8mm Forum: Reflections from the Ceiling!

This is topic Reflections from the Ceiling! in forum General Yak at 8mm Forum.

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Posted by Paul Mason (Member # 4015) on November 08, 2015, 03:52 PM:

I've just increased the size of of my projected picture in my lounge with a new lens but I notice that an awful lot of light is bouncing off the white ceiling and back onto the screen. The picture is losing a lot of contrast. Has anyone else noticed this. Short of painting the ceiling black is there anything that can be done? I suppose some sort of canopy over the screen top might work but it would have to be dark, light in weight and as rigid as possible.

Posted by Clyde Miles (Member # 4032) on November 08, 2015, 04:54 PM:

paul what is your throw from projector to screen? are you using a 25mm short lens?

Posted by Paul Mason (Member # 4015) on November 09, 2015, 03:22 AM:

Hi Clyde,
I am using a 25mm lens on my Bell & Howell 642 at a throw of about 11 feet (3.3 metres).

Posted by Paul Mason (Member # 4015) on November 16, 2015, 05:07 AM:

I must have answered my own question. Another possibility would be to place the screen behind an open window? Cold though in November here or through an open doorway!

Posted by Steven J Kirk (Member # 1135) on November 16, 2015, 06:25 AM:

Paint the ceiling black...

Posted by Paul Adsett (Member # 25) on November 16, 2015, 01:34 PM:

Light scatter from the ceiling and side walls will definitely ruin the contrast of your projected picture. I painted the walls of my screening room a darkish beige,the walls were previously white. This made a significant improvement. But I was still getting a lot of light scatter from the white ceiling. I did not want to paint the ceiling black because I wanted to retain a cozy ambience in my cinema, and I thought a black painted ceiling would make it look like a tomb!
So, I made up several 2ft x 4ft rectangular frames of 1/2 ins x 3/4 ins wood strip, and covered them with black and burgundy felt cloth, suspending the frames from the ceiling by small hooks and eyelets. The frames are extremely light indeed, and present no load at all on the ceiling. I can tell you Paul that this made a HUGE improvement in the projected picture quality. And, I think the panels are quite attractive and add to the cinema like ambience of the room.

Posted by Andrew Woodcock (Member # 3260) on November 16, 2015, 01:38 PM:

Looking better than ever Paul! What a classy cinema room you really have there! Simply beautiful Paul.

Posted by Paul Adsett (Member # 25) on November 16, 2015, 01:45 PM:

Thanks so much for your very kind comment Andrew. Yes,I am very happy with it, and its a wonderful place to go and forget about the troubles of the world we live in, and wallow in the nostalgia of the classic cinema. [Smile]

Posted by Brian Fretwell (Member # 4302) on November 16, 2015, 02:48 PM:

I remember when they restored an old London cinema they thought the ceiling was dark brown. It wasn't - it was originally white (I think the scree was well recessed from the main auditorium) but had been stained dark brown by all the smoking that had taken place in it over the years.

P.S. I'm not suggesting you smoke to excess to cure the problem [Big Grin]

Posted by Jean-Marc Toussaint (Member # 270) on November 16, 2015, 06:42 PM:

Like Paul, I chose also to avoid paint on the ceiling. I tried and although I had picked a rather mate dark tint, it still had a reflective effect.
I found some rather inexpensive self-adhesive carpet tiles which, luckily match the color of my walls.
Contrast has increased tremendously and now that light is no longer bouncing everywhere, 3D projection is better than ever.
(Note that for this picture, the blue fabric cover for the screen casing is missing as I'm currently improving the masking system)

Posted by Paul Adsett (Member # 25) on November 16, 2015, 08:28 PM:

Jean-Marc is right, even matt black paint is reflective. Black felt though, seems to be almost 100% absorptive of light.
By the way, to our old friend Jean-Marc, I say Vive La France!

Posted by Jean-Marc Toussaint (Member # 270) on November 17, 2015, 01:07 AM:

Thanks Paul! [Smile]

Posted by Paul Mason (Member # 4015) on November 18, 2015, 08:49 AM:

Wow, some great ideas here. Thanks particularly to Paul and Jean-Marc.

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