----- Original Message -----
From: "Hans van Veluwen" <hcvanveluwen@xxxxxxxxx>
To: <olympus@xxxxxxxxxxxxxxx>
Sent: Saturday, March 24, 2001 2:57 AM
Subject: Re: Hama video converters [was: Re: [OM] Off-brand tele/wide
converters for iS?]
> : For 35mm you can refer to the rule - focal length/aperture must be smaller
> : than or equal to the front lens diameter, otherwise vignetting will occur.
>
> I see your point. The 3x converter I would want for the iS-3000 would need a
> 100mm front element, and become too huge and heavy.
Not to speak of a 4X converter. I doubt the Hama 4X converter has a front
element diameter of 130
mm. The longest off-brand converters for iS-3 / iS-3000 I've seen in
advertisements has been 400 mm.
They would then be 2.2X converters and need to have at least 72 mm front
elements. Maybe this is
about the longest focal length which would still be a practical combo.
Thanks C.H. and Hans!
Regards,
Per Nordenberg
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