I use flourescent lighting(since 1987). The 4' dual fixtures are hung about 3' over the layout, and about 1' in from the edge of the layout. This prevents 'shadows' from people viewing the layout. These are standard fixtures(Menards) with the cheapest lamps in them. I have had no 'fade' problems in this time. Think about it - How long do you have the lights on in the train room? Natural sunight would do more harm. If you are really worried about UV, there are color temp corrected lamps and even plastic UV shields to wrap your standard lamp tubes.
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
Depending how much room you have they should be 2 feet or more, above in order to not crowd the layout view. More than 4 feet above and they will start to not be that bright.
Use a valence to hide them .
There are different colors to use from bright white to cool blue.
here are some good ones
http://genet.gelighting.com/LightProducts/Dispatcher?REQUEST=CONSUMERSPECPAGE&PRODUCTCODE=14419
That is a tough question. Flourescents also emit UV, so you don't want them to be close to your delicate colours, if you must use flourescents at all. I don't know how long it takes for a person to detect the fading that longer time modelers complain about. I would guess that it might range from a few weeks with growing bulbs to many months with something engineered to be safer.
There are a couple of things to consider. One is that the further away the lighting is, the less intense it will be...inverse square law and all that stuff. On the other hand, having it resting on your highest head hairs might not be such a good idea if you use arms and tools from time-to-time.
Generally, it should be placed securely on your ceiling. If that is more than 5' above the layout surface, you may want to suspend it for a few inches...your choice, but leave room for swining arms and tools.
One other very important hint for you. I found that I had sufficient lighting, not overly generous, but sufficient, with my first layout. As time went on, though, I became frustrated with the lack of lateral lighting, light nearly parallel to the table top that was also behind me. I found that I could not rerail items, nor appreciate the valve gear motion of steamers going past me without an added pedestal lighting fixture aimed over my shoulder when I operated. So, for this latest iteration, I used track lighting and placed the tracks so that there was light aimed from above and from the side of the bench so that details under the running boards of steamers was bathed in light. WHAT A DIFFERENCE!! Now, when I stand facing either side of the square layout..I operate in a central pit... there is lots of light from the 5 halogen mini-fixtures above me, but also lots coming from just behind me. I suggest you consider this.
Guys, I Have a Question. Im going with Floresent Lights For The Layout.Now my Question is.For the light fixtures.How high should they be from the top of the layout? and is there differnt bulbs ,Im using daylight now.
Thanks Carl..