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Daylight Bulbs

4th April 2007

Hi,

I'm looking into daylight bulbs or close to daylight. They're for use in practicals in a shot where we'll take someone from exterior to interior.

The plan was originally to use 60 and 100 watt tungsten bulbs. That was before bringing someone from outside in was an issue. As far as I remember daylights bulbs are only about 30-40% as efficient as tungsten’s.

This is for shooting in Ireland so an Irish or UK suggestion would be especially helpful.

Ruairi O'Brien,
Cameraman,
Ireland.


> I'm looking into daylight bulbs or close to daylight....

Try these med. base fluorescents designed for people with
seasonal affective disorder :

http://www.ottlite.com/productdetail.asp?product_id=127

The Ott lights have the highest CRI of any of the fluorescent type replacement bulbs that I'm familiar with.

Jessica Gallant
Los Angeles based Director of Photography
West Coast Systems Administrator, Cinematography Mailing List
https://cinematography.net/


Ruairi O'Brien wrote :

>>I'm looking into daylight bulbs or close to daylight. They're for use in >>practicals in a shot where we'll take someone from exterior to interior.

If your talking about daylight balanced (4800 K - blue) incandescent photofloods, they're a whole light brighter than 60 or 100 watt household bulbs.

You might want to investigate some of the newer spiral compact fluorescent (CFL) bulbs designed to replace household bulbs. Some of these bulbs (Cool white and daylight) have very high CRI's and if the bulbs are used in shaded fixtures they might be just fine for your purposes.

Brian Heller
IA 600 DP


Lowell Lights has recently introduced a cheap fixture that uses daylight-balanced compact fluorescent bulbs with an ordinary lightbulb base. I thought they could be useful in things like Chinese Lanterns, practicals, etc. and they don't draw the same power or create the same amount of heat as a blue photoflood (4800K), which generally come in 250w and 500w.

Here is the link to the 5500K flo bulb used in the Lowell Ego light :

http://www.lowelego.com/lamp_info.html

David Mullen, ASC
Los Angeles


I had a look around and found these

http://www.bltdirect.com/products.php?cat=88

You'd need to test them, however they're not as powerful a photoflood -150 watt max.

They also seem to have quite a few other interesting lamps on their site.

Brian Drysdale
DP & Steadicam
Belfast


David Mullen writes :

>>and they don't draw the same power or create the same amount of >>heat as a blue photoflood (4800K),

I'd like to add : These photofloods are not 4800K when new (closer to 4400K), drop in colour temp rather quickly during use, and last an average of 6 hours before burnout.

Cliff Hancuff
Washington DC


Cliff Hancuff wrote:

>>I'd like to add: These photofloods are not 4800K when new (closer to >>4400K), drop in colour temp rather quickly during use, and last an >>average of 6 hours before burnout.

Like any incandescent bulb, they are sensitive to voltage. They are rated 4800K when used with 120v, but very few locations have the full 120.

If you have access to a voltage boosting Variac or other means of increasing the voltage, you can dramatically increase the light output and raise the colour temp of any incandescent bulb -- 150 volts will give you more than twice the light output, and a 300k boost.

Of course, the rated life also drops dramatically, but it might get you out of a tight spot.

Brian Heller
IA 600 DP



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