Zambuto 10" mirror vs. Meade and Orion.

Is there really a big difference between say a Zambuto 10" mirror vs. a Meade or Orion 10" mirror? Basically what I'm trying to ask is does every mirror in a 10" Meade or Orion dob have some type of imperfection with it? Are some of them Zambuto quality? How close are they to Zambuto?

I know Zambuto probably uses better coatings. But I'm not really asking about coatings, I'm really mostly just asking about the mirror shape.

Chris,

I seen and owned excellent samples of 10" mirrors from both Meade and Orion. However, several months ago, I purchased a 10" Starmaster EL used and was amazed at the contrast of the Zambuto mirror. I was one of those who thought most of what I heard about Zambuto optics was just hype from over zealous buyers. I was wrong. I immediately sold the scope and ordered a new and larger one from Starmaster. I now have the 16" Starmaster with Zambuto optics and am delighted with the contrast you get from the extremely smooth finish of these mirrors.

That said, for the money, you can get some very nice optics from Meade and Orion.

Randy

I've observed using telescopes with 8" and 12.5" Zambuto mirrors on a regular basis. I found that there was an appreciable difference between my Zambuto mirrors and what's regularly available from Orion and Meade.

I can't judge whether this difference is important to you. I'd suggest that you attend a few star parties and find out for yourself.

Hi Chris,

Just wanted to give you some info on Zambuto Optical and Zambuto mirrors in general. Your first question was:

>>Q: Is there really a big difference between say a Zambuto 10" mirror vs. a Meade or Orion 10" mirror?

There are some fundemental differences between mass produced mirrors and those done Done by Zambuto Optical.

First of all is the concept of annealing the mirrors pyrex substraight to remove all strain. All of the mirrors that come out of Zambuto's shop are tested for strain and striation before ever making it to a machine to be worked. In the past blanks not passing the anneal test would have been simply boxed back up and returned to the vendor. Currently Zambuto Optical is having their blanks custom annealed and this is no longer an issue. But why is this important and don't the Orion's and Meade's of the world do the same. Strain effects the ability of the glass to hold a stable shape while being figured and also will cause problems with the mirror's figure any time the glass is heated or cooled. And yes, others do have concerns about annealing, but a mirror that might be considered passable to them could still have failed in Zambuto's shop. In other words: If it shows any strain, it fails.

Striation: This is simply a case where when the Pyrex glass was melted it was not mixed well enough and leaves areas of different physical characteristics throughout the blank. One area may be softer than another, or expand and contract at a different rate than other parts of the mirror. Where a poorly annealed piece can be "re-annealed" the only cure for most striated glass is the local fire hydrant. Striated glass is nearly impossible to figure and even then the figure changes depending on the glasses mood on any given day. Continued in part II