[LargeFormat] Light meter recommendations

[Jim Hemenway]

Damn Richard... I knew I shouldn't have parted with that PR-1 (my first
lightmeter) for the Weston V back in 1962, or thereabouts.

But thanks, I'll look around for one at the next photo swap meet (PHSNE)
next month.

I don't know if I've ever seen diffraction... from what you posted, is
it then a blurred image all over the groundglass at smaller than optimum
f stops?  Earlier today I was making some more test shots, (paper
negatives) with the APO-Ronar CL 420mm.  These were shot at f64 and
halfway between f90 and f128.  Except for the OOF areas, I didn't see
any blurring on the groundglass.  I'm finding that this lens has lots of
coverage for the 11x14 but the corners are blurry, (not just soft) until
I go down to at least f64.  It's a process lens and I now understand
that the blurry corners are expected at normal rather than at 1:1 focal
lengths.

It is a great lens for 8x10!

-- 
Jim - http://www.hemenway.com



Richard Knoppow wrote:
<snip>
> > >
>   Find a working General Electric PR-1. The stop scale goes
> from f/1 to f/128
>   To check the cell of any Selenium meter measure a light
> level which can be read on both the high and low range. On
> the GE you can get near the ends of the meter scale. The
> indicated exposure should be within a fraction of a stop.
> When selenium cells go bad they compress the upper readings
> so will read low for bright light.
>   My Luna Pro goes only to f/90.
>   I have only one lens calibrated to f/90, a very old Bausch
> & Lomb Series V extra wide angle Protar (f/18 wide open). At
> f/90 the diffraction blur is quite evident on the ground
> glass.
>