Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

You can send an email to [email protected] if you have questions about how to use this forum.

Balancing whites - studio and shadow box

I am currently setting up my studio, and have everything in place, except the lighting. For my studio light I am planning to use two 9 watt LEDs (equals 2x63 watts), non-dimmable, 4000K. I know 5000-5200K is optimal, but I have a hard time finding bulbs with that temperature, and I think 4000K will be fine. 
On the shadowbox-front, however, things are more unclear. I know Mark says it is important to balance the intensity (not the color), of white paint, inside and outside the shadowbox. Still, I don't see why it would be a problem to paint a still life where the whites are darker than the whites on your palette under your studio light. The shadowbox would only act as a "door" into another room, with less bright lighting, and you would only have to tone down the whites for your highlights. (I do understand why the still-life light cannot be brighter than the studio light, as it is impossible to mix a color brighter than white). However, please correct me, if I'm wrong.

Out of all this, my question is: If I use two 63 watt bulbs for my studio light, do I have to use one (2x63=126) watt bulb for my shadowbox, to get the same brightness and achieve a white balance between the studio and the shadowbox? 
Also, will dimming an LED bulb change the Kelvin temperature?

Regards, Espen

Comments

  • 4000K is close, but 5000K is much better.  Here is a comparison I found:

    See how 3000K is yellow, and 6500K is blue.  The 5000K has the least deviation from white.  You can buy 5000K LED bulbs with CRI 95+ on Amazon, for example, for low prices, at least where I live.

    The color inside the shadow box is irrelevant, it could be a red bulb for all it matters.  It can be whatever you want, to achieve whichever mood or effect you wish.  It does not need to be bright, white or balanced (whatever that means).

    Outside the shadow box, you want your color checker and palette to be in the same light, which is 5000K and a bright as you find comfortable.  The brighter and whiter your light, the easier it will be for you to accurately observe and mix colors.  I have two 16w LED bulbs just behind my shoulder.

    I don't know about dimming.
    espnerhus
  • dencaldencal -
    edited September 18
    Espen

    Out of all this, my question is: If I use two 63 watt bulbs for my studio light, do I have to use one (2x63=126) watt bulb for my shadowbox, to get the same brightness and achieve a white balance between the studio and the shadowbox? 

    I understand you to mean that two nine watt LEDs are equivalent to two sixty three watt incandescents.
    Suggest you work in lumens to measure light. Watts are a measure of heat.
    Consider the distance from studio light to easel / palette and from shadow box light to still life.
    The first distance will be about five feet, the second distance about one and a half feet.

    The inverse square law describes how a point light source diminishes over a distance.
    Assume 11340 lumens. The easel will receive 567 lumens and the still life subject 5103 lumens.
    Suggest reducing shadow box light to 1200 lumens to achieve an intensity balance.

    Architects recommend about 1000 lumens for a detailed work surface.
    This suggests doubling studio power and proportionate increase for the shadow box.

    Try to use 5000k for both light sources.

    Yes a dimmer will change the LED color temperature.

    Denis


    espnerhus
Sign In or Register to comment.