Saturday, January 20, 2007

Color-Balanced Lighting

One of my "daylight" fluorescent bulbs started flickering badly (annoyingly) as I was completing Simple Beauty the other day. I went to Home Depot to see if they had "Daylight" fluorescents at 48" — since the store I originally bought them from no longer stocked them. To my delight they not only had what I was looking for [Picture], but also screw-in style incandescent replacements that give off very bright light [Picture] (equivalent to a 100w light bulb in output) consuming only 27w — which is about 68% of what that little light in your oven consumes. And this bulb, which cost me $7 is guaranteed to last 9 years, and save me $73 in energy costs. How they figure that, I don't know, but I fell for it. Flipping over the packaging for the $6 Philips "Natural Sunshine" 48" tube (they also come in 24" and 18" at Home Depot) I could see that the color rating was 5000k. (Kelvin) Kelvin is a color temperature measurement; color accuracy can be seen best in the 5000k to 6500k range, with 6500k being similar to direct sunlight. By the way, Home Depot also sells 6500k "Daylight Deluxe" tubes also by Philips ($7 for 2!), but I elected to use the 5000k Natural Sunlight, presuming it would be more like indirect sunlight, and perhaps ever-so-slightly warmer. The package shows that on a 1 to 100 scale of the light providing the most accurate color perception, the 5000k Natural Sunshine bulbs were the most accurate, with a rating of 92 [Picture]. So now, with a combination of four 48" bulbs on my ceiling running above and behind me and parallel to the painting surface, plus my new 5000k palette light in an old Luxo [Picture] spring-arm lamp, I have good color-accurate lighting for painting. The addition of the color-balanced lamp near my palette has eliminated the problem of the palette seemingly in the dark as I mix, since it was noticeably farther from the ceiling lights. All the pictures taken for examples in this case were shot with the digital camera set to point-and-shoot (automatic) and absolutely no color corrections were made. I find them to be extremely, pleasingly accurate. Click here to see My Annotated Palette.

8 comments:

jeanie schlump said...

I have purchased color balanced as well as standard florescent bulbs like these and they DO last as long as advertised. I keep 2 on 24 hours a day on the landing & the hallway to my studio and they are wonderful. When the lights start to fail, they will both go out within the same day of eachother.

ParisBreakfasts said...

These look swell and I WILL get them.
But you shoot your paintings with them as well?

Lori said...

David is your liquin that dark in real life? It looks like its dark brown on my screen. The paints all look nice and bright.

I have those little fluorescent bulbs too, for several years now, one has blown but the rest are still going. I am using less electricity but its not showing on the cost, they keep raising the rates.

David R. Darrow said...

ParisBreakfasts: Yes, I have always (for the last 5 years) shot my paintings under daylight fluorescent.

The trick is to ALWAYS (just to be safe) set the White Balance manually before shooting the painting. With most digital cameras (sadly, not all) you can go into the manual shooting mode, and go to the white-balance settings, and manually measure or set the white balance by pointing the camera at a sheet of white paper IN the same lighting as your painting. This tells the camera's brains that "this is what neutral white" looks like, and will remove any color cast. This actually works fine in ANY kind of lighting, as long as the lighting is somewhat consistent. (You wouldn't want to shoot with a combination of daylight (blue) and incandescent (orange) as that would just confuse things.

Then, "bracket" the exposures... shoot under and over exposures, and pick the most accurate when you can see tthem large on your monitor.

Lori: My Liquin bottle is that dark... like an old medicine bottle. I have had this jar for 7 or 8 years. I am not aware if they come in clear bottles now. I haven't been paying attention. However, I must note that the Liquin inside the jar is aged, and has gelled and darkened to a dark amber anyway. It doesn't seem to have affected its usefulness, and has no appreciable affect on color mixing, though admittedly, when I do use Liquin, I use it primarily in the darks — especially in the under-painting.

Lori said...

I have some liquin thats almost used up, in the clear bottle, the liquin itself is brown too. Also works fine. I don't notice any darkening of any of the paint, if it did it would just give it a vintage-look which is fine with me. The new bottle I just got is also clear, the liquin is a bizarre light grey-purple color. I thought my old stuff was 7 or 8 years old too, yours must be really ancient! hehehe

Todd said...

Thanks for the information. I'll have to get some of those bulbs. Putting the blank piece of white paper in fron t of the camera is a great idea.

Takeyce said...

Wonderfully useful imfo (as always), David. Thanks for sharing!

Michael Chesley Johnson, PSA said...

Good tips on lighting, David. I've found that 5000K lamps -- what they call D50 lighting -- work well. D50 is used in the printing industry in viewing press sheets, since printed images have many colors to be evaluated.