sel16 and ND filters?
I apologize in advance if this has been asked/answered. I've searched Google and here on the forums and couldn't find the answer.
I would like to know what size circular ND filter would be big enough so that I would not get any vignetting on the 16mm lens? As you can see from the picture below I am getting some noticeable vignetting and although not horrible I was hoping someone knew from experience what size filter (with the use of stepup rings) would eliminate this. As an oh by the way, I am looking to upgrade my homemade welders glass filter (49mm to 52mm stepup ring with piece of welders glass inside) to a true 10stop ND filter.
Flickr Photo stream: http://www.flickr.com/photos/jacobcaddy/