Ok to spray paint a lens?

[jarrods]

I've a pair of 2308 plastic lenses; slight variations in colour on the blades and a line of glue on a cracked one. Is it ok to give them a spray of matt black paint or does that effect the relective properties at high frequences?

thanks, Jarrod

[Hofmannhp]

Originally posted by jarrods
I've a pair of 2308 plastic lenses; slight variations in colour on the blades and a line of glue on a cracked one. Is it ok to give them a spray of matt black paint or does that effect the relective properties at high frequences?

thanks, Jarrod

Hi Jarrod,

for my opinion, the painting cannot affect any sound differents in cause of the wavelength of the high frequencies. This wavelenght is minimum 1.5cm, or 1/4 length of about 4mm. The painting raughness maybe less then 0.01mm. So ....short...it doesnt matter.
BTW: Have you seen that the original lens are painted with a thin matt black paint on the plastic surface?

HP

[jarrods]

hi HP,

yes upon closer inspection one of the lenses certainly does have a very thin coat of a mattish black paint; gone in places adding to the motley effect.

they are miles apart in serials (53885, 78996) and somewhere along the 25,000 in between they must have changed their minds as to the final finish required.

anyway today I have removed the foil labels, scrubbed them in the kitchen sink with the bottle brush (n.b. no wife!) and when they dry they will be sprayed matt black.

-jarrod

[Tom Loizeaux]

You might prefer them in a satin or semi-gloss black finish ...which would be closer to the look of the original sartin plastic.

Tom