[ATM] Dark finish for a telescope tube

[hermit]

Dominic-Luc Webb wrote:
> On Tue, 26 Sep 2006, hermit wrote:
>
>   
>> A densitometer is a highly precision instrument for measuring
>> reflectivity.  Phil Davis in his book does give a method for converting
>> a spot meter for use.  The densitometer uses a fairly bright light.
>>     
>
> Labs sometimes use common scanners for densitometry.
>
> Dominic-Luc Webb
>
>   
Tried that and failed miserably.  Could have been my scanner though. 
Any links?

Ken Lowther