What I want is for the image to be rendered full width with black fill at the top and bottom. It might be possible to arrange this in lightroom using the print module and borders, but I am going to try to do it with Photoshop.
This tutorial aims to do it using layers and the crop tool. No doubt there are dozens of ways a person could do this using photoshop, but this will at least get us started.I launch Photoshop CC. The first step is to find and open my image. I had lightroom export it to P:/images/unversity.jpg I use File -- Open and it is easy enough to navigate to the right place and open the image.
I make sure the "photography workspace" is selected (it is), now I am ready to try the steps suggested in the above tutorial.
Indeed the image is a background layer, and I need to convert it to a normal layer, otherwise photoshop will insist that the background layer is the lowest in a layer stack, which makes sense. This is as easy as clicking on the little lock icon on the right side of the background layer. It is now called Layer 0.
Now I select the crop tool and begin dragging the crop borders. The crop tool nicely shows me the pixel dimensions as I make adjustments. At the top (the options bar) on the left is a place to select the aspect ratio. I change this from 3x2 to 16x9 and voila! I get 3840 by 2160 with the crop set to the full width of my image. I click on the checkmark at the left side of the option bar when I am finished. This does not do what I want because the "content aware" box in the options bar was checked. Photoshop did some magic to fill the extra space with image rather than leaving it transparent. It takes only seconds to delete this result and redo things without the content aware fill selected.
Now to add a black layer under the image. At the bottom of the layers panel is a split circle (adjustment layer). I click this, select "solid color" and make sure it is black. When I click "OK" the black layer hides the image (which makes sense) It is simple enough to drag that layer below rather than above my image and now I see what I want.
Now, how do we save this? I use File -- Export as -- JPEG This brings up a file navigation dialog and I go to P:/images and save it as university2.jpg
All done, and I got exactly the result I wanted. It would be easy to select a color other than black. The tutorial shows how to add a drop shadow (which I don't want, but might be interesting someday).
Tom's Digital Photography Info / tom@mmto.org