Quote:
|
Originally Posted by mpierich
Interesting. As far as aluminum, there's an article somewhere on here re the aerospace/atronomy people not being able to get aluminum to optical quality and experimenting with india ink as a finishing media. Sounds messy, huh?
|
Yea, I saw that, Aluminum is more sensitive to temperature changes, condensation, and a number of other things that can degrade a reflection. It is basically porosity that makes the metal light weight and gasses are trapped in the pores and will expand and bleed out.
These pores also can be the limiting factor in achieving the quality of finish needed for optics. You some times here me say the limits of the metal, mostly when referring to polished castings. Heavy porosity = dull. As long as I am on the subject of porosity and gasses I will say that I never recommend chroming aluminum for just that reason as well as a few other reasons. However if money is of no concern and ease of maintenance is top concern, then chrome away.