11 replies to this topic

[asaint]

15" f/4.5 Teeter Dob

[ForgottenMObject]

Those Teeter's Dobs really are impressive!

[ezrider23]

Nice review. Like many people in the astro community, Rob Teeter is a top notch guy. My dealings with him have been very positive. I get frequent updates on the status of my scope being built. I get prompt replies to any questions I have concerning the scope, and we also changed the layout on the mirror box in regards to fan placement to get better air flow aross the mirror. I wouldnt hesitate to recommend Rob if somebody is in the market for a truss dob.

[sixela]

Just curious - how much higher than the mirror did your fans end up?

[ezrider23]

They are being placed slightly closer together as a small slice of the mirror was not getting direct airflow. So the name plate and some handles are being placed different.

[MikeRatcliff]

What was the price?

[pico375]

Nice article, Ernie. I had the opportunity to meet Rob, his partner, visit the shop (the old shop) and gander at a few scopes in production. Teeter's is indeed a top notch operation. Enjoy your scope for many, many years to come.

Clear Skies,

Larry

[RobTeeter]

Ernie's a great customer and we were really happy to be able to fill this order for him. Unfortunately Ernie isn't too wordy, so we've gotta read between the lines in his review to get even more out of it.

The mirror in this particular scope (R.F. Royce) is just phenomenal. It's just about as big as Royce likes to go and I have a hard time believing this mirror came in at his bottom line of 0.95 Strehl, it's certainly much much better than that. I would applaud Royce right here and now, but my hands are quite tired from doing that every time I look through a scope with his mirror in it.

Take care,

Rob Teeter
Owner, Teeter's Telescopes

[aporigine]

Perhaps Ernie's wife might add a few words about what the Teeter taught'er. (ducking)

[sixela]

They are being placed slightly closer together as a small slice of the mirror was not getting direct airflow. So the name plate and some handles are being placed different.

Yes - but I was wondering how *high* they were in the box with respect to the mirror.

I have a similar setup, with the fans' bottom 2cm higher than the mirror's face, and if I set them up pulling air, I have to put a baffle at the top of the circumference to avoid them pulling air mainly from the top of the mirror box (instead of from the face of the mirror). I'm wondering if they may not just have been placed slightly too high (not that I'm going to change things now that it works - just wondering. The drawback to the baffles is that I can no longer transport the secondary cage in the mirror box).

[Jim Cook]

"This is a wonderful planetary scope even though it's only an f/4.5 ratio due to the top quality mirrors used."

I don't understand why you used the phrase "even though". Would a larger f/ ratio make a difference?

I ask this because the November issue of Astronomy magazine makes a big deal of the views through a public f/7 31" Newtonian, but much less of a deal of a f/4.5 30" Newtonian.

[jpcannavo]

Jim
The difference is that 1)its harder- to figure a faster mirror to high precision (High Strehl)
2)Collimation becomes so critical in a fast scope that often they do not perform at their full potential. 3) Keeping the secondary small in a fst scope is a bit more tricky.
However these are merly challenges and not insurmountable obsticles a fast, well colimated Royce, Zambuto etc. will deliver fantastic planetary images under goo conditions.