Which lens for boarding shoots?

What do I need for good boarding shots of riders taken from the boat? Will a 200mm lens (300mm "film equivalent" on my DSLR) be enough to get good close-ups, or do I need a longer focal length?

Will a 300mm lens (450mm "equivalent") be significantly better? BTW, it's a 10 meg camera, so I think I have some room for enlarging and cropping for prints.

depends on how close you wanna get but i would say a 300mm lens would be way to close from the boat. I use my 70-200 from the boat mainly with a FF sensor.

70-200 is the norm. I'm usually at about 135mm with mine on a 1.6.

Thanks for the help, guys. I'm really new to this.

I'm guessing "FF" means a full frame sensor, which is equivalent in dimensions to 35mm film? So, does a 200mm lens have the same magnification on a FF DSLR as it would on a 35mm film camera?

At any rate, it sounds like a 55-200mm lens on a D40x (effectively ~ 82-300mm) will have the reach I need for the shots I want.

Thanks again.

So, does a 200mm lens have the same magnification on a FF DSLR as it would on a 35mm film camera?

Yes, a full frame sensor gives the same FOV as 35mm film. What gives you what you call additional magnification is really just increased pixel density that's inherent to most smaller size sensors. A 200mm lens provides a FOV that is the same on both FF and cropped sensors, what you're seeing is the higher pixel density on the crop sensor expanding to fill the same image plane as the full frame sensor, there is no actual magnification. This is important to realize if you like to crop a lot as you'll be using the 55-100mm range of that lens a lot with a 1.5X sensor.

Rich, thanks for the explanation. I can't remember the last time I was on a learning curve this steep, but now I understand what FOV is, and I have some sense of its significance. This has helped me better understand things I've read elsewhere.