Yes, the file size of the Lightroom-converted file sounds about right. But, if I'm interpreting your comments correctly, why are you importing and then just converting to JPEG? What do you think you are accomplishing? The advantage of importing raw images is that you can use all of the Lightroom tools to take advantage of the additional flexibility you get when working with raw files. Then, you export JPEG images when you need them for any specific purpose such as e-mail, or to send to a commercial printer, or tw Io post on the web.