The Watcher

This link has some good information on Neutral density filters. Also check out the links at the bottom for more info.
http://en.wikipedia.org/wiki/Neutral_density_filter

rayford2 Loc: New Bethlehem, PA

What adds to the confusion of ND filters is the different numbering systems used by different manufacturers.

rayford2 Loc: New Bethlehem, PA

Also note that some companies use the FILTER FACTOR as the size. (see the previous chart)


Here's a calculating chart using OPTICAL DENSITY (see the previous chart) and shutter speed for ND filters. I hope this helps someone.

Wayne'spictures Loc: Souderton, Pa. 18964

You have gotten some good info. and some not so good. I will suggest you look at the sites I have listed below. The "Cambridge in colour" has a lot of tutorials that are very good. The last site on the list from Singh-Ray Filters shows some great examples of using filters. They all say it a lot better than I could.
____________________________________________

FILTERS
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http://www.cambridgeincolour.com/tutorials/neutral-density-filters.htm

http://www.cambridgeincolour.com/tutorials/graduated-neutral-density-filters.htm

http://www.cambridgeincolour.com/tutorials/camera-lens-filters.htm

http://singh-ray.com/" rel="nofollow" target="_blank">http://www.http://singh-ray.com/

http://singh-ray.com/inthefield.html" rel="nofollow" target="_blank">http://www.http://singh-ray.com/inthefield.html

http://singhray.blogspot.com/" rel="nofollow" target="_blank">http://www.http://singhray.blogspot.com/

This should help you decide how & when to use different filters, especially ND filters.
Good luck & Happy photography.

NormPR

Thank you all for the information, it will help me to know what I am looking for, and what filter(s) to buy...Norm

rayford2 Loc: New Bethlehem, PA

Great info, Wayne's. Thank you.

frangeo Loc: Texas

I do the same thing only with out a ND filter. I simply touch the +/- button on my Nikon and tone down the scene to keep the highlights from blowing out. It’s like having 20 ND filters built into the camera. Now for dull scenes I have all those adjustment to brighten the scene. No filter necessary. That’s why good cameras are expensive.

Wayne'spictures Loc: Souderton, Pa. 18964

Read more about ND filters. The camera doesn't do the same thing and won't get the same results. What you are doing in camera is surely needed many times to adjust the light in the photo you are taking. But again the results will NOT be the same as the results when an ND filter is needed. I will not try to fully explain but you should read in several manufactures info. about when & why using an ND filter will improve your photography. Having the best camera & lens is only good if the photographer really knows how to get a good photo. That's what makes it so interesting. It's easy to learn a lot about it on the internet, like on sites like this. I always find new things to learn about photography and all it's hardware.
After you've read & tried more, let us all know what the results were.

frangeo Loc: Texas

If the ND’s work for you then enjoy. I read the hype from the manufactures and still find no real benefit over adjusting your camera properly. I say hype because it is advertising to get you to buy their filters. Of all the pros I know and work with not a single one uses a ND filter. It was a valuable tool for film cameras but not for digital. Lowering your ISO, adjusting your camera settings or using your +/- override can give you the same results as the ND filters. Also watch what you stack on the front of auto focus lenses, they have a tendency to confuse the camera and you loose sharpness. Look that up on the internet. Don’t let my point of view discourage you. Never stop learning. Don Blair and nationally know photographer and teacher embraced digital imagery in his late 60’s. He was so famous that Hasselblad gave him a custom made camera in celebration of his achievements in photography. Again, never stop learning. ( see image – NO filters )

Wayne'spictures Loc: Souderton, Pa. 18964

I am glad to hear there are professional photographers ALSO that do not find that ND filters will improve their photographs because their cameras and lenses deem the filters unnecessary ever. My Leica camera and lenses are not today's newest technology. Cameras and lenses improve almost every day and I know I can not keep up with them. So thanks for the information.
Subject closed.

rayford2 Loc: New Bethlehem, PA

The only exception I would take to the above are some specialty ND filters such as the graduated types. These have a definite purpose for digital cameras under certain circumstances.