[mental4astro (Alexander)]

Hey all,

I finally got a chance to give my brand new 9mm a thrash.

I chose my 8" f/4 scope for this knowing that if a particular f/ratio would show any short comings, an f/4 would, making sure it was as well collimated as possible. This scope/EP combo gives 90X neat.

1: Jupiter was first of the rank. Oh, how nice. Nice banding and all four Gallilean moons on show. Moving the moons to the edge of the FOV, the very last 5% started to show the effects of coma, and a tiny amount of astigmatism right on the very edge. I doubt this would be obvious in any other scope of a slower f/ratio. It was only noticeable by really looking for it. Diffraction spikes from the spider were visible only radiating of the bright planet.

2: M7 was low in the western sky, depriving me of its full potential. Still, WOW, nice bright stars all the way across the FOV.

3: 47Tuc- now we're talking. BAM! So many stars! Spectacular resolution, and at 90X nearly the full extension of the GC filled the FOV. I pulled out my 2X barlow, man-oh-man! Still pin-point stars, and the entire FOV totally packed with the massive cluster. The effects of coma were not noticeable with the barlow.

4: NGC 253. As I had suspected, Sydney's sky has gone to the dogs big time in only one year. I had wanted to use this particular scope as the test scope for sky conditions to compare contrast with my open truss scope. My worst suspicions where realised sky wise, thankfully not scope wise. NGC 253 became easier to make out with this TMB Planetary 9mm with the darkened background sky glow. Variation in brightness was noticeable with a brighter core and fading elongated disk.

I am really impressed with this EP. A worthy addition to my collection, and a as good a stable mate as the 6mm I already have.

Thanks, Sylvain. I am in no way disappointed, and all my expectations have been met with this brilliant eyepiece.

Mental.

PS- I forgot to mention the eyerelief: huge.

That is another great feature of these TMB Planetary Type II's, the fantastic eyerielf means much more comfortable viewing as you don't need to sit your cornea on the eye lens to both see into it & see the entire FOV.

Another feature of these EPs is they have a twist cap sleeve. By giving this cap a twist, you raise and lower the rubber eye cup to the most comfortable position for you.

Love it!