Then how do I make the Camera take in more light at higher zooms? I need that big aperture but a higher zoom...
Unless you physically change the optics, the only way to collect more light is to use a longer exposure. Of course, unless you use a tracking mount, the length of exposure you can use before trailing becomes a problem is limited, and the higher the zoom, the shorter the limit. You can take multiple exposures below the limit and stack them to get deeper images, but this becomes impractical at high zoom because the minimum exposure is so short.
