Finder and camera using such finder

A camera comprising:

• a photo-taking optical system;
• and
• a finder, an optical axis of said finder being different from an optical axis of said photo-taking optical system, and said finder including an objective optical system which includes, from an object side to an image side, a first lens unit having positive power, a second lens unit having negative power, a third lens unit having positive power, and a fourth lens unit having positive power;
• and an eyepiece optical system;
• wherein, when zooming is performed from a wide-angle end to a telephoto end, said second lens unit is moved toward the image side, said third lens unit is moved toward the object side, and said fourth lens unit is moved such that an air space between said fourth lens unit and said third lens unit is changed.

A camera comprising:

• a photo-taking optical system;
• a finder, an optical axis of said finder being different from an optical axis of said photo-taking optical system, and said finder including an objective optical system which includes, from an object side to an image side, a first lens unit having positive power, a second lens unit having negative power, a third lens unit having positive power, and a fourth lens unit having positive power;
• and an eyepiece optical system;
• wherein, when zooming is performed from a wide-angle end to a telephoto end, said second lens unit is moved toward the image side, said third lens unit is moved toward the object side, and said fourth lens unit is moved such that an air space between said fourth lens unit and said third lens unit is changed;
• and
• a solid state image sensor for receiving an image formed by said photo-taking optical system.