Affordable Triplet Refractors?
Tuesday, 31 May 2011 | Admin
We are often asked to source and supply 'affordable' triplet refractor telescopes. It would be easy enough, FLO has access to them, so why are we not doing so?From a purely marketing point-of-view cheap high quality triplets are the holy grail, but triplets are considerably more difficult to manufacture to a high standard than doublets. They are expensive for a reason.
In an attempt to get a handle on a complex subject people focus on whether the design features FPL51 or FPL53 (or equivalent) glass and whether it is a doublet or triplet. But, not all FPL51/53 glass is equal and it is used only for the ED element, of equal importance is the quality and finish of the mating elements.
Consider also the lens cell - the metal structure that holds the elements in alignment. A considerable amount of thought, expertise and manufacturing know-how is necessary to produce a precise and robust cell that maintains alignment and doesn't 'pinch' the optics on a cold winters night. Some big names have tried and failed and a poorly designed cell will ruin an otherwise excellent optic.
When modern materials and manufacturing processes enable mass production of affordable triplet refractors with consistently high optical performance (not just the first batch, or the one supplied for product reviews) then we will offer them here at FLO. Until then we will sit tight and monitor the situation.
Hope that helps.