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Hi Stephen,
IMO the Protostar quartz secondaries are the best you can get. They are exceptional. The largest size you can get in these is 2.6" which should be the right size for your 14" scope. Whilst they are only rated as 1/10th wave minimum guaranteed, they are way better than this. The 2.6" one I have in my 14" SDM with Zambuto primary came with a zygo certificate at 1/40th of a wave. In addition the protostar quartz secondaries have a minimum scratch dig of 10/5 which is extremely smooth, as they are designed for laser applications. This smoothness helps reduce scatter. At $US 265 you get what you pay for. The Antares 1/30th wave secondaries as mentioned by Trevor are also very good. You wont go wrong with either. Don't confuse the 1/10th wave secondaries from Antares with the 1/10th wave minimum rating from Protostar. If you need a spider also the heated secondary holders and spider from Protostar are expensive and outstanding , with a long wait time, but worth waiting for IMO.
As a matter of interest who made the primary and how do you know its 1/25th of a wave? How was it tested? There are about 6 people on the planet capable of producing 14" mirrors of that quality consistently. Mark Suchting is one and Carl Zambuto is another. Or is that 1/25th of a wave RMS (.040), which is about .9 strehl.
Cheers,
John B
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