Borrowing lens from friend and need help understanding how the camera settings affect the fixed aperture. Using a Canon Rebel XT digital
2006-09-20 08:04:33 · 6 answers · asked by Smiller 1 in Consumer Electronics ➔ Cameras
Are you sure it's fixed and not an auto. If it's fixed the capture or shutter speed will have to vary to accomodate changes in light intensity.
2006-09-20 08:08:41 · answer #1 · answered by fstopf4 4 · 0⤊ 0⤋
First you need to understand what Aperture is, the Aperture is the opening that controls the amount of light that is let into the lens. A lens that is 2.8 is great. Most lenses are 3.5 to 5.6 basically meaning when ever you zoom in with the lens the hole gets smaller therefore the image gets darker. Just remember this the lower the number of the aperture the bigger the opening. Aperture also effects what is called depth of field. It would probably be best to read a book or this site here can help you understand photography better. www.kenrockwell.com
2006-09-20 16:35:23 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Perhaps you mean a lens with a *constant* f/2.8 aperture. Like the Canon 17-55mm. Or the 70-200mm. And if that's the case, you're about to get your hands on a $1000-$1700 lens.
Don't worry though, there's absolutely no need to use them differently. 'Constant f/2.8' simply means that you can set the aperture as low as 2.8 throughout the zoom range. With cheaper lenses, you're usually limited to 3.5 at the wide end of the zoom and 5.6 at the far end.
So you get that, and you can expect better image quality and faster auto-focus.
2006-09-20 17:37:18 · answer #3 · answered by OMG, I ♥ PONIES!!1 7 · 0⤊ 0⤋
fixed at f2.8? never heard of such a lens. Is the aperture mechanism broken?
Try it on Aperture priority automatic (Av), and set the aperture to f2.8. The camera should function perfectly, as it believes that the aperture is F2.8, which is exactly what it is.
2006-09-20 15:12:10 · answer #4 · answered by Morey000 7 · 0⤊ 0⤋
I have never heard f a fixed apperture lens. It may be a fixed lens (no zoom - just one focal distance).
A F2.8 lens is a very good lens. If it s a FD Canon lens, you will need a FD to EOS converter.
If it is a fixed apperture lens, you will need to set your camera to apperture priority so that the light is metered by the camera and the shutter speed is adjusted.
2006-09-20 15:19:08 · answer #5 · answered by Rustom T 3 · 0⤊ 0⤋
If the lens actually fits your Rebel, you probably don't have to do anything different from what you have been doing in the past. you may have to switch out of full automatic into program mode and adjust the iso rating if you want a different shutter speed than full auto selects
2006-09-21 11:43:10 · answer #6 · answered by curious george 5 · 0⤊ 0⤋