I would appreciate some assistance please. I have never scanned before, and want to get the most information from some old 3" x 2" family pics so I can work with them and enlarge them.
The problem I have is getting my head around the dpi vs ppi thing which I thought I had a grasp of...but obviously don't.
I presume that when I scan something I am creating a digital file, ...the equivalent of a file from RAW to say a TIFF. In the scanner setting options it says "resolution" which is measured from increments from 50 to 12800 dpi. (couldn't get the full screen shot, but the increments go right up 720, 1200, 2400, 3200, 4800, 9600 etc to 12800,
Click to view attachment
When I process a RAW file, the option for the resolution is in ppi. I usually use 360ppi as I use an Epson 9800.
Click to view attachment
Then after processing it into a Tiff, when browsing through bridge, when putting the curser over the image it says 360dpi. I thought in the Raw conversion is asked for pixels per inch - ppi?
Click to view attachment
Now to the other scanning confusion I have. Is the scanning programme asking for the output printing resolution in dpi??? ..because the numbers go to so huge.?
Click to view attachment Epson perfection 4870
I don't know which number to use to get the best quality information to work with to enlarge these small family photos.
Any clarification and advice would be most welcome.
Julie
Full Version: Scanner settings
You have justification being confused, because manufacturers of scanners, printers and software for them (even Photoshop has confused its share of users) do not (at least did not) adhere to a strict, or even sensible, convention on *pi. PPI can only mean pixels per inch, while dpi can be dots per inch or droplets per inch. PPI or DPI applied to an existing digital image is only a label telling the printer how to print the image a 600x1200 pixel image with a 300 ppi tag means "print at 2 inches by 4 inches, while the very same image file with a 72 PPI tag would be saying to the printer " make me 8.3" by 16.6"
When you are scanning, technically (at least unambiguous) is "samples per inch". Epson is using dpi as dots per inch. They are asking you to choose how many pixels to create for each inch of original artwork or photos in your case in the output scan file. ( Be aware that the scanner has a "physical limit" to its capabilities and it is usually way less than the specs for the product say. The higher and higher numbers are just the scanner offering to take the raw scan data and interpolate them for you. This scanner may say it'll scan at 4800 "dpi" but most folks will say it is not worth scanning much above perhaps 1600 "dpi", around its real physical limit!) If they are good quality prints, you might want to scan at up to 600 "dpi" (there's probably not much more detail in them that would warrant going higher).
So if you have a 3" x 2" photo setting the resolution of the scanner to 600 will give you a file of 1800 x 1200 pixels. This will resemble a digital image from a 2.2 MP camera. If you want to make significant enlargements from this 3x2 old photo, you could scan at higher resolution, say 1200 "dpi" and learn some post-processing tricks to "enhance/restore" them but don't expect to go much bigger than the original. If you had the negatives, however, you could scan them at even higher resolution and expect to be able to make bigger enlargements - the limiting factor in your case right now is the quality of the positive print.
Hope that gets you started
Andy
When you are scanning, technically (at least unambiguous) is "samples per inch". Epson is using dpi as dots per inch. They are asking you to choose how many pixels to create for each inch of original artwork or photos in your case in the output scan file. ( Be aware that the scanner has a "physical limit" to its capabilities and it is usually way less than the specs for the product say. The higher and higher numbers are just the scanner offering to take the raw scan data and interpolate them for you. This scanner may say it'll scan at 4800 "dpi" but most folks will say it is not worth scanning much above perhaps 1600 "dpi", around its real physical limit!) If they are good quality prints, you might want to scan at up to 600 "dpi" (there's probably not much more detail in them that would warrant going higher).
So if you have a 3" x 2" photo setting the resolution of the scanner to 600 will give you a file of 1800 x 1200 pixels. This will resemble a digital image from a 2.2 MP camera. If you want to make significant enlargements from this 3x2 old photo, you could scan at higher resolution, say 1200 "dpi" and learn some post-processing tricks to "enhance/restore" them but don't expect to go much bigger than the original. If you had the negatives, however, you could scan them at even higher resolution and expect to be able to make bigger enlargements - the limiting factor in your case right now is the quality of the positive print.
