
Jim N. answered 07/07/19
Patient, knowledgeable photography tutor
One way to expedite this workflow a bit: after exporting the JPG and deleting the DNG file, drag the new JPG onto the LR icon, which will automatically bring up the import window with the JPG located (that way you won't have to navigate through directories).
What camera are you using that creates 500mb files? I have a very high-res Sony A7RIII that makes 50mb files. Hard drives are so cheap now; you can get a 4TB drive for $90, so you might want to consider whether it's worth the time to save a bit of space by converting to JPG. With LR, as you probably know, you can have files on your computer's internal drive as well as external drives.