Need help - Sunak 383 Super flash and Canon 300D

[Guest]

Archived from groups: rec.photo.digital (More info?)

Greetings! I want to use a simple flash to photograph school football
game at night. I do not want any TTL or any fancy staff. Many cenuries
back I used to have a flash which measured the reflected flash
intensity and switched itself of when enough light reached it's sensor.
I think these type of flashes used to be called Auto Flashes.

Some one recommended Sunpak Auto 383 super flash. I have not used
this type of flash for a long time. I just want to make sure of one
fact before I order the Sunpak flash. Imagine I photographed a football
player at 40 feet with 5.6 and 1/160 sec and Sunpak flash. Now the
player comes close to 20 feet. Do I have to anything extra or the flash
will take care of the exposure automatically. With thanks.

 

[Guest]

Archived from groups: rec.photo.digital (More info?)

Autoflash (non-TTL) relies upon the amount of light bouncing back from
something to be sensed by the photosensor in the flash unit. So
athlete running from 40' to 20' will increase the amount of light
bouncing back, and the flash cuts off its output sooner. But keep in
mind that the single atlete on an open field reflects back less light
than a single individual in a room with ceiling and walls, so the flash
may output more light than it truly needs for a good exposure of the
athlete.
(I assume you are aware that you will need a very powerful unit and a
high ISO rating for your film/digital camera if you hope to shoot any
distance with the flash, because of the inverse square law of physics
about the drop in intensity of light with distance!)

 

[Guest]

Archived from groups: rec.photo.digital (More info?)

I looked up the Sunpak 383 and it has Guide Number 120 for ISO 100. If
you use ISO400 film/digicam setting, that is a GN=240. So if your lens
is used at f/4, your light can reach 60' and you'll get a good
exposure. Farther away, and it will be darker than you want. Keep in
mind that GN are calculated upon INDOORS with ceilings and walls, and
are often optimistically rated, so you are likely to find that even 60'
will be a bit of a reach and will be a bit dark.