This is just strictly my own opinion here, but to me the first shot looks like the properly exposed shot. I believe the issue here is that you have a rather high contrast between the lovely silky white of the water fall, which in my mind is your central subject, and the dark shadows, especially in the foreground. In such a case the question is "What should I expose for?". If you expose for the scene as a whole here you would blow out the water fall really badly and since that's the central point of interest, obviously you wouldn't want to do that.
If this was shot in RAW I might go back and reprocess and open up the shadows just a bit as there's little or no detail in the blacks (such as the rocks in the top left corner there) but I wouldn't really change the over-all exposure per say.
Now as far as your prints coming back a bit dark, I would like to add here that that could simply be a matter of the profiles or something that your processing place uses. This was a problem I ran into myself for quite a while...either my colors would be off or the shot would look too dark or too bright, etc.. It's worth asking your "lab" about...what color profiles they use and then (try to) use the same profiles, if available, on your own system at home so that what you see on your monitor (assuming it's properly calibrated) will be what you see in your prints.
It's also worth noting that many people (especially here on POTN) seem to recommend using the Adobe RGB color profiles because they have a "wider color range" (gaumet?) but the problem is that most processing labs don't use this profile at all...at least none that I've ever ran into. When push comes to shove, I usually set -everything-...camera, monitor, printer, etc., to sRGB so that there's a better consistency from device to device. There's also a fair chance at least that your lab is using sRGB as well unless they're using something proprietary.
It's also worth mentioning that if you're doing your own processing at home (which I assume you are since you're asking the question) to make sure you tell the lab NOT to do any additional processing! Many, if not most labs are set up to process your average yo-yo's snap shots (as that's usually the majority of their business). Remember your average camera user doesn't usually know much, if anything, about photography let alone the finer aspects of exposure, color correction, etc.. They "point and shoot"...literally...and most folks are usually happy if the picture doesn't come out totally blurred! LOL!!! As such the equipment the lab uses often makes automatic adjustments to things such as brightness, contrast, saturation, etc., based on "average" shooting conditions. If your images are already adjusted however, the "additional automatic adjustments" that are often done without the aid of a lab tech, will usually ruin your pictures.
Okies...just my thoughts!
Jim
"It is horrifying that we have to fight our own government to save the environment. " - Ansel Adams
Walczak Photography - www.walczakphoto.izfree.com
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