Ballasts... Do They Matter?

[sothoth]

Any lighting experts out there? If so, I'm wondering how much of a difference the ballast can make in producing the desired wavelength of a lamp. For example, if I have a fixture with 2x 95W VHO lamps (~36" long), one actinic, one 10000K, would I see any change in the spectral output of the lamps depending on what ballast I use? I realize this is tough to answer. I guess the easy way to ask is whether the ballast has a major/minor/non-existant role in the spectral output of the lamps. Thanks!

 

[sothoth]

Actually, can one just use a digital camera to test the spectral output? I think most of them give a color histogram. I'm not a physicist, but that seems to make sense to me. Thoughts?

 

[Adrinal]

if it gives the numbers of intensity between x and x color-temp... you could probably figure something out. I couldn't imagin doing it though.

 

[SkiFletch]

Well, there is SOME difference, but rarely is it a significant difference. And you won't change the type of wavelengths that the bulbs output (that's governed by the phosphors used), but you may increase or decrease it's intensity.

 

[Rooster]

The ballast has ZERO effect on spectra..... thats all down to the gas and coatings within the tube(s)

 

[jeasko]

Rooster have to agree with ski on this one, if you have a multi purpose ballast that will run a number of different type of lamps the output may not be the same as a ballast that is just dedicated to one type (will be a different tollerance in the output for exaple to within 1% or 2%), this could affect the output v, the intensity would then be altered and a slight diffference of colour output (probably not noticable to the human eye but a difference none the less), the colour could be affected by the ignition source of the lamp, ie not burning it intense enough. so kind of both right here but if your being precise there could be a diiference in reality you would never notice one.

Also dont be under any illusion that a histogram will give you any good advice as the pixels on a digi cam would just be burnt and show nothing of use on a histogram.