Aperture, aperture, 80mm?

Why are 80mm apo scopes so popular?

If aperture is king, why not use a 120mm achromat at low power and stop it down to say 90mm for higher power?

Are apos at 80mm so good that aperture does not rule?

What am I missing?

1. Wide-field Photography. APOs rule here.
2. Extreme portability. Airline portable, in fact.
3. Lust factor.

I'm sure there are others. And your example of a 90mm achromat will not perform as well as an 80mm Apo at high powers on planets, etc.

I am fairly new to telescope astronomy,having used scopes now for just over a year. I was a pure visual stargazer for years, a short stint with binos then back to eyes.

I started with an 8 dob and a 6 Eq mounted hardin Newt, then moved to a 102mm Orion mak on a camera tripod. Next came a Tele vue Pronto.

All had good and bad points, I found that the pronto was the scope I used most often and recived the most joy from. Its only fault was its size ( too small)!.

So moving up to an 80mm Ed scope as a main scope has been the perfect choice for me. Easy to set up,affordable, and great views of wide swaths of sky.

I do plan on picking up another scope or two and am currently looking for a smaller Newt and later a nice 4 inch apo for planets.