DPI print query
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Dimensions of image file in pixels / dimensions of print in inches = DPI (or more correctly PPI)
So if an image is 1800 x 1200 pixels and you print it 6 x 4 inches the DPI is 300, which is good. It's generally advised that if the DPI works out at 300 or more the quality of print will be good. But for large prints that are usually viewed from a greater distance you can allow it to drop.
So if an image is 1800 x 1200 pixels and you print it 6 x 4 inches the DPI is 300, which is good. It's generally advised that if the DPI works out at 300 or more the quality of print will be good. But for large prints that are usually viewed from a greater distance you can allow it to drop.
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So how do you calculate and find out the pixels on pic?
Can I have an example please?
I've cropped any shots on picasa to size 10 x 15 , what if I send them for print and dont have 300 ppi? they look ok on laptop, does that count for anything? Sorry for getting so basic
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Right-click on an image file and look at the dimensions under properties. That's the easiest way.
If you send an under-sized image it won't look as good. If you upload it to DSCL the system they use calculates DPI and gives you a simple quality rating for the chosen print size based on the image file you upload. You get this assessment before you place and confirm the print order.
Looking ok on a laptop doesn't ensure that the print will look ok necessarily. But for what it's worth, I do all my processing on a laptop at the moment and get excellent results with prints from DSCL.
Stick with the Basic (not Professional) options on DSCL, upload a couple of files and see how their system rates them for your chosen print size. In general, you'll only run into problems if:
If you send an under-sized image it won't look as good. If you upload it to DSCL the system they use calculates DPI and gives you a simple quality rating for the chosen print size based on the image file you upload. You get this assessment before you place and confirm the print order.
Looking ok on a laptop doesn't ensure that the print will look ok necessarily. But for what it's worth, I do all my processing on a laptop at the moment and get excellent results with prints from DSCL.
Stick with the Basic (not Professional) options on DSCL, upload a couple of files and see how their system rates them for your chosen print size. In general, you'll only run into problems if:
- You crop a lot to compensate for using a lens that's too short; and/or,
- You want to print really, really big prints - but for reference I get very good quality prints up to 18"x12" from DSCL from a 10MP sensor.
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The DPI or PPI (dots per inch or pixels/points per inch). The important thing to remember is that there isn't a ruler invented that can measure a digital file in inches.
1800 x 1200 pixel file, what's the biggest I can print it at 300 DPI/PPI?
1800 pixels / 300 pixels per inch = 6 inches
1200 pixels / 300 pixels per inch = 4 inches
So at the recommended 300 DPI/PPI I could happily send this file to be printed at 6"x4"
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OP
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One more question
What counts as a "large print"
Is 15x 10 classed as large?
Cheers again
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Anything that measures 15 x 10 elephant lengths is very large, whether that's trunk and tail extended or not.
KIPAX
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However its not that simple.. (ok its simple but it isn't) I have had pictures 640 pixels at the longest edge printed bigger than 6x4 (7x5 inch) and they look good enough to sell.. perfectly acceptable
I wouldnt like to see a newbie go away with the thought that a pic must be at least 1800 pixels wide to get a 6 inch print
I take my pictures on my Nikon D3000 at the highest resolution RAW and it produces pictures at 3872x2592 resolution. So going by this theory of printing at 300 dpi, I presume that the images can be printed at max 12x8 inches for assured quality. I realise that they may look nice when printed at larger size as well, but there is no guarantee they will. In order to (say) print 15x10 or larger, is there a way that I can get the camera to generate an image at a higher resolution, or is that limited by my D3000's 10.2 MPixels?
Also, if I crop it in Photoshop at 300dpi and at 15x10", will photoshop ensure that the additional pixels are filled in adequately to produce a (guaranteed) good print?
Also, if I crop it in Photoshop at 300dpi and at 15x10", will photoshop ensure that the additional pixels are filled in adequately to produce a (guaranteed) good print?
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That will happily print larger and you'll get results to be pleased with.
Larger prints are viewed from further away, you're easily capable of getting very good 18x12" prints from your 10MP sensor (I regularly use DSCL to print images from a sensor that size to those dimensions). When you get to poster-sized prints the DPI drops right down anyway, so take those same files and print very large if you want to.
Looking at any image from a distance of less than bout 3x the diagonal length is pixel-peeping your prints (some people will say 5x the diagonal).
Larger prints are viewed from further away, you're easily capable of getting very good 18x12" prints from your 10MP sensor (I regularly use DSCL to print images from a sensor that size to those dimensions). When you get to poster-sized prints the DPI drops right down anyway, so take those same files and print very large if you want to.
Looking at any image from a distance of less than bout 3x the diagonal length is pixel-peeping your prints (some people will say 5x the diagonal).
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Ok.. 10x15 what? numbers without units (inches, centimetres, miles) don't really have a large/small value in this context. 10x15 cm would be about 6"x4" which is a fairly normal size holiday snap about 1/4 A4-ish, 10"x15" isn't a standard print size I know of.
For normal "let's see what it looks like" and "pass around with granny" sized prints I'd go for 6"x4", for something to frame I'd go bigger (but I'd choose the frame first and print to fit).
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Oh, right
As I said above somewhere, its a crop size on picasa, I just assumed inches
It just says 10 x 15 large print in crop option
How come every day I learn stuff but seem to understand less? :bang:
Hope this helps explain my confusion