Why is my picture so much darker when I zoom in?

[kees.duif]

I notice that my A1 produces a much darker picture when I zoom in. Is that normal or is that because of a faulty setting?
Ofcourse I can turn up the gain but than my picture is to bright when I zoom out. Is there a solution for that problem?

 

[Huy Vu]

The simplified answer is that the iris closes as you zoom in. A1 is about f1.6 at the widest end and closes to f3.4 when you zoom in; less light ends up going through and the image gets darker. This is common across all lower end lenses on cameras at this price range.

 

[NonFiction]

The solution for the problem is to shoot in manual or aperture priority, and set the aperture at (or smaller than) the maximum aperture when the lens is zoomed--f/3.4.

That's your maximum full-zoom-range aperture. Use it and the exposure will not change when you zoom.

 

[Lloyds]

The solution for the problem is to shoot in manual or aperture priority, and set the aperture at (or smaller than) the maximum aperture when the lens is zoomed--f/3.4.

That's your maximum full-zoom-range aperture. Use it and the exposure will not change when you zoom.

Thanks for that NonFiction. I have had that same question for a while, and I appreciate you sharing that simple answer.