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11-03-2011, 06:37 AM   #1
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fast lens question

I am looking for a fast prime lens for indoor sports photography where flash is not permitted. My first choice would be a FA* 85 1.4 but I can't afford it right now. My question is how much difference will I see in light gathering between the F or FA 50 1.4, the FA 50 1.7 and the FA 77 1.8. Thanks in advance for the advice.

11-03-2011, 06:50 AM   #2
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f1.4 to f2 is a full stop, so to 1.7 it is a half stop to 1.8 2/3 of a stop. for sports all those lenses are pretty short for getting in close.
full f stop jumps are
F1, F1.4, F2, F2.8, F4, F5.6, F8, F11, F16, F22, F32, F45, f64, f90, f128....

the wiki on it is quite easy to understand actually

QuoteQuote:
In photography, stops are also a unit used to quantify ratios of light or exposure, with one stop meaning a factor of two, or one-half. The one-stop unit is also known as the EV (exposure value) unit. On a camera, the f-number is usually adjusted in discrete steps, known as f-stops. Each "stop" is marked with its corresponding f-number, and represents a halving of the light intensity from the previous stop. This corresponds to a decrease of the pupil and aperture diameters by a factor of \scriptstyle \sqrt{2} or about 1.414, and hence a halving of the area of the pupil.

Modern lenses use a standard f-stop scale, which is an approximately geometric sequence of numbers that corresponds to the sequence of the powers of the square root of 2: f/1, f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22, f/32, f/45, f/64, f/90, f/128, etc. The values of the ratios are rounded off to these particular conventional numbers, to make them easier to remember and write down. The sequence above can be obtained as following: f/1 = \frac{f/1}{(\sqrt{2})^0} , f/1.4 = \frac{f/1}{(\sqrt{2})^1} ,f/2 = \frac{f/1}{(\sqrt{2})^2} , f/2.8 = \frac{f/1}{(\sqrt{2})^3} ...
Also you have to take into account how narrow DOF gets when you use fast lenses at 1.4-1.8 in close nailing focus in action shooting will be tough. most sports shooters use a constant aperture Zoom say a 70-200 f2.8 which would be a little over a stop slower than an FA77 but let you frame better (and will mean moving from iso 800 to iso 1600 for instance (or 1600-300, 3200-6400..... hence the value of a K5)

EDIT: I see you shoot with a K7 so i understand why you might want the extra bump at the lens as you already have a 2.8 70mm. your long lens though is quite slow. a Tamron 70-200 2.8 and shoot at 1600iso on the 7 with some judicial noise reduction may result in more keepers than an FA77 @1.8 (lots of other reasons to want an FA77 though, just not for sports IMO)

Last edited by eddie1960; 11-03-2011 at 06:58 AM.
11-03-2011, 06:51 AM   #3
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I would not use apertures below 2,8 for sport. I believe the AF would have a lot of problems to keep the thin DOF on swiftly moving subject. Actually I hold the FA*85 as a fast focusing lens and I've done some nice BIF shots with it, but I always stopped down to at least f2.8.
11-03-2011, 06:55 AM   #4
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QuoteOriginally posted by jkglogau Quote
I am looking for a fast prime lens for indoor sports photography where flash is not permitted. My first choice would be a FA* 85 1.4 but I can't afford it right now. My question is how much difference will I see in light gathering between the F or FA 50 1.4, the FA 50 1.7 and the FA 77 1.8. Thanks in advance for the advice.
what sport and how close?

Remember

Image size = subject size x focal length / distance.

I have shot Tae-Kwon-Do with a K50/1.4 and and had great results, but this is ring side. MF is not as hard as it sounds, and lighting is constant indoors, so once you get exposure set, just shoot in manual.

bump the ISO as high as possible, and trade ISO for Aperture and shutter speed to get the DOF and stop action shutter speed you want.

don't get bent out of shape with grain, it will be there,

11-03-2011, 07:46 AM   #5
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Don't get the FA 77mm for sports. As much as I love the lens and love the focal length for gym sports, the AF simply can't keep up.

I disagree with the f2.8 recommendation, too. I shoot the FA 50mm f1.4 around f2 and get decent results. You'll definitely miss some shots to DOF, but you're always going to miss some shots in sports to one thing or another. I just try to keep the center focus sensor on the players' numbers and shoot a lot. If you shoot the same team enough, too, you'll even learn how they play and will be able to follow the action better. You'll know who's going to pass and who's going to shoot and when.

