'cool' temperature lights

I need to buy or make some cool lights (as close to daylight/5500K as

I can get, & that are a reasonable weight,are portable, and give a

decent amount of f-stop/shutter speed - I cannot use flash/strobe and

tungsten/halogen lights are too hot. Lowel make a unit called

Scandles but it's only 200w and I am sure you cant get much of an

exposure from them. Can anyone share their experience?

thanks

Frank

The Scandles look interesting although expensive. Don't iunder rate the output though. It may be 200W but according to the literature it is apparently equivalent to 500-750W incadescent ...

Frank,

 

Just curious..why can't you use flash ?

When you say tungsten/halogen are too hot, are you talking about

color temperature or thermal temperature? I assume thermal, because

the term usually used for a low color temperature is "warm", not "hot". (To add to the confusion, photographers use the term "warm"

to indicate a low temperature black body radiator, and "cool"

to indicate a high temperature black body.)

<p>

Anyway, the electrical wattage rating of a light is an almost perfect

indicator of the amount of (thermal) heat it will throw off. So if

your objection to a 500W photoflood is that it's too hot, you're

not going to be able to use much more than that 200W Lowel light

you were looking at.

<p>

If the problem is color temperature, you can use color correcting

filters either over your lights or your lens, at a cost of some

light output.

<p>

I, too, am curious why you can't use flash. That's the usual

convenient solution to the problem.

I am using the term hot in a thermal sense, not as in the col temperature which can be solved with filters or the appropriate film. Although it would be nice to have my cake and eat it too, and have the thermal temperature cold and also the col temperature cold (daylight)

:-)

I cant use flash/strobe because for this particular project the portrait subjects are sensitive to the 'flashing'and it spoils the mood. Also, I prefer to see the light that I'm going to get as you can with constant or ambient light. A strobe/flash unit's modelling light doesn't 'do it' for me and I havent got the capability to use polaroids for light testing.

Rent some Kino-Flow daylight balanced flourescent lamps. There are many versions,

so check them out first. Some are quite large and some are tiny. They are not the

lightest in weight, but they are not hot when used. Most are dimable with no change

in color temperature. If you need a "hard" light, rent a small HMI lamp.

 

As for f/stop-shuttter speed---tell your subject to hold still, you won't have a choice

without really bright lights or strobes.

I just bought a bunch of 48 inch "shoplights" from the hardware store - the units are all wired up and ready to plug in. A bank of 10 units would give a 4 foot x 4 foot light bank - all connected to a good power bar. With 2 tubes in each unit at 40W per tube = 80W, 10 units would draw 800watts which should be ok for a household circuit. I found Philips "natural sunshine" 48 inch tubes rated at 5000K and 92 CRI. What do you all think of this plan?

<i>I found Philips "natural sunshine" 48 inch tubes rated at 5000K and 92 CRI. What

do you all think of this plan?</i><p>

 

I think they will photograph green! They may look like "natural sunshine" but they

ain't.<p>

 

I think you should shoot a test or borrow a '3 color' color meter to check before

making this plunge.<p>

 

Are you shooting digital? If so, you can correct for the green in the RAW conversion or

the camera white balance.<p>

 

Shooting film? Shoot daylight film with a 30cc magenta filter over the lens, but test

first!<p>

 

If you are shooting mixing your lights with natural daylight, you will have to put the

magenta filters over the flourescents lamps to match the daylight color.<p>

 

So Frank, shoot your tests and report back please.<p>

 

-bruce

a minolta col temp meter rates it at 5010K and recommends the use of an 82A and 5M filters to bring it up to Daylight balance.This is minimal filtering.

<i>a minolta col temp meter rates it at 5010K and recommends the use of an 82A

and 5M filters to bring it up to Daylight balance.This is minimal filtering.</i><p>

 

Thanks for the info Frank. That's good to know!<p>

 

With that little filtration, I wouldn't bother correcting at the camera.