Refiguring a mirror

[OneEyedSam]

I've got a 12" f5 mirror (lightbridge), Ive done a ronchi test of it and it look ok, ie there are no serious issues with it, but I cant help wonder how much of a difference it would make if I either replaced it with a mirror from someone like Nichol Optics , or wether I had the mirror re-figured .

A new 1/8 wave mirror from nichol would be about £900 all told, I guess refiguring will be dependant on the time it needs on the polishing machine, but I'm guessing 3-400 quid.

Thoughts any one ?

[Laurie61]

If you want to upgrade the optics it might be easer to sell the Meade and buy a better one second hand. This one has been on abs for a while and would be a nice improvement. http://www.astrobuysell.com/uk/propview.php?view=76815 

This is 1/10 wave 

[Moonshane]

I agree with the above principle but that one albeit nice indeed, is an f6 mirror so you'd need to lengthen your truss poles or sell the LB and make/buy a new OOUK base?

[NGC 1502]

I've got a 12" f5 mirror (lightbridge), Ive done a ronchi test of it and it look ok, ie there are no serious issues with it, but I cant help wonder how much of a difference it would make if I either replaced it with a mirror from someone like Nichol Optics , or wether I had the mirror re-figured .

A new 1/8 wave mirror from nichol would be about £900 all told, I guess refiguring will be dependant on the time it needs on the polishing machine, but I'm guessing 3-400 quid.

Thoughts any one ?

It's a tough one as to whether a refigure would improve the views.  You've done a ronchi test, and it looked ok, so if the views are good when the scope is cooled & collimated, I'd be happy myself.  

Jupiter is a great test of how good a mirror actually is, full of low contrast detail if the seeing is good.

Speaking personally, I'm far more interested in the views, rather than theoretical mirror specification, although it's nice to know you have a top mirror of course.

A friend of mine had a 17.5" mirror refigured here   http://www.oldham-optical.co.uk/index.htm   but as the boss has recently retired, don't know if they still refigure.

If you are thinking of how good the primary mirror is, how good is the secondary ?

Maybe get a couple of quotes, add the cost of the necessary recoat plus petrol or shipping ( and hassle ) - see how you feel about it.

Hope you reach a happy conclusion, Ed.