A friend of mine is considering building a Dall-Kirkham system(12.5" F20). The primary is F3. It's my understanding that the spacing between the two elements is extremely critical. For those of you that might be familiar with this system, what kind of tolerences are necessary for optics of this variety to perform well? I know the Tak Mewlon is a DK. Is the primary mounted in a 9 or 18 point floation system? Thanks for any assistance. Mr. Darian Rachal
Darian R.
