Disassembly of chrome Canon 50mm 1.8

[RainDance]

So I have a Canon 50mm 1.8 Serenar sitting in my cupboard. It has haze, and I want to clean it. I got as far as removing the focusing helicoid but that is it, there is a retaining ring I can remove but it seems to do nothing. Tried unscrewing the assembly for the glass itself but it wont budge. Any guides or advice?

 

[xayraa33]

It cannot be that much different than the later made black LTM Canon 50mm f1.8 to take apart.

http://jelabs.blogspot.com/2011/04/canon-serenar-f18-50mm-ltm-lens.html

https://www.youtube.com/watch?v=HX93S2iuG5E&t=239s

 

[RainDance]

Saw that online guide, the problem is in the picture the rear lens seems to have two sets of notches for a spanner. Mine has one (inner only) and when I remove it nothing really comes out. Thank you for the video I will have a look at that.

 

[Peter Jennings]

On some lenses, the whole rear optical assembly unscrews as a single unit. This will expose the aperture blades. Most likely, the haze you are seeing is on the rear lens surface facing the aperture blades. In most cases, this haze is actually a corroded etching that is near impossible to remove. In some cases it is fixable. Hopefully, yours is, as well. Best of luck!

 

[peterm1]

So I have a Canon 50mm 1.8 Serenar sitting in my cupboard. It has haze, and I want to clean it. I got as far as removing the focusing helicoid but that is it, there is a retaining ring I can remove but it seems to do nothing. Tried unscrewing the assembly for the glass itself but it wont budge. Any guides or advice?

For some reason (I expect, related to the lubricant used by Canon possibly combined with Japan's humid summers) Canon lenses of that era seem especially prone to haze / fogging. As someone else points out some haze is readily removable and some is not as it can etch the element on which it exists.

If it is proving problematic Google it. I had cause to do so recently as I had a lens with this issue and found a number of threads on the topic. If conventional treatments do not work, most people use something containing a superfine abrasive like flitz metal polish or cerium oxide lens / gem polishing powder. Either will also remove the coating of course but that my be preferable if the hazing is bad.

Good luck with disassembly and with cleaning. Its a "journey"!

EDIT: I thought I had seen something on disassembly and cleaning of this lens. I did a quick search and came up with this link. Its for the Serenar (i.e. early) version of the 50mm f1.8 chrome but may help.

http://jelabs.blogspot.com/2011/04/canon-serenar-f18-50mm-ltm-lens.html

Also this:

https://oldcam.wordpress.com/2014/01/19/canon-rangefinder-lens-servicing/

 

[dxq.canada]

The rear element unscrew. From what I remember (and shown in my blog post) the top group has two notches for a spanner ... for the next part also has two holes. I think the first time I did this, both parts unscrewed as one.