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[jookny21]

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[ktixx]

Your problem isn't a problem it is a reality. Point and Shoot Zoom lenses usually do not have consistent apertures (almost never). The more zoomed in the smaller the aperture. In addition, the smaller apertures are usually reserved for more expensive, an heavier lenses. Take a look at the Canon 70-200 f/4 - Roughly $600 or you could get the Canon 70-200 f/2.8 - Roughly $1100. The only real difference between these two lenses is the f/stop.
Your camera has a minimum aperture (widest aperture) of f/2.8-5.2 accross it's zoom. This means at the widest the lens's widest aperture will be f/2.8, at it's longest zoom the camera's widest aperture will be f/5.2. This is just how it is. If you wan't to have constant apertures you will have to move to a dSLR and invest quite a bit in lenses.
Hope this helps
Ken