Photo scahhing size

[larry brubeck]

I recently recieved some old family photos from my sister, She scaned them and then burnt them to a cd,When I open them in photoshop,image size is huge, like 40 in+40 in, was wondering did her scanner do this, Not familure with scanner out put.I have no problem viewing them, but printing them is impossible at that size, have to change size of each one. thanks

[Mac McDougald]

Takes seconds to change each one and resave.

Or make an action and run it on all of them at once.

Mac

[Patty Clarke]

Larry,

Since I'm travelling the road of understanding resolution, I'm curious about the quality of those "huge images",
how do they look on your monitor? (Yes, I know that screen res is different than print---but it's still good info for me.)

When you downsize and print, how is the quality? I'm learning a lot about resolution via this site:

<http://www.scantips.com>

I'm learning that different equipment and scanning resolution varies, so I'd be curious about the quality of your sister's files and what method she used to produce them....

Patty

[Colin Walls]

Larry:
What resolution did you set the scanner to?
What does PS say the image size/resolution is? [Right-click on image title bar.]

Chances are the number of pixels you've got is fine, just the resolution setting too low. So If you tried printing "straight", it would be too big. If you used Print Preview and scaled, you'd be fine.

It would be better to get the size right though. Give me the numbers I asked for above and I can comment further.

[dave milbut]

use image> image size and uncheck the resample box. change the resolution to your printer's or something that'll get you a decent print... at least 300ppi.

[Colin Walls]

Dave:

Sorry to be critical, but, although your advice is basically sound, the words "change the resolution to your printer's" are, at best misleading. This is where all the PPI/DPI confusion comes from. A printer doesn't have a resolution, it has a dot pitch. AIn't the same thing.

However, having had my rant, the 300PPI value is reasonable, but, depending on the image, values as low as 150PPI can be just fine. With a normal inkjet, values >400PPI seem rarely beneficial [and could actualy degrade the image.

[dave milbut]

right. k. i didn't mean crank it up to 1440... :) besides, a "1440 dpi" printer is misleading. the term refers to the combined output of all heads. for example if it's a 4 head printer rated by the manufacturer as producing output at 1440dpi, the effective resolution for each head is 360dpi. If it's a 3 head printer it's 480dpi. THAT's the number I was referring to when I said set to maximum printer resolution. Take the printers maximum rated resolution and devide by the # of print heads to get the printer's maximum.

But... (or Milbut if you prefer <g>): dot pitch is a monitor term:

"dot pitch <http://www.webopedia.com/TERM/d/dot_pitch.html>"
Also called phosphor pitch, a measurement that indicates the diagonal distance between like-colored phosphor dots on a display screen. Measured in millimeters, the dot pitch is one of the principal characteristics that determines the quality of display monitors. The lower the number, the crisper the image. The dot pitch of color monitors for personal computers ranges from about 0.15 mm to 0.30 mm

printers do have a dpi. dots per inch, but mine doesn't, it's continuous tone. it's SCREENS that don't have DPI, they have PPI. scanners are also "rated" in dpi, but might be more accurately described in spi (samples per inch) <http://www.computer-2tr.com/Tips/03/20030321.html>

my printer has a rated (equivilant) dpi of 306. that IS the stat. it's not a "dot pitch". it's continuous tone dye sub (olympus p330n <http://www.olympusamerica.com/cpg_section/cpg_product.asp?more_info_lobby=1&p=19&bc=23&produ ct=227>)

True photographic output with continuous-tone, 306 dpi dye-sublimation
printing in 24-bit color






PPI (webopedia)





Short for pixels per inch, a measurement of how a monitor displays an
image. The resolution of an image displayed on a monitor is determined
by its ppi, or the number of pixels contained within one square inch of
monitor space.





