Crop lens
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For a crop sensor camera, ie lens won't cover full fx frame.
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A circular lens projects a circular image.. if the circle doesn't cover the full sensor you will get vignetting in the corners. Lenses with smaller image circles can be made lighter and/or cheaper. But these lenses don't have a large enough image circle to completely cover a full-size sensor.
On top of that, you can get differences in the mount that mean that some lenses for crop sensor cameras sit further back in the throat of the mount and interfere with the mirror of a full frame camera built to a slightly different mount specification.
You can see the vignetting effect in this shot (look at the corners)..
It's the same effect you would get if you mounted a crop-sensor lens on a full-frame sensor (slightly different set-up here). The image circle of the wide-angle lens is smaller than the image capture area. The corners are left unexposed. Ignore the black bars on the sides, that's a different problem.
On top of that, you can get differences in the mount that mean that some lenses for crop sensor cameras sit further back in the throat of the mount and interfere with the mirror of a full frame camera built to a slightly different mount specification.
You can see the vignetting effect in this shot (look at the corners)..
It's the same effect you would get if you mounted a crop-sensor lens on a full-frame sensor (slightly different set-up here). The image circle of the wide-angle lens is smaller than the image capture area. The corners are left unexposed. Ignore the black bars on the sides, that's a different problem.
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^^^ Yes.
The advantage of a lens for crop format (eg Nikon DX or Canon EF-S) is that if the image doesn't have to fill such a large sensor area, the designers can do more.
Eg, Nikon DX kit zoom 18-55mm f/3.5-5.6 costs about £100, whereas in FX the closest is 16-35mm f/4 and it costs nearly ten times more. That's not quite a direct comparison, but you get the idea. These optical advantegs run out quite quickly with longer focal lengths so you don't see any long DX or EF-S lenses.
The advantage of a lens for crop format (eg Nikon DX or Canon EF-S) is that if the image doesn't have to fill such a large sensor area, the designers can do more.
Eg, Nikon DX kit zoom 18-55mm f/3.5-5.6 costs about £100, whereas in FX the closest is 16-35mm f/4 and it costs nearly ten times more. That's not quite a direct comparison, but you get the idea. These optical advantegs run out quite quickly with longer focal lengths so you don't see any long DX or EF-S lenses.
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Yes. Nikon DX has a crop factor of 1.5x relative to full-frame. Same as Sony. Canon croppers are fractionally smaller at 1.6x. Micro Four Thirds (Olympus, Panasonic) is smaller still, with a 2x crop factor.
Crop factors are mainly used to get equivalent focal lengths, compared to the old 35mm film format (which is full-frame, 36x24mm - confusing isn't it!). To get the sensor area difference, you have to square the crop factor, eg 1.5x1.5=2.25, which means a DX sensor is just a bit less than half the area of full-frame.
Hope that's clear! LOL
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You have a crop sensor, all lenses are the same.
I think lol
I think lol
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WOW thanks, I asked for it and boy I got it.
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DX and FX are different.
DX lenses are designed to be used on DX (ie cropped) sensors although you can use them on FX bodies and you can use FX lenses on DX bodies :bang:
This explains it quite well, and better than I could as it has diagrams
http://www.nikonusa.com/Learn-And-E...hnology/g588ouey/1/The-DX-and-FX-Formats.html
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DX and FX are different.
DX lenses are designed to be used on DX (ie cropped) sensors although you can use them on FX bodies and you can use FX lenses on DX bodies :bang:
This explains it quite well, and better than I could as it has diagrams
http://www.nikonusa.com/Learn-And-E...hnology/g588ouey/1/The-DX-and-FX-Formats.html
Thanks for that, it was explained more clearly.
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BEWARE of using EF-S lenses on FF Canon cameras as you will damage the mirror because the EF-S lenses protrude more at the back and can only be used on crop cameras.
I'm not sure whether they can be used on Canon cameras which have 1.3x crop bit I'm sure someone else on here can advise on that.
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I'm not sure whether they can be used on Canon cameras which have 1.3x crop bit I'm sure someone else on here can advise on that.
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EF-s lens (which have a white square to line up against the body, as opposed to red circle) wont fit either 1.3 or FF Canon cameras, neither will they fit 10d (or earlier) bodies. Some have been modified but they risk hitting the mirror as it swings on non crop body, that isnt an official Canon recognised mod, its rare to find one.
35mm is in fact 36x24 not the dimensions stated above (picky I know)
Matt
35mm is in fact 36x24 not the dimensions stated above (picky I know)
Matt
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Oops, my typo. Yes 35mm film has an image area of 36x24mm - I've corrected the post above.
35mm is in fact the width of the film, hence the name.