Re: [ATM] ATM Digest, Vol 50, Issue 3

[ken scharf <wa2mze@bellsouth.net>]

atm-request@atmlist.net wrote:
  Date: Sat, 02 Feb 2008 16:48:45 -0500
> From: Mark Holm <markholm@verizon.net>
> Subject: Re: [ATM] Surplus Shed 90mm F10 objective
> To: 'ATM' <atm@atmlist.net>
> Message-ID: <47A4E53D.2070108@verizon.net>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> 
> Has the 3" coupler a large enough ID to not vignette the 90mm objective?  90mm is 3.54 inch.  I don't recall that sched
> 40 pipe is .25 inch thick.
> 

The ID of the coupler is just a hair over 3.5" as per my calipers.  The
wall thickness might have been more than .25", but I had to shave down 
the outside of the coupler to fit it inside the 4" tube and the inside 
lip of the lens cell.  If there is any vignetting, it is a stop down of 
less than 1 or 2 mm of the lens diameter.
_______________________________________________
ATM mailing list http://www.atmlist.net/