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2. With the folded design we have greater focal lengths. 2500mm with a 2.5 powermate produces large image scale. This means our images of planets are bigger than any other scope. An SCT wins hands down here.
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Generally, that's true. It's much easier to get a larger image scale than an equivalent aperture newt. However the focal length is still ultimately dependant on the seeing. I've seen planetary/lunar images at approximately 10,000mm - with a large newt (like Wes Higgins 18" starmaster, or even Orion (Ed's) 18") it's still possible to achieve that focal length with a 5x powermate. But it really needs a night of perfect seeing to get any sharp and useful at that focal length.
So yes, for a 10" aperture if I wanted to do planetary imaging I'd probably get an SCT, but there are also drawbacks for widefield imaging, because of that exact reason - focal length. You just can't get a wide field, which is why you SCT guys get 80mm widefield scopes
Also for purely visual, there's nothing like a widefield view of the milky way through a newt.. I just don't get the same feel through an SCT because it's double the focal length.
Anywya each to their own, as long as the person looking for a scope to buy understands the pros and cons of each, they can make up their own mind.