What's this 'scratch' on a Canon 50mm 1.5 LTM?

[taemo]

I'm interested on aquiring a 50mm 1.5 Sonnar and saw this Canon 50mm 1.5 LTM for sale.

The seller description is "a tiny scratch on the front element" however it does not look like a scratch to me.
Any idea what could it be and is it common with old Canon lenses?

 

[Mackinaw]

It's not a scratch. Could be a flaw in the coating or the beginnings of fungus.

These type of flaws are not unusual in any lens that is 50+ years old. Time takes its toll.

Jim B.

 

[Roger Hicks]

Looks like separation or fungus (more like the latter, though it's hard to tell from the photo). I wouldn't touch it.

Cheers,

R.

 

[FrankS]

Can separation happen in the middle of 2 lens elements?
Or must it start from an edge?
I really don't know, just asking.

 

[Roger Hicks]

Can separation happen in the middle of 2 lens elements?
Or must it start from an edge?
I really don't know, just asking.

Dear Frank,

Same here. But I think that it can, after an impact.

Cheers,

R.

 

[johannielscom]

Coating discoloration.

Likely that lens has been stored with a filter attached for a long time.

The Canon lenses always had very little clearance between center of front lens element and filter. If you leave a filter on for a very long time and fungus starts to build up, the most 'cozy' spot for it is the middle of the front element.

I had a 1.2/50mm with a coating spot too and once I mounted a filter, I could see it was dead center.


It might impact contrast a bit, but not too much. It ain't pretty either though...

 

[taemo]

thanks all for sharing your expertise regarding this lens.

so this means that it might just be a fault on the lens element (separation/discoloration) BUT it might lead to fungus down the road?

 

[farlymac]

It's on an external surface if it's what Johan suggests. The only things that leads to fungus is moisture, and darkness. Use it regularly, and you shouldn't have a problem with it.

PF

 

[xayraa33]

It can be separation if the lens has had a good rap on its centre front.

That multi colour oil-on- water looking blotch looks to be separation from a bad hit.

 

[taemo]

thanks everyone, i might give it a try, take some test shots and see if I can get a bargain price on it.

 

[goamules]

Checking ebay, I see these sell for half or less what they sold for 6 or 8 years ago. It probably already is a bargain price.

 

[BLKRCAT]

I wouldnt do it. Buying "fixer upper" gear never works for me.

You can ask my rigid summicron I bought in a similar state and had the front element overhauled by focal point. After that talk to my wallet.

My wallet and camera gear don't like each other so much...

 

[xayraa33]

It probably is a good photo making lens for a low price.

The Canon/Serenar 50mm f1.5 is one of my favourite lenses, although I found out that the Nikkor 50mm f1.4 is a little sharper at close to full bore, regardless of the occasional veiling flare wide open.

 

[iphoenix]

My Canon 50/1.5 s/no. 24714's front element centre is at least 2mm from the Canon UV filter attached to it. On that basis I don't think a filter (if Canon) is the problem.

The picture of the problem seems to me to be "blooming" between the lens elements, which may get worse but if you use a hood, shouldn't effect the pictures.

David