I used to just take a stab at what the mid-tone should be
If that worked why not stick with it ? I don't mean that in a sarcastic way.
I have three prefered methods of metering myself.
1, look for a nice fluffy white cloud meter off it and give +1.5 stops.
Thats a widely used rule of thumb for slide film I was trying to find where I had originally found that suggestion and could not find the original link but found the following thread on large format info a good read http://www.largeformatphotography.info/ ... sparencies
2, Take a stab at a mid tone reading in the abscence of the aformentioned white cloud, I usually go for a likely looking bit of tree bark say or a path.
3, And now for the heresy, wave your DSLR at it and extrapolate from what looks good on it if its a bit of a complex scence with no easy choice of midtone.
I know some members of this forum have a low regard for method three perhaps particularilly as Ken Rockwell recomends it.
There is an interesting disscusion I found on this to on Large Format info http://www.largeformatphotography.info/ ... ith-a-DSLR
As one often does I found Frank Petronio's comments entertaining but maybe thats just me.
By the way I don't have a spot meter but I spot meter in the most accurate way possible. http://www.johndesq.com/pinhole/booster.htm
I have a twisted sense of humour so I find this funny
http://www.rogerandfrances.com/subscrip ... ystem.html
Their more sensible take on the zone system
http://www.rogerandfrances.com/subscrip ... 0zone.html