DPI vs PPI Photoshop and Lightroom and Bit Depth

Started 2 months ago | Discussions thread
mike earussi Veteran Member • Posts: 9,127
Re: DPI vs PPI Photoshop and Lightroom and Bit Depth

VectorSigma68 wrote:

So I've been really looking into optimizing my workflow to be able to get great prints and fantastic color detail in my photos. I've noticed that you can set your working space in Lightroom and Photoshop. I currently have these set to 300ppi. Can I go higher or does this produce a lower size finished image? What does this do in the digital realm in terms of detail to work with when editing?
I am also currently trying to learn more about bit-depth. I currently have all of my working spaces set to TIFF 16-bit ProPhotoRGB for exports and my working colorspace within lightroom and Photoshop.

Your settings of 16 bit tiff using the Pro Photo RGB color space are correct for best quality.

In PS/Lightroom the final size of your image is determined by the width and height settings. If "resample" is not selected then the ppi also determines print size, but if it is selected and left at 300ppi then PS will interpolate (i.e. add) new pixels if you increase the print size or subtract pixels if you decrease the print size.

For instance, for a 24mp file size of 4000x6000 ppi this will produce a native print size at 300ppi of 13.3"x20," but if you wanted to print that larger, say 20x30, but still maintain 300ppi you would select resample and PS would then make new pixels. PS can't actually create new information but it will  create new pixels by averaging the original pixel information to keep the print from looking pixelated.

You can also use other interpolation programs besides PS, such as Topaz Gigapixel, as they do a better job of creating those new pixels than PS so the enlarged print looks better.

Printer resolution is measured in dpi (dots per inch) not ppi which refers strictly to camera sensor resolution, with Canon using 300dpi as its base printing resolution and Epson using 360. This is different from ppi and they are easily and commonly confused with each other.

For best printer resolution the middle level selection (600dpi for Canon and 720dpi for Epson) usually produces the best results, with lower settings creating some pixelization and higher settings just taking longer to print and using more ink without producing a better looking print.

 mike earussi's gear list:mike earussi's gear list
Sigma SD1 Merrill Sigma 105mm F2.8 EX DG Macro Sigma 17-50mm F2.8 EX DC OS HSM Sigma APO Macro 180mm F2.8 EX DG OS HSM Sigma 70mm F2.8 DG Macro Art +1 more
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow