jbmauser Loc: Roanoke, VA

Thanks RobR. I had read to use shutter speed of 1/2000 for BIF but your data seems more reasonable. I have the Tamron 150-600mm.
When you said you tuned the focus of your Sigma what are you referring to, Back focus?

Also do you set it to Auto ISO?

Jim Bob

First, analyze by focusing on a stationary subject with the use of a tripod if available. Let us know your results.

Zeke4351 Loc: Kentucky

For sports photography I set my shutter to at least 350 and the fstop 8. Then I set my camera to auto ISO and focus in C mode. You will see a big diference.

Howard5252 Loc: New York / Florida (now)

You have gotten lots of advice ... I didn't read it all so at the risk of repeating
1- The problem is probably you, not your equipment.
2- Fast indoor sports is difficult to shoot (you were told this one).
3- Read the owner's Manual, Here is the trick to this one. Pick one topic at a time and practice before moving to another. For instance, try reading about the use of the focusing points. Learn it at least to the point of knowing how to choose the number of points being used. Pick one setting that sounds good to you, set it up and go out and shoot. Get comfortable, then move to some other topic and repeat. What I have tried to say is you need to get at least a basic understanding of the camera's options and pick them up one at a time. Good Luck.

mwsilvers Loc: Central New Jersey

A shutter speed of 1/350 second is pretty slow for sports unless you're talking about golf or shuffleboard. :) For freezing sports action the shutter speed should be at least 1/800 to 1/1000 second. An aperture of f/8 is also pretty small and with an appropriate shutter speed could never be really effective with inside sports event. If you have a good telephoto lens there is no reason not to shoot it wide open at f/4 or even f/2.8. Just stopping down to f/5.6 would allow you to double the shutter speed to a more usable 1/700.

BobR Loc: Norwalk CT USA

On the D7100 you can fine tune the AF of any lens. You can compensate for a lens that's back focusing for instance. The camera will remember the setting too of each lens.
Yes lately Ive gone to manual and auto ISO. Makes more sense to me than any other configuration. You already know the SS and aperture you want to begin with. The camera will get the exposure correct most of the time though you may need to compensate for the back ground. Bright sky needs +1 or so compensation for instance.

That said lenses like the Sigma and Tamron need good light for good shots. Bob

boberic Loc: Quiet Corner, Connecticut. Ex long Islander

All above suggestions are correct. My suggestion- Use BBF- half-shutter press is not the best for action. About focus points- I know that they have their purpose, and camera makers love to brag about how many their newest models have. I prefer center point focus as well as metering. Also, there is a place for manual, but sometimes shutter or apature priorty are better choices. My .02 cents.

Jacqui Burke Loc: Perkiomenville, PA

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I agree. I had the same problem with my D7200 and I sent it in for servicing. The mirror was out of position. I just got it back and haven't had a chance to try it out yet.



quote=davefales]Valid comments so far, but maybe your lens and camera do not match up well. A start for understanding:
https://luminous-landscape.com/are-your-pictures-out-of-focus/

"Causes of the problem

The main causes of the problem are camera and lens design, combined with manufacturing tolerances of mass produced devices.

Let’s face it, the vast majority of cameras and lenses are mass produced. If the manufacturing tolerances were incredibly tight, and each piece was tweaked and adjusted to perfection, prices would have to rise and quantities would shrink. Many people could not afford these very expensive cameras, and even those who could might have to wait for a long time to get their hands on one because of the limited supply. This would not be a particularly appealing situation.

Instead, things are massed produced to be “within tolerances”, but being within tolerances means that each piece is within a certain range of error that is considered to be “acceptable” by the manufacturer. Also, as most of us have experienced, periodically a piece that is out of spec seems to slip through all quality control and is sold to a customer.

The point I am trying to make is that the sensor will not be exactly where it is supposed to be, the mirror in an SLR will not come to rest in the perfect position, the autofocus system may be mounted just a wee bit off from the perfect position, it may be slightly out of perfect calibration, the focusing screen may be a little thinner or thicker than the spec, it may be placed slightly off in the camera, the lens mount may be slightly deeper or shallower than the spec, etc.

So, the consequence of mass production in large quantities at reasonable prices is that all these small deviations will pile up on top of each other and can cause the AF system in your camera to be out of focus. There is also a statistically significant probability that even if the autofocus system is working superbly, manual focus on the screen does not match the autofocus system on the camera."

You can make back/front focus corrections on your camera.[/quote]