Noobie Question No. 6: Haze. What causes it, can it always be removed?

[David.Boettcher]

I have just acquired a 3.5cm f3.5 Summaron. Cosmetically it looks great, no dings or brassing, almost like new. But when I look into it with a jewellers loupe I can see a film of haze on one of the internal surfaces. It is under warranty and will be taking a quick trip to Malcolm Taylor on Monday to get his opinion. But this has given me some questions about haze.

1. What is haze - I mean what causes it?

2. Can it always be removed?

3. Does it damage the surface of the glass?

4. Once removed, will it return?

Thanks for any information!

Regards - David

 

[ferider]

1. What is haze - I mean what causes it?

2. Can it always be removed?

3. Does it damage the surface of the glass?

4. Once removed, will it return?

1. Can be a variety of reasons. Most often it happens on surfaces before and after the aperture, stemming from focus or aperture lubricants, intruding via the aperture mechanics.

2. More often than not, at least in large parts. Sometimes it can etch the affected surfaces, cause fungus, or due to soft coating, cleaning haze can damage the coating.

3. See 2.

4. Yes. Some lenses (like many classic Canon LTM lenses), unless lubricant is replaced, it can return in less than 6 months. For your typical Leica lens it will take many years, if cleaned correctly.

Roland.

 

[David.Boettcher]

I think I read somewhere that Leitz used whale oil on the aperture blades and that stuff evaporating from this and landing on the elements could cause haze.

Whether this is true or not, presumably the lubricants available when these lenses were made were all natural and probably not as good as modern lubricants. Presumably if all the old lubricants in the lens were removed and replaced with modern versions this would help to avoid the problem recurring?

Regards - David

 

[David Hughes]

It really depends on what you call modern lubricants. Dow Corning, Rocol and a lot of others had some amazing stuff available in the 60's. And I can remember my father going on about stuff they used on some Govt. contracts that came from Rolls Royce. And, of course, the super-glues were available and so on.

And others still use Castor oil and swore by it... And gear boxes were saved with crushed bananas and so on.

I expect you'll get a pleasant surprise when the lens is returned.

Regards, David

 

[Frank Petronio]

For some lenses, it may actually be better to shoot them hazy. If you want to capture that Leica glow, to some extent it is coming from the 60-year old haze.

 

[David.Boettcher]

Get it cleaned, or leave it hazy?

Get it cleaned, or leave it hazy?

For some lenses, it may actually be better to shoot them hazy. If you want to capture that Leica glow, to some extent it is coming from the 60-year old haze.

Hmmmmmmmm; now there's a thought . . .

My initial thought was to get Malcolm to clean it up as close to new as possible. But thanks Frank Version Two: you made me stop and think, which is always great. I am still inclined to get it cleaned, but at least I now have 24hours to think about it. It's always better to think about these things beforehand, rather than afterwards when it's too late to do anything about it.

Will I be restoring a fine optical instrument to its true performance, or will I be destroying the patina of age that only time can supply, and which once gone cannot be replaced?

What do others think: get it cleaned, or leave it hazy?

Regards - David

 

[Gabriel M.A.]

http://lmgtfy.com/?q=lens+haze+causes

 

[David.Boettcher]

http://lmgtfy.com/?q=lens+haze+causes

Hi, yeah, well, thanks for that: but I did of course try googling it for myself before posting here, and I found a lot of spurious and irrelevant information about canon and nikon and coated lenses, and the usual wiffle waffle and supposition that one finds on the internet.

I wanted to find out specifically about Leica problems and solutions, which is why I posted my question here.

Regards - David

 

[David Hughes]

Get it cleaned is my 2d worth.

You can always buy a soft focus filter or scan and ruin in an editor. Or buy a Summar, most of them are well past their use by date and give that wonderful soft glow that we call ruined by DIY efforts. Or better still a Thambar from the 30's.

Regards, David

 

[Sonnar Brian]

Clean the haze out, use the lens as it was intended.