GH2 Learning to use a variable ND

[Brandon Rice]

I recently picked up a variable ND filter for my Rokinon 85mm f1.4. While I LOVED using it on a shoot last weekend, I made the mistake of keeping the lens WIDE OPEN the entire time I was using the ND... this caused a lot of my shots to be softer than I would have liked. It worked OKAY in this case, but want to make sure it doesn't happen again. I just ordered ND's for my other prime lenses (16mm, 50mm) and want to know what the "sweet spot" would be for me to keep these lenses dialed to? I'm thinking f2.8?

Thoughts?

Thank you!

 

[wwjd]

I think it all depends on the desired result: DOF or soft or sharp or vignetted, etc

http://www.dxomark.com// and http://www.photozone.de/

have helped me know the sweet spots of lenses

before you buy a bunch of ND's, consider adapter rings (if your current one is large enough) then you can reuse that variable on many lenses for little expense

 

[Brandon Rice]

I'd rather have one per lens if possible... but good points.

 

[stoneinapond]

I'd rather have one per lens if possible....

That can get quite expensive. Go with a good quality ND filter (which will cost you) in a larger size than your biggest filter dimension unless you are never going to buy another lens. It really is not a hassle to put one on for a particular situation. Are you doing rapid lens changes all the time?

Also bear in mind as the previous poster pointed out, a variable ND filter is there as an additional control mechanism for choosing an appropriate aperture depending on specific light situations. It's OK if you are always shooting with a fixed aperture, but that kind of defeats the whole idea of being able to vary your DOF.