A few years ago I needed to increase the light in a kitchen lit by an overhead fluorescent fixture. As I found it, it had two 4-foot T8 735 tubes and an "energy-saving" (read: light-reducing) instant-start ballast. To make it brighter without the hassle and expense of replacing the lamp fixture, I replaced the ballast with the highest-overdriving ballast I could find that could drive a pair of F32 T8's. After some online research, I wound up buying a Philips Advance IOP3P32HL90CSC (a.k.a. IOP3P32HL90CSC3SI , sometimes with several hyphens inserted for readability). It can drive either 2 or 3 bulbs, but overdrives more when used with 2 bulbs. This was a few years ago, there might be something better now, but 1.37 ballast factor replacing a 0.87 or something makes a substantial improvement in brightness. I also upped the brightness slightly by replacing the TL735 bulbs with TL830 or TL835's which are slightly brighter and have better color rendering, which the eye perceives as adding brightness. Re: Philips TL930/TL950 :I've used both the Philips TL930 (95CRI) and TL950 (98CRI) 4-foot tubes., which fortunately I was able to buy two at a time from the local retailer. The TL950s illuminated my kitchen; the 930s went into a basement rec room where they match the color temperature of halogen downlights. The TL950s won't blow you away upon first turning them on - they look like typical cool/sunlight fluorescents at first. Its just that the different colors really pop out well and cleanly and the colors jump out at you rather than being dulled. The kitchen there has no windows, and in the morning sunlight, I noticed the ambient light from the windows across the apartment matched the TL950 light in the kitchen perfectly. If I take pictures with a film camera loaded with standard color film (daylight-balanced), pictures taken with available light indoors under typical "cool white" fluorescents lend an awful greenish cast to everything, but those shot under TL950s had perfect color. That says boatloads about the TL950's color accuracy. As for the lower lumen output, I again compensated by overdriving them by about 25%. I needed a rapid-start ballast for these fixtures, and went with a GE/Motorola ballast that overdrives a pair of F32 T8's with a ballast factor of about 1.20 IIRC, not as bright as the Philips I mentioned above but adequate for my needs here, plus I needed rapid-start rather than instant-start for this application. There are (were?) 2700K, 3500K, 4100K, and 6500K versions of these bulbs sold in Europe. Too bad they aren't sold in North America.

I just came across this in the back of a Keichler lighting catalog. Hope it is useful to you. The question was, How much light do I need in an area to light it properly? A - Multiply the length times the width of the room. Then, multiply that number times 1.5. That give you the amount of wattage you neeed to light the room properly for general illumination. Example: A room is 12 ft. x 16 ft. (12x16 = 192) Then multiply 192 x 1.5 = 288 watts. For specific task lighting in areas where stronger light is needed, multiply the area's square footage by 2.5 rather than 1.5 to find the needed wattage. These same rules apply to every room or area in your home.

I think that it has been my second CFL twisty that was in a table lamp on my desk that shone on that and the computer desk. It's been going off occasionally lately and for a while when I twisted it in the socket it would light again, but soon it'd only flash for a second or so, then go out again. So it looks as though it's had the biscuit. It's been three or four years, I think - but many of my incandescents lasted for quite a while and they cost a great deal less. I think that I've heard that the CFLs work best when they're on for a long time, but not so well when they're turned off and on quite a lot. If one were to leave them on for many hours on end prior to the next need ... when not using them, not much saving of power there. Haven't tried LED yet. ole joyful

hk-san-diego, Thanks for the information. I appreciate it. Your information about the percentage dimablity for each type of bulb is VERY important. Regarding the 1.5 calculation: My kitchen is 10 by 14 = 140 sq ft x 1.5= 210 watts. I assume that is florescent. Times 4 for an incandescent wattage equivalent or 840 watts. Currently I am using about 160 watts florescent but getting 12800-14000 lumens. To me, lumens is the important factor, because I have seen 65watt equivalent fluorescents range from 550 to 750 lumens. As you mentioned there are other factors. How much light from a bulb gets lost in the fixture or on the ceiling, etc. The reflector lights seem more efficient and effective since the light is focused down. I feel that a 65 watt equivalent florescent reflector might give the same light below as a 100 watt equivalent spiral clf, maybe. Light color is important to me. GE has a 4ft tube florescent that I used for years that is for kitchen and bath. There is one color: 3000k. I like the color and it does look good in my kitchen. Problem is that when they came out with their dimmable 65watt equivalent reflector it is only in 2700k. I cannot find a dimmable 65watt 3000k reflector. I probably will end up with 7 - 65watts equivalent, 3000k, non-dimmable split on 2 switches to get a reduced light level when needed. What you said about the 60% dimming (without problems) makes that solution easier. Thanks again, Bob