Placement of flush lighting for illuminating pictures

[smjxm09]

I will be illuminating my cinema room by 2 rows of tilting flush mounted ceiling lights. I need to work out how far my ceiling lights need to sit away from the wall to produce a nice lighting effect for the pictures they are also going to illuminate. The top of the pictures will be around 600mm down from the ceiling. Due to the ceiling joists I seem to me restricted to either placing the lights between 140mm-215mm out from the wall, which is an angle of about 15 degrees or 335mm-425mm out from the wall, which is an angle of about 30 degrees. This is the maximum the lights will tilt. Anyone got any thoughts?

[LCR_Dave]

electrician here most flush downlights that can angle are called gimbals, they dont give you much tilt so the nearer the wall the better,, get as close as you can for the most flexibility when illuminating pictures, failing that you can use eyeball light sittings that sit lower out of the flush fitting but they arew old hat now to be honest and look cak, use low voltage rather than mains voltage lamps to get a brighter whiter light for lighting up pictures ect, and always add dimmers to give you complete control but watch the loading of the dimmers, try not to go over 300-400w per dimmer for best results, ie not to much humming ect. hope this helps mate
Dave

[Zog]

Pretty much concur with the above, but try to get a gimbal with decent adjustment.. >30 degrees.

If you need to put them too close then any substantial frame will cast a shadow.

Also if there is any texture in what you are hanging, then illuminating from directly above risks exaggerating this.

Select a fitting with the greatest possible adjustment and then try a slightly wider beam than normally supplied. Standard tends to be 24 degree, but I would recommend 38 or even 60 degree. It will obviously depend upon the size of the picture to be illuminated and the adjustment angle of the luminaire selected.

Also, the closer the lamp to the picture the more visible the striations produced by the reflector will be.

For the ideal fitting check out the Deltalight Carree 145 on deltalight.com. This is rather expensive but there are a few imitators about.

[smjxm09]

Thanks for those great replies. I have already bought the dimmer which is a Lutron Rania single white which is mains only and rated at 500w so it is too late to go down the LV route.

I am having a garage converted so the new cinema room will be only 2m 20cm wide but 5m long. I am planning to have installed a total of 10 ceiling lights in two rows of 5. The gap will be 83cm between the lights. I was looking at getting 2 packs of B&Q lights which sell at £29.80 for 5 including halogen bulbs rated at 50W. This means that the dimmer could run at max power but in reality I would imagine that they will be preset to lights well below max.

Each light will serve two functions, to light the room and to light enlarged photos of various sizes. In my mind shadows will play an important part. I would be looking for a shadow on the wall by the light and an ark of light to strike the wall around the 600mm mark below the ceiling thus the requirement for a tilting light. B&Q do 3 types. 20 degrees, 27 degrees and 30 degree. I am assuming these sort of lights can do this type of lighting.

Would these lights at this price be rubbish or a bargin. An alternative would be something like this http://www.mr-resistor.co.uk/item.as...3&r=156&i=1877 from a quality lighting shop but at £11 each plus bulb there is a major price difference.

Anyway I have started a thread with photos of the project at Yet another boring internal garage conversion project. so you can see what is happening.

Oh I nearly forgot, what is a striation?

[LCR_Dave]

that dimmer should be fine for low voltage just make sure you get dimable electronic transformers, those lights from b&q are mains voltage halogen the lamps are called gu10 and when you dim them you normally need to de-rate the dimmer so for example 400w of gu10 lamps need a 500w dimmer, unless the dimmer is a soft start then you wont have too much of a problem, i personally wouldnt touch those lights, try and get to an electrical wholesaler you will get a much better quality light and in a style that you like as there is a wide selection available, hope this helps abit more, any questions just ask mate

[LCR_Dave]

also the lights in the link are fine mate dont think you can go far wrong with them if you wanted to go the mains voltage route

[smjxm09]

Thanks for your continuing help. The Lutron came in two versions. Mains only, rated at 500W and universal, which also supported LV and was rated at 450W. As I was looking at 500w I dismissed the universal model.

The dimmer will be set to illuminate the lights over a 3 second period and to dim them over a 15 second period so is that called a soft start?

Also why do people go for a LV lighting with transformers over mains voltage lighting?

Do the lights have to be fitted with fire hoods to conform to regulations?

[LCR_Dave]

hi that dimmer should be fine then, people go for the low voltage lights mainly as its alot brighter and whiter light, holgen lamps tend to be abit yellow, osram do the best gu10 lamps they are about the whitest you will get, also low voltage is a bit more friendly when it comes to lamp replacement and tend to last longer, you only need hoods or fire rated light fittings if there is living accomodation above, if the cieling is stuffed with fibre glass you will need to create about an 18" space for the lights as they will over heat otherwise, reducing lamp life and causing the cable to get hot,
hope that helps abit more!

[smjxm09]

Thanks very much, you have both been a great help. There is a bedroom above the cinema room and the space is filled with fibreglass so I will get it removed.

I will take your advice Dave and go for the lights in the link and abandon the B&Q’s. The only issue is that my lighting bill has gone from £59 to over £200 including hoods and that does not include the bulbs

[smjxm09]

Originally Posted by LCR_Dave

you only need hoods or fire rated light fittings if there is living accomodation above

Dave is your statement on fire hoods correct? I have been looking at this IEE document about fire hoods and they say they are not required in the situation you describe as even with holes cut in the ceiling there is still 30 minutes of protection. http://www.iee.org/Publish/WireRegs/...n_ceilings.pdf

[LCR_Dave]

well current building regs say there must not be a break in the fire barrier if there is habitable space above it, this is achieved with downlights by either getting "fire rated" ones or using hoods, if your not under any kind of building inspection then to be honest i wouldnt bother providing you clear away enough fibre glass, not sure what there on about in that link, to my knowledge the current regs must comply with above, but the choice is yours!