x95 image.

The specific problem as far as quality goes is that a
resampled image needs to be resharpened, and you have
not opportunity to do that if the print driver is allowed
to resample the input image.

Best method is to manually resample the image to the
actual print size in pixel dimensions, add appropriate
sharpening, and send that file to the printer driver.

Floyd can't get that between the editing s/w and the
printer there are the drivers that interpolate as
required (and using some pretty sophisticated s/w at
that) to fill the nominal 360 dpi space with ink
droplets spit out at (in reality) 1440 dpi x 720 dpi
(IIRC).

You don't appear to have read what I said. The fact is
that the Epson 3880 prints a 360 PPI, period. The print driver,
if you are willing to settle for that, will resample the
input image to the appropriate pixel dimensions. It will not
print at 150 PPI.

--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska)

Alan Browne wrote:
On 2015-05-11 18:22, Savageduck wrote:
On 2015-05-11 21:58:42 +0000, Me said:

On 12/05/2015 4:36 a.m., Floyd L. Davidson wrote:
Alan Browne wrote:
The numbers are those that apply after cropping and sizing the image.

So if you crop a 6000 x 4000 image down to 600 x 400
pixels (as an extreme example), then that's all the real
resolution left. At 150 dpi that would be 4 x 2.6
inches as a print.

That is a misconception. First, Epson printers print at
360 *PPI*. They cannot print at 150 *PPI*.


360 ppi is a divisor of the nominal printer dpi setting, 1440, 2880 etc.
I did some very thorough tests with an R1800 to assess resolution for
stereo imaging pairs, on glossy photo paper.
It did resolve more than 360ppi if the printer was sent an image (test
pattern) at precisely 720dpi and 1440dpi. Horizontal (relative to the
direction of paper feed) resolution of full-tones approached 360 lines
per inch. Diagonal and vertical resolution dropped significantly, as
did half-tones, but still easily exceeded 360dpi (180 lpi) overall.
Viewed under a microscope, the ink droplets on the surface are oval -
"stretched" in the direction of print-head travel.
These days I usually print on untextured matte / fine art papers with
an R3880. While output on semi-gloss/pearl papers can be extremely
good, this is where these printers truly shine (IMO).

I get outstanding results with my R2880 on Red River Papers,
particularly their Polar Pearl Metallic and Premuim Gloss PLUS. The
print resolution is set at 360dpi. Lightroom or Photoshop controlling
color with the appropriate paper/printer icc profile set.

My Epson R2880 is set as follows:
Media Type: "Ultra Premium Photo Luster" (that is the Red River
recommendation for Epson photo printers)
Color: 16-bit/channel
Color Settings: Off
Print Quality: SuperFine - 1440dpi

So to press the point, the file is sized with 360dpi and the printer is
left to do its thing at 1440dpi.

That's not what Floyd missed, however. I too set up my
prints at 360 (generally), but in the exaggerated case
(to reply to Peter's question) I set it at 150. The
driver's will interpolate and send the actual job at
1440 x 720.

You are both confusing the nozzle DPI rating with the
date input 360 PPI rate.

The printer has a 1440x720 dot rate, for each individual
ink dot from various in nozzles. That is a multiple of
the data input Pixels Per Inch rate.

You don't size the input image in relation to the nozzle
dot rate. It is resized in relation to the PPI rate,
which is 360 PPI. That is done on a per image basis.

You can essentially set once and then ignore the printer
resolution in DPI, though print speed and quality are a
function of how it is set. 1440x1440 is probably
what you actually should use, as 720 DPI is nearly a
draft mode resolution. For the highest quality it should
be 2880 DPI, but that takes more time than it is worth.

--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska)

On 2015-05-12 05:12:32 +0000, John McWilliams said:

On 5/11/15 PDT 9:38 PM, Eric Stevens wrote:
On Mon, 11 May 2015 17:33:04 -0700, John McWilliams
wrote:
On 5/11/15 PDT 10:30 AM, nospam wrote:
In article , Floyd L. Davidson
wrote:

So if you crop a 6000 x 4000 image down to 600 x 400
pixels (as an extreme example), then that's all the real
resolution left. At 150 dpi that would be 4 x 2.6
inches as a print.

That is a misconception. First, Epson printers print at
360 *PPI*. They cannot print at 150 *PPI*.

if you send it a 150 ppi image, they will.

Floyd has never fully understood the difference between ppi and dpi. I
doubt he ever will.

Epson printers- and there are many- may be able to print at any number
of *DPI*s. Mine does.

What printer do you have?

Epson 3800.

Input, expressed in pixels, not dots, can have a huge range of *PPI*s. A
fairly standard number of PPI's is 300-360. Sometimes the printer is set
to a DPI of the same number, thus confusing some.

What software are you using to set the DPI? Is it the printer driver
or something else?

Only the printer can set the DPI, at least that's the only way I know of.

You should be able to set the dpi via the printer driver dialog. I set
it that way with my R2880.

--
Regards,

Savageduck

On 2015-05-12 05:17:46 +0000, John McWilliams said:

On 5/11/15 PDT 9:20 PM, Me wrote:
On 12/05/2015 1:20 p.m., Savageduck wrote:
On 2015-05-12 01:05:44 +0000, Savageduck said:
On 2015-05-12 00:35:42 +0000, John McWilliams said:
On 5/11/15 PDT 3:22 PM, Savageduck wrote:
On 2015-05-11 21:58:42 +0000, Me said:
On 12/05/2015 4:36 a.m., Floyd L. Davidson wrote:
Alan Browne wrote:
The numbers are those that apply after cropping and sizing the
image.

