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Randy
11-Jun-2013, 14:12
This may be a stupid question...or, one that has been a dressed before. I have a few large lenses, for example: B&L 11X14 1C f/4.5. I am using a Packard shutter and would like to be able to shoot at, or close to, wide open on sunny or bright days. As it is I have to wait till dusk to shoot wide open because of the shutter speed with the Packard.

Is there any fairly inexpensive neutral density material available for making filters? Something like a high quality window tint material?

BarryS
11-Jun-2013, 14:40
I had the same issue and found some inexpensive optical resin filters on eBay. I have a set of 1, 2, and 3 stop square filters and just hold them in front of the lens when making an exposure.

Randy
11-Jun-2013, 14:50
Thanks Barry, will have a look. They need to be large, like 6 or 7" square.

vinny
11-Jun-2013, 14:57
Gam, lee, and rosco all make gelatin filters in rolls and sheets (20x24 ish) for lighting instruments/windows. Gam being the most neutral. B&h sells them too.
make some mounts from black/black matt board or plastic.

BarryS
11-Jun-2013, 15:12
The ND filters I got are 4x4, Not sure if you can find larger ones for a bargain. The gels Vinny mentioned are surprisingly good optically, but there are a couple of issues. Since they're used for lighting, vendors don't care about scratches or bends. The bigger issue is that the filters are very delicate, they're thin and bend/scratch easily. If you could sandwich them in between a couple of sheets of thin glass, that would help a lot.

Tin Can
11-Jun-2013, 17:29
I have wondering this also. I considered, but have not done so, making them from exposed LF film.

Expose to a black surface...

Has anybody tried this?




This may be a stupid question...or, one that has been a dressed before. I have a few large lenses, for example: B&L 11X14 1C f/4.5. I am using a Packard shutter and would like to be able to shoot at, or close to, wide open on sunny or bright days. As it is I have to wait till dusk to shoot wide open because of the shutter speed with the Packard.

Is there any fairly inexpensive neutral density material available for making filters? Something like a high quality window tint material?

Jerry Bodine
11-Jun-2013, 21:50
I have wondering this also. I considered, but have not done so, making them from exposed LF film.

Expose to a black surface...

Has anybody tried this?

RM, I don't think it would be cost effective, given the cost of film/chemicals needed + your time, when you consider the price of Rosco's 20x24" ND sheets. Back in March 2012 I contacted them to ask their prices for Window Filters ND.15, ND.3 and ND.6 - thinking to stack them in various ways to achieve additional densities. However, my interest was to slip them between two acrylic diffusion sheets I made as a holder, to be held in front of lens for film pre-exposures (to reduce contrast with normal dev time), I was not particularly concerned about optical quality. Rosco's response was $8.25/sheet. That would allow you to cut whatever size you might need and still have much left over for re-makes. So I'd heed Vinny's suggestions. Just a thought.

Tin Can
11-Jun-2013, 22:30
Thanks for the advice,

I looked at B&H and Roscoe ND gels and I even have a pack for gelling lights for video, but I was thinking a single sheet of film may be less flimsy and having only one sheet would be prefered. What I would prefer is a Lee Big Stopper, but right now it exceeds my weekly allowance.

I mess up plenty of film, so a couple sheets to try making a ND filter is not excessive.



RM, I don't think it would be cost effective, given the cost of film/chemicals needed + your time, when you consider the price of Rosco's 20x24" ND sheets. Back in March 2012 I contacted them to ask their prices for Window Filters ND.15, ND.3 and ND.6 - thinking to stack them in various ways to achieve additional densities. However, my interest was to slip them between two acrylic diffusion sheets I made as a holder, to be held in front of lens for film pre-exposures (to reduce contrast with normal dev time), I was not particularly concerned about optical quality. Rosco's response was $8.25/sheet. That would allow you to cut whatever size you might need and still have much left over for re-makes. So I'd heed Vinny's suggestions. Just a thought.

ridax
11-Jun-2013, 23:02
I too have tested the lighting filter 'gels' (polyesters in fact) for the in front and behind the lens usage and was unable to find any traces of sharpness degradation (but make sure your gel is mounted perfectly flat!). I've also used some of those (the conversion ones from Lee) for taking actual pictures and liked the results.

I believe NDs and gradients and some other filters could be made out of B/W silver films but I wouldn't use those if I can get the dyed gels instead as silver particles are rather large and do scatter part of the light coming through the emulsion. The dye-based E6 films should be better but I'm still not sure they'd get as good as the special filter gels.

Bill Burk
11-Jun-2013, 23:11
Of course you could just overexpose

Tin Can
11-Jun-2013, 23:18
I do have a supply of E6 expired 4X5 and my local lab is $2.25 a sheet. Good idea!


I too have tested the lighting filter 'gels' (polyesters in fact) for the in front and behind the lens usage and was unable to find any traces of sharpness degradation (but make sure your gel is mounted perfectly flat!). I've also used some of those (the conversion ones from Lee) for taking actual pictures and liked the results.

I believe NDs and gradients and some other filters could be made out of B/W silver films but I wouldn't use those if I can get the dyed gels instead as silver particles are rather large and do scatter part of the light coming through the emulsion. The dye-based E6 films should be better but I'm still not sure they'd get as good as the special filter gels.

Randy
12-Jun-2013, 04:39
Looks like some of these gels are available through Amazon.

ashfaque
12-Jun-2013, 06:17
Hope this helps: http://youtu.be/h-iUIJPgZdc

Bests,

Ashfaque

Tin Can
12-Jun-2013, 07:19
Brilliant and he supplies part #'s!

I do have a Lee rubber band universal filter holder which only cost $20.

Thanks!


Hope this helps: http://youtu.be/h-iUIJPgZdc

Bests,

Ashfaque

DrTang
12-Jun-2013, 07:37
you're not gonna stick window tint film behind some lens you spent 1500 on are you??



also..isn't the biggest packard shutter opening like 3.25" or something?

I would make a slot in front of the packard shutter to slip in 4" optically correct wratten gel filters myself

Tin Can
12-Jun-2013, 07:54
I have been known to do dumber things.

Calumet sells Lee Filter Poly's or 'Gels' as a house brand at $20 a pop for 4X4". I have a couple of those delicate tissues. They are optically good...for a short while.

I will buy big sheets to play with, no rules, remember?



you're not gonna stick window tint film behind some lens you spent 1500 on are you??



also..isn't the biggest packard shutter opening like 3.25" or something?

I would make a slot in front of the packard shutter to slip in 4" optically correct wratten gel filters myself

Jim Noel
12-Jun-2013, 08:06
Any company which sells Stage and Lighting equipment will have 12" square sheets of neutral density filters for very little money. I have them from .30 to 3.00 density and they work well.

DrTang
12-Jun-2013, 08:29
.. no rules, remember?


oh fer sure


just struck my funny bone this morning

Tin Can
12-Jun-2013, 08:34
This is my favorite gel.

http://www.ebay.com/itm/370677811466?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649



oh fer sure


just struck my funny bone this morning