[Assistant]

As a "converter" from the photography side to the "dark side" CGI still have some problems with the idea of DPI and Image size.

Now when Im working on a project i have a big texture about 4kx4k that I need to get it good becouse of all the detail in it. But now when im going to render this all out in 4500x4500 what dpi is best for the texture?

300dpi is good for printing but dose my material need to be 300dpi or is it enough with 74dpi?

thanks

[kami]

The pixel resoultion of an image can be defined by its image size and dpi resoltion. So I assume you already know, what pixel resolution you need for your final output. (if you know how much dpi you need for the print and at what size you want to print)
Your textures should always be in a reasonable proportion to this final output resolution. This depends on whether the texture is seen only in the background or if you see just a small part of that texture in the foreground, strongly enlarged. Since the render engine doesn't care at all about dpi, all that matters is the width and height of your texture in pixels.

[Mihai]

A 4500x4500 texture at 300dpi is the same size as a 4500x4500 texture at 74dpi. As kami wrote it doesn't matter when viewing the image on screen, it's just the amount of pixels in it that matters. DPI only matters if you want to print it and then make sure it has enough pixels to print properly at a given DPI and print size.

[Assistant]

For the final print i need 300 dpi but i just got unserten if the detail for the Texture would differ if i used 74 or 300 dpi. If not I will go for 74 instead. smaller file size.

[kami]

smaller file size.

you will notice, that the file size will be exactly the same, if you only change the dpi value in photoshop, without resizing the image.
remember: as long as the image is not printed: it's quality and size is determined ONLY by its pixel values (eg. 3000 x 2000 px)