Adjusting Infinity Focus

I found that one of my wide angled lenses was not reaching infinity so I decided to have a go at fixing it myself. It wasn't an expensive purchase but the lens was in fantastic condition and is quite rare. Many lenses have a similar setup for infinity focus adjustment.

The following details how I set about rectifying the problem. The folloing is for illustration purposes only. I take no responsibility for any damage caused to your equipment. All repairs should be left to an experienced technician.

1. Remove the nameplate by unscrewing it. Often you can unscrew them by using both thumbs pressing in on the nameplate. If they are stiff, there is a rubber tool which can be used.




2. Remove the screws in the coverplate shown here.



3. Set the lens to infinity focus.

4. Slacken, but do not remove the retaining screws shown here. The focus barrel will now move independently of the focus ring (twist the focus ring to check that it is indeed free, as this should now not affect focus).




5. Ensure the focus ring is set to infinity, then twist the barrel a fraction and check focus on a far off subject on the horizon. Tighten one of the retaining screws and recheck focus.

6. Repeat #5 until the sharpest focus is obtained.

7. Reassembly is the reverse of the steps above