Sharp/Fast Wide Angle for a FF sensor

Got an assignment that I would like some advise on. I'm putting in a Soccer Goal Camera, on a poll (2 ft behind the net). I was going to use a 85mm f/1.8 on 1Ds Mark II with a Bogen SuperClamp and PocketWizard.

I am finding that the 85mm just might be too long, something shorter would be preferred. Although I have an arm so that I can actually put the camera behind the poll as well. Also, there is some vignetting going on with the 85mm and FF sensor.

So options:

1. 85mm f/1.8 on the arm and just pull it back further (poll being visible might be a problem, so will slippage using the arm)
   
2. 24mm f/1.4L I or II
   
3. 50mm f/1.4
   
4. 16-35mm f/2.8

If you need to cover the whole net, (post to post) the 85 is going to be way to long, imo.

The way you are describing it, I think you'd be looking at something < 20mm on a FF.

16-35 should cover it nicely.

Hmmm I do have a 14mm as well, its a bit of fishy output but it can be flattened in photoshop pretty well, maybe that's a better choice.

how about the 17-40mm ? canon's most popular lens
tremendous results

What about the 24-70? You are using on a FF camera. Then you could get the shot perfect.

aram535 wrote in post #7970102
Hmmm I do have a 14mm as well, its a bit of fishy output but it can be flattened in photoshop pretty well, maybe that's a better choice.

The 14 would be wide enough, probably too much so. I would go with the versatility of a zoom, since you would be less pressed if having to change the location of the lens.

The 17-40, mentioned would be a good, less expensive, alternative .

I'd say the 16-35 or the 24-70 would be the best two options.

24L or the 16-35L, IMO. You can't shoot at f/1.4 anyway since the DoF will be too shallow. So f/2.8 would be a good minimum. The 50/85mm lenses will be too long that close to the net.

The longest lens that will encompass the whole of the goal mouth (8' x 24') from 12' behind the line (10' net + 2' additional) is about 18 mm for FF. The required AoV is 90°.

The only one on your list that will do the job is the 16-35.

xarqi wrote in post #7971401
The longest lens that will encompass the whole of the goal mouth (8' x 24') from 12' behind the line (10' net + 2' additional) is about 18 mm for FF. The required AoV is 90°.

The only one on your list that will do the job is the 16-35.

Well there you have it.... A definitive exact calculation. Impressive. Thanks

BTW. I love your Vent...we have a similar problem in the office with people confusing affect vs. effect. Oh and ensure vs insure.

I don't think the Net is 10' deep, more lke 3' and the poll is only another 6"-10" back. That doesn't change your calculation a whole lot, but just to note it.

I don't know the DoV of the 14mm but it can't be much more than the 16mm, no? The only reason I'm thinking the 14mm is that I already have it, where as the 16mm or 17mm lenses I would have to rent. They're not much less than $100 for a 7 day rental.

aram535 wrote in post #7971554
I don't think the Net is 10' deep, more lke 3' and the poll is only another 6"-10" back. That doesn't change your calculation a whole lot, but just to note it.

I looked into that. The standard size for a soccer net is usually given as 24 x 8 x 10 x 4, which, by my reckoning, puts part of it in hyperspace! It turns out though that it's 4' deep at the top, and 10' at the bottom.

It sounds like your situation may be different, but if you have exact figures, then an exact calculation can be done.

The first step is a bit of trigonometry. Given w, the width of the goal, and d, the distance of the camera behind it, the required horizontal angle of view is:
2 x arctan(w/2d)

(Unless the goal mouth is an odd shape, the vertical aspect should be OK).

Armed with that, head over to -->here<-- to pick up your handy AoV table (courtesy of 20droger) and see what fits.

P.S. I have assumed that the camera will be mounted halfway between the posts horizontally, and at half the height of the goal mouth vertically.