Photochromics in different materials

[ak47]

It seems that transitions trivex does not get as dark as transitions in poly. Has anyone noticed a difference between Trilogy Trivex Transitions and Phoenix Trivex Transitions - which get darker?

What would you recommend for darkest photochromic FT 28 in hot, desert climate ?

[Sledzinator]

If you can do CR39 you can do the transitions extra active.

[braheem24]

if you need a higher index call state optical 1-800-622-5367 their 1.56 FT-28 is as dark as Transitions in poly or 1.50 and less expensive.

[standarduck]

if you need a higher index call state optical 1-800-622-5367 their 1.56 FT-28 is as dark as Transitions in poly or 1.50 and less expensive.

Isn't 1.56 really brittle though? Would seem odd to swap that interchangably with poly.