Scott, all AF systems will have problems focussing on an even, bright, white surface. Simply because it lacks contrast. If you're doing prefocus, you can do it manually. If you need to use AF on the fly, then I don't quite understand why you want to focus on the snow... I would have thought that you could focus on the skier, which would stand out pretty nicely from the snow from a contrast POV.
That said, my experience with AF on the *istD is that it works in a different way than do earlier Pentax cameras. I don't know the MZ-5n, but I do know the Z-1, MZ-S and 645nII. The latter has the same AF logic as the MZ-5n, I think. The AF in *istD typically use a little more time to get started focussing than do the predecessors. OTOH, it hunts less in difficult AF situations, so in total, I find that it use less time to achieve focus. Note, however, that this applies only when I've pre-selected an AF point on *istD. For some reason, the AF usually screws up completely if set to automatic selection of focus point. Especially with lenses of less than f/4 open aperture. On a sidenote, I find the *istD to handle extremely poorly with gloves on. The buttons are either too small or not sufficiently protruding. Another problem which I think applies to all digicams, is that it's practically impossible to do any chimping (okay, instant review) because the LCD drains a _lot_ of battery when operated at temperatures below zero. Apart from the LCD, though, I'm positively surprised about how well the camera works in the cold. It endures a lot more than my bare fingers...:-) Cheers, Jostein ----- Original Message ----- From: "Scott Nelson" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Saturday, November 20, 2004 7:46 AM Subject: *ist D AF and snow? > I shoot a MZ-5n right now, but the AF has trouble with snow. I like to > shoot backcountry skiing, so you can see how this is a problem for me. > I was wondering how the *ist D AF handles this sort of thing. Does > anyone have experience they'd like to share? > > > Thanks, > > -Scott >
