Lens cleaning advise?

[J_asper]

Hello guys I have 2 enlarger lenses that I can’t seem to get clean. I have used Zeiss cleaning liquid and Kodak lens cleaning liquid with Lens cleaning cloth. Unfortunately as you can see in the pictures this did not do the job. I have on order isopropanol which arrives tomorrow but have not used that before on lens elements.

The 240mm( first two photos, black barrel) I had completely disassembled and cleaned the elements one by one.

Any suggestions on what the next step should be?

Thanks!

 

[koraks]

The coating is probably damaged on those lenses. I doubt the alcohol will help, but give it a try. If it doesn't help, accept the situation. If you use these as enlarger lenses, the impact on image quality will be virtually insignificant.