non-reflective coating

Martin, Would a light frosting do the job? Example - there is a grade of picture-framing glass known as "non-reflect" which works well in that application. As far as I can see, it is just slightly etched (frosted) on one side. You should be able to source either that type of glass, or that treatment on a standard glass sheet, from a glass merchant for a fraction of the price you mention.

Frank

Martin, Would a light frosting do the job? Example - there is a grade of picture-framing glass known as "non-reflect" which works well in that application. As far as I can see, it is just slightly etched (frosted) on one side. You should be able to source either that type of glass, or that treatment on a standard glass sheet, from a glass merchant for a fraction of the price you mention.

Frank

Martin, Further to Franks reply. Yes, you can get 2mm non reflective glass, in many grades. For a piece 500mm x 500mm, from a cheap $AUD12 for the machine etched, to Museum glass at around $AUD200. But, you want this for another type application / reason ? There are ways to reduce glare, please advise precise use / situation and I will try to assist with your question. Regards, Les

Sure does....an old photographer's trick. HAIR SPRAY..

Thanks Frank and Les for your replies.

I want to use this piece of non-reflective glass to film through it. If I use a normal piece of glass I can film through it but I also film the camera reflected on the glass. I have tried a sample piece of transparent non-reflective glass and it?s good for the application. However I need a bigger piece, 500mm^2.

The non-reflective glass used for framing pictures it?s not good for this application, as it?s not totally transparent.

Martin.

figjam62 wrote:

Hi Moonraker,

I?ll try the hair spray thing, it sound very intriguing. However I want to use this piece of non-reflective glass to film through it. If I use a normal piece of glass I can film through it but I also film the camera reflected on the glass. I have tried a sample piece of transparent non-reflective glass and it?s good for the application. However I need a bigger piece, 500mm^2.

I suspect that the hair spray may make the glass not transparent as well as non-reflective.

Martin.

Mo>>

Ok Martin, I feel there are possibly a few options here.

1/ Find a picture framer and see if you can get your hands on some Tru Vue Museum glass. This is a little pricey, but worth checking out. Framers with samples in their shops, are forever cleaning this product, as customers are always walking up and touching the glass, thinking there is nothing there. This is very anti glare, AND would be very transparent to film through.

2/ Tilt the glass down at an angle, as long as there is no light from that area, it could reduce glare enough for your needs. Try a black sheet on the ground and tilt the glass maybe up to 45 degrees towards you. Shopfront glass is sometimes tilted forward slightly as a means to reduce reflection and glare.

3/ You can't you find a piece of your existing sample non reflective glass at 500mm square ? If it isn't traditional non reflective picture framing glass, what product is the sample of you have tried ?

I know the cheaper non reflective glass for picture framing is blurry if moved off the print surface for example, more than a couple of mm.

I'm sure a picture framer in the UK could source you some TV Museum glass, and show you some samples.

Regards, Les

I spent many years in the photo business...

Use very thin mists of hair spray. Or matte finish photo spray might also work. Acetone or lacquer thinnner will remove it if you get too much. Trial and error seems to be the way to go. Also, you could put the camera into a matte black box/bag with only a peek-hole for the lens, so that nothing is there that would reflect. It may take both. Also the glass may have to be set at an angle to the optical center of the lens to deflect any reflections off to the side so the lens won't catch the reflections.

Do you mind sharing what you are trying to do? Why film through glass, anyway? You doing something naughty?

Thanks very much to you all for your input.

I think that Les put me on the right track with the Tru Vue Museum glass. The glass that suits me better is Tru Vue Reflection-Free, now I?ll try to get a price, hopefully it?ll be much cheaper than the £260

+£150 shipment this German company was charging me.

The sample of non-reflective glass I have is from a local glass merchant in Nottingham. I don?t know the name of this type of glass but I think it?s not used for framing, the sample I have it?s 4mm thick and the one I could buy from the German company is 6mm thick.

On the other hand I find very interesting Moonraker suggestions about the hair spray. I don?t think it?s what I need but I?m going to try anyway. I also have a print with a cheap frame in my sitting room that reflects most of the light, and I?m going to give it a bit of hair spray and see how it looks! I?ll try the black box with the pin-hole as well.

The application it?s nothing naughty unfortunately. I?ll try to explain briefly: I?m doing some research at the University of Nottingham about virtual interfaces in mixed reality (yes, I?m a computer geek). Basically the user of this system wears some special goggles that allow him to see some virtual interfaces, keypads, buttons, etc floating in front of him. Then he can operate them directly with his hand. The hand movements are recorded by a camera and a software, in which I?m working at the moment, tracks the hand and works out when the user is touching some of these virtual interfaces.

As a first experiment without goggles, I wanted to draw these interfaces on a piece of glass and record the hand movement through the piece of glass. So that when the user types on a keypad drawn on the glass the software detects the key presses and writes on the computer screen what the user typed on the glass. I first tried with a piece of normal glass and the reflections stop the software working properly, that?s why I thought in using non-reflective glass.

Well, I think I have a few ideas to get entertained for a while. Thanks again.

Martin.

Mart> Hi there,

The reason you are seeing the camera is that there is too much light on the CAMERA side of the glass. There are several ways you can deal with this. 1) Darken the room where the camera is (which can be hard to do if you are simply shooting an outdoor scene through a window). 2) add a cone of dark paper to the front of the camera, and, press it up against the glass. Again...depending on the situation, this can be a problem. 3) Probably the best solution for you would be to put a polarizing filter on the camera lens. The bad news is that you lose a bit of light, which requires exposure compensation. The good news is that you can minimize reflections. It does work better with the glass at an angle....but even for straight on shots should do well enough to pretty much remove the camera image from the recording. You might want to track down a photo supply store in your city that caters to professionals, and, talk with them about this. They will typically have a wealth of information on it, and, samples that you can try out. Regards Dave Mundt