From: Guy Brandenburg 
To: J&S 
CC:  atm{at}shore.net
Reply-To: Guy Brandenburg 


Thanks for the information. It is amazing that all that stuff is there, and
I had forgotten even having ever seen it at all. Looks like I repeated,
with some changes, what others have done.

That being said, I still can't see the friggin' interference fringes with
an ALUMINIZED mirror with my 5461 Angstrom source (using theatrical
lighting gels to filter out everything else from a fluorescent tube) and my
reference flat. The nylon mesh from support-top stockings didn't work
- unless you count seeing the strands of nylon! My setup works fine with
un-aluminized pieces of plate glass.

I will improve my light box somewhat by roughening one side of the glass,
and will attempt to see what happens if I put a very, very thin film of oil
in between the two flats. I will also attempt to see what happens if I use
a red filter to view the fringes...

I was not able to see Dave's images - probably took up too much room and
they expired, or something. Dave Sleeter, are you out there?

Guy

J&S wrote:
> Hi Guys,
>      Dave Sleeter (are you still out there Dave?) did a good aggressive
> investigation into solving the "seeing contrasty fringes on aluminized
> surfaces" issue in the January - May 2002 timeframe, and came up with what
> looks like the final solution, complete with photos and sources.
>      Check the archives. Do a search on "photographing
fringes" to get to
> it, or just search May 2002.
>      Here is a snip from one e-mail he posted. There is much more
> information in previous posts he made.
>
> SNIP-----------------------
>  I decided to try a 100 watt
> UNCOATED Mercury lamp and a Roscolux #89 moss green filter.
> ...For viewing fringes on aluminized optical
> flats, this combination of lamp and filter seems to work well.
> UNSNIP------------------
>
>      There are some links to photos he posted too. I didn't check to see if
> they still work, but I do remember they looked great - much better than I've
> seen elsewhere.
>      Good job Dave!
>
> - Jim S.
>
>
>


--
Guy Brandenburg
Washington DC, USA
http://home.earthlink.net/~gfbranden/GFB_Home_Page.html

--- BBBS/NT v4.01 Flag-5