From: "Dwight K. Elvey" 
To: atm{at}shore.net
Reply-To: "Dwight K. Elvey" 


Hi Guy
 If you put the slit side towards the mirror and the glass
side towards the light, it will not have any effect. Dwight


>From: "Guy Brandenburg" 
>
>Hmm. That is so cool. But is there any problem with the fact that the
>opposite sides of the slide are probably neither flat nor parallel?
>Guy Brandenburg
>
>Charles Mitchard wrote:
>>
>> Hi,
>> Peter Smiths (pjifl{at}bigpond.com.au) method of making a slit is easy.
>> rub a fine needle on glass or fine emery paper to get the finest point
>> possible.
>> paint a layer of black paint onto a microscope slide and before it dries
>> hard scribe a line.
>> It may take a few tries to get it right, ie. the paint at the right
>> stage of drying.
>> It then produces a very fine slit to shine the light source through.
>> Charles
>>
>>> Vladimir said:
>>>
>>> > I think that you can not make hair (wire) thinner or
thicker at will.
>>> > It is related to the slit width and what you are blocking
is slit image
>>> >  where it is sharpest ( thinnest). If you have fixed slit
and use to
>>> thin
>>> > hair, some light will spill around it and nulling the
zone will be less
>>> pronounced
>>> > ( contrast).
>>>
>>> Ahh, I see. I am constantly amazed at how much there is to learn.
>>>
>>> Now the question becomes how thin the slit should be, and how
to go about
>>> making it. I've read in the archives about methods for making
>>> pinholes, but
>>> not much for slits. A pinhole would work pretty much the same, should it
>>> not? And perhaps a pinhole would work better with a tester that has the
>>> source and hair moving together on an arc, because the slit would allow
>>> light to pass through on more axes.
>>>
>>> Probably I'll try a pinhole first, layering aluminum foil and driving a
>>> needle through the layers.
>>>
>>> Thanks!
>>> MTB
>>
>>
>> I just got lost in thought. It was unfamiliar territory.
>>
>>
>
>
>
>
>

--- BBBS/NT v4.01 Flag-4