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neil poulsen
15-Dec-2016, 21:52
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
16-Dec-2016, 03:55
Looks good. Here are some other options:

http://www.edmundoptics.com/lab-production/general-tools/light-absorbing-black-out-material/1502/

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

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

neil poulsen
16-Dec-2016, 05:17
Looks good. Here are some other options:

http://www.edmundoptics.com/lab-production/general-tools/light-absorbing-black-out-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
16-Dec-2016, 06:00
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
16-Dec-2016, 07:48
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
16-Dec-2016, 07:59
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
16-Dec-2016, 09:01
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
16-Dec-2016, 10:49
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
17-Dec-2016, 07:02
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
12-Jan-2017, 06:12
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

EdSawyer
12-Jan-2017, 07:04
Steve, good thoughts. I have used that technique on various cameras at times, to find the reflective areas.

I am in the final stages of a re-build on my 4x5 Graflex RB Super D, I'll start a thread on it sometime soon. for the most part I didn't do too much to address reflections yet, since as you mentioned the stock design covers that area pretty well. I did touch up some areas with some Krylon Ultra-flat black (from their camo spraypaint lineup). I may use some self-adhesive flocking material too, though I am still concerned about it shedding...

I didn't cut the mirror but did get a nice replacement first-surface mirror cut to the stock trapezoidal shape, and it was only about $45 shipped, (4-6wavelength quality, which seems more than adequate) which I thought was a great deal. My original mirror had some wear so I figured a new one was worth a try.

I am also building a (better) RZ67-based prism viewer, similar to the one I did on my 3x4 RB Super-D, only it should show full 5x5" coverage of the ground glass.

Re: reflections, one thing I did find on some searching on telescope forums, was that some of the textured black paints are better than pure flat black for killing internal reflections. I bought some paint like that but haven't tried it yet. It has some minor texture to it, not as textured as wrinkle-finish paint but more than a regular flat black. FWIW.

-Ed

LabRat
12-Jan-2017, 08:06
Steve, good thoughts. I have used that technique on various cameras at times, to find the reflective areas.

I am in the final stages of a re-build on my 4x5 Graflex RB Super D, I'll start a thread on it sometime soon. for the most part I didn't do too much to address reflections yet, since as you mentioned the stock design covers that area pretty well. I did touch up some areas with some Krylon Ultra-flat black (from their camo spraypaint lineup). I may use some self-adhesive flocking material too, though I am still concerned about it shedding...

I didn't cut the mirror but did get a nice replacement first-surface mirror cut to the stock trapezoidal shape, and it was only about $45 shipped, (4-6wavelength quality, which seems more than adequate) which I thought was a great deal. My original mirror had some wear so I figured a new one was worth a try.

I am also building a (better) RZ67-based prism viewer, similar to the one I did on my 3x4 RB Super-D, only it should show full 5x5" coverage of the ground glass.

Re: reflections, one thing I did find on some searching on telescope forums, was that some of the textured black paints are better than pure flat black for killing internal reflections. I bought some paint like that but haven't tried it yet. It has some minor texture to it, not as textured as wrinkle-finish paint but more than a regular flat black. FWIW.

-Ed

Reflections on Reflections;

Textured paints will reflect differently due to the "hill & valley" effect of the texture as only the "peaks" have the angle on top that would reflect that angle, but in between them, the "valley" angles would reflect the light off into odd angles (with reduced reflective area)...

Long ago, I had to shoot electronic component gear (for a client) that had deep line grained black aluminum front panels... Shooting them with 4X5 chrome films, they photographed dark as a tomb (flash spotmeter read them as 5 or 6 stops under Zone 5), and I had to figure out how to direct reflectors into just these panels (with full power heads, and kill the spill)... Got it, but examined the panels later to see why they ate light like that, and noticed that the deep V grooves (like an LP record) would reflect light towards the other wall of the groove, and like a light trap, would cancel the reflections in the groove... I made lemons into lemonade by taking that effect into making it work as light traps inside cameras, enlargers, shoot set-ups when light needed to be killed, etc... Finding the V grooved styrene materials for model train buildings could be adapted...

And less fuzzy...

Steve K

Willie
12-Jan-2017, 08:19
Why not have you guys get together and put all this information in an article to post on the front page of this site? We could use some new and updated articles. Your interest and experience can probably make for a good one.

EdSawyer
12-Jan-2017, 11:50
I'd be willing to contribute to an article. Steve has some great info indeed. Interestingly the interior of the Graflex RB Super-D has v-grooved panels for internal reflection resistance, that are also painted flat black. Probably better than most other options.

