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[marlenedegrood]

When looking at a lens such as a Kodak Commercial Ektar 14" lens, how does one look at it to look for problems. I have this lens and I plan on selling it on Ebay, I'v had the shutter calibrated and it's ready to sell, but when I'm asked if it has hazing, cleaning marks or fungus......I don't know how to tell. The glass looks free of scratches and clear but when I look really close and at just the right angle, I see 2 areas of very small lines resembling a lightening strike....but these are extremely small and hard to see. I also see what looks like a series of scratches following the circumference of the lens (outside of center), but although this looks like scratches from a circular motion when cleaning, they are on the inside. Keep in mind these flaws are really hard to see and I probably never would have noticed expect that a prospective buyer emailed me and asked me to examine the lens with a light bulb behind it, even then I had to angle the lens around to see these flaws.

Here's my question.....what is this and how do I describe it?

Thanks so much!

_________________
Marlene
http://www.thedigitalspectrum.com

[ This Message was edited by: marlenedegrood on 2003-05-09 17:27 ]

[45PSS]

With shutter open and looking thru it at a light and it appears crystal clear then it has no haze, cloudiness, or fungus as any of these would show up readily.
The marks you describe as circular and barely visible when holding the lens at an angle to the light are cleaning marks. As you have them described I would consider them as "very slight". The lines you describe as lightning streaks may be fungus begining, most likely won't hurt lens preformance.
Check both front and rear elements with the shutter closed and describe each group seperately.
Charles

_________________
The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU.

[RichS]

Since your looking to sell and I am a perenial buyer, I'll offer up what I examine in a lens...
To me, anything that states 'mint', 'crystal clear', "no scratches, haze or cleaning marks", etc. means exactly that. The glass should be almost invisible (unless coated of course).
When I get a lens, I first give it the obvious look at. Then I open the shutter and look through. Still shouldn't be able to see _anything_. The next test is done with a light bulb shining at an extreme angle across front or rear element and then looking through the other end. This will show any cleaning marks.

The final test is done using the same light bulb, but looking at the same element it's shining on. But now I use a loupe and examine the glass surface itself. This shows any scratches or imperfections in the coating or glass.

If I see anything at all, the lens is not perfect, mint, crystal clear, etc...
A lens can still be completely useable with imperfections or slight marks in the coatings as long as they're in the rear element or a hood is used around the front element. Anything at all inbetween elements is unacceptable as it's either separation in the cement or fungus and can't be cleaned or repaired ( affordably). I'm not overly critical about _slight_ cleaning marks and have quite a few lenses with them. They work fine, but their cost was comperable to the marks.

I've found the best test of a lens is using the loupe. It finds anything with the right angle and reflection of a light source. It also magnifies the problems and I understand what I see and how it will affect my photos.

If you haven't done it yet, remove the elements from the shutter and clean the inner surfaces. I've had quite a few lenses that looked terrible until the insides were given a standard cleaning. It's amazing what will build up in there over 30 or 40 years. And if they were once cleaned, a circular 'haze' is very possible because no cleaning is perfect. There's always some residue left over that particles will cling to. I recently bought a lens that I almost returned because it was so hazy on the inside. And I still swear that the haze was caused by decomposing paint on the inside of the shutter. The tissues actualy turned black when I cleaned the inside surfaces. It's perfectly clear now...

To prevent any hard feelings with a buyer, I would recommend mentioning anything you see in the lens as honestly as possible. You don't necessarily have to know what it is as long as you mention it. There are a lot of people out there who know that a slight cleaning mark will have no affect on performance as long as they know how to use the lens, and they will bid accordingly...

[marlenedegrood]

Thank you both for your great explanations! You've been a lot of help!

_________________
Marlene
www.thedigitalspectrum.com