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Messages 61 to 70 of 316 (Total: 316) First | Prev | Next | Last
Subject 
Author 
Date 
Re: Using a flash for testing.  
John Hannon  13:16 8 Nov 07 
Re: Using a flash for testing.  
Jorge Gasteazoro.   19:05 8 Nov 07 
Re: Using a flash for testing.  
Ben Wilbur  15:13 8 Nov 07 
Re: Using a flash for testing.  
Don Bryant  19:22 25 Dec 07 
Re: Using a flash for testing.  
Jorge Gasteazoro.   20:19 25 Dec 07 
Re: Using a flash for testing.  
Don Bryant  16:15 27 Dec 07 
Re: Using a flash for testing.  
Barry Wilkinson  3:03 28 Dec 07 
If my ramblings are too off topic, please delete them Mods.

I'm sure that the flash output could be made adjustable. How repeatable could only be found by experiment. Unfortunately I don't have access to the electronic lab equipment I once had to try this.

As I understand it, the flash circuitry charges a capacitor to a pre-defined level. The stored energy in the capacitor is then 'dumped' into the flash tube. I assume that this energy can be adjusted by altering the charge level or the time to discharge the capacitor?

I have been considering making a 'film exposure box' but using tri-colour LED's instead of flash. I understand that the output of these can be controlled using Pulse Width Modulation techniques. Chips are available for this purpose.

Using flash or LED's still has leaves the problem of getting even illumination across the exposure surface. I am considering using the same kind of light mixer that my enlarger uses. This is a simple box lined with polystyrene. This would sit below a perspex diffuser. Any idea's welcomed. I think this would work equally well with flash or LED's?

Any electronics persons out there?


Barry
 
Re: Using a flash for testing.  
Steve Nicholls  15:59 28 Dec 07 
Re: Using a flash for testing.  
Barry Wilkinson  2:11 29 Dec 07 
Re: Using a flash for testing.  
Steve Nicholls  2:49 29 Dec 07 


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