Judy,
One of the reasons I miss living in Phoenix Arizona was that I got much
better printing results using the sun. I did try to keep my printing
between 10:00 am and 2:00 pm and aimed directly at the sun for the most
consistent results. The times did not vary too much throughout the
year. [A possibility for more accurate timing would be a compensating
enlarger timer. Mine produces audible clicks. However it would be
preferable to have a digital readout since counting for several minutes
can be frustrating.]
You are correct in that one does not get the control and repeatability
without some additional equipment (at additional cost). However, I
prefer the sun as a light source because of the results. I have found
nothing to compare with the columnated light of the sun. Of course in
Arizona there is little water in the air, which I am sure makes the
exposure easier.
In Tampa Florida, I use a self-built light box, except for large prints
(over two feet). The biggest advantage is that I can print at all
hours. Using the sun in Tampa in a real challenge. I make a small test
exposure, then immediately precede with the working exposure. However,
sometimes even this is not quick enough to avoid changing conditions. I
do miss the results of the dry Arizona sun.
I have printed in Andover MA, Phoenix AZ, Philadelphia PA, and Tampa
FL. I've had the best satisfaction from prints made in Phoenix (sun
only). Second best location was Andover (sun only), then Philadelphia
(sun & light box) . I have had the most difficulties with printing in
Tampa (light box & sometimes sun). I can't help suspect the humidity.
(The humidity increases as my satisfaction decreases for these four
locations.
I would recommend that any student experiment with direct columnated
(sun) and diffused/dispersed light (under a tree or in a light box)
sources.
Jeff