I was thinking of making some prints of my fractals. Many sites say that you should print at 200-300 DPI (dots-per-inch). But at 72 or 96 DPI, it looks great on my computer. How much different will it be when I print it? 300 DPI seems like overkill.
Ann is correct - 300dpi there or there abouts is the standard printing resolution. This is about the resolution you need to stand up to close scrutiny. Images that don’t need that kind of scrutiny such as billboard or screen printing do go down to as low as 72dpi but originally start off at full resolution and are increased in size by using dimensional scaling or 'dimming' i.e. you increase the physical area of the image by reducing the resolution and retaining the optical effect (at a distance) of hi res imagery. Don’t make the mistake of creating images or photos at anything over 300dpi - there will be no discernible increase in printed quality. Scanners that advertised huge interpolated resolutions are for the most part gimmicks and you would only need to scan things in the thousands of dpi if it were line work instead of tone work. the only possible reason for scanning an image at resolutions higher than 300 dpi were if you had an original with fine mesh or grille detailing that may form moiré or jaggies at lower resolutions.
A computer screen only displays at a fraction of the resolution than that of printed material but sometimes optically appears sharper. The easiest way for you to see the difference is get your self a 300 dpi image - dupe it and reduce the copied files resolution to screen res and print them side by side for comparison.
Thanks for the info.
Now I just need a program to change the DPI, not resample it. I cannot seem to get it to work in Irfan View. Also, do you think if I printed a fractal flame at around 150-200 DPI, I would get poor results?
Have you tried The Gimp.. I.m not sure if it will or not.. I usually change it in my printing program... I have that option with my HP all in one.. I know it will in photoshop..
also ... you need to calculate pixel resolution based on 300 DPI when you render ...
so .. for example if you want an 8x10 print render at 2400x3000 ... or even more .. then scale or crop the "true" image out of your render
I've been rendering and working at 3200x2400 .. but would like to work bigger someday ... but it's hard working at such large resolutions because you're always working in some form of reduced view
Bear in mind the difference between dots per inch (dpi) and pixels per inch (ppi). There's a lot of confusion about it, and the terms are often used incorrectly - people tend to say dpi when they mean pixels per inch...
Dots per inch is a property of some printers (e.g. ink jet). Anything under 300 dpi can produce a noticeably grainy picture - "draft" printing is often lo-res like this, but "best" or "photo" printing should give you 300 dpi.
Pixels per inch is a property of your image and the final print size. If your image is 1600x1200 pixels and you want an 8" x 6" print this will give you 200 pixels per inch. This is a perfectly adequate resolution, and provided it's printed at 300 dpi will look fine. 150 ppi is probably the lowest you'll get away with if you're looking closely at your prints - I always try to keep to 200 ppi.