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View Full Version : difference between 3X optical zoom and 10x optical zoom



sreenivasan2711
01-15-2005, 11:50 AM
Sir,
I want to know the difference between 3x optical zoom and 10x optical zoom. also if a 10x camera and a 3x camera are fixed at the same distance from an image the picture from which one will be better.what difference will each one cause on the image shooted

sreenivasan g

kgosden
01-16-2005, 10:58 AM
Hmm, I am having a bit of difficulting following your questions, but here goes.

Optical zoom mulitples (3x, 5x, 10x, etc) all refer to the difference between the widest angle (smallest lens mm value) and the longest telephoto setting. So for a lens that starts at 30mm a 3x zoom will result in a 90mm telephoto focal length (all in 35mm film camera equivalents). A 10x camera with a 30mm wide angle will have a 300mm telephoto end. Since the 'x' is relative to the wide angle of a given camera you cannot use that as the only comparison between two different cameras. Of course, that is not really true when comparing a 3x to a 10x, but is certainly true when looking at cameras with similar 'x' multiples (3x and 4x for example).

In general, digital cameras tend to have wide angle focal lengths startinf around 35mm. For most 3x or 4x cameras this limits the maximum telephoto to the 105-150mm range. This is a good portrait focal length in traditional film cameras as it let's you take a nice head and shoulders shot from 5-10 feet away from your subject. That distance gives most people a bit of personal space and lets them feel at ease when being photographed. 150mm is not really much of a telephoto for what most people consider the 'zoom' factor; bringing far subjects in close. A picture of a sporting event from 50-100 feet away will still look distant. The image will probably seem very similar to what your brain and eye were able to isolate. You will not experience the sense of being closer to the action. for that you really need to get into the 200mm or higher telephoto range.

As for which will be 'better', that is hard to say as you did not define what would be a better picture for you. If you mean higher quality image, then you might need to look at the lens quality and the pixel count of the camera. A 3x zoom on an 8 megapixel camera might have a better final image than even a 10x on a 3 megapixel camera. But the opposite might not be true if the lens or camera's imaging system are not very good.

ktixx
01-16-2005, 12:19 PM
In addition to the information previously posted, Optical zooms, where there is moving glass inside the lens does not cause any degradation in picture quality (minimal if any), however digital zooms significantly reduce the quality of the image. With an optical zoom it is similar to using a magnifying glass to view a small object, with digital zoom it is similar to taking a picture of the image, then streching it out. The increase in optical zoom will not decrease the quality significantly enough that you will notice , however the more zoomed in you are on an immage the harder it is to keep the camera steady. Camera shake will cause the pictures to be slightly blurry. When purchasing a camera just pay attention to the optical zoom, the digital can be done on you computer. The greater the zoom = the more flexibility in the camera, if you don't want to zoom in 10x then you don't have to.

sreenivasan2711
01-17-2005, 02:58 AM
thanks a lot for ur valuable information. i have one more doubt.suppose i have a 3x optical zoom digital camera.can i increase the optical zoom by adding extra lens to the camera later?

judge9847
01-17-2005, 03:55 AM
To help, have a look at some images I posted to this thread (http://www.dcresource.com/forums/showthread.php?t=1216) some time back.

They were taken with my FZ10 - which has the same lens as the FZ20 - and they show the same thing at zero zoom, the full 12X and then, just for the heck of it, the 12X optical with 3X digital thrown in.

That's the sort of difference the lens can make.

As for adding a converter lens to a 3X zoom, I'm not sure that any camera like that can handle one. Some might but it's difficult to imagine how they might be fitted. But I've no doubt that you're asking the question on the right site. If it can be done, there's someone here who will be able to tell you how to do it.

David Metsky
01-17-2005, 06:04 AM
thanks a lot for ur valuable information. i have one more doubt.suppose i have a 3x optical zoom digital camera.can i increase the optical zoom by adding extra lens to the camera later?
Some do, but they have to be designed to do so. The Canon A75, A85, and A95 all take a series of wide angle and telefotos add-on lenses. So does the Sony W-1. I'm sure there are others as well.

sreenivasan2711
01-17-2005, 08:26 AM
really u people's answers are helping me a lot. i have one more doubt.Is there much difference between a 4 mega pixel camera and a 5 mega pixel camera.also if i want to take the printout of images from both of A3 size will there be much difference in there quality

ktixx
01-18-2005, 09:35 PM
When printing the images you captured (up to 8x10) there really is no difference between a 4 and 5 MP camera. The major difference comes when you crop. If you do a lot of cropping you may want to invest in a higher MP camera.
Ken