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Adjustable ND filter
#1
It's hard to be sure about the impact on IQ, but by all means, an "adjustable" ND filter sounds exiting:



[url="http://www.press1.de/wrapper.cgi/www.press1.de/files/km_kmpk1245_1284611898.pdf"]http://www.press1.de/wrapper.cgi/www.press1.de/files/km_kmpk1245_1284611898.pdf[/url]



PS: It's still not presented in the official (international) site though ([url="http://www.kenkoglobal.com/filters.html"]http://www.kenkoglobal.com/filters.html[/url])



Serkan
#2
Variable ND filters are not that new.

Singh-Ray Vari-ND is around some time.



You can put two linear polarizer together: Voila! Vari-ND!

Or use two linear polarizer filter gels.



To test the application you can try 2 circular polarizers. Screw in the first and just hold the second one reversed in front of it. Output is crap, serious problems with "hot" spots.



Ciao, Walter



PS: Linear polarizers may cause phase detection AF and exposure measure to fail. Use live view instead.
#3
[quote name='Walter Schulz' timestamp='1287497315' post='3690']

Variable ND filters are not that new.

Singh-Ray Vari-ND is around some time.



You can put two linear polarizer together: Voila! Vari-ND!

Or use two linear polarizer filter gels.



To test the application you can try 2 circular polarizers. Screw in the first and just hold the second one reversed in front of it. Output is crap, serious problems with "hot" spots.



Ciao, Walter



PS: Linear polarizers may cause phase detection AF and exposure measure to fail. Use live view instead.

[/quote]

Just use one circular pol. filter (on the lens) and a linear pol. filter on that one. That will give the same result as 2 linear ones. But then you have a circular one for normal usage.



And together this way they also avoid trouble with metering and/or AF.
#4
Any comments on "Polarizing Effect Cancellation" mentioned in the document?



Regards,



Serkan
#5
No problem if the whole mechanism has 2 rings able to be moved.

First ring determines the filter factor, then rotate the second ring (and therefore both filters) until the polarized light comes through.

You can test it for yourself if you have two filters and a LCD/TFT monitor, it's light is polarized.



Don't know if this mechanism is used by Kenko.



Ciao, Walter
  


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