Despite what I said about the FA 77mm, here's a shot I did with it before I switched completely to the FA 50mm f1.4 for basketball:


Flickr Link

Like most photographic genre's, practice is the best way to improve. Good luck!
11-03-2011, 07:59 AM   #6
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Have you considered the Sigma 85mm 1.4? By nearly all accounts, it has outstanding image quality and focuses very quickly and silently. I hope to own one of these sometime after the holidays to use at my daughters' ballet recitals.
11-03-2011, 08:00 AM   #7
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QuoteOriginally posted by GhoSStrider Quote

I If you shoot the same team enough, too, you'll even learn how they play and will be able to follow the action better. You'll know who's going to pass and who's going to shoot and when.



Like most photographic genre's, practice is the best way to improve. Good luck!
2 very valuable insights for sports. most of my sport shooting was in school and manual focus so knowing the game and the teams general play style allowed me to get shots. I shot hockey with a tak 55 1.8 frequently and missed a fair bit on dof, but knowing the team meant i still got more than enough good shots (and i shot way less than i would now on digital, film cost money even when you rolled it yourself. I also usually shot at 2.8 and picked a zone to predict play, more keepers that way
I still stick by the zoom idea for most sports now though. it's convenience i think outweighs the one stop light loss (unless of course you can be in close like ringside at a sport like Lowell mentioned. )
11-03-2011, 01:37 PM   #8
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You already received some good advice. I think that it is important that you assess how far you will be. I shoot often volleyball and I can easily approach close to the lines. In that configuration, I favour 50 mm to 90 mm focal length. If you are further away, you will need a longer reach. Another important consideration is the amount of available light. If the hall is well-lighted you mihgt be able to shoot at f2.8. In poor light conditions, you will need to increase the aperture to f1.8 or f1.4 to keep a fast shutter speed.

More generally, in por light conditions, you should consider seriously to shoot MF. It is not easy off course, but a good trick is to use the focal distance on the focal ring as an indicator. For example, a volleybal court is 9m by 9 m and I can work out easily the distance between the player and myself. Combining a MF operation with hi continuous shooting, I got some great shots.

As I often shoot in poorly lighted halls, I tend to use MF lenses preferentially, largely because their focus ring is much much smoother and precise than most AF lenses.

Hope that the comment may help.

11-03-2011, 02:36 PM   #9
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A cheap solution would be to put a 1.4x or a 2x and turn it into a 70 f/2 or 100 f/2.8.
11-03-2011, 02:47 PM   #10
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Sigma 85mm f/1.4. Fast AF. Sharp even wide open. Equiv. to a 135mm lens which is often used for indoor sports on a FF body.
11-04-2011, 07:20 AM   #11
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thanks for all the great advice. The sport I am trying to shoot is my son speed skating in a poorly lit rink (on wheels, not ice). I tried the K7/ Tam 70-200 2.8 and got almost no keepers. I was hesitant to push the ISO but now have noise ninja so I will try a faster speed and see how it works before investing in a fast prime. I just bought a new computer so I am now short on cash for a while. Cheers!
11-04-2011, 09:09 AM   #12
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Since you know (roughly) where he should be on the rink, your life just got a lot easier. Pick a spot on the rink, set the camera to manual focus, and then fire when he gets there. Try to set up so that he's coming towards you if possible. You won't need as high of a shutter speed as if you were shooting lateral motion. The toughest part will be to learn when to shoot to get him in focus. All you can do for that is to practice.

Additionally, since the motion is fairly predictable, try doing a pan or two. They take a little practice, but they'll let you use lower ISOs since you'll *want* slower shutter speeds. Good luck!
11-05-2011, 12:53 AM   #13
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QuoteOriginally posted by GhoSStrider Quote
Since you know (roughly) where he should be on the rink, your life just got a lot easier. Pick a spot on the rink, set the camera to manual focus, and then fire when he gets there. Try to set up so that he's coming towards you if possible. You won't need as high of a shutter speed as if you were shooting lateral motion.
Another trick to play here: CIF (catch-in-focus). Make sure you have CIF enabled in the [Custom] menu. Set the camera to AF.S, not MF. Prefocus on a selected spot on the rink. Hold down BOTH the lens-lock release button and the shutter. When he approaches and comes into focus, the shutter will SNAP and you've got the picture.
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