View Full Version : Buying a ND filter... suggestions? Needed with digital?

23rd of July 2006 (Sun), 00:06
I don't know why I feel like this is a silly question, but I am really confused... Not only is there a selection of ND filters, graduated, 1 stop, 2 stop, 3 stop, etc; but then there's a variety of ways of using one and attaching one.

Does anyone use one with digital?

Do you use 'em? If so, which ones? How do you use it? For example, if you are doing a 10 second exposure of a mountain range like the Sierras, with steep dramtic peaks, how do you use a graduated ND filter with it's straight line?

23rd of July 2006 (Sun), 01:29
I use 3-stop and 6-stop non-graduated ND filters, primarily for waterfall photography.

While graduated ND filters can still come in handy in some situations, for the shot of the Sierras you describe I'd probably just take shots identical in every way except varying a few stops in shutter speed, then digitally blend them in Photoshop.

If you're not already familiar with digital blending, there are tutorials on it all over the web. The one at http://www.luminous-landscape.com/tutorials/digital-blending.shtml does about as good as job as most at describing it step-by-step.

It's one of the most useful techniques I've come across in a long time. Not always practical, of course, but what technique is?

In a pinch, where I can't get the two identical (save for shutter speed) photos, I'll sometimes take a single RAW image, and do two conversions of it - differing by a couple of stops. Then blend the resulting two images.

23rd of July 2006 (Sun), 02:24
Thanks! I'm familiar with the photoshop tricks, but I'm just exploring other options. It never occured to me to try non-graduated filters. I had one on my G3, and used it quite a bit. That might be all I need...

23rd of July 2006 (Sun), 03:18
I use the Cokin P system and have 2&3 stop soft ND Grads that help when I am taking sunset/sunrise pics. Soft grads are when you have situations that you describe.

Hard ND grads on the other hand are for those situations where you have a well defined horizon.

ND filters are for slowing down things so you don't blow out the highlights, e.g., waterfall shots or flowing rivers to get you that milky white effect that can't probably be produced in CS2 (well, I haven't tried that yet...)