Back in my studio days, we had a bit more than 64,000 w/s in flash power and it wasn’t enough to light a car with one pop. Then I did some shooting at the Volvo Bus & Track Studio in Gothenburg where I wasn’t allowed to touch the lights because they had a guy whose job it was to light vehicles. I thought we had a lot of light until I went there and stood out on the cyc and popped my meter and WHOOMP! The Volvo soffboxes were on the ceiling and were 5x15 meters (32x65 feet) and at full power they were lighting buses with models and single popping at f16 for DOF. Nobody got burned, just blind. I have some of those shots kicking around still, so I’ll see if I can find them put them up somewhere on one of my sites. It’s hard to believe, but we shot trucks on location with 8x10 and cars with 4x5.
Currently I do not own a 500ws strobe and I can’t recall that I ever did. So you think my math is wrong? Doesn’t 2 + 2 still equal 5?
Jan
On Oct 19, 2013, at 10:55 AM, Santa Fe Imaging wrote:
Jan you are too funny!... This
doesn't need calculus... Your math is very dubious. It's like
that joke about the three guys who buy a car and get short
changed. (what happened to the other ten bucks?)
Or you must work with a 500 ws flash unit from hell. I remember
shooting cars with 4000ws packs and having to multi-pop them...
according to your arithmetic, there must have been something
radically wrong with those Elinchrom packs.
THINK JAN! a 500ws strobe isn't that powerful....
1. a grey card up on a wall and spot meter in hand
2. a 500W tungsten light 10 feet away covering 100 sq feet of
wall.
3. take a reading at 1 second...and get say f/16
4. replace the Lowell light with a strobe... same distance and
same coverage Use flash meter to get reading... (shutter speed
is obviously irrelevant) you'll get close to the same f/16.
4. replace the halogen lamp with a 500ws
2 a 500 10/19/2013 8:10 AM, Jan Faul wrote:
Did you do well in math? Can you explain how a 500 watt
tungsten bulb can deliver the same light as a 500ws flash
delivering light in 1/175th sec?
Take one second and divide by 175 = and multiply the result
by a big enough number to equal 500. Got it? That’s how many
tungsten watts equal a 500 ws studio strobe.
On Oct 19, 2013, at 10:00 AM, Santa Fe Imaging wrote:
There are all kinds of mechanical and
electronic considerations that come into play but it
seems to me that a 500 watt tungsten lamp exposed for 1
second should give the same amount of light to the
sensor/film as a single 500ws flash exposure.
On 10/19/2013 7:34 AM, Andrew
Davidhazy wrote:
I think that something vexing is the fact that the electronic flash delivers its light over a short time while tungsten lamps can (or do) deliver it over a long time. If one compares them at the assumed duration of the flash then the tungsten bulb will come out the weaker of the two by far. But if you compare them during an exposure time of a second or a minute or more then the tungsten lamp wins. It seems to me anyway.
Andy from Rochester
Art Faul
The
Artist Formerly Known as Prints
------
Camera
Works - The Washington Post
.
Art Faul
The Artist Formerly Known as Prints ------ Camera Works - The Washington Post
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