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Question: Seems nice but I'm concerned about the focusing mechanism. Is it durable? Could a normal focuser be fitted to this scope? Thanks
Document: This is my first telescope and I'm really loving it.For now I was able to see the Moon in detail and could observe Jupiter like a striped sphere and Mars like a small and red sphere, but it was a really nice experience to see in real life. I also watched some constellations like Orion, Crux, Scorpio and many bright stars like Sirius.This telescope is really portable, easy do handle and easy to set.
Takes a couple of seconds to completely settle after using the focuser. No more!Very impressed with this go to scope. Easy, fun, and just pleased for the value of this starmax 90.Would highly recommend. This is my first scope and not disappointed at all with it. A great buy!Did not think I would actually see what I could with it because I am new with this hobby!
The telescope is light, nice, easy to handle but I had a problem with the 10mm eyepiece, I could not get it to focus, I called Orion Tech and they tried to help me but I could not get it to focus on the moon ...  the tech said that might be because of the high magnification... but what's the use of the high magnification if I can't use it to look at the moon?
I purchased the StarMax 90mm to serve two purposes: introduce me to astronomy and serve as a super telephoto lens for my cameras. It seems to do both nicely. Weather conditions have not been very favorable, but I have enjoyed some nice views of the moon. I've actually used it more for terrestrial viewing and photography so far. For that purpose, it's light weight, easily portable and the images are sharp. The top of a church steeple 3/4 of a mile away fills the eyepiece.
I bought this telescope for my son hoping to fuel his passion for astronomy. Turns out this little telescope brings the entire family together like nothing else. Well built. Good fit and finish. Setup is a snap. Afterward we spent about 30 minutes becoming familiar with the scope looking at terrestrial objects during the day. Later that night we saw amazing views of the Moon and Jupiter. Yes, we could clearly see the cloud rings on Jupiter!
Very portable and has a 1250mm focal length which great for such a relatively short scope. That is actually what made my mind up on purchasing this scope over the others. The Mak-Cas design allows you to get a much longer focal length that you would with a normal reflector and still provides great images.
When viewing the Orion Nebula I was able to see a decent amount of nebulosity and some very faint level of detail, but of course, with its 90mm aperture, you can't expect to be able to see as much as you would with a larger scope. But the Starmax still showed enough of the nebula for it to be an good view. The stars clusters, M41 and M50, both showed a nice view with many stars visible with the use of the low power eyepiece.
The only negative I have is that because of the long focal length of this scope wide field of view is not really possible. I knew this going in so I am in no way disappointed, but still felt I should mention it. I mostly got this for the moon and planets, so like I said not really even a negative for me. Thanks and I hope this is helpful.
I recieved  the starmax a few days ago....was well packaged. The OTA is of high quality and the eyepieces that are supplied are marked orion plossls. The catalog says 10mm and 25 kellners....Anyway they seem good quality. The small dobsonian style mount is ok for the job ( I mounted the whole setup on an old bogen photo tripod)because the starmax is so lt. wt. ( you could probably mount a short tube 80 on it too.)
I bought this for my daughter. She's just getting into star/moon gazing. Nice and small with decent light gathering power. I wish the offered a carrying case.
Answer: I am very impressed with the focusing mechanism. It feels very quality and easy to fine tune to get a beautifully focused image to the most magnification the scope or sky conditions allow on any given night. It simply has not let me down in the least. Now can it be replaced or changed out? I am not sure 100% but doubt it. It is a knob the comes out the back of the telescope and isn't connected directly to the eyepiece like a crayford focuser in which you could just change it out. It seems to me to be a special focuser mechanism for this particular telescope. For me it hasn't at all been a thought in wanting to change it. You'd benefit more from buying a nicer diagonal or eyepieces. I doubt you will be disappointed with the focuser. I am going to try and attach a picture of the back of the telescope so you can see what I am trying to describe.