Bayonet 58mm convertor? Neat idea or am I being dumb . .

[Graham Bernard]

I've just read and realised something. I've put off thinking/buying 2X TeleConverter from Century or whovever - but have been put off by the need to "screw" on the 58mm threaded lens. Is there such a thing as a 58mm threaded convertor to give a bayonet option? Or am I missing the plot here? Could it be that the focal plane will be majorly effected, this resulting in manufacturers not wanting to design, construct and retail such a product?

Grazie

[Ken Tanaka]

Graham,
Not to declare that such a gadget doesn't exist but I sure do not know of one.

Indeed, the location of the adapter with respect to the main lens is a matter of some precision. Those who, for example, mount a filter between an adapter and the lens (for inexplicable reasons) do indeed throw this alignment off by a few millimeters.

[Graham Bernard]

Pity - But you don't surprise me.

On another tack, as you make me think, I DO use a filter between the WD58 and the Cammy lens. Not recommended?

Grazie

[Ken Tanaka]

No, not recommended for the reason, above. But judge its merits for yourself.

What filter do you use and for what reason?

[Jeff Price]

I didn't use a real filter between the teleconverter and my GL1 but I did use a filter with the glass removed in order to minimize wear and tear on the threads. It might have meant more vignetting occurred at wide angle (not that I use that). It might have affected auto-focus a little but not that I noticed.

I have stopped using the intermediate set of threads though and now just mount the lens straight to the camera. No real reason other than a feeling that using the filter might not be the best thing to do.