Commercial print resolution about 5 megapixels?

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.

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. 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).

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.

--
Regards,

Savageduck

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.

On 5/11/15 PDT 12:28 PM, PeterN wrote:
On 5/11/2015 11:35 AM, John McWilliams wrote:
On 5/11/15 PDT 8:12 AM, Alan Browne wrote:
On 2015-05-11 10:30, PeterN wrote:
On 5/11/2015 9:26 AM, Alan Browne wrote:
On 2015-05-11 02:40, RichA wrote:
I got a 16x20" print made and measured the smallest detail visible
which was about 1/5th of a mm. This works out to about 5 megapixels
represented by the print. Is this the limit of standard print
resolution?

Depends what "Commercial" means.

Magazine print runs at a resolution approximating 180 dpi as does
poster
work (advertising). (Can't compare directly as the dot pattern is not
at all the same).

The Fujifilm Frontier that many stores used as their "lab" printer
printed at 720 or optionally 1440.

"Pro" printers such as the Epson 3800 physically print at 1440, but
the
typical preparation resolution is 360.

I frequently do extreme cropping, and print 12x18 at 350 ppi. Would I
gain anyting if I prep at a much higher ppi?

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.

Would I gain anyting if I send a tiff file over? (Costco accepts tiff
files)

Not really. A good JPG (usually) has enough detail and DR for any
printer. This assumes of course that it's a decently prepared image.
(Decently exposed and sharp to begin with too).

Many folks conflate PPI with DPI, but they most definitely are not the
same.

Printers often have a range of dots they can put down (DPI), and the
higher number, the better resolution of the print. Input, however, is
critical, and the input is pixels. One can print a 48 ppi at a dpi of
1400, but the results will be horrid, a waste of ink and time. One can
print a 600 ppi at 150 dpi, but also a waste, as a much better print can
be made with a higher dpi setting on the printer.

As to the original question, ask the printer what it was printed at. You
may get a blank stare, but worth asking. As to TIFF, you may get better
results, more due to the printer thinking you know a lot! Probably more
important to match the color space- so ask if they want sRGB or aRGB.

Please let us know how the next one turns out.

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.

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.

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.

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.

On 5/11/15 PDT 2:11 PM, Eric Stevens wrote:
On Mon, 11 May 2015 10:30:51 -0400, PeterN
wrote:

On 5/11/2015 9:26 AM, Alan Browne wrote:
On 2015-05-11 02:40, RichA wrote:
I got a 16x20" print made and measured the smallest detail visible
which was about 1/5th of a mm. This works out to about 5 megapixels
represented by the print. Is this the limit of standard print
resolution?

Depends what "Commercial" means.

Magazine print runs at a resolution approximating 180 dpi as does poster
work (advertising). (Can't compare directly as the dot pattern is not
at all the same).

The Fujifilm Frontier that many stores used as their "lab" printer
printed at 720 or optionally 1440.

"Pro" printers such as the Epson 3800 physically print at 1440, but the
typical preparation resolution is 360.

I frequently do extreme cropping, and print 12x18 at 350 ppi. Would I
gain anyting if I prep at a much higher ppi?

Would I gain anyting if I send a tiff file over? (Costco accepts tiff files)

You would gain if you prepped your print at 100% at the native
resolution of your printer (360 dpi for Epson, 300 dpi for just about
everything else). That way the printer driver has to do no resizing or
resampling of the image. That way you print what you had seen.

That's an old saw, true for some printers, makes no difference on
others. However, depending on the printer driver's capabilities, more
pixels *may* make a better print, even if the DPIs of the printer is
fixed @ 360 or set thereto.

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.

--
Regards,

Savageduck

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

--
Regards,

Savageduck

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.
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. Remember I have 36 mpix to work with.

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


--
PeterN