Is it possible to make your own filters? Of course it would be hard to make something that has even remotely comparable optical qualities of the commercially available counterpart, but I simply can't afford to by a dozen 4" wratten filters to experiment with. I mainly want colours for adjusting b&w film.
A few ideas:
*Ask a print shop to print colour on transparencies?
*Dye a gelatin solution and mold poor-mans wrattens?
*Paint some thin transparent plastic with a clear paint?
Any more sane ideas? Anybody tried a method that worked? Compensation factors would have to be estimated with an exposure meter or something, that's a minor problem.
I've had some success sandwiching colored celophane between lens and a uv filter. Extra care a must to avoid wrinkles, test shots to determine proper f-stop.
Rick
All my square filters are cut from coloured Perspex, alias Acrylic, alias Plexiglas. This is the stuff that comes with the protective brown paper that you just peel off before use.
My 84mm "Cokin" squares are cut out with a hacksaw and work just fine. The surfaces are optically flat and I've never seen image degradation either in camera work or astronomical telescope applications.
The plastic surfaces are much softer than glass but a scratched filter is cheap to replace; about $1 each if I source Perspex off-cuts from the local plastic fabricator.
go to the theater supply store, buy theater filters, use on camera, keep them from getting too terribly scratched. If you're just experimenting there's no need to invest in expensive filters. You'll want a deep red one for cloud shooting and a yellow for everyday shooting. Most other filters are varying ranges of yellow through deep red (like orange.)
All my square filters are cut from coloured Perspex, alias Acrylic, alias Plexiglas. This is the stuff that comes with the protective brown paper that you just peel off before use.
My 84mm "Cokin" squares are cut out with a hacksaw and work just fine. The surfaces are optically flat and I've never seen image degradation either in camera work or astronomical telescope applications.
The plastic surfaces are much softer than glass but a scratched filter is cheap to replace; about $1 each if I source Perspex off-cuts from the local plastic fabricator.
Go to a place that sells stained glass supplies. The one my Wife frequents has hundreds of different colors and textures of glass. They also have tools for cutting the glass. They usuelly have a scrap box with small left over pieces which sell pretty cheap. The choices are amazing!
Rosco or Lee filters about $8.00 a sheet and those sheets are 17x22. Try not to shoot through the scratched parts.
If you are really lucky, you might find a theater supply shop that also does contract lighting and might have a bunch of scraps around that you could have for free.
These gels are not perfect, but should give you an idea of what colors you need. Get a Rosco or Lee filter swatch book and see what you can cross reference to real photo quality filters before obtaining any gels.