Recently I've been comparing my Mewlon 210 to a Celestron 9.25. Here are a few of my not very scientific thoughts:
1. The C9.25 is very slightly brighter, no doubt because of its 1" aperture advantage.
2. The Mewlon has a darker background, an advantage when hunting dso's.
3. Stars seem tighter/smaller in Mewlon.
4. Dew is often a problem with the C-9.25, even with a dew shield. I've never had any dew problems while using the Mewlon.
5. Lack of corrector plate and open tube makes for faster cool down with the Mewlon.
6. Both ota's have mirror shift, but not a lot. The mewlon focuser is stiffer than that of the celestron.
7. Collimation is important on the C9.25 and HUGELY important on the Mewlon 210. With help of Bob Knob's, who is developing a set of Knobs for the Mewlon 210, I finally nailed collimation on my Mewlon. Now it displays a "snap to focus" quality heretofore lacking. But there is little room for error. Saturn views last night at 270x were very sharp. Binoviewer at 250x was hypnotic. I couldn't take my eyes away from the bv. But there is little room for error. The Mewlon has to be right on the money, collimation wise.
8. In summary, I find I prefer the Mewlon to the C9.25. There isn't that much difference in views, but I like its darker background and absence of dew problems. And of course it has that bulletproof Tak construction quality.
9. Needless to say, the M210 is much more expensive than a C9.25. Anyone opting for the C9.25 will not be disappointed at all. It's an excellent value with fine optics, tons of accessories, and a large user base. Strictly in dollar terms, it's the better choice. Eliminating price as a consideration, I'd go with the Mewlon 210.
10. Bob's Knobs sent me a set of M180 Knobs. They didn't work well with the M210 but they got me started. So I made a number of trips to the hardware store and developed a set that works extremely well. Bobs Knobs will incorporate my changes into a set he'll be selling for the M210. They greatly facilitate accurate collimation, and are a "must have" as far as I'm concerned. If you want to know how to make your own, let me know. It's very easy.
Rob Mackie
1. The C9.25 is very slightly brighter, no doubt because of its 1" aperture advantage.
2. The Mewlon has a darker background, an advantage when hunting dso's.
3. Stars seem tighter/smaller in Mewlon.
4. Dew is often a problem with the C-9.25, even with a dew shield. I've never had any dew problems while using the Mewlon.
5. Lack of corrector plate and open tube makes for faster cool down with the Mewlon.
6. Both ota's have mirror shift, but not a lot. The mewlon focuser is stiffer than that of the celestron.
7. Collimation is important on the C9.25 and HUGELY important on the Mewlon 210. With help of Bob Knob's, who is developing a set of Knobs for the Mewlon 210, I finally nailed collimation on my Mewlon. Now it displays a "snap to focus" quality heretofore lacking. But there is little room for error. Saturn views last night at 270x were very sharp. Binoviewer at 250x was hypnotic. I couldn't take my eyes away from the bv. But there is little room for error. The Mewlon has to be right on the money, collimation wise.
8. In summary, I find I prefer the Mewlon to the C9.25. There isn't that much difference in views, but I like its darker background and absence of dew problems. And of course it has that bulletproof Tak construction quality.
9. Needless to say, the M210 is much more expensive than a C9.25. Anyone opting for the C9.25 will not be disappointed at all. It's an excellent value with fine optics, tons of accessories, and a large user base. Strictly in dollar terms, it's the better choice. Eliminating price as a consideration, I'd go with the Mewlon 210.
10. Bob's Knobs sent me a set of M180 Knobs. They didn't work well with the M210 but they got me started. So I made a number of trips to the hardware store and developed a set that works extremely well. Bobs Knobs will incorporate my changes into a set he'll be selling for the M210. They greatly facilitate accurate collimation, and are a "must have" as far as I'm concerned. If you want to know how to make your own, let me know. It's very easy.
Rob Mackie
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