Ed, will you be trying again this winter? I was researching this topic before going up to Modesto a few weeks ago to see Valley Uprising. I knew it would be the wrong conditions anyway, and it was probably the haziest day ever! I'm thinking about trying again in December although I'm trying to think of other things to do in the area because it's a long shot up from SoCal for a slim chance of sighting Half Dome!
one of my practical realizations was that you want to be further away from Half Dome because of the Earth's curvature and the intervening foot hills.
The more dramatic shots will be taken from the western side of the Central Valley, like my first image of the Feb 2013 campaign
this is 89 miles away, and on the plane of the central valley floor, so you're looking through a lot of atmosphere.
It would be good to have a clear atmosphere index... unfortunately the "visibility" index that airports report isn't useful... turns out to have a distance limit that is much shorter than the 100 miles, or so, of atmosphere we look through.
It's also possible that adding red filters, as was done in the Lick pano, might help cut down the light scatter, notice that the haze is "blue"
Getting up in the hills is a definite possibility. I have no doubt that we'll eventually get a fantastic image of Half Dome from the Valley... the conditions have to be just right... unfortunately, you'd like to get this in the early morning on a cold clear day (windless) so the atmosphere is very settled. But the illumination of Half Dome would be less than ideal.
Another possibility is to get a look after the passage of a storm with clearing at sunset.
If you want the Moon too, it's making it even harder...
The reason airport visibility sensors are of limited utility is they are not concerned with looking UP through and out of the bathtub atmosphere of the Valley. They are concerned with runway range visibility and (low) cloud ceiling, down init.
Keep on snapping!
I know its not the valley floor but why not from somewhere on the crest of the Diablo range?
As Ed notes immediately after a winter storm would be best. I can't think
of any index other than smog particulate reports that would help. And, as
noted, airport RVR's are only concerned with horizontal visibility below
decision height (200') and they only care that you can see an object like,
say, a 737 rather than Honnold standing naked on Thank God Ledge.
DMT's idea of getting a little above the really yukky stuff is gud.
The problem with 'immediately after' a winter storm, is well, it depends and the dependencies are against the would-be photog.
Winter storms bring moisture. The calm after the storm is the perfect breeding ground for fog.
I think you need one of those really windy days out of the north immediately after the storm (like a low pressure located over eastern Nevada or Utah) , sweeping down the valley and blowing the muck clear out (yuk yuk).
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