I've had a few people ask how I put together the image collages in my blog posts. I create them in the Adobe Lightroom Print Module. Here are the steps I use to do this.
UPDATE: My friend Laura Shoe just posted on her blog with a chapter from her video training series that goes into more detail about the Print Module.
First, create a collection of the images that you want to place in the collage. This can be a Quick Collection or a regular collection. Go to that collection in the Library mode.
Next, switch over to the Print module. You will see the images in your collection at the bottom of the page. Over in the Layout Style menu on the right side select Custom Package.
I set the File Resolution to 125 ppi (I find 125 an easy number to work with as you will see later when setting the custom file dimensions)
Print Sharpening is set to Standard/Glossy (I actually haven't tried any other settings, feel free to experiment)
JPG quality set to 80
Now comes the math part. Don't worry, it is easy math that even I can do. This is where the File Resolution set to 125 comes into play. The range for PPI is 72 to 1200. I want my image for the blog to be 500 pixels wide, so I set the custom file dimensions to 4.00 in x 12.00 in. 4x125 = 500 pixels. I selected 4 inches because my files are 2:3 and I wouldn't have to resize two images set side-by-side. I told you the math part is easy. The tall dimension (12 in here) will change, depending on the content of the collage. It will usually end up being shorter, but this gives me room to spare while setting up the collage.
Now that the page is set up you can drag in images from the bottom of the page. Simply drag an image onto the layout and then drag it into place and then drag out a corner to size it appropriately. As the images from most dSLR cameras are 2x3 inches the horizontal images will need to be resized up to fill the width but tall images should come in without needing any adjustment (refer back to 4 inches by 125ppi). If your camera gives you files with a different aspect ratio or if you crop your images to other ratios than 2:3, you may need to adjust the file resolution and file dimensions to fit your images. A little bit of experimentation with numbers should get you there.
Things can get a bit tricky/hairy here. If the page is taller than you need you can adjust the tall dimension smaller, but if you go too small it will shift all the images on the page so they might overlap on each other. You can make the page taller again, but that won't fix the affected cells, you will have to go back and drag the image cells back to where you want them. It is better to have too much white space at the bottom than to make the page too short and have to re-do the layout. You can bring the JPG file into Photoshop and trim off the extra white space if necessary.
If you want to do a bit more calculating, you can figure out the exact height you need. Add up the heights of all the images on the page. In this case there are 4 at 2.667 inches and one at 3 inches. 4x2.667 = 10.668 + 3 = 13.668 inches, which you can type into the custom dimensions. Again, this is all based on using 2:3 aspect ratio images. Your mileage may vary if using other aspect ratios.
If you have an identity plate set up in Lightroom you can put it on the image as a watermark.
Here I have selected a PNG image and set the size and opacity. Uncheck Render on every image unless you want each cell to have the watermark. Simply drag the identity plate to where you want it to appear. You can also drag the corner handles to reset the scale (size) of the watermark.
Alternately, if you don't have an identity plate set up in Lightroom you can open the JPG in Photoshop after exporting/saving from Lightroom and add a watermark using your favorite method.
I set the color profile to sRGB for the web and use perceptual intent.
Once everything is in place you can click on the Print to File... button in the lower right corner and select where to save the file and give it a name. It will take a few seconds for Lightroom to render all the images to size and create the print job.
Here is the resulting image from the above settings...
Thanks, Mom, for letting me use my photos of you!