Today’s Question: Is there a way to adjust the export file sizes in Lightroom? I would like for them to be just a tad larger than what I’m currently getting.
Tim’s Quick Answer: You can most certainly specify pixel dimensions (image size) for photos you export from Lightroom, including creating an image that is larger than the pixel dimensions of the original capture. The options related to output size can be found in the Image Sizing section of the Export dialog.
More Detail: By default, when you use the Export feature in Lightroom to create a derivative image, that image will have the same pixel dimensions as the original capture you’re exporting. Obviously, in many cases you will want to change the pixel dimensions for that derivative image, such as for creating an image file for printing at a specific size.
If you turn on the “Resize to Fit” checkbox in the Image Sizing section of the Export dialog, you can specify the output dimensions you want to use. Note that in order to resize the image you are creating as part of this process, you need to have something other than “Original” or “DNG” selected from the Image Format popup in the File Settings Section of the Export dialog.
With the “Resize to Fit” checkbox turned on, you can then specify the output dimensions using the various options. The settings available allow you to choose from a variety of methods for describing the output size of the image being exported, the dimensions, and the unit of measure.
Note that there is a “Don’t Enlarge” checkbox that you can turn on if you want to make sure that the image you are exporting can’t be sized to dimensions that are larger than the original image. This will help ensure that, for example, you aren’t risking a reduction in image quality for lower-resolution source images. But if you leave that checkbox turned off you can specify dimensions that are larger than the original dimensions for the image you’re capturing, and the derivative image will then be sized based on the settings you have established.
I should add that here I’m referring to the overall pixel dimensions of the image file being created during the export process. The Quality setting also impacts the file size when you are creating a JPEG image from your source photo. That file size doesn’t relate directly to the potential output size for the derivative image, but rather to the overall quality. In other words, when it comes to producing derivative images for high-quality output I would focus on the actual pixel dimensions of the image, not on the file size (in megabytes, for example) of that image.