A few months ago I was asking around about solar chargers and after having done a lot of research and using one all summer, I thought I'd pass along what I learned to the places I first asked my questions.
I ended up choosing a Brunton Solaris 12 (no affiliation) and was very happy with it. This model of charger folds up to about 9" x 5 1/2." Unfolded it is about 30" x 18." Its output is 12 watts.
The panel alone weighs about 12 oz. With pouch and the adapter plug, it weighs about 14 oz.
I used this panel to charge my satellite phone and video camera batteries. I used my camera a lot but only used my phone for an average of a few minutes a day. I had no spare sat. phone battery, and one long life spare video camera battery. It was a very cloudy summer and I was on the move all day, but this panel still kept me in charged batteries. I just had to make sure I "made hay while the sun shone." Under normal conditions, it would have been very easy to keep these items charged up.
They claim it takes about 1-3 hours to charge up a digital camera or camcorder, and about 3 hours to charge up a satellite phone. That seems about right to me. I did find out that the quality of sun makes a very big difference. The brighter and higher the sun, the better it charged. No sun, no charging.
If you have a big, fixed camp, you'll probably want to consider a larger panel. For backpacking and sheep hunting and the like, this one is hard to beat.
I kept this panel inside a plastic pouch inside a pocket in my pack, and it held up great without any particular "babying."
On thing I didn't understand when first researching this topic is how the solar charger would actually hook up to my electronic devices. Basically, the charger comes with a female car jack (cigarette lighter) plug. For my satellite phone, I just plugged in with the male car jack plug. For my camcorder, I got a battery charger with a cord and male car jack plug.
Definitely consider the weight of the charger compared to the weight of extra batteries. The longer the trip the more sense a solar charger makes.