[skysurfer]

I have the Televue Genesis and for me it is a good (travel) scope. Many discussions on CloudyNights are about : "Does modern (semi-)apos perform better than the 30 year old Genesis ? " Or "is the Genesis an APO ?".

I would say: Yes and No.

Yes: it corrects colors better than achromats because of the rear-end Petzval elements and even at high power, only slight hints to violet halos are visible @ 200x and high-contrast targets.

No: According to Wikipedia an Apo is a *three* element objective putting three wavelengths in one point. An objective which corrects for only two wavelengts is an achromat as the Genesis does.

So some WO FLT triplets are apos, but even the NP-101 which is an improvement over the Genesis (better glasses used) and probably the best 10cm refractor in the market beside the Tak FSQ-105 but has still the same Petzval design and is just an achro but a VERY GOOD one.

What are your ideas ?