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Re: Camera
Tesla List wrote:
>
> Original Poster: ARSONIST01-at-aol-dot-com
>
> Hi All w/ camera advice
> my dad has an old Minolta camera..(dunoo anything about it except
> that it has a big lens(like about 6-7" long). Now can i use this camera to
> take Coil pics if i keep it far away?(like 15'?) will that protect it and all
> electronics?
> second question is that on the shutter button, there is a dial w/ A,
> a ton of numbers, and a B. Now is this how i set the Shutter time? if so, how
> do i do it?
> thanks,
> alan
Alan,
Depends on how big your coil is--I'm sure that at 15 feet with some
coils, you would be 5 feet in front of the grounding rod. Camera
electronics would be the last thing on your mind (evil grin)
No, seriously, If it is all metal, you should be ok. The numbers you
mention are indeed your shutter speed, in fractions of a second (500 is
really 1/500 second) Each setting lets in double the light as the
previous one, from 1/1000 to 1 second. A is for auto, meaning your
camera probably has an aperture priority mode, where it sets the speed
for you. B is for Bulb (now an anachronism, for flashbulb) which allows
the shutter to stay open for as long as you hold the button down. There
should be some sort of meter visible in the viewfinder, which will
indicate a + or - reading, or shutter speeds if you are on "a". To take
correctly exposed pictures manually, you will need to set both the
shutter speed and aperture.
Have I lost you yet? hang on a sec, it's not as bad as it sounds...
Aperture is the ring of numbers on your lens: 2.8 4 5.6 8 11 16 22
etc. in F-stops. These close a diaphram in the lens by degrees, each
doubles the amount of light, just like the shutter speeds. The lower
numbers let in MORE light, not less...
So to control light, you must reach an agreeable combination of speed
and aperture. your meter should show you what is right, by either moving
a needle between plus and minus signs or some similar arrangement.
Coil pics are somewhat different, as the best ones are usually long
exposures. here is a simple test to determine exposures:
Get some color negative film, 400 speed is preferable to shoot dimly lit
subjects.
Set your camera's film speed or ASA dial to 400 (not your shutter
speed).
Run your coil in an environment where the sparks appear brighter than
the surroundings (ie. dark). Set your camera on a tripod, set your lens
to the lowest aperture number (most light) and set your shutter speed to
B. Using a watch with a second hand, press the shutter button gently
and hold for four seconds. A cable release would be best here, but a
light touch is ok if you are careful not to move the camera AT ALL.
Advance the film, move the aperture over one stop (higher number, less
light) and shoot another frame. Write the aperture numbers on cards, and
as you shoot each frame, place the cards in frame for reference. Go
until you reach the end of the scale. If you want, you could do another
pass at 15 seconds, and one at 1/2 second (using the "2" setting on your
shutter speed dial) Write down your settings, and send the film in as
normal. You should then get pics back of varying quality; use the
numbers to find the best combination, and you should be able to repeat
with the same settings every time.
Good luck,
Wells