Pupil lens coating refelections after cleaning (1 Viewer)

[Dr. Amnon Duvdevany]

Wrote this to Leica forum (regarding Leica Ultravid), but maybe this is the right place.

After cleaning the pupil lens very gently (wiping dirt, using an optical chamois cloth and breath moisture), some local changes of the coating reflection colors (blue-red-green) can be noticed when you look carefully (and closely) for the reflections against artificial light source. Don't they have any optical/performances meaning at all (is it just cosmetics), or should the lens be cleaned further to eliminate them and have even color reflection?

Thanks in advance

 

[ceasar]

I believe there were several answers to your query in the Leica forum. You will probably find them helpful. I wouldn't worry about the lens reflections. There is a detailed thread here on how to clean binocular lenses.
http://www.birdforum.net/showthread.php?t=30927
Cordially,
Bob

 

[Surveyor]

Wrote this to Leica forum (regarding Leica Ultravid), but maybe this is the right place.

against artificial light source.

Thanks in advance

Hello Amnon;

Since you specified artificial light this time, but not the type, you may try looking in direct sun light or a broad band halogen light source.

If you were using flourescent or CF bulb you can get different reflections from different incident angles since reflectance can change with incident angle and the colors are far more individual and peaked.

Have a good day.
Ron

 

[Surveyor]

Hi Amnon;

I think what you are seeing is normal. I got my Ultravids and looked at the oculars under a CF light and sunlight.

Under the CF light the small reflections were magenta colored and the larger reflections were cyan-blue colored. The blue tints changed towards magenta as they were moved towards the edges.

I had about the same results under sunlight and halogen lights, though the colors were more subdued.

Hope this helps.

Ron

 

[Dr. Amnon Duvdevany]

refelection colors

Hi
Thanks to all.
Wish to mention that there is difference between the lenses (the one that was not cleaned and the one that was). It looks like the "trails" of the wiping. It is noticed more when you look closely at refelecions from a bulb etc.
Amnon

 

[Boomer]

Hi Ammon,
Might be some streaking/smearing due to residue from the wiping. Those dastardly streaks/smears are very difficult to completely remove. I hope that this is the case, rather than the optical coating being harmed. Best wishes.

Ron Davidson

 

[ColonelBlimp]

Also something very similar happened to me with some Opticron Imagic BGA SEs-details in the Opticron forum.