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I am learning photography .. P. I have a Canon 20x optical zoom and a Nikon SLR D3000 W / 200 Telephoto,?
Why my canon zoom less than my Nikon SLR with tele 200? My Nikon camera is better and faster shutter was disapponted but I can not get close enough telephoto55 with my Nikon 200 mm lens, I can do with the fixed 20x Canon optical zoom? Pls help educate me! 
Gerald is wrong by a mile ignore that one. Well, first things first, ditch the idea of the optical zoom or factor X. That does not apply to dSLR in most cases. It is used in the covenants by the wide end, usually around 25-30mm is usually the focal distance for all covenants, regardless of price or brand, so the idea of saying 3x zoom works well. dSLR lenses are changed out and the final changes in width, so you may not do likewise. For example. Let's say you have a little compact digital camera that says a 5x optical zoom on it. What it really means is that the focal length is five times more on the longer end than the wide end. Let's say that the wide end is 25mm. So the maximum focal length is 125mm. So the lens numbers will look something like this with a 25-125mm f-stop number thereafter. That's where 5x wine. I have a 80-200mm f/2.8 zoom lens on my dSLR. If you use compact digital camera thought, is something of a 2.5x zoom. But you can get beyond covenant that purports to be 5 times because I have 200 mm in the long end, the compact only 125 mm. You see it does not work because the wide end changed everything. To complicate things worse, you have to deal with the size of the sensor. The reason for his long-range zoom canon even more is that it has a tiny sensor, you can use small glass, to get to achieve. The Nikon DSLR image sensor has a mass, you probably have 8.12 times the size of the small canon. The larger the sensor, higher the glass should be to achieve the same purpose. If someone made a lens for your Nikon dSLR that matches the scope of the pipe, it would be so great that I never want to take, and so expensive than ever could afford. It's only a matter of physics that can not be changed. That's why 2010 is now seeing the photographers at football matches with, expensive, huge lenses, they need that to get the scope. To make matters worse, dSLR image sensors need large glass top, also because the sensors are even greater than what you have in your Nikon. But that's why dSLR will rule when it comes to photography in low light. sensors larger image with more pixels large gathering much more light than the super tiny sensors with microscopic pixels found in the covenants and megazooms. So I did not know, but you know. I Here is a picture to give you a better idea. The smaller square in the middle is what is in their long zoom Canon. My dSLR and yours is much larger APS-C call. The largest is full frame, these are only found at the upper end dSLR, very expensive. Cheapest FF sensor for the Nikon D700 costs around 3000. More FF Sony is cheaper A850, $ 2,000. http://en.wikipedia.org/wiki/File:Sensor_sizes_overlaid_inside.svg
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