I Lens

[Tom Droege <tdroege2@earthlink.net>]

We were working on installing the Dec drive fix and Dan pointed to the I 
lens and said "There seems to be a piece of tape in the lens".  I looked 
and sure enough it looked like there was a piece of scotch tape stuck to 
the inside of the lens.

Later I opened up the lens to remove the "tape".  It turned out to be a 
fractured second lens element.  The second lens is in a cell and got 
squished by the Chicago winter, I guess.  I thought this lens would be safe 
since the lens cell is not so thick.  But it was crushed.

Now I don't know if this is the cause of the I lens always being poorer in 
focus than the V lens, but I doubt it.  Probably just some distortion of 
the flat would be the result.   I estimate the total "crack" area to be 1/2 
sq in.  But who knows how much the lens surfaces are disturbed by the stress.

The Dec. drive fix looks like it will work great.  But I still have to try 
to point at stars and see how well it can repeat.  No more clamp is 
required.  Basically I made a pully the diameter of the brake disk and put 
a cable around it to the dec drive motor.  Amazingly all the pieces fit as 
planned.

Tom