ND Filters Absortive or reflective

[PCGraflex]

I currently use Kodak ND Series 6 and 7 for most my lenses. The Kodak's are absortive so I am used to those. However, I need to pick up a couple more filters for another lens and have seen both flavors out there.

Does it really make a difference which one to go with?

 

[ic-racer]

I think the main advantage to the reflective filters would be manifest when using them close to a light source.

 

[PCGraflex]

I think the main advantage to the reflective filters would be manifest when using them close to a light source.

Not sure I follow. How so?

 

[Kawaiithulhu]

I think the main advantage to the reflective filters would be manifest when using them close to a light source.

You mean odd light beams bouncing back onto the subject?

 

[Dan Fromm]

http://www.horiba.com/uk/scientific...ical-filters-by-type/neutral-density-filters/

It appears that nearly all (all?) of the ND filters sold for use in photography are absorbtive.

 

[PCGraflex]

http://www.horiba.com/uk/scientific...ical-filters-by-type/neutral-density-filters/

It appears that nearly all (all?) of the ND filters sold for use in photography are absorbtive.

Dan,
Yes, but I ran into these when poking around Edmonds site:

http://www.edmundoptics.com/optics/...rs/reflective-neutral-density-nd-filters/1737

Are these suitable?

 

[Dan Fromm]

They're unmounted and quite small. If you have a lens one would fit on and can mount it, why not? Otherwise, bite the bullet and buy a mounted filter that will fit your lens from a photographic equipment dealer.

 

[Dr Croubie]

Not sure I follow. How so?

I've never thought about it before, but now that I do it does make some sense. Doing portraits with a ring-light where you need an ND to get down to flash-sync speeds at wider-apertures, if you can reflect some of the light back to the face from the ND then it'll all be a bit softer than just the ring light alone.

 

[Dan Fromm]

I've never thought about it before, but now that I do it does make some sense. Doing portraits with a ring-light where you need an ND to get down to flash-sync speeds at wider-apertures, if you can reflect some of the light back to the face from the ND then it'll all be a bit softer than just the ring light alone.

Hmm. Hmm. Hmm.

On the one hand, light reflected off the front of the lens can be a small problem when shooting closeup through glass with a flash. Some of the light is reflected from the glass back to the lens and front of the camera and then back to the glass and back into the lens to the tilm. This is why some aquarium photographers attach something stiff and dark to the lens. The something stiff and dark covers the camera etc.

On the other, the filter will be small and at portrait distances reflections from subject or background to filter to subject will add little illumination. Perhaps a large reflector concentric with the lens. The reflector would serve another purpose too, save the subject from having to look at the ugly photographer.

 

[ic-racer]

Not sure I follow. How so?

The reflective neutral density filters won't get as hot. They [reflective ND filters] are special dichroic filters. For example, use in front of lasers where heat build up in the filter can lead to innacurate results.

The heat generated in an absorptive ND filter, when used on you lens to absorb light from the subject, is so little so dichroic ND filters would have very little use in photography. Hovever, I suspect the dichroic ND filters would be fade resistant.