Affect vs effect use [closed]

Question

I am tangled with the problem of using affect /effect.

In an experiment,

The defocusing of projector lens blurs the projected images that are projected onto an object.The projected images are used to generate the shape of the object using a method X.

Now I want opinion regarding these cases

1. Projected images are effected/affected by defocusing

2. The defocusing of images further effects/affects the method X.

3. The method X is effected/affected by defocusing.

4. The defocusing of projected images further effects/affects object's shape.

Answer 1

From Cambridge:

affect (v): to have an influence on someone or something, or to cause a change in someone or something

effect (v): to achieve something and cause it to happen

So, I would say you should use affect in each of your examples:

Images are affected by defocusing.

Defocusing affects images.

Defocusing affects image's shape.

Method is affected by defocusing.

You could use effect in a sentence such as the following:

Defocusing effects (that is, brings about or causes) the desired fuzziness in the photographic image.

Answer 2

In your use case scenario:
Affect is a verb: "Doing X will affect Y."
Effect is a noun: "The effect of doing X can easily be seen in the change in Y."

An easy exercise for learning the different use cases would be to replace these homophones in the following way to see if they make sense:

Replace "affect" with "cause a change in": Doing X will cause a change in Y. Replace "effect" with "result": "The result of doing X can easily be seen in the change in Y."