Reducing Flare from Reflective Surfaces

[neil poulsen]

In a phrase, I hate flare. Consequently, it bothers me to see reflective surfaces in proximity to loaded film in a camera. A Deardorff V8 camera back, to my mind, is a good example. Directly adjacent to the film is a perpendicular surface that's painted back. It may be painted black; but I don't see how it can't but help reflect light onto the film. Whether or not it's by an appreciable amount, I don't like it.

So, I ran across a solution I thought I'd share in this thread. It's an 8.5"x11" sheet of black, pressure-sensitive, black felt that I purchased at a local Michael's craft store. It has a paper backing that can be removed to reveal adhesive underneath. Actually, they have two kinds of black felt of this type. One is rather flexible and similar to cloth. It's hard to cut and use.

The second is a much firmer, sheet of black felt that can be easily cut into eighth or quarter inch strips using a matte cutter. The adhesive is relatively strong, and this makes it easy to apply. The photos do a good job of showing its use and effectiveness.

There's not much to add. I plan on purchasing several sheets as a lifetime supply.

[Peter De Smidt]

Looks good. Here are some other options:

http://www.edmundoptics.com/lab-prod...material/1502/

http://fpi-protostar.com/flock.htm

http://araxfoto.com/accessories/flock/

[neil poulsen]

Looks good. Here are some other options:

http://www.edmundoptics.com/lab-prod...material/1502/

http://fpi-protostar.com/flock.htm

http://araxfoto.com/accessories/flock/

Peter, Did you notice; your 5000th post. Jeepers.

What I have is certainly better than the black paint. But, I look forward to checking out other products. Thanks for posting these links.

Not that cost is an issue, with the limited amounts of material that are needed. But, the Michaels material is less than $1.50 per sheet.

[LabRat]

I overhaul telescopes, and flocking material + baffles inside do allow for greater contrast and lower flare... The different materials work well... I have used the Michael's materials, but they can be a little "hairy", but one solution is to go over it fairly quickly with a heat gun to melt back the wayward "hairs"... The industrial felts are more closely cropped, and more easily cleaned with a shop vac attachment...

Though with inside cameras, I have gotten a little compulsive to eliminate ALL felt surfaces as they catch and release dust and lint at the wrong times (esp with a Graflex RB) but do minimize possible reflective surfaces, so I have been going to model railroad stores and finding wood or plastic "clapboard" material for making model buildings, and dusting over with ultra flat black spray paint, and installing on surfaces that might reflect the light rays... Works well and easy to vac!!!

All good things!!!

Steve K

[EdSawyer]

I use the flocking paper (self-adhesive) too, it's better than any paint or felt. I am overhauling a Graflex RB right now and am on the fence about using the flocking paper. It can have a tendency to shed, perhaps not as bad as felt but more than black paint... and the self-adhesive stuff doesn't adhere to painted wood all that well. :-/ Steve, what specific areas do you address in a Graflex RB and how? (Pics would be great) I have it fully stripped at the moment so anything is an option. I am tempted to try the flock paper I have but not sure if it would be more trouble than it's worth... mostly thinking about the inside of the "box". Also the felt for the rotating back (between the two brass panels - is there anything better to replace that? It needs to be somewhat low-friction and also be a light trap...

[Jac@stafford.net]

This thread should be on the first page. Great stuff.

Like others I to use flocking paper. A tip about cleaning - a mildly adhesive lint roller works wonders to restore it to like new.

While paint is not ideal, Testors 1249 flat black works especially well. It's really flat and the nozzle & spray pattern intended for modeling detail is great.

[LabRat]

I use the flocking paper (self-adhesive) too, it's better than any paint or felt. I am overhauling a Graflex RB right now and am on the fence about using the flocking paper. It can have a tendency to shed, perhaps not as bad as felt but more than black paint... and the self-adhesive stuff doesn't adhere to painted wood all that well. :-/ Steve, what specific areas do you address in a Graflex RB and how? (Pics would be great) I have it fully stripped at the moment so anything is an option. I am tempted to try the flock paper I have but not sure if it would be more trouble than it's worth... mostly thinking about the inside of the "box". Also the felt for the rotating back (between the two brass panels - is there anything better to replace that? It needs to be somewhat low-friction and also be a light trap...

Ed, the best thing about an RB is that there is a # of baffles internally, so probably the best LF camera in that regard... The biggest upgrade area would be the seal around the up mirror position, as this is a coarse felt material, and subject to the windblast of the rising mirror... There is probably a lot of dust + lint clinging to the seal there, and should be replaced... I have used (I think) some closed cell rubber window sealing material to replace it with (3/16" X 3/8" I think offhand)... It stops the thunk of the mirror differently, but I have also considered adding sorbothane where the GG mask corners meet the bottom of the mirror for further dampening, but haven't tried it yet... (I also suspect that Graflex might have "syncronized" the upper mirror thunk, with the counter jerk of the releasing FP shutter to counteract those forces...)