Hope that gets you started
Andy
QUOTE (AJSJones @ Feb 28 2008, 10:43 AM)
You have justification being confused, because manufacturers of scanners, printers and software for them (even Photoshop has confused its share of users) do not (at least did not) adhere to a strict, or even sensible, convention on *pi. PPI can only mean pixels per inch, while dpi can be dots per inch or droplets per inch. PPI or DPI applied to an existing digital image is only a label telling the printer how to print the image a 600x1200 pixel image with a 300 ppi tag means "print at 2 inches by 4 inches, while the very same image file with a 72 PPI tag would be saying to the printer " make me 8.3" by 16.6"
When you are scanning, technically (at least unambiguous) is "samples per inch". Epson is using dpi as dots per inch. They are asking you to choose how many pixels to create for each inch of original artwork or photos in your case in the output scan file. ( Be aware that the scanner has a "physical limit" to its capabilities and it is usually way less than the specs for the product say. The higher and higher numbers are just the scanner offering to take the raw scan data and interpolate them for you. This scanner may say it'll scan at 4800 "dpi" but most folks will say it is not worth scanning much above perhaps 1600 "dpi", around its real physical limit!) If they are good quality prints, you might want to scan at up to 600 "dpi" (there's probably not much more detail in them that would warrant going higher).
So if you have a 3" x 2" photo setting the resolution of the scanner to 600 will give you a file of 1800 x 1200 pixels. This will resemble a digital image from a 2.2 MP camera. If you want to make significant enlargements from this 3x2 old photo, you could scan at higher resolution, say 1200 "dpi" and learn some post-processing tricks to "enhance/restore" them but don't expect to go much bigger than the original. If you had the negatives, however, you could scan them at even higher resolution and expect to be able to make bigger enlargements - the limiting factor in your case right now is the quality of the positive print.
Hope that gets you started
Andy
When you are scanning, technically (at least unambiguous) is "samples per inch". Epson is using dpi as dots per inch. They are asking you to choose how many pixels to create for each inch of original artwork or photos in your case in the output scan file. ( Be aware that the scanner has a "physical limit" to its capabilities and it is usually way less than the specs for the product say. The higher and higher numbers are just the scanner offering to take the raw scan data and interpolate them for you. This scanner may say it'll scan at 4800 "dpi" but most folks will say it is not worth scanning much above perhaps 1600 "dpi", around its real physical limit!) If they are good quality prints, you might want to scan at up to 600 "dpi" (there's probably not much more detail in them that would warrant going higher).
So if you have a 3" x 2" photo setting the resolution of the scanner to 600 will give you a file of 1800 x 1200 pixels. This will resemble a digital image from a 2.2 MP camera. If you want to make significant enlargements from this 3x2 old photo, you could scan at higher resolution, say 1200 "dpi" and learn some post-processing tricks to "enhance/restore" them but don't expect to go much bigger than the original. If you had the negatives, however, you could scan them at even higher resolution and expect to be able to make bigger enlargements - the limiting factor in your case right now is the quality of the positive print.
Hope that gets you started
Andy
Thanks Andy, It would be good if they could all work out some consistent nomenclature, so folks like me had a clear platform upon which to learn. When professionals , software and books incorrectly interchange terms....gee it makes it confusing!
I am on my way now and will take your advice on scanning settings. Thanks for your time in explaining.
Julie
Wayne Fulton has a great free tutorial site at www.scantips.com from which new scanner users can learn a great deal. He walks you through all of the basics.
Doug
Doug
QUOTE (Doug Fisher @ Feb 29 2008, 12:31 AM)
Wayne Fulton has a great free tutorial site at www.scantips.com from which new scanner users can learn a great deal. He walks you through all of the basics.
Doug
Doug
Thanks Doug. Will go there right now.
Julie
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