Need some help identifying dust vs. fungus, haze, separation

I'm just getting into vintage lenses recently, so I'm still not confident on being able to identify issues. First off, I got a couple of manual focus Pentax lenses a few months back. At the time, I checked them and thought they looked fine, just a little dusty, which isn't surprising for their age.

However, I've recently seen some posts online of lenses that I thought was also just full of dust, but people were saying it's fungus, haze, and/or separation. So, I redid the flashlight test on them, and I'm not so sure.

50/1.7 - I think this is just really dusty, but could it be separation? Hopefully not fungus?

50/1.4 - This one looks really similar to the 1.7, just whatever it is, there's way less of it.

And finally, I just got a Meyer Optik Gorlitz Primoplan 58/1.9 yesterday. The first two pictures are haze right? It seems to be one or near the rear element. The last picture has me the most worried. That spot in the middle, is that fungus?

Hi,

From the first two links you've posted, it looks to me like you just have a lot of small dust particles in your lenses. Fungus/mold often appears as spider web-like filaments, small whitish spots, or in severe cases, can have a frosted appearance. The lens may have a musty smell as well.

The third link you posted (Primoplan) appears to be the same as the first link, but haze is pretty evident as to what it is. The glass may be clean otherwise. Very slight haze does not necessarily affect the usability or your lens.

Separation of cemented elements usually has a rainbow-like appearance, often along the edges of the glass.

If you do a Google image search for these different conditions, there are some good examples that should help you identify them.

Looks like dust to me. A lot of dust mind you, especially in your 1.7. My advice would be don't fret. If you use the lens and are happy with the results, that's all that matters.

Very often you'll hear people say that dust and scratches don't affect the image quality. Well, that's obviously complete bunk, but what they mean is it doesn't affect the image quality so much that you'll notice on the average print, held at an average distance, for the average guy, or gal. I have a Yashica ML lens, 50mm at f/1.7, and I used it for two or three films thinking that 'man, this is one sharp lens' what a bargain (£17). Then I noticed a blob of fungus under close scrutiny. Sure, it degrades the image, but 'not so's you'd notice' (with thanks to Tom Waits).

Also, you could consider taking it apart and cleaning the elements, but if you can get it back together again with less dust on it, then you are a better man than me!

Thanks so much for the reply! It was very informative.

From the first two links you've posted, it looks to me like you just have a lot of small dust particles in your lenses. Fungus/mold often appears as spider web-like filaments, small whitish spots, or in severe cases, can have a frosted appearance. The lens may have a musty smell as well.

When you say “whitish spots”, how do those differ from just dust?

For the second, the “dust” seems more concentrated on one side of the lens, which is what worries me that it may actually be fungus.

There seems to be an increasing fad for photographing lenses using a powerful torch, which often makes them look pretty dire. I'd guess that even new lenses would have defects exposed when so treated. And some of the lenses mentioned are anything up to 50 years old. I think the best way to evaluate lenses is to take pictures WITH them, not OF them. Dust and haze will manifest themselves in loss of contrast, rather than loss of sharpness.

I've had some success removing less entrenched fungus behind front elements by removing the element and washing it with a soft sponge in soapy water.

Balsam separation can appear as rainbow patterns, but it can also cause what looks like haze, for example affecting many early Nikon 35/70 F/2.8 AF lenses. I've also had a little Pentax 40mm F/2.8 "Pancake" which had some marking around the edge of an internal group. It took me ages to realise that it was in the balsam between the two elements, and not susceptible to cleaning.

Here's another terrible looking lens which takes good pictures, this time the problem is cleaning marks.

And the results:

Yes, inspecting old lenses with a LED flashlight can bring on bouts of depression... In my experience haze is the biggest problem, as it kills contrast and encourages flare, really softening up the image. A few spots of fungus have no real effect upon the image; there seems to be two main types, little spots with furry edges, and spidery strands radiating out from a nucleus. The spidery ones really can cause damage to the len's coatings and surface. Separation usually seems to begin at the edge of the elements and progress out, with a tell-tale rainbow iridescence.

As John pointed out, every lens contains dust, which can look alarming under the flashlight test, but in reality it has little or no effect on the lenses performance. I'm training myself to just chill out and enjoy the old lenses, until I become truly suspicious that performance is suffering and treatment is required.

I'm just getting into vintage lenses recently, so I'm still not confident on being able to identify issues. First off, I got a couple of manual focus Pentax lenses a few months back. At the time, I checked them and thought they looked fine, just a little dusty, which isn't surprising for their age.

 

However, I've recently seen some posts online of lenses that I thought was also just full of dust, but people were saying it's fungus, haze, and/or separation. So, I redid the flashlight test on them, and I'm not so sure.

 

50/1.7 - I think this is just really dusty, but could it be separation? Hopefully not fungus?

 

50/1.4 - This one looks really similar to the 1.7, just whatever it is, there's way less of it.

 

And finally, I just got a Meyer Optik Gorlitz Primoplan 58/1.9 yesterday. The first two pictures are haze right? It seems to be one or near the rear element. The last picture has me the most worried. That spot in the middle, is that fungus?

Here's a Flickr album of a Sigma 135mm f/3.5 that someone sold me once. It had spots very like the ones on your acquisitions. I didn't keep the lens long enough to make a final determination, but I thought at the time that the spots were some kind of chemical deposition, as if lubricant or something had sublimated and then condensed on the interior elements as whitish spots.

And here's an album of a Nikkor 70-210mm f/4 that had the worst case of fungus I've ever seen. The third to last photo is a sample taken with the lens. Compare it with the last photo, taken with a much cleaner lens. You can clearly see the additional flare and loss of contrast caused by the extensive networks of fungus in the third photo.

Just to add to the above. I'm seeing nothing but dust on the posted images.

Fungus almost always looks 'spidery' with filaments growing outwards from a woolly-looking centre. If caught in the early stages, it can sometimes be burned away by exposing the lens to bright sunlight for an hour or so - off the camera of course, and not near anything combustible.

As said above; cement separation is seen as a crescent, doughnut or circular-shaped silver or rainbow coloured patch. Usually starting around the edge of the lens. It's not very common on modern lenses, but Rodenstock lenses of the 1970s and 80s seem particularly prone to it. It's not easily cured and will almost certainly get worse over time. It may or may not show up in the images, but personally I would reject any lens that shows it unless silly cheap.

There's also loss of edge blackening. This appears as little silver spots or patches in a circular pattern around the rim of the lens. Not serious, since it can be totally cured by disassembling the lens and applying a permanent black felt pen over the areas where the black paint has come loose. Schneider lenses often show the fault, and it's commonly called 'Schneideritis'.

Dust likewise can be completely removed by disassembly and application of a blower brush. You have to decide if the dust is bad enough to risk disassembling the lens though. A few large spots will do almost no harm to the image, but a fine coating of dust all over the inner surfaces may well reduce contrast enough to make cleaning worthwhile or necessary.

Cleaning damage is more often a cause of low contrast. This makes the outer surfaces of the lens look like a miniature skating rink under penlight examination. In severe cases the coating of the lens is rubbed away in patches. There's nothing that can be done about it except curse the lens's previous owner(s) and wish someone had stayed their hand with that dirty handkerchief!