Questions regarding digital vs. film macro settings

For the past 15+ years, I'd always shot an Ikelite-housed Nikon N90s, for the past 10 years with a pair of Ikelite 200 (pre-digital) strobes. I've finally gone digital and purchased an Ikelite housing for my Nikon D200 and a pair of Ikelite DS160 strobes for an upcoming trip back to Anilao.

With my film rig, 99% of my macro shooting was with a 60mm lens where I'd shoot the strobes on TTL, the camera on aperture-priority (the shutter on the N90s would sync at 1/60) and matrix metering and adjust the aperture according to the distance of the strobes to the subject. My primary subjects are small, slow-moving creatures such as nudibranchs, mantis shrimp, etc. where getting as close as I'd like to the subjects is rarely an issue. The vast majority of the time the exposure was correct unless the subject was white or black, in which case I'd adjust the EV accordingly.

A couple questions:

1. Is there a reason the vast majority of digital macro shooters seem to shoot at faster shutter speeds than 1/60 for the kinds of subjects I mentioned? It seems to me that shooting at 1/60 would allow smaller apertures and therefore more depth of field. Am I missing something?

2. Is there a good reason not to shoot the D200 on aperture-priority at ISO 200 using TTL and matrix metering? As I shot Velvia (ISO 50) typically at apertures of f16-f32 and almost never had issues of insufficient strobe power, it seems to me that insufficuent strobe power will be even less of an issue with the increased ISO. I realize that there are potential diffraction issues at very small apertures that didn't exist when shooting film, but that aside, is there a good reason why I shouldn't shoot my D200 with similar settings as I used with my N90s setup?

Thanks!

I normally shoot macro with shutter speed fixed at 1/250, the maximum on my Canon 20D. My reasoning is that most of the light will come from the strobes anyway and the amount of strobe light that reaches your sensor is independent of the shutter speed since the strobe burst duration is much shorter than 1/250, so you always capture anything. Longer exposures are needed when shooting scenes with a blue water background, but that does not include most of my macro photography.

Wrt to the second point, I often should in aperture priority at ISO 200, TTL and matrix metering. I just rarely go below F16 but I have never done any serious comparisons of different settings and I know some stop down further and trade of spatial resolution for dept of field.

Bart

I agree that shooting at 1/60 of a second will allow for greater DOF due to closing down the aperture. But it depends on the power of your strobes and their positioning. My strobes will allow me to shoot at f/32 and 1/250 of a second and still get a proper exposure. So since I am not limited by the amount of light, I don't think about what shutter speed I will use and instead focus more on aperture settings.

I used to shoot at f/22... and yes, it offered greater DOF... but at the cost of sharpness! Most lenses are most sharp around f/8 to f/11 (don't flame me for this if your lens isn't!). So to maximize my sharpness and DOF, I usually shoot around f/14 to f/16. Of course this knocks out ambient light quite a bit... if thats what you want!

But again, I always keep my shutter at 1/250 because I want to reduce any possibility of camera shake affecting a shot. The only times you would want to shoot at a slower speed is if you want more ambient light or want motion blur.

My 2 bits!

Thanks, guys. I appreciate your feedback!