Eric Woodbury
12-Jan-2017, 12:02
Neil, you sure stirred the pot. Some very good advice here. Telescope flocking materials are helpful. I needed a black surface in a product. I went to the hardware stores and bought all brands of all spray paints to test. Blackness varied by 1 to 2 stops. Amazing. And as someone here noted, surface texture that grows on paint has much to do with this. The darker the surface, however, the more fragile the surface. Careful baffles are a big help. Use a lens hood, French flag, or matte box on the outside to keep excess light out of the camera. Happy shots. --ejw--

Graham Patterson
12-Jan-2017, 12:58
One of the old tricks in the scale model maker's arsenal was to blend fine talc with paint to flatten the surface. It takes some experimentation to get the mix and quantity right, but using a good flat black paint and some powdered talc gives a textured low reflection surface.

Andy Eads
12-Jan-2017, 13:03
Caution: some flocked materials reflect infrared light very well. If you intend to shoot infrared, test the material first.

Willie
12-Jan-2017, 13:15
Maybe someone could get a deal on the paint/coating used on the SR71 spyplane? I understand it does not reflect much of anything. Supposed to be the lowest reflection and blackest black around.

Andy Eads
12-Jan-2017, 13:37
This is wonderful stuff if you can afford it. https://www.acktar-store.com/

Jac@stafford.net
12-Jan-2017, 14:07
Maybe someone could get a deal on the paint/coating used on the SR71 spyplane? I understand it does not reflect much of anything. Supposed to be the lowest reflection and blackest black around.

:) I'm lucky to have a retired Blackbird navigator in the neighborhood, the elder brother of a former workmate. The trick of the SR 71's paint was its composition which changed the nature of radar hitting the paint. The paint could have been color pink, for all that color mattered. For our cameras we need not worry about radar.

Best,
Jac

Peter De Smidt
12-Jan-2017, 14:34
And of course there is paint made with carbon nanotubes, but so far it's delicate and expensive.

On the completely other end, occasionally the macro lads have extolled the virtues of some inexpensive flocked paper at craft stores. One version was better than Protostar, but it was all sold out by the time I heard of it.

Leszek Vogt
12-Jan-2017, 15:17
Neil, you could get a decent anti-flare spray form specialty store that carries mot. pic. items, such as tapes, etc.
No doubt there are some around LA/Holly.

Les

Dan Fromm
12-Jan-2017, 15:33
Long ago, I had to shoot electronic component gear (for a client) that had deep line grained black aluminum front panels... Shooting them with 4X5 chrome films, they photographed dark as a tomb (flash spotmeter read them as 5 or 6 stops under Zone 5), and I had to figure out how to direct reflectors into just these panels (with full power heads, and kill the spill)... Got it, but examined the panels later to see why they ate light like that, and noticed that the deep V grooves (like an LP record) would reflect light towards the other wall of the groove, and like a light trap, would cancel the reflections in the groove... I made lemons into lemonade by taking that effect into making it work as light traps inside cameras, enlargers, shoot set-ups when light needed to be killed, etc... Finding the V grooved styrene materials for model train buildings could be adapted...

I have a couple of TTH aerial cameras whose rear tubes are grooved to control glancing reflections. Whenever I have SKGrimes make an adapter to hang a lens in front of a shutter I have them groove the adapter's interior similarly. It works. The grooves can be quite shallow. Think filter threads.

LabRat
13-Jan-2017, 08:08
Maybe someone could get a deal on the paint/coating used on the SR71 spyplane? I understand it does not reflect much of anything. Supposed to be the lowest reflection and blackest black around.

A funny story about that... There is a Blackbird on outdoor display over at Exposition Park here, and I was outdoors at night there, with only my P&S digital, and tried to take some fairly close up details, but even at wide setting, that thing would not allow the camera to focus at all... I could get it to focus if I turned the camera away from the plane, half depress the shutter, and drag the camera (+ focus) POV back to the plane and then shoot... Just couldn't get it to focus on it... Then I stopped and realized that the finish was absorbing the puny little IR focusing illuminator, as this plane was made to elude MANY different wavelengths costing MANY times my little camera, so lesson learned, you can't shoot a Blackbird with IR focusing at night... :-@

Some other tips about flare reduction;

I had tried some different grooved material to see had it would work... A bit thick, but black vinyl non-skid floor runner material worked well once de-glossed (would work well near a leaky enlarger to cover a nearby wall... CHEAP!!!)...

