Post CLA M-SYSTEM 75-150mm F4

M-SYSTEM 75-150mm F4

The lens came with very clean front and rear elements but the middle group has a smear of haze

Did some research before opening it up for a CLA attempt. It seems that the problem is very common in this lens.

Sadly I forgot to take a photo with the lens before cleaning.

It can be seen that the haze was quite thick and I had to open it up to clean it.

After opening it up, I realised that I could not access the middle group.

There was a tutorial of cleaning this lens but the guy was lucky, the haze was on the top side of the element so it was an easy fix for him. Sadly, for mine, it's on both sides. Probably because this lens is older than his. I have no clue.

I thought I could not fix it when I first tried it, until I thought of a way to slide a wiper into the slit between the element and the barrel.

After cleaning it for the first time, there was still some marks on the element, which you can see on the top right. Then I opened it up a few more times.

Frankly speaking, there's still some haze around the very edge of the lens but that's the best I can get at the moment.

Some post CLA test shots.

At 75mm F4

At 150mm F4

This lens is not particularly sharp.

However, to make it overall functional is good enough already. Also, the purpose of having it is to complete the collection.

The infinity focus adjustment is a pain in the S.

Cheers,

Wilfred