Reader Questions: Autofocus Modes, Tripods and Teleconverters
Reader Saurabh Singh wrote in from India to ask a few questions, which I’ll answer here in case they might help others as well.
1. Autofocus — Single point or 51 point & 3d tracking, which tracks the best? And which do you use?
For motorcycle racing, I have found that the less you ask your gear to do and the more of the work you do yourself, the better your results will be. This question is a good example. I have never had good results with the 3D tracking system, I suspect because MotoGP bikes simply move too fast. This system might be fine for a soccer game where the subject is a running human being, or something similar. But MotoGP requires that I do as much of the heavy lifting as possible.
Therefore when it comes to autofocus modes I use Single Point focus. This requires that I track the moving subject accurately while moving the camera and lens. This takes practice.
For a while I used the 9-point Dynamic area focus. This is a good option for those new to motorbike racing. It gives you some room for error as you have a larger viewfinder area in which to place your moving subject.
But once my tracking skills improved, I switched to Single Point and my results improved along with that switch, I believe because that simplified what I was asking of the autofocus system.
2. While panning, which settings do you recommend? I’m using a tripod at present, and I am trying to pan with VR on and set to normal mode with Shutter Priority mode with shutter speeds between 1/160 to 1/250. Going below that my images are totally blurry or unusable, taking into consideration your tip that the front of bike or rider’s helmet has to be in focus.
Panning settings determine how much motion blur you get and thus what your image will look like. A given shutter speed range will not fit a broad variety of situations, because the speed of your target relates directly to what shutter speeds will give you desirable results.
For example, if you are working in a slow corner, such as with the image above of Tom Sykes, