Re: Maximum Extension Tube Length

[Flavio Minelli]

Shel Belinkoff wrote:
> 
> Is there any theoretical or practical limit to the length of
> extension tubes?  Could a 150mm - 200mm length be used with a
> 200mm macro lens without any image degradtion?
> ...

Hi Shel,
I suppose there's a practical limit where the lenght of stacked tubes
starts getting long enough to bend slightly under the weight of the
lens.
Besides using 200mm of extension with a 200mm lens already capable of
1:1 reproduction ratio seems a little excessive.
If you want 2X or more you could start looking into lens stacking and or
reversing.

Flavio
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