One hidden feature I found on many Graflex GG cameras is on that bottom plate that covers the lower FP assy is coated with a tacky grease that holds/collects dust, debris (I have found metal chips/shavings on it), lint, etc, so if you remove/clean that, at least put a strip of heavy duty double sided carpet tape back there to continue it's duty... (One can also put a strip somewhere in the lower part inside of other cameras to catch free debris...)

My Graflok conversion plate had some exposed felt near the film on the inside, and I glued some "clapboard" radius pieces over it to cap that lint source...

You can look at other open planes that can support that "clapboard" hobby material (like on the bottom of the mirror) for the flare thing, but figure that with most landscape shooting is that the sky above is usually the bright area, so after the lens, that will be the area on the bottom of the camera... But keep any treatment simple to clean, as stuff will come to rest there, and with that mirror + FP shutter flying, lint will fly around in there like an old newspaper on a subway track uncleaned... :-) I finally got mine clean, and shoots clean...

Steve K

[EdSawyer]

Steve, thanks for the info. i have used the rubber foam weatherstripping to redo light seals on an Arca Reflex, I still have some of that left. Good points re: the felt on the mirror. I ordered a new mirror recently, since mine is not mint (but definitely usable, but since I had it out already I figured why not...), and the cost was reasonable, so we'll see how that turns out. I had thought of putting the flocking material on the back of the mirror and internal sides of the camera - not sure yet. I am worried about it shedding. I did remove that bottom plate below the lower curtain- good tip on the doublestick tape there. I will add some of that.

I will do a DIY graflok conversion, I already re-glued the felt between the 2 pieces of the rotating back. It's generally covered from the film area, but maybe sealing that edge where it meets the inner brass area would be worth doing.

There's also a felt "washer" on the left-hand side of the mirror shaft, that seals the area around the mirror shaft pivot, that could probably be replaced with weather stripping foam instead. (this is on the opposite side of the mirror controls).

I thought briefly about shortening the mirror itself since I already have it out, mainly to allow use of shorter lenses (like the aero ektar or a xenotar 150). It would require giving up the light-proofness that the mirror offers when down, but if one was careful about when the darkslide was open, it should be a non-issue. The shutter is enough of a light trap, and the mirror blocking light is just a bonus really (which allows winding the shutter with film exposed and not exposing the film, but it seems like it would be easy enough to work around not having that advantage....)

-Ed

[LabRat]

On topic:

The best thing to do to reduce reflecting surfaces is to minimize them... If there is a flat surface near the film area, try to bevel the edge so it does not reflect directly to the film area (if you can)... Visualize the light rays as they would travel through the camera, and remember the law of incidence/ Light will reflect off a surface at the same angle that light hits it... So if the surface is tilted away from the ray path, it will not reflect towards the film... Go through the entire camera system and see if there might be an area that can reflect, and look if that might occur when using movements...

Ed;

You may not have to do much to your RB for internal reflections, as the camera has a # of baffle steps in it to cut-off any excess of the IC, so not needed... (I recently have seen some contact prints from EW's 3X4 Graflex, of images such as his portrait of Igor Stravinsky, and marveled how much snap and nice classic contrast he managed to get with un-coated lenses, and I think it has a lot to do with that well baffled camera...

I wouldn't try to shorten a mirror for a couple of lenses, as there are other nice (+ cheeep) lenses to try... The very fast lenses I have tried can be mushy wide open, but look OK stopped down to f4.5, so the range of Tessars available give quite a bit of that effect, and I even have some Xerox copier Tessars that would probably work well for the special effects, easy to mount, and only cost about $20... (My SF lens for my 4X5 RB is a Gundlach Hyperion, and is a normal size mounted...) So there are other options...

The only thing that makes me want to get the tools out is that when using a 12" Artar type lens in vertical (portrait) orientation, I get a little cut-off, probably from the bottom of the mirror baffle that I'm tempted to trim, but I hope to find a true tele in the future, so my camera is not at full extension where this occurs...

Look for Bert Saunders instructions on the Graflex site for setting the top GG to match the new rear (slightly extended) GG setting by slightly raising the top GG, it works, when you do your conversion... If you can't find it, I might have a hard copy somewhere... The felt in between the adapter seems to not be a problem, as it is outside the camera... Any questions??? Give me a shout...

Happy Holidaze...

Steve K

[LabRat]

Addendum;

I was just giving my Graflex D R/B an internal cleaning before another shoot and noticed something helpful...

I noticed that when aiming my camera at a very brightly lit wall (while looking through the back with the GG panel removed, but with a lens installed), the inside was dark, but I could see a faint glow reflecting on some internal surfaces, so these would be areas to address in terms of internal reflection treatment spots... (The Graflex had a minor reflection where the camera body and front bellows joined)
I figure that most large + smaller film cameras can be eyeball inspected this way and treatments added where needed...

Open or remove the back, and tightly close a focusing cloth around you and it, and look for any reflective glows on surfaces, bellows, etc... You can also aim a very bright flashlight off-axis into the front of the lens and see how the light might reflect inside (as a brutal test)...

Happy Hunting!!!

Steve K