Yashicamat 124G lens marks -- what is this?

[lbloom]

Hello all,

I bought a Yashicamat 124G, and was examining it. When looking through the taking lens on bulb, a prominent streak is seen.

1 o'clock:


From the back; 11 o'clock:


A closer look. 1 o'clock on both.




Is this fungus? When viewed from the back, it is behind and close to the rear element.

I gather that it is relatively simple to open this lens up, but I don't own a wrench spanner, and do not want to tamper with it unless I decide to keep it.

Any idea or comments would be helpful. Thanks very much.

 

[Chrismat]

It does look like it could be fungus. I've never attempted to try to remove fungus before but you could try to call Mark Hama, he does a great job repairing Yashicas, especially TLRs since he used to build them in Japan. It's easier to speak to him over the phone than e-mailing him. You can get his phone number at www.markhama.com

 

[johnielvis]

likely fungus---if I'm right that is....

the lens just needs a cleaning to determine...however

since the lens is a tessar, the front elements are not cemented, but the rear are---and the fungus attacks the cement as far as I know exclusively....since it's on the back element--the rear 2 are cemented the front 2 are not, then it sure seems like that's the culprit....

hey--I need to clean mine...it's got dust in there--just bought it....if you figure out how to take it apart easily...like maybe from the back get the rear out with a spanner, let me know ok

 

[tkamiya]

I don't know about cement but fungus also attacks coatings, such as multi-coating. I hear they are yummy.

To me, it looks like combination of dust, oil residues, fungus, and multitude of contamination. It definitely needs cleaning. To me, the fungus part does not look bad. On photo 3, there is a big thick streak at 1 o'clock. That one is definitely fungus.

I've taken lenses apart and cleaned them myself. Depending on how much you paid for the camera, you may or may not try this yourself.

If you have a chance to return it, I would. 124Gs are available fairly reasonably these days. Professional cleaning will likely run you decent amount of money.

 

[Dan Daniel]

A guide to removing and cleaning the lenses on a 124... for people who believe in real tools, take a deep breathe before clicking on this link and seeing how the guy made a spanner wrench (nails, board, dremel.... it ain't pretty!)-
Dead Link Removed

 

[lbloom]

Thanks for the comments and wealth of information, folks. Much appreciated.

 

[Kevin Kehler]

I had very similar marks on my 124G - the shutter is noted for throwing off oil over time. So don't necessarily jump to fungus although it does look like that to me; however a good repair shop should be able to clean it properly. It was about $60 for my repair guy to work it over but I haven't had an issue since.

 

[johnielvis]

heY...thanks for that link!!!!! I even have a proper spanner--this should be an easy job to clean mine!!!!!