Abril:
I shoot at HQ 2288x1712 It's fast, it holds enough for a dive and I think it looks good, But a friend (nikon loyalist) said it didn't look sharp enough. What's your thought? I have the oly C-4000z & generally like to print them at 8x10.
I have the same camera as you.
HQ = about 150 photos to a 128MB card.
SHQ = about 50 photos to a 128MB card.
They are both 2288 X 1712 but the SHQ has less compression than the HQ. It is therefore a larger file and should also be a better quality photo. That may come into play when you get a print made but I can't tell the difference between the two on my computer monitor.
I'll sometimes use SHQ when I do a 1 tank kayak dive here at home on Maui. I know I won't want more than 50 or so pics.
However, if on a trip where I am making a two tank boat dive I use the HQ setting so as to get the most photos out of a 128MB card. Even the 150 pics were not enough for 2 dives on my last trip. I took both my housings and both my cameras and changed housings between dives. You can always change out cards between dives.
The rule of using the highest quality setting on your camera doesn't necessarily apply in all instances due to its effect on how many pictures you can take. The TIFF setting on the C4000 will yield the best quality photo for a print. However, it is slow for the camera to process and you can only take about 11 photos on a 128MB card. That's fine on land for that "special" shot you want to print but not for underwater unless you are on a mission for only a few shots.
On the rare occasion that I got a few prints made from HQ or SHQ photos I adjusted the photo in Photoshop and cropped it to the size of the print I wanted and saved it as a TIFF. I then burned it onto a CD and took it to Costco for prints. The results were very good. You could do the same process with a home printer minus the CD burn but I am not a believer in home printers matching the quality of the professional equipment that Costco or other stores use. Besides, the 4X6 prints at Costco are under $.20 each.
The sharpness, or lack of, is the nature of the beast on that camera and probably a lot of other prosumer digital cameras. I adjust every photo with the "Unsharp Mask" in Photoshop. I found that the + and - sharpness control on the camera itself made no difference.