Inverse crop variable ND

[garry23]

As some may know I play around with ML a lot. I believe ETTR, Dual-ISO and auto-bracketing are killer features for a still photographer.

However, there are two other ML features that shouldn't be forgotten: RAW histogram and Bulb Timer.

I recently purchased a second hand Mamiya 45mm 645 lens and tonight attached it to my FotodioxPro 645-EOS Throttle, which gives me a rear variable 2-10 stop ND filter.

I thought some may be interested in this use for ML: http://photography.grayheron.net/2015/06/moving-to-inverse-crop.html

That is setting an LE and controlling the Bulb.

[Levas]

What is the FotodioxPro 645-EOS Throttle exactly.
Looks like a variable ND filter with EOS mount on the back and 645 mount on the front is that what it is 

Would be awesome if there where 'speedbooster' like adapters for 645 to full frame, but as far I know, they do not exist.

[garry23]

@Levas

Yes that's what it is.

I have a throttle for EOS to Sony mirrorless as well.

The advantage of the throttle is that you can use a variable ND on a wide angle or fisheye, without having artifacts created by the polarizer, ie a dark X effect. And of course really wide lenses can't have front filters.