DPI (webopedia)





Abbreviation of dots per inch, which indicates the resolution of images.
The more dots per inch, the higher the resolution. A common resolution
for laser printers is 600 dots per inch. This means 600 dots across and
600 dots down, so there are 360,000 dots per square inch.




and again (from computer2tr.com):

SPI (samples per inch) is scanner and digital image resolution. To scan
an image the scanner takes a sampling of portions of the image. The more
samples it takes per inch, the closer the scan is to the original image.
The higher the resolution, the higher the SPI will be.





PPI (pixels per inch) is the number of pixels displayed in an image. A
digital image is composed of samples that your screen displays in pixels.
(Pixels, or picture elements, are the dots on the screen.) The PPI is
the display resolution not the image resolution. (Adobe Photoshop uses
PPI and Corel Photo-Paint uses DPI for image resolution so it's no wonder
everyone is confused.)





DPI (dots per inch) is a measure of the resolution of a printer. It properly
refers to the dots of ink or toner used by an image setter, laser printer,
or other printing device to print your text and graphics. In general,
the more dots, the better and sharper the image. DPI is printer resolution.





LPI (lines per inch) refers to the way printers reproduce images, simulating
continuous tone images by printing lines of halftone spots. The number
of lines per inch is the LPI, sometimes also called line frequency. You
can think of LPI as the halftone resolution.




<http://www.computer-2tr.com/Tips/03/20030321.html>

<http://www.webopedia.com>

(from computer-2tr.com):

In practice, SPI and PPI are often used interchangeably. DPI is frequently used in place of one or both terms. However, even if you call it DPI, remember that each dot or "unit of measure" behaves differently depending on whether it is a scanner (or scanned image), a monitor (or on-screen image), or a printer (or printed image).

(emphesis, mine)

dave

[larry brubeck]

The pictures are 72 dpi, quality is good. as well as the the picture that was scanned.Changing size for print doesnt loose quality.Does the scanner dpi setting change size or quality of a picture. I am using a old Canon6000 printer, but size is limited to paper size.

[barry gray]

Wow Dave-
You may not be able to comprehend what a billion is, but you sure got the dpi/ppi/spi nailed.
Nice!

[dave milbut]

larry, if you res up to say 400ppi, unchecking the sample box, the picture will appear much smaller when printed without losing any quality. you may need to crop to get it to fit on the page. if it STILL doesn't fit and you don't want to crop, up the resolution again (with resample unchecked) until it fits.

You may not be able to comprehend what a billion is,




is my lack of coffee one morning going to be held against me forever? :)

besides, as i quoted in the lounge, jp getty said "If you can count your money, you don't have a billion dollars."

but you sure got the dpi/ppi/spi nailed.




I've been involved in a few of the ppi/dpi wars here so I've learned from the pros. Not through any real effort on my part. More osmosis. <G>

[Colin Walls]

Sorry Dave. I apologise if I was sounding like I was saying you didn't know what you were talking about. I know that not to be the case from reading your frequent and helpful postings. I was only concerned that your turn of phrase could have been misleading.

I think the PPI/DPI/resolution thing has an odd emotional effect. Most people start of confused, often getting the wrong idea. Later, when it all becomes clear, it seems hard not be be upset by apparent misunderstanding of confusion.

The Getty quote sounds like the Rolls Royce salesman: when asked the price, he said "if you need to ask, you can't afford it".

[dave milbut]

I apologise if I was sounding like I was saying you didn't know what you
were talking about.




no need colin. you're very helpful too. I was just clearing some things up. It started small, just clearing up the dot pitch thing, then just steam rolled (i.e. "well, i've gone this far, might as well put in the whole enchalada!") don't ever be afraid to be-otch slap me when I need it! :)

(and I often don't know what I'm talking about. I just fake it most of the time! <G>)

[Colin Walls]

Dave:

I'm in Marketing. I know all about sounding like you know what you're talking about! :-))

[LenHewitt]

Dave,

>>I just fake it most of the time! <<

Learnt that from your wife, I assume....<g>

[YrbkMgr]

HA!

Touché Len!