Hi there, S.t.

I'm surprised that you had to use such a high ISO to achieve this in full sunlight.

I just got a Hoya R72 filter today. Though it was heavily overcast (and probably about three stops lower in light levels) than the shot you took, I was able to achieve the following settings with the Mark II:
ISO 200; f/8.0; 15 seconds

http://photos.ulyssesphotography.com/photos/7311196-O.jpg



I do get the same glow in the center 20% area of the shot, and I'm going to try to research decent and less painful methods of dealing with that. This first effort doesn't have a lot of pop to it, but I attribute that at least partly to my inexperience (absolute first attempt) plus the very cloudy sky producing low contrast and possibly scattering/diffusing the IR effect.

Here's another effort at trying to deal with the center glowing area, and an attempt to get some more detail out of this hit white cloudy sky. :-)

http://photos.ulyssesphotography.com/photos/7318768-L.jpg



But I'm very encouraged, much more so than I expected to be. :-)



Spendthrift wrote:
>
> Yes, the exposure was at four seconds, however, it was also shot at
> iso 1600....iso 100 would have been 64 seconds at f9, which I shot
> it at.

--
Ulysses
www.ulyssesphotography.com