Nature photographer goes tamed

Hello all-
As a nature photography enthusiast I have friends who see my photos and ask if I could please shoot their family portrait. After all how much different could it be ? Well, up until now I've gracefully declined these requests; birds and bees, after all, don't gripe if their wings don't turn out just perfect . Anyway, I gave in and shot these with my 50mm f 1.4 and they seem pretty soft to me. I know the trend may be for portraits to be a little softer than what I am used to in nature photography, but these guys want to enlarge one of these up to 20x24 and I just can't see it holding up to that. I'm going to ask for a "redo". Any suggestions as to how I can get these sharper next time out. Anyone have a max they use as far as ISO. It was shady but not dark with the sun filtering through. How about aperture? I varied it but didn't see a big difference. I started out with a tripod but soon dismounted it. I did try a few with flash (580 EXII) but wasn't happy with that.

what were your settings on these? the first one looks sharp to me.. the rest look like you either missed focus or you had too slow a shutter speed.

I'll leave the technical critique up to those with more knowledge than I have. I'll just say that for a first time move into portraits, the overall effect of these is great. The autumn colors - landscape & family - work beautifully together. Maybe you should expand your horizons more often.

Thanks. I'm not sure what happened to my EXIF data on these. I think when I switched over to Mozilla something happened The ISO was 200 on all but the last which was at 320, aperture f/8 and shutter speed 1/25 which may be the problem. I hand held these and might just have to go back to the tripod and/or open it up a little more.

No1 is without doubt the best. I would advise a smaller print maybe 13 * 19 max as even on a 8mp camera there''s still enough pixel density.

the 2nd one everyone looks relaxed and not so tense. Its just ashame it doesnt look that sharp.....