MichaelG - The repair work was cementing a prism which had come loose. The scope was sold as 'not working', so I bought it mainly for spares. I was disappointed to find the loose prism, but luckily it appeared not to be damaged and the cement was still there so I decided that with a bit of luck I could get it back in just the same position. I think it's probably 'near enough'. There's no obvious distortion or doubling of the image, etc. The illuminator is original, using a 100W halogen bulb. The photos I posted aren't good but they were taken quickly, just to show the colours.
But as MicroBob says, the difference looks about the same in both scopes so I wonder if it is just an extra layer of optical cement or something in one eyepiece which colours sllightly with age? Is that possible?
Thanks for the clarification, Tim ... it appears that you have only cemented an existing prism back in place ... I initially thought that you had re-cemented the optical faces of a built-up prism.
Also thanks for confirming Tungsten lighting.
As for the 'extra layer' of coloured cement ... Yes, I think that likely but; as I don't know the optical path in this binocular, it's currently only a guess.