I've learned to ask myself "will I really really want to spend hours printing this image?" as I look through the camera. 90% of the time, I put the lens cap back on and move along.
But, I have gotten to where I know what I want an image to "say" I suppose, and I can tell through the VF if it seems like I can get it there in the darkroom. (I'm a lith printer and lately been getting into masking, so one print can take quite some time - days even, to dial in. That's just my thing, very happy with it, YMMV of course).
My last road trip, I street-viewed some of the route and found some things to check out. Shot very few frames, and my print backlog right now is maybe 6-7 images, including stuff I've test printed and put aside to think about.
Yes. I was out with my camera today and I had just one subject in mind. I wanted to take some photographs of a tower. I took about 20 shots, fully knowing that I would only want to print 1 or 2 (assuming they are acceptable). I was out for about an hour in a town but I didn't think anything else was interesting enough to bother with.
