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Lack of contrast is frequently a problem in poorly constructed Newtonians.
Larger Maks on the market currently include:
- Saxon 8" f/12 Saxon,
- Skywatcher 180mm f/15 (I have one) from Andrews or Bintel,
- Questar's "Astro 7" or "Classic 7" (the Astro version is the better IMHO)
- the Meade 7" LX200, if you can find one secondhand.
- INTES MICRO - many to choose from.
- Cheap chinese 8" from Bosma, quality unknown.
- Orion UK have several 8" - 12".
Of the larger maks, ALL tend to suffer from tube currents and some form forced of ventilation is needed.
The Questar ones are far the best optically with consistently perfect diffraction disks, however there is a big premium to be paid for these; the benefit is you have a scope that performs as well as a 7" APO.
Second to Questar are INTES MICRO - consistently good quality optics and built like a russian tank.
The Skywatcher 180mm that I have is cheap rubbish - ie not great optically - it's resolution is barely better than my 4" refractor and it will not produce a distinct Airy disk. The orange C8 I had long ago was no better.
As for the rest... I suspect you take your chances.
Then you can consider of the Meade/Celestron SCT's in the range 8" - 11".
IMHO its a toss up between a Questar Astro 7, Intes Micro or a Meade 10" ACF. If cost is irrelevant, the Questar is exquisite and a lot more convenient but if you want the biggest bang per buck and the largest SCT that one person can reasonably set up, the Meade 10" ACF is the go.
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