Filter Placement

[Chuck_P]

I always place my filters on the front of the lens (I use the Lee gel snap filters) and always making sure that the filter is square with the front element of the lens. But is there any advantage to placing the filter at the rear of the lens?

Thanks

 

[Monophoto]

There are three advantages to putting filters behind the lens.

1. Less concern for flare since the filter is not exposed to direct light.

2. No need for holders when using gel filters - just attach them with a small bit of tape. Can't do that on the front because wind could cause the gel to flop around.

3. Less risk that the filter holder will cause vignetting..

On the other hand, it's a PITA to have to remove the lens board to attach the filter. And when using something other than gel filters, standard filter holders may not work - not all LF lenses have a threaded rear element.

 

[edtbjon]

On the back of the Sinar shutters there is a holder for gel filters and similar. On the Sinar cameras it's easy to unlock the bellows to attach the filter.

//Björn

 

[David A. Goldfarb]

If you use filters behind the lens, it's more important that they be clean than if they are in front of the lens. Gel filters also minimize focus shift, as opposed to glass or resin.

 

[Chuck_P]

Thanks for the info, that's an interesting bit about the reduction in focus shift with gel filters.

 

[pgomena]

After years of fussing with gelatin filters and behind-the-lens setups, I broke down and bought a set of 77mm glass screw-in filters and a few adapter rings for my 4x5 lenses. They screw right into my Lee lens shade setup. I've never been sorry. No worries about damaging the gels, which now are very expensive. Much easier to work with in the field.

Peter Gomena