The Kodak 203mm f7.7 Ektar lens has a lot of people singing its praises. The weight is light enough to carry into the field, and the lens is very sharp, and very inexpensive for a LF lens.

My question is how does one differentiate between the uncoated and coated versions of this lens? Does the shutter or serial number give any clues? Is there a way to tell by looking at the reflections inside the lens? Any info appreciated.

Regards,

-- Martin F. Melhus (melhus@fdrc.iit.edu), January 08, 1999

Answers

I thought all Ektars were single coated. I may be wrong. Look at a reflection in the lens surface, and see if it has a slight blue or purple color cast to it. If so, it is coated.

-- Ron Shaw (shaw9@llnl.gov), January 08, 1999.

Multi-coated lenses usually will reflect two different colors when placed at an angle to a light source and moved around, a purplish color and a greenish color. In the lenses I own that I know are multi-coated, these two colors can be clearly seen as the lens is moved around at an angle to a light source. I thought, but am not certain, that if you see only a purplish color the lens is single coated and if you see no color at all the lens is uncoated. However, I don't own any lenses that are uncoated or single coated so I cannot be sure of this. Perhaps someone else can confirm this or correct me.

-- Brian Ellis (beellis@gte.net), January 08, 1999.

FWIW

I own un-coated lenses and single coated lenses. I used to own a multi-coated 65mm but I didn't use it very much so I traded it & can't compare between multi- single- and non. However, the difference between an un-coated lens and a lens with any coatings should be as clear as, well, as clear as glass. My single-coated lenses have multiple reflections but they are only in two colors, a pinkish lavender and a light blue.

-- Sean yates (yatescats@yahoo.com), January 08, 1999.