8mm Forum: Lamp Brightness ST1200 , GS1200

This is topic Lamp Brightness ST1200 , GS1200 in forum 8mm Forum at 8mm Forum.

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Posted by Graham Ritchie (Member # 559) on March 20, 2006, 03:03 PM:

Here are a few facts from a old Movie Maker mag you may find of interest.
Lamp Brightness Foot Candles
Centre Brightness Average(BSI)
ST1200 D 1.3 lens low 18
high 24
ST1200HD 1.1 lens low 25 19
high 31 24
GS1200 1.1 lens low 27 22.5
high 39 32.5

Graham

Posted by Adrian Winchester (Member # 248) on March 21, 2006, 05:08 AM:

Can anyone explain why the latter two projectors have 2 figures for both low and high?

Posted by Jan Bister (Member # 332) on March 21, 2006, 06:56 PM:

From looking at the numbers, I think I know... the sets of two numbers are meant to be values for both the respective machine's lens and a standard 1:1.3 lens (as found in the ST-1200D) so you can compare the two.

It seems to make sense: the 1200D and 1200HD both output 18-19 at low lamp and 24 at high lamp. But in addition, the 1200HD using a 1.1 lens rather than a 1.3 lens outputs 25 low and 31 high.

And again, the GS1200 using a 1.3 lens (but a stronger lamp) manages to produce 22.5 low and 32.5 high, or 27 low and 39 high with the 1.0 lens.

I guess that puts my own 1200HD (with Schneider 1.2 lens) at somewhere around 21 low and 25-26 high (my own estimate). Hmm, not bad, but suddenly the GS1200 is looking mighty good. [Eek!]

Posted by Graham Ritchie (Member # 559) on March 21, 2006, 11:10 PM:

Hi Jan and Adrian sorry for the confusion when I typed it I had two columns spaced apart one for centre brightness the other average (BSI)when I posted it everything came together [Confused]

there was no way of fixing it until someone replied sorry again.
ST1200D 1.3 lens lamp on low centre brightness was 18 on high 24 ST1200HD 1.1 lens on low centre brightness 25 on high 31 with a average(BSI)low 19 high 24, GS1200 1.1 lens on low centre brightness 27 on high 39 average on low 22.5 high 32.5.I hope it comes out right this time [Smile]

Graham

Posted by Jan Bister (Member # 332) on March 22, 2006, 11:11 PM:

Ah, that's a bit different, but makes perfect sense.

Graham, you can always edit a post you just made, it's not necessary to wait for someone to add to the thread so you can reply to it. [Smile]

Posted by Winbert Hutahaean (Member # 58) on March 27, 2006, 04:50 AM:

Can someone explain what that number means.

And can someone too convert that number to lumens since this measurement is used nowadays.

thanks,

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