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07-17-2012, 06:31 PM   #1
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Zooms and telephotos for sports

It has been absolutely flooding outside for about 2 weeks straight so I have not been able to go and actually do the measurements. None the less, I did a rough calculation and if anyone knows the real numbers please post them up.

I have been contemplating getting a good zoom but I have to take many things into account when doing so...so I decided to list them here and get input or other ideas that I may have missed.

I have calculated out that at 'about 30 yards' (based on my scientific guestimation of pacing off the distance) one can photograph the full body of a 6 foot tall person and get their whole body in the frame with 200mm lens at full zoom. For sake of argument lets say you had a big 6 foot blue dot as your target... at 30 yards and beyond you can get it in the frame with a 200mm lens.

With a 300mm lens this distance increases to about 50 yards (again educated guessing until I can measure it for sure).

400mm and 500mm I do not know the numbers...but would be curious to know.

There may be some formula to figure this stuff out...but I don't know it.

Long story short with a 200mm lens if you were on the sidelines of a football game you could get some decent shots as the field is 50 yards wide. Hence a 70-200mm would be sufficient for 'most' things if you could get down on the turf so to speak...if you were shooting someone on the far sideline at an angle you might not get the shot you want as you might need a bit more stretch. Something that goes to 300mm would cover the width of the field and that is standing on the sidelines....

Second thing is aperture. If you are shooting indoors in funky lighting or so forth you want to have large apertures. Generally f2.8 is what you will get if you can find it in the right focal lengths. Concerts, weddings and so forth might also be served very well by the currently available f2.8 zoom lenses.
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In other words I have a choice to make, and odds are I will end up choosing more than one, but man, those things are expensive!!!

It looks from all accounts that I will 'need' more than one zoom. Right now I am eyeing two zooms.

the tamron 70-200 f2.8 which would take care of my indoors lower light stuff...but doesn't have a whole lot of stretch to it when it comes right down to it.

the second option which I also find very attractive is the sigma 50-500. I live in the country with about 250 square miles of forest surrounding my house. The reach is very attractive. One of the questions I do have is how would this lens perform under less than optimum lighting? I love hockey so I go to games a lot. I would be shooting from the stands...same with baseball...

Indoors, under those types of lights what kind of shutter speeds can you hope for with this lens?

I should also mention that I like polo (no I am not rich) but its very fun to watch and very photogenic. Polo is played outdoors in the sunshine so I am less worried that I could get sufficient lighting to make the 50-500 beast work....

Realistically since I probably won't be getting press passes to sporting events would I be wrong in saying that for professional sporting events (unless I get really good seats) the 70-200 range will be for basketball or the prime seats...it would also be PERFECT for my true love of waterskiing.... it would be a perfect zoom for that specfic sport...

The 50-500 will be for my usual 30 rows up seats...or doing some outdoors stuff...

The 70-200 would be for weddings and anything else like that...

For those who are in the know, I am wondering what kind of shutter speeds you can realistically get with a sigma 50-500 lets say at full zoom in various lighting situations... (bright sunshine all the way to say indoor baseball games)....

I am trying to make an educated choice here so any help would be appreciated. Experimenting is quite expensive....buy a lens based on reputation and what happens if you don't like it? I wish there was a try it before you buy it possibility but alas, not so (that I know of)....

If I was really wanting to get out and shoot field sports I don't see any way around going with the big 400mm or 500mm jobs with big apertues... all I know is those are out of my price range...

07-17-2012, 07:20 PM   #2
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QuoteQuote:
There may be some formula to figure this stuff out...but I don't know it.
If I understand you correctly you could take the FOV listed in the lens specs (for relevant sensor size) and then use trigonometry.

I think the formula is something like this:
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07-17-2012, 07:27 PM   #3
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I use a Sigma 100-300/4 for field sports and a 50-150/2.8 for basketball (but I don't do math ;~)
07-17-2012, 07:39 PM   #4
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QuoteOriginally posted by Chaos_Realm Quote
If I understand you correctly you could take the FOV listed in the lens specs (for relevant sensor size) and then use trigonometry.

I think the formula is something like this:

It makes sense except for the trigonometry part.

07-17-2012, 07:42 PM   #5
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QuoteOriginally posted by dadipentak Quote
I use a Sigma 100-300/4 for field sports and a 50-150/2.8 for basketball (but I don't do math ;~)
I have the 55-300mm zoom already. Its pretty darn good in some respects. But I have the disease. If I don't keep on buying lenses I won't know what to do.

I do want the zooms but I don't know what to buy... so far the 50-500 looks very appealing but I want to know more about it... ie the light test.
07-17-2012, 08:17 PM   #6
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QuoteOriginally posted by alamo5000 Quote
tamron 70-200 f2.8 which would take care of my indoors lower light stuff...but doesn't have a whole lot of stretch to it when it comes right down to it.
The 70-200 2.8 zooms are really the work horses of many pro sport/wedding photogs from what I understand. Good IQ and relatively fast max aperture.

QuoteOriginally posted by alamo5000 Quote
also find very attractive is the sigma 50-500
I personally have the 150-500 OS HMS it is a really nice lens, for the price, but fast it is not! I have difficulties using it on my K-7 as I limit my ISO to about ISO1200 due to high noise (IMO) when I am out birding. The K-5 I have heard is a whole different kettle of fish with good ISO up to 6400. Currently your options are quite limited other than the sigmas when using k-mount at the super-telephoto end (except when collecting legacy glass which is hard to find)

Most pro sports shooters when shooting indoor/night football matches will have something in the 400 F2.8 or F4 ballpark if that gives you an idea of what gets used. IE very expensive lenses.

QuoteOriginally posted by alamo5000 Quote
I am wondering what kind of shutter speeds you can realistically get with a sigma 50-500 lets say at full zoom in various lighting situations... (bright sunshine all the way to say indoor baseball games)
Some examples from shots I have taken with 150-500 OS @500mm
Bright sunshine = ISO 1250 1/1000s F10
Shade = ISO 1600 1/500 F8
Dull Overcast = ISO 2000 1/160s F8
Indoors Good light = ISO 1250 1/60 F6.3
Indoors Poor Light = ISO 6400 1/10 F7.1

But this is going to be pretty much Identical for any lens you get. the only difference is that when using longer lenses camera shake is amplified.

As for the trigonometry basically you just need to substitute appropriate values in for X,Y or Theta(FOV) then solve for the unknown. I have attached a bit of a maths lesson for this type of question.
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