At what distance from the collecting lens should the object be placed in order to obtain:

At what distance from the collecting lens should the object be placed in order to obtain: 1. an enlarged real image. 2. Reduced actual image. 3.Manual image. Choose the answer option from the suggested: a) between the focus lens. b) between focus and double focus. c) behind double focus.

The image produced by the collecting lens changes depending on how the distance between the object, the lens and its focus changes:

If the distance to the object from the lens and the focus of the lens are equal (i.e. the object is in focus), then the image will be at infinity (there will be no image).
If the subject is located behind the focus, then the image is upside-down and enlarged.
If the object is located between the focus and the lens, we get an enlarged direct virtual image of the object.
If the subject is located behind the point of double focus – we get a reduced actual inverted image.
If the subject is located between the points of double focus and focus – we get a real reverse magnified image of it.