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Why are Kino bulbs 2900?


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#1 andrew ward

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Posted 06 February 2013 - 06:36 PM

DUMB question im sure, but i was just changing tubes and realised i dont know
1) why Kino tubes come in 2900. Why not just 3200? Does 2900 offer something im missing?
2) why do Kino do 40w and 75w versions of the same tube? Wouldnt everyone want 75w?

Go ahead and tell me why im dumb.
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#2 David Mullen ASC

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Posted 06 February 2013 - 09:04 PM

Kino makes 3200K bulbs. The 2900K bulbs are a closer match to ordinary household tungsten lightbulbs though.
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#3 Matthew Parnell

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Posted 07 February 2013 - 07:20 AM

The 2900 kelvin variety was designed to be used in tv studios where the tungsten lamps were commonly dimmed to 80% to save on lamp life, and therefore generally ran at 2900 kelvin.

The 40w and 75w tubes are actually one and the same thing. The difference is in the labeling, which i believe changed over time to comply with different standards.

Kino ballasts in 4ft or HO mode overdrive 4ft 40w tubes at 75w, it's just Kinoflo tubes are designed to be overdriven to 75w.

The reason why the 75w tubes seem so much brighter is actually down to the fact that they generally have many more years of use than the later 75w tubes.
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#4 Matthew Parnell

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Posted 07 February 2013 - 07:27 AM

I meant to say, the 40e tubes have many more years of use.
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#5 andrew ward

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Posted 11 February 2013 - 10:27 PM

REALLY Matt?
Great! I was gonna buy all new 75w. Ill just keep the 40w. Sweet.
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#6 Matthew Parnell

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Posted 12 February 2013 - 06:51 AM

It's worth buying new ones while the dollar is low. The 40w tubes will be at least 10 years old and due for replacement. New tubes will give you another stop of output compared to the old tubes.
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#7 andrew ward

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Posted 14 February 2013 - 04:48 AM

Ah boo!
First you give and now you take!
I cant afford anything. Bugger.
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