Telescope Reviews: New 6" F/8 ED Doublets from APM Telescopes

Hi Markus, do you guarantee that this 6" F8 OTA from you will have a certain maximum level of spherical correction? If so, what will it be? As I am wanting to upgrade to a very good planetary 'scope.

I have a Meade StarNavigator 102 (don't laugh!) and it splits the Double-Double (Epsilon Lyrae) easily, for example (2.3") but the 1st diffraction rings on those stars (E2) were quite easily visible at 200x, and I see that in the excellent Aberrator 3.0 Beta (did that guy ever update it?) that I seem to have about 1/4 wave optics (maybe 1/4 wave SA, maybe a little HSA, and a "small" amount of astigmatism maybe 1/5 wave, some of which seems to be coming from the diagonal).

I also see from Aberrator, and that if I had e.g. a 6" refractor with say 1/6 wave or better optics, I could see a LOT more detail on Jupiter with "decent" seeing conditions, compared with my 4" F8 Meade Achromatic refractor.

Is it possible that you could offer this 6" OTA with say 1/6 wave SA maximum guaranteed (and only say 1/8 wave of astigmatism at most), so that I could get excellent planetary performance, in which case how much would such an OTA cost from you?

As I get annoyed at manufacturers who cannot do excellent optics LOL (I wasn't referring to you!) as it makes all the difference with details on Jupiter (mushy view versus awesome view), and in my mind reputation should be more important than profits... Meade are you listening?!...

I am no longer willing to accept merely 1/4 wave ("Diffraction limited") optics as I need about 1/6 wave minimum. And I saw in a review once that a TeleVue 'scope had only 1/4 wave optics, which annoyed me, whereas I have never read of a TMB, Astro-Physics or Takahashi OTA which had worse than about 1/6 wave optics? Pity about the "enormous" price tags.

I also see that e.g. a 6" OTA with 1/6 wave optics or better just about completely removes that annoying 1st diffraction ring that I am seeing. At least Aberrator seems to think so?!

Also, is there an Alt-Az mount that I could mount this OTA on which has GOTO and tracking motors which have no vibrations at high powers (350x or so)? Since my mount's drive motors vibrate the objects at 200x !! Yeah I know, I bought an entry level 'scope LOL.

I am glad that you are going for a lightweight instrument, and that you are using a doublet for faster cool down times compared with a triplet.

Cheers,

Alistair G.