Metz Flash Telecomputer Inaccurate

[breakaway]

Hi everyone. I just bought a new Metz 20BC6 flash. The flash seems to

have no way of controlling the flash output manually and according to

instructions, everytime I set my ISO to 200, I am to set my aperture

at f/8. I know the relationship between the f stops and shutter. So

when I try to half the f stops and shorten the shutter speed, my

images are always overexposed. I realise that even at f/8, my images

seem a little overexposed. This leads me to conclude that the

telecomputer is not so smart after all.

 

I then proceed to mount the diffuser and insert 2 pieces of blank

paper in between to reduce the flash and it works! Now it's accurate

but my question is, would it harm the flash in the long run by

inserting the paper there?

 

Anyone met with a similar problem?

[todd peach seattle, washi]

<i>"So when I try to half the f stops and shorten the shutter speed, my images are always overexposed. "</i>

<p>

Flash exposure doesn't work that way. The shutter speed is irrelavent to the flash exposure, as long as you're within the camera's sync speed range. You can vary the shutter speed to adjust the *ambient* exposure while using flash, but it won't alter the amount of flash exposure.

[beno_t_marchal]

<p>I second Todd. The flash burst is too brief for the shutter speed to have any impact on

flash exposure.

<p>With flash you deal with a dual exposure: the flash itself which you control using the

aperture and the flash output and the ambiant light which you control through the

aperture and the shutter speed.

<p>--ben

[lex_jenkins]

Regarding the use of materials directly on the flash to reduce the output, yes, it can potentially cause damage if the flash is used repeatedly in a single session without letting it cool. Flash units can heat up with repeated, prolonged use.

 

Even with color correction filters or other attachments authorized by the manufacturer I'll try to check my flash for overheating more often than I would when the flash is used without any filters or attachments.