i still do NOT understand

[bluesmap]

in photoshop how do i change dpi without changing the size of the image? everytime i alter dpi the size increases

[Damo77]

Turn off the "Resample Image" tickbox.

[Damo77]

Wait, are you talking about file size, or physical dimensions?

[Damo77]

You're aware, aren't you, that resolution is completely irrelevant unless you're actually printing?

[bluesmap]

this is for printing actually.

[bluesmap]

ok i see how the resolution stays the same but the "document size" changes with dpi. that should be ok..


thanks

[eddarr]

First understand that it is pixels per inch rather than dots per inch. Dots per inch is a printing term and pixels per inch is the resolution of an image.

If you have an image that is at 300ppi and you change the dimensions it will be resampled to a new quantity of pixels because it will always divide the dimension by 300ppi.

It might help to state what it is you are trying to achieve.

[bluesmap]

printing an image at 8 x 10

should i leave my pixels/inch at default settings?


my printer says

books are printed at 300 DPI. The largest photos you can use - full page pictures in our 13x11 book - should be no bigger than 3900x3300 pixels. Placing images larger than this on a page in BookSmart will not improve the end product, as our printers print at 300 DPI. Larger images will simply make uploading more difficult, or even impossible, and may also result in scaling artifacts.

Please know that although 300 DPI is optimal, we can accept images down to 150 DPI. Know that at that size, your printed pictures may not look as great as you'd like.

im using an online printer and thats what they say on the FAQ section. so now im thinking i should just leave the PPI at default since its not dpi

jeez i never can understand this

[Damo77]

Honestly, don't complicate it. Just set your crop tool to 8,10,300 in the options bar and crop.

[gooble]

Originally Posted by bluesmap

printing an image at 8 x 10

should i leave my pixels/inch at default settings?


my printer says

im using an online printer and thats what they say on the FAQ section. so now im thinking i should just leave the PPI at default since its not dpi

jeez i never can understand this

I have recently gone on several rants in the forum due to the fact that people interchange dpi and ppi as if their equals and they're not.

I was reading information regarding printing size and getting conflicting information over and over. Even the pro lab where I get prints was interchanging them so it wouldn't surprise me in the least if this book publisher you're talking about is doing the same thing.

I think I have things understood now. Basically don't worry about dpi in the least unless comparing printers that you want to buy and/or use to tell which one has finer detail. Many inkjet printers have dpi in the thousands so if they're saying it's 300 that's a red flag right there that they're mixing things up.

Now, ppi really only has any meaning when choosing an output size for a print. I won't go into web viewing but I basically wouldn't worry about it in the least for computer and web viewing. Certain printers require a certain ppi for best image quality it may range from 300 to 760ppi. The lab I use wants 300ppi images and they do photographic prints which means, as far as I know that there are NO dots so dpi makes no sense.

What this means is, say you have a 3888x2592 pixel image that you want to print at 12x8 inches at 300ppi. You multiply the dimensions in inches by the ppi and get 3600x2400 pixels. That is actually less than you started with so in PS if you go to image resize and set ppi to 300 and document size in inches to 12x8 then it will resample the image to 3600x2400 pixels. If you wanted 15x10 inches then it would upsample to 4500x3000 to maintain 300ppi.

Hope this helps.

[Underscore]

I think you mean PPI, not DPI. Photoshop doesn't have anything to do with DPI. Your printer determines DPI based on the way the printhead is manufactured.

I see this error in denotation quite a bit and probably adds more to confusion vs solving problems and giving answers.

[poloman]

Here is a screen shot. Note cropping parameters at the top of the page. Note image size pop up. It is this easy.

[Mark1]

I just adjust the image size in the print driver, not in the image editor.

When I hit "print" a menu comes up and asks what size I want it to be printed at. I tell it and off it goes.

[poloman]

I do this so I can do an accurate sharpening as my last step.
I save my files in 2:3 ratio tiff format at full size with all edits except sizing and sharpening. This way I am ready to produce whatever size my client might want.

[Lowner]

I just adjust the image size in the print driver, not in the image editor.

When I hit "print" a menu comes up and asks what size I want it to be printed at. I tell it and off it goes.

So do I! Why make life more complicated than it has to be?