I've lately been using my AF-S lenses on manual as practice, and here's my bonehead question: do you need to register a solid green light in the viewfinder to be in focus, or will a blinking green do as well?
To answer the unasked question, I don't intend to upgrade the body at this time, and there is a lens I want (Tokina 11-16 f/2.8) that doesn't auto-focus on the D40.
#1. "RE: D40 Manual Focus Exercise" In response to Reply # 0
There actually is not graded state where the focus indicator blinks. It is either in focus and the light is on or it is not in focus and the light is off. However, the focus system works really fast and this is what you are seeing when it seems to blink. Just the subtle movements of your hand and movement of the target can cause this blinking to occur. In some cases you may never be able to get it to come on solid.
#2. "RE: D40 Manual Focus Exercise" In response to Reply # 0
Not a boneheaded question at all.
In fact, some lenses will be much easier to use with manual focus than others: specifically, those which inherently have a lot of depth of field, like ultra-wide angle lenses. At typical shooting distances, the 11-16 produces very great DOF, so manually focusing is much easier than with some other lenses. You'll find that the green light blinks a lot less for this type of lens than with most other lenses.
_____ Brian... a bicoastal Nikonian and Team Member
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