Nikkor f/1.1 LTM Lens: Replacing a Damaged Diaphragm Blade
Originally posted on Instagram. Notes from the repair bench, kept here as a searchable archive. View the original on Instagram
Nikkor f/1.1 LTM Lens Repair. I did this repair a while ago and image quality is not the best but will post it now because it is an interesting lens. When noticing these lenses for sale, I often can see in the photo (or described) that one or more of the diaphragm blades are damaged or outright missing. Or the diaphragm has a non-round shape. The reason for this is because the diaphragm blades, as you can see in the photos, are boomerang shaped with a thin middle section. When a bit of oil contamination reaches the blades, this extra friction will cause the fragile blade to twist and become damaged.
In the case of this lens, I installed a new blade that I had in stock. Putting the blades back into this lens was a bit of a chore since there were twelve blades and the blade ring was curved! I’m glad I no longer have the blades available as this was a time consuming repair. Also, I have found it common for the element group in the rear to separate at the point shown in the photo. This takes a specialist to re-cement so I sent that part out for service.
