If focal length of the concave Mirror is determined by using convex lenses of different focal lengths, do you expect any change in the result? If yes, what type of change? If not why not?

Please answer the question

Dear student, We will not get any change until the difference between the focal length of both lens and mirror is not very high. But, normally we don't get any difference because if we will change lens of different focal length, we will adjust the frame system again such that we get all the parallax removed. So basically it won't affect the focaccia length of the mirror. Regards