Granted, the SV90T will have a crisper looking image than the ACF on planetary details, but that's a consequence of the type of optics being used. However, if you want resolution and light gathering capacity also, you won't go past the ACF....it wins hands down. Especially if you want those nice looking nebula and galaxy shots, your 8" will out perform the refractors any day. Small refractors are great for wide field shots and planetary imaging, but try and get a close up of some faint PN or dim galaxy and see what happens. That's why you see the big guns taking piccies through different setups...they have their wide field and ultra crisp small refractors and a big lightbucket.
Just like a racing car driver...they don't use their 4-6 cylinder putt-putts to drive around Bathurst, they use their mongrel-sized V8's. The putt-putts are for town
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