PRINT - Adobe Photoshop Lightroom 3: Streamlining Your Digital Photography Process - page 303

dramatically speed print time but, of course, produces lower quality output. With
Drat Mode enabled, the rest of the Print Job options become disabled. Use Drat
Mode Printing if you only need a very rough print of the photos. h is can be handy
sometimes, such as when you just need a quick contact sheet to compare comps.
Otherwise, for the best quality prints, leave Drat Mode Printing unchecked.

6

Print Resolution
When Print Resolution is checked, you can specify an output resolution in pixels
per inch (ppi). Regardless of their native resolutions, all the photos in the print job
will be resampled to the specii ed resolution as they are output from Lightroom.
Depending on the size and native resolutions of the photos you're printing and
their output sizes, this usually results in either upsampling or downsampling. During
upsampling, Lightroom interpolates the original image data to make new pixels for
the output. In downsampling, the reverse occurs: pixel data is discarded to match
the output to the specii ed resolution. h e maximum Print Resolution you can set in
Lightroom is 720 ppi; the minimum is 72 ppi.

As mentioned earlier, the importance of higher resolution determines the ability
to resolve more detail and make larger prints. h e resolution that an image can be
made to dif erent print sizes is based entirely on the requirements of the printing
medium, and the intended viewing distance determines the necessary resolution
for high-quality output. Depending entirely on the i nal size and the detail in the
original photo, it's safe to assume that most photos should be printed between 180
and 480 ppi.

For example, to reproduce high-quality photographs in a topic like this one, the
image i le must be somewhere around 300 ppi at i nal print size. A high quality
inkjet print most ot en requires resolution between 180 and 240 ppi at i nal print
size. A very large print, one that a viewer needs to stand several feet from to view,
can be printed at 180 ppi (or less) with good results. Huge, building-size billboards
can be successfully printed using i les of 100 ppi and less.

It's usually ok t o print multiple photos that have dif erent native resolutions all at
once, as long as they are all within the specii ed tolerance. However, this can be
impractical, and sometimes resampling is necessary to produce the best possible
quality. For example, if you're printing a group of photos that at their i nal print size
will have dif erent resolutions, you may want to resample all of them to the same
resolution so that the printed results appear similar.

Example A: A 10 x 10 inch i le at 100 ppi is the same as a 1 x 1 inch i le at 1000 ppi.