So if you crop a 6000 x 4000 image down to 600 x 400
pixels (as an extreme example), then that's all the real
resolution left. At 150 dpi that would be 4 x 2.6
inches as a print.

That is a misconception. First, Epson printers print at
360 *PPI*. They cannot print at 150 *PPI*.

360 ppi is a divisor of the nominal printer dpi setting, 1440, 2880
etc.
I did some very thorough tests with an R1800 to assess resolution for
stereo imaging pairs, on glossy photo paper.
It did resolve more than 360ppi if the printer was sent an image
(test pattern) at precisely 720dpi and 1440dpi. Horizontal (relative to
the direction of paper feed) resolution of full-tones approached 360
lines per inch. Diagonal and vertical resolution dropped significantly, as
did half-tones, but still easily exceeded 360dpi (180 lpi) overall.
Viewed under a microscope, the ink droplets on the surface are oval -
"stretched" in the direction of print-head travel.
These days I usually print on untextured matte / fine art papers with
an R3880. While output on semi-gloss/pearl papers can be extremely
good, this is where these printers truly shine (IMO).

I get outstanding results with my R2880 on Red River Papers,
particularly their Polar Pearl Metallic and Premuim Gloss PLUS. The
print resolution is set at 360dpi. Lightroom or Photoshop controlling
color with the appropriate paper/printer icc profile set.

My Epson R2880 is set as follows:
Media Type: "Ultra Premium Photo Luster" (that is the Red River
recommendation for Epson photo printers)
Color: 16-bit/channel
Color Settings: Off
Print Quality: SuperFine - 1440dpi

So to press the point, the file is sized with 360dpi and the
printer is
left to do its thing at 1440dpi.

The file is 360 PPI, and the printer's setting is 1440 DPI. Trust me
on this. I have corrected Adobe employees on this, but not for a
number of years.

I know, those are the numeric settings I use. Sometimes one can get
careless behind th keyboard. I should have said ppi when setting file
resolution & size. This whole issue can be confusing for those faced
with setting file resolution and printer settings when conflating ppi
& dpi for file size and print output. They serve different purposes.

So If I want a 12"x8" print, I will be looking at a file with ppi set at
360 (that is my default from RAW conversion, either with ACR or LR) and
the dimensions will be 4320 x 2880. That is the file which will be fed
to the R2880 which will churn away at SuperFine - 1440dpi. I could have
selected "SuperPhoto - 5760dpi" but that would be pointless and of
little benefit to the end result in 99% of cases

I wouldn't sweat it too much. With the earlier 13" printers
R1800/2400), they called the 5760dpi "RPM" mode. That was an acronym
for something. But I would use 2880dpi (not 1440) on gloss or
semi-gloss photo papers. There is a difference - and it's not costing
you anything (except time to print). If you want maximum resolution,
check/set print-head alignment reasonably frequently. Disable
bi-directional printing (which also improves alignment) - if you don't
mind waiting longer for the print.
If you're using ICC profiles, then they're made at a specific printer
DPI setting, and are usually named as such. A profile made for 2880dpi
will not be ideal if you print at 1440 dpi - the colours may be slightly
out. Using a microscope, I could see some difference using RPM mode,
but with a loupe, I couldn't.

About my experience, too. It seemed that 1440 would take a long time to
punch out a print of any size. And at normal viewing distance, not much
gained.

Since I am not running a high turnover print production mill, even
without invoking the highspeed mode, producing 13" x 19" prints @ 1440
on the R2880 hasn't seemed particularly slow to me.

--
Regards,

Savageduck

John McWilliams wrote:
On 5/11/15 PDT 10:30 AM, nospam wrote:
In article , Floyd L. Davidson
wrote:

So if you crop a 6000 x 4000 image down to 600 x 400
pixels (as an extreme example), then that's all the real
resolution left. At 150 dpi that would be 4 x 2.6
inches as a print.

That is a misconception. First, Epson printers print at
360 *PPI*. They cannot print at 150 *PPI*.

if you send it a 150 ppi image, they will.


Floyd has never fully understood the difference between
ppi and dpi. I doubt he ever will.

What I actually do not understand is why this confuses
you so much.

Epson printers- and there are many- may be able to print
at any number of *DPI*s. Mine does.

It does not. Whatever printer it is, get yourself a
copy of the Service Manual and read it. Better yet,
because Epson manuals are not the best, get Service
manuals for several printers. Some information is in
this one, some is in that one, and you'll need it all to
get a good grasp of how it works.

Input, expressed in pixels, not dots, can have a huge
range of *PPI*s. A fairly standard number of PPI's is
300-360. Sometimes the printer is set to a DPI of the
same number, thus confusing some.

The printer resolutions listed in DPI are the nozzle dot
rate, fixed by the step rate at which the print head
moves and the distance between individual nozzles.

The physical printer PPI resolutions are for input data,
and are a function of the size of the dot matrix used to
generate a pixel.

All of these values, both PPI and DPI, are hardware
rates for how much the printer head or the paper
transport system moves.

None of them are continuously variable, and with Epson
the base rate for the finest pitch is 360 pixels per
inch.

--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska)