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You want to capture the (small) constellation Camelopardalis in one field ? As it is rather close to the South Celestial Pole no tracking needed anyway and visible anytime, anywhere in AU... LOL !
But serious:
Well, Short Dobsons / Newtons (f/5 or shorter) have a disadvantage of collimation duty, but with 200mm this is done within a minute. There are enough f/4 or f/5 Newton for under $800.
Unlike the ED/APOs of 100-120mm which sell for at least the double.
BUT: a refractor has usually better images and requires virtually no maintenance. And an f/6 120mm has a larger true field than a f/6 200mm.
And modern cameras have no problems with using high ASA values such as 1600 or more so aperture is for AP less an issue than visual.
And, what about a 2nd hand telephoto lens ? I frequently a Canon 1.8/85mm for AP with very nice results ! I pictured the entire Southern Cross more times in one field and stars till mag +12.
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