Metering for landscape photography with Velvia 50 ASA and Hasselblad/Mamiya RZ67?

[Helinophoto]

Just as an update;

I did a couple of trips this weekend to try things out.
I brought my newly acquired Mamiya RZ67 with me, along with a 50mm f4.5 (Mamiya??) lens.
This lens has 77mm filter threads, so the cokin-p fitted and screwed in nicely, no problems at all there =)

Now for the metering, I used both my Sekonic l-358 and the Sekonic l-208, which came in the bag when I bought the camera used.
I used the 40 degree lens on the 358, but still, with the sun in my face and all, short on time and kind of stressed, I actually ended up using my 1ds mk II's spot to get a few readings around the lighter areas of the scene, as well as measuring the mid tones to get an idea of the contrast.

Still, calculating 5 added stops, due to pola + nd-grads, was kind of tough there and then, so I bulb-exposed from 5 to 25 seconds (light was fading fast as well). Most shots were fine around 10-15 seconds at f16.
Going to take a look at a few of those meters that swhiser mentioned, because I simply don't trust a reflected 30-40 degree measurement, made with the sun directly in my face....thinking that the sunlight must somehow get scattered into the light metering sensor somehow, because they are so exposed...I don't know, a lot to learn i guess

Here's the sea-scape shot I am talking about:
http://www.apug.org/gallery1/showimage.php?i=63470

The next image, was measured using only the seconic l-208's 30 degree reflected meter. Here I simply just measured the scene in the middle of the photo and guestimated the sky-balance to be around 2-3 stops (At this pont, I am happy, as long as I get details in there, perfection comes later). Problem was that the meter varied 1-2 stops from measurement to measurement, so it seems like the sun "polluted" the readings a few times.
http://www.apug.org/gallery1/showimage.php?i=63469

I did shoot some Velvia frames from the sea-scape scene, will be putting it up later after I get it back from the lab and have finished scanning

Thanks for all the feedback so far =)

[markbarendt]

Another technique you may try with your L-358 is duplexing.

With the dome installed but retracted take two readings. One pointed directly at the light source the other pointed toward the camera. Average the two.

[polyglot]

Still, calculating 5 added stops, due to pola + nd-grads, was kind of tough there and then, so I bulb-exposed from 5 to 25 seconds (light was fading fast as well). Most shots were fine around 10-15 seconds at f16.

There's an easy way around the filter-factor compensation: you set the uncompensated exposure on the camera, then every click (except for 1/250-1/400... unlikely when using Velvia!) of the shutter speed wheel is one stop. If you go past 8s then the maths isn't much harder (1/4 minute, 1/2 minute, 1 minute, etc) except that reciprocity gets involved for most films so you use Acros or Provia for the really long shots and mostly avoid that problem.

The other thing is that when using an ND grad, I find it easiest to do the exposure calculations on part of the scene that's under the clear part of the filter. Say you have a reading for foreground and sky, the latter being 5 stops brighter. You whack on the 3-stop grad and the difference is now 2 stops so you decide to put the foreground at -1 and the sky+ND at +1. Meter the foreground with an exposure compensation of -1 (i.e. go 1 stop faster than metered) and dial in that exposure. Then if you have a CPL, put two more clicks on the speed dial and close down about 1/3 stop in aperture (for a total of 1.7-stop compensation on the CPL).