Field Of View Crop Factor...

FOV and crop factor has been discussed extensively. Have you tried using the search function to find some threads on it?

If you still have some questions after reading them, feel free to ask again here.

It only matters if you come from a film background. If you come from a video background, or if you're just starting out, it's a non-issue. Photography people have a certain look that comes to mind when you mention a focal length. It will look different than they're used to on a 550D. If you don't already have a preconceived notion of what a lens should look like, it doesn't matter. EF and EF-S lenses will all work on the 550D (and look the same).

you should try figuring this out with a 35mm adapter. In theory its like having a full frame sensor, but you have to zoom in to get past the vignette which just screws the whole concept.

I did read a way to MEASURE your FOV to see what your really getting... I keep meaning to do it, but then I just film something instead.

For example, my 28mm vignettes worse than my 50mm so I zoom the 28mm in more, and end up with about the same FOV as the 50mm! Its definitely different "looking" and the background\foreground relationship is very different, but when it comes to FOV.. meh.. !


(ok, here is the info I mentioned ignoring http://www.panohelp.com/lensfov.html )

wheatgrinder said:

you should try figuring this out with a 35mm adapter. In theory its like having a full frame sensor, but you have to zoom in to get past the vignette which just screws the whole concept.

I did read a way to MEASURE your FOV to see what your really getting... I keep meaning to do it, but then I just film something instead.

For example, my 28mm vignettes worse than my 50mm so I zoom the 28mm in more, and end up with about the same FOV as the 50mm! Its definitely different "looking" and the background\foreground relationship is very different, but when it comes to FOV.. meh.. !


(ok, here is the info I mentioned ignoring http://www.panohelp.com/lensfov.html )

Click to expand...

I'm all for shooting test-footage, so normally I'd agree with you, but in this particular instance, there's not much of a point. An EF-S lens will look exactly the same as an EF lens of the same focal length, on a 550D. It's good to be aware of what's going on, cuz your DP might be accustomed to 35mm film look. But that has no bearing on the OP's question - buy the lens. It will fit, and it's compatible (I'm assuming we're talking about canon's nifty fifty, otherwise that changes things).

I am repeating some of the things Wheat and CF said but im writing this post to clarify the matter a bit.

So, you are in the market for a 50mm lens and you're worried that the crop factor on your camera wont give field of view of a 50mm lens. But which field of view are you comparing it to? A 50mm will give you different fields of view on different sensors. From your post, it seems do not have a benchmark for what a 50mm usually looks like to you as professional photographers do when they use full frame cameras. So don't worry about it. Get a 50mm for your camera and in the future when you want to go wider or longer, you'll have your own benchmark compared to what 50mm field of view is on a 1.6 crop factor sensor. (Besides an APS-C size sensor is close to S35 anyway. So you'd be getting used to what people in film making were/are used to.)

And don't worry about vignetting or zooming or anything. You can use an EF or an EF-S lens on ur 550D. The only difference is that the EF lenses are larger and cover more area than the 550D sensor. The extra image just gets cropped. The EF-S lenses are smaller and fit the 550D sensor better. But in the end both can be used just as well.
However, if you take an EF-S lens and later try to use it for a new camera body with a larger sensor (like the 5D) then you will get vignetting.

If all the information here and above is starting to confuse you even further, then dont worry about it. Just know that a 50mm EF or EF-S lens is fine for your 550D. You're not making a mistake by buying it. Go buy one and start using it.

Although the crop factor is less relevant if you're not used to shooting full-frame, it can make things a bit confusing for people - I've seen loads of people in different forums think it doesn't apply to EF-S lenses, and confuse themselves with calculations. If you can remember one fact you can forget most of that - a normal lens on FF is a 50mm, and on an APS-C camera is 30mm. That'll give you a good starting point around which to base your lens collection.

And by "normal" they mean roughly the same as a human eye. Place that lens, and your eyes the same distance from the object, and they have roughly the same FOV.

Wow, thanks a lot everyone! You've been a great help.

It was actually a photographer who mentioned the crop factor to me, so no wonder he got into a stink about it haha.