Fungus/haze on rear element unknown 400mm lens

Mr_fungus · Joined: 11 Dec 2015 Posts: 3

Hello all, I am not new to this forum, just never registered Smile

I happened to buy old 400mm lens and it seems it has quite a lot of fungus or haze on it, still waiting for my spanner wrench to arrive, so decided to make post, maybe someone knows what I am dealing with ?

First 2 images of fungus itself, back light.

Front light.

Lens itself : Tele-universar 400mm f6.3, front filer seems to be 72mm, lens itself has t2 mount (I think)

Front of lens, small dent on filter

Rear element

So is it fungus ? I tried cleaning it with dry wipes from outside (as far as it was possible to reach), almost no changes, seems all nastiness is inside, surprisingly all other elements are perfect clean, there are little tiny bit of oil on blades though.

Hope element will go straight off with spanner wrench and will be possible to clean.

Other thing, anyone know anything about this lens I do not have adapter yet so cant try it?

calvin83 · Joined: 12 Apr 2009 Posts: 7495 Location: Hong Kong

tomasg · Expire: 2014-04-28

Wow, from the pics i guess it s not only fungus Smile

i have no idea what it is, but in the picture where we can see the back element there are clearly visible notches, it would be easy to take out the element with a panner and try to clean it.

Himself · Expire: 2013-05-30

Don't bother cleaning it.
Better buy another lens. That kind is not expensive.

Mr_fungus · Joined: 11 Dec 2015 Posts: 3

little bit too late, money already spent, possibly quite a bit more than it was worth Very Happy

Will see if I can fix it, or make better.

cooltouch · Joined: 15 Jan 2009 Posts: 9109 Location: Houston, Texas

I used to see ads for those 400s in the back of camera magazines. Typically they sold for like $79 brand new. You can pick up examples on eBay nowadays for cheap, like $15 or $20. Easier to just buy another one. Those lenses are actually quite sharp. I own one and I've tested it out. Biggest drawback to them is a long minimum focusing distance. But it can be shortened with extension tubes.

Mr_fungus · Joined: 11 Dec 2015 Posts: 3

funny thing is I spent like 2 months trying to find cheap 400mm lens on ebay (for less that 30$, shipping included) and this was only one I was able to get. To my country shipping itself for all the cheap ones are insane (shipping cost more than overall sum I want to play, sometimes 2+ times more, but same item in US are delivered almost free) or seller dont ship at all. And all auctions get overbid in last second (and price is over what I intend to pay also).

marcusBMG · Joined: 07 Dec 2012 Posts: 1298 Location: Conwy N Wales

These old 400's (and the similar 500mm f8's) suffer from deterioration of the rear element. Shows as a white haze, often patchy. If only slight the effect of IQ is minimal. However it is not cleanable or fixable. I did try polishing one using a neighbours rotary wheel and some jewellers rouge but IQ was down.

This is an example of the haze - sankor 400mm

visualopsins · Expire: 2021-06-22

The next-to-rear element gets haze in the 400s I've seen -- Spiratone, Lentar, noname -- sometimes in a net-like pattern. I used cigarette ash to get the element squeaky clean. I could see no effect on images except perhaps a bit of contrast loss...

Gardener · Joined: 22 Sep 2013 Posts: 950 Location: USA