Developing Digital Prints

[Jetton]

I am very new to digital photography so any information on this will be appreciated.

How do digital prints compare with traditional film? Is the quality different, does it fade, what are the differences in the paper, what dimensions do the photos have to be to produce a good print, does dpi matter, what method you use to develop your photos, etc..?

And another thing is, I have photos of the same dimension, ie: 1600x1200, but with different dpis. Does the dpi actually mean anything in this case and will it make a difference in the print? I am questioning this due the the fact that if I deselect "Resample Image" in Photoshop, and arbitrarily adjust the w/h/res, the image stays constant while the dpi is heightened.

What about the comparison between a size 2560x1920 photo with 72dpi, and 1600x1200 with 180dpi? Which image is of higher quality?

Sorry about the bombardment of questions. Any and all information will be greatly appreciated.

Thanks a whole bunch,
J

[Jesper]

I can't say much about different kinds of paper and printing techiques, but a lot of that is described in the book Mastering Digital Printing (http://www.amazon.com/exec/obidos/tg/detail/-/1929685653/qid=1093005040/sr=1-4/ref=sr_1_4/102-8377346-9177718?v=glance&s=books).

The DPI number is not an actual property of the image itself. The only thing that matters is the number of pixels in the image.

The DPI number only matters when you are printing your image. If you deselect "resample image", Photoshop is only assigning a different DPI number to the image, but doesn't do anything to the image data itself.

If you print a 2560 x 1920 photo at 72dpi, the print will be 2560/72 = 35.5 by 1920/72 = 26.7 inches.

If you print a 1600 x 1200 photo at 180dpi, the print will be 1600/180 = 8.9 by 1200/180 = 6.7 inches.

Generally, for smaller prints, you need at least 150dpi for a print that looks good, and 300dpi for an excellent print. You won't notice much difference if you go higher than 300dpi.

Note that for larger prints, you can get away with less dots per inch, because you'll normally not be looking at those prints from very close up.

See also Display, Printing, DPI and PPI (http://www.photo.net/learn/resize/).