Lens Haze.

What is the haze sometimes found on the rear elements of (usually older) lenses and what causes it?

More importantly, can it be removed and if so, by what means?....a forum search suggests that this question is rarely asked and not really answered.

I have tried elbow grease, isopropyl alcohol, spit and vigorous rubbing - with only limited success..

Oddly, the presence of the haze does not seem to have that detrimental an effect on image quality?

Are you referring to uncoated lenses? If so, you have rediscovered the precursor to coating.

It was noticed that lenses gained a hazy surface, no doubt due to atmospheric reactions with the glass, pollutants, etc. It was also noticed that lenses that gained this hazy coating had reduced flare.

It was then a small but difficult step to inventing coating procedures.

I am quite reassured by that John - that presumably explains why this particular old lens, a 200mm prime, performs surprisingly well. The front lens group seems quite devoid of any obvious coating colouration, the rear group has quite a strong blue caste.


Roger.

That then would be better termed a 'bloom' rather than haze. Serious hazing, which can originate from grease traces or poor storage conditions, can reduce contrast quite considerably.

Originally lens coating was indeed called blooming.