Image Scaling

[Ultima546]

In the tutorial it suggests to use .jpg files and have them sized at 214x308 px for all upright cards. I've done this by making a quickie in Photoshop for a card back, but when I place the file into my /setimages/general folder and run Lackey the card back gets resized and enlarges, ending up looking a bit fuzzy. What is the actual size that the program outputs my file to?

And, this is probably a fairly obvious question so forgive me for asking it (my last time using image editing software was a few years ago), but would it be better to create a larger size (res?) base file, then shrink it to the size that I need (in this case 214x308)? My understanding is that the quality of the image would not decrease in a smaller sizing, but would if I were to upscale it, assuming the aspect ratio remains constant. Am I correct in my understanding? Would that be the best way to do something like that?

Thanks for any helpful responses offered,
Ultima546