Old mirrors verse todays bargain mirrors ?

[Bobbyoutback]

Just curious to hear opinions regarding the optical performance of the cheap 10" F/5 mirrors available in todays Dobs .
I have an old 10" F/6 mirror made for Astro Optical , think these were hand figured , wonder if it performs better ? :question:

[MrB]

Pretty good chance Mark (Satchmo) did your mirror. Might be worth sending him a PM?

[Bobbyoutback]

Thanks for the info MrB .

Wish someone would tell me the optical performance difference between the old & new :confused2:

Regards
Bobby.

[MrB]

At a guess, I would say the hand figured Astro Optical would be superior to an off-the-shelf mass-produced GSO primary.
I have no experience with either tho, hence my suggestion to contact Mark.
I reckon he would know what performance you could expect from a mirror he has probably personally figured.

[Bobbyoutback]

Thats the big Question , I would like to think the same :) , this subject has received a lot of views but only you & I are assuming so !

Cheers
Bobby .

[Bobbyoutback]

After the perthetic responce to this question let me direct this quote to those who could have responded :(

The individual has always had to struggle to keep from being overwhelmed by the tribe , if you try it , you will be lonely often & sometimes frightened .
But no price is too high to pay for the privilege of Owning yourself .

Friedrich Nietzsche .

[Poita]

I have no idea, the easiest option would be to get to a starparty I guess and see some side by side for visual performance.

Hand figuiring is down to how good the person doing it is, I guess the only sure answer would to get an old and a new and get them tested.

I'm guessing the lack of response is because the people who have viewed the thread simply don't know, or just as likely, the question really can't be answered by anyone who doesn't have the particular mirrors to be compared.

An old hand-figured mirror could be a dud or an absolute corker, no way to know if one hasn't seen it.

[Satchmo]

Thats correct- there were thousands of 10" F6 mirrors made by AASC/Astro Optical over a 30 year period by a number of different people some less skilled rthan others. The only way is to know is to get it tested or get it into a tube and star test. If there is a 3 digit number on the back in indelible texta between 001 and 340 it may be one of mine- I still have my notes from my period there.

BTW Bobby , no one on IIS `owes' anyone a satisfactory response on any topic..be grateful that anyone reads your post at all and then you may be pleasantly surprised :)

[astroron]

Quote)
BTW Bobby , no one on IIS `owes' anyone a satisfactory response on any topic..be grateful that anyone reads your post at all and then you may be pleasantly surprised :).

Well Said, Mark,my sentiments exactly.:thumbsup:
Cheers

[astroron]

Go on Google and put the question:question:
You will probably find the information there ,or even try Cloudy Nights web site.
Cheers

[ZeroID]

In reality there is no answer to the question.
Some older mirrors were made by experts, others were not.
Newer mass produced mirrors are on the whole more consistently of better quality but not necessarily better than a well made earlier mirror.

There are no rules ...

[Bobbyoutback]

Thanks for your comments & others , please be assured that there is no malice in my very dry sence of humour :D

Cheers
Bobby.