|
Further flattening req'd?
I have been measuring through CCDInspector a complete series of FITS I recently took of NGC2467. This was using my Vixen FL102S using the dedicated Vixen FR, which reduces it to f/6.4.
The mean field curvature (compared over 20 subs) is consistently 7.0% - it's not FLAT, but pretty close.
That's acceptably flat to me, but is it worthwhile chasing the tail and getting it flatter? Anyone know of a decent FR/flattener that not only is moderately reductive (as opposed to the usual 0.8 like the Televue etc, which only bring my scope back to f/7.2) but flattening also?
|