One could cut-up an old LP record on a bandsaw to make small pieces, but material is also very reflective, so would need de-glossing, but don't just paint a layer too thick over materials, as this seems to "round over" sharp edges that seem to reduce the light trap effect (maybe paint with the thinnest layer, like from an airbrush???),

Model train stores have quite a selection of wood + plastic clapboard & grooved materials so give them a try...

You can also line grain metals like brass and aluminium but as mentioned painting over them can dull the scratches, so if the metal itself can be blackened (anodizing, bluing, etc), that will work better when the cuts remain sharper, to cut reflections better (a way to test is to run your finger over it, and if sharp enough to leave a slight powder mark, that's the material cutting away dead skin cells from your finger...) Giving it pass or two with a stiff power wire wheel or a very coarse sanding block will gouge deep grooves on metals, but don't overdo it, as you want the flat (peak) surface with sharp (valley) grooves on it... Then blacken...

Putting baffles in oversize lens shades works well, but make them large enough so you don't get cut-off using movements... Sharpening baffle edges to almost a knife edge works well, but be careful not to maim yourself while handling shade...

For a good example of camera baffling, look carefully at your postwar metal SLR film cameras... A 35mm SLR has a small area tunnel under the mirror box, but do you ever get reflections from this on your film, despite it being VERY close to your film??? Note the grooves, punched out baffle steps, and angles inside even the cheaper metal cameras, so the mfgs take it very seriously... (And works!!!)

There's something to think about...

Steve K

EdSawyer
13-Jan-2017, 08:28
Thanks for the tip on the Acktar products - those look like nice options, maybe more durable than the typical flocking paper I have used in the past. (definitely more expensive!)

re: SR-71 - although somewhat stealthy by nature, it wasn't designed with stealth as a primary requirement, and the paint isn't all *that* black - I have seen the Udvar-Hazy one up close, in person. Amazing plane though, the coolest plane ever, really (IMNSHO). I expect they put some effort into stealth (paint, coatings, angle of the tail, etc.) but not to the degree of the B2 or F-117A. Plus, ultimately, it didn't matter - the Soviets could easily detect the SR-71 on radar, but had nothing that could intercept it anyway so it was a moot point.

Jac, neat that you have an ex-SR-71 navigator in your neighborhood! I wish that plane was still flying, it's a shame they retired those.

Pfsor
13-Jan-2017, 08:29
One could cut-up an old LP record on a bandsaw to make small pieces, but material is also very reflective, so would need de-glossing, but don't just paint a layer too thick over materials, as this seems to "round over" sharp edges that seem to reduce the light trap effect (maybe paint with the thinnest layer, like from an airbrush???),

Model train stores have quite a selection of wood + plastic clapboard & grooved materials so give them a try...

You can also line grain metals like brass and aluminium but as mentioned painting over them can dull the scratches, so if the metal itself can be blackened (anodizing, bluing, etc), that will work better when the cuts remain sharper, to cut reflections better (a way to test is to run your finger over it, and if sharp enough to leave a slight powder mark, that's the material cutting away dead skin cells from your finger...) Giving it pass or two with a stiff power wire wheel or a very coarse sanding block will gouge deep grooves on metals, but don't overdo it, as you want the flat (peak) surface with sharp (valley) grooves on it... Then blacken...

Putting baffles in oversize lens shades works well, but make them large enough so you don't get cut-off using movements... Sharpening baffle edges to almost a knife edge works well, but be careful not to maim yourself while handling shade...

For a good example of camera baffling, look carefully at your postwar metal SLR film cameras... A 35mm SLR has a small area tunnel under the mirror box, but do you ever get reflections from this on your film, despite it being VERY close to your film??? Note the grooves, punched out baffle steps, and angles inside even the cheaper metal cameras, so the mfgs take it very seriously... (And works!!!)

There's something to think about...

Steve K

Indeed, there is something to think about. The first thing that comes to mind is the nonsensical content of these ideas. All of these ideas can be beaten with simple black flock paper.

LabRat
13-Jan-2017, 08:38
Indeed, there is something to think about. The first thing that comes to mind is the nonsensical content of these ideas. All of these ideas can be beaten with simple black flock paper.

There's that nursery rhyme;

Fuzzy Wuzzie was a bear...

(Metaphor, here...) :-!

Steve K

el french
13-Jan-2017, 12:58
I made a 3d printed hood with internal baffles that works quite well. I designed it using Fusion 360, but if you were proficient in one of the rendering programs like Blender, you could probably get even better baffling.
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