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I think it is easy to become a victim of false economy and we overlook that a Dobsonian mount is a huge comprise..its invention was in times when astronomy gear was unaffordable as building your gear was perhaps the only way most folk could enjoy the hobby. So one would make/grind the mirrors, build the tube, construct the spider for the secondary mirror...the whole thing so an eye piece was perhaps the only part of the set up one needed to buy...and the Dobsonian mount was just another way of making things affordable...it replaced an expensive mount...even a non equatorial mount was very expensive..the Dobsonian worked and anyone could build one...these days they are offered to make a cheap package and they are OK however everything you observe is moving and so with a Dobsonian you must move it to keep the object in the field of view...leave the set up for a nature break or a cuppa..whatever ..and your object has to be located again..it can be done sure but really you do need that hassle...to me an equatorial mount is a necessity and they are relatively cheap these days and most important have the system to have the mount " connected" to the sky by having it correctly aligned to the Celestial South Pole and then you have the magic of goto and tracking...so instead of wobbling around with a Dobsonian mount with say an EQ5 equatorial mount you either enter the objects co ordinates ( unlikey as everything is in the mounts data base) or simply select the object you wish to observe and the mount takes you there and tracks it..come back in 10 minutes it will still be in the field of view. Folk tend to think that you dont need an equatorial mount because a Dobsonian will work...it will but only just...dont be fooled to think as one wont be doing photography you have no need for a goto equatorial mount...if you never do photography visual observing with an equatorial mount is in my view the sensible way to go.
Again the first thing to buy in my view is your mount ... And think of this.. in every case your magnification is limited by how steady your mount is...you can go way higher in magnification using a good equatorial mount...because it is steady ...so simple but people overlook that fact.
Now I expect folk will try to argue that is not so but just think it thru..what I say is the truth.
When you go big the equatorial mount gets expensive but a EQ5 will take an eight inch both for visual and photos and at the price really makes the choice super easy.
Alex
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