perfect parabola - hard to grind?

Hi Guys,
I am new in the field and I just have started gathering materials and reading about ATM.

Although vast majority of people say that a parabolic mirror is necessary for good quality pictures in newtonian telescope (no spherical abberation), I found some suggestions about grinding a spherical mirror. They say that making proper parabolic shape is "extremely difficult to even an experienced mirror maker". Moreover they argue that they have never seen blurred picture using spherical mirror...
But then you have to follow Maksutov equation (lamda/4) and 8'' mirror (that I am planning to make) would have to have focal length = 72 inches. That would make focal ratio f/9 ! It is kind of awkward... :S (or it isn't?)

So my question is: is it really so hard to make perfect parabolic 8'' mirror for a guy with lots of patience and excellent manual skills like me? 8)

Thanks for any advice!

Marcin,
A 'perfect' parabola is impossible to grind. A really, really good one is quite doable. In an 8" mirror a parabola is the only way to go. Patience (which you say you have) is probably the most important ingredient needed.
Look for Jean Texereau's book 'How to Make a Telescope' or others that are available and don't be intimidated. Dive on in. Great joy and pride can be derived from viewing through a scope you know you made.
[COLOR="Red"]Caution!! [/COLOR] Amateur Telescope Making is addictive.

Bob

Hi, Marcin,

You've already gotten some good advice, and it doesn't sound like you need any more encouragement, but here's an article on the subject that I wrote for my club newsletter a couple years ago. There's nothing like the personal satisfaction you'll get when you look through a telescope with a mirror you made yourself.

http://www.umich.edu/~lowbrows/reflections/2003/dscobel.11.html

As others have said, go ahead and do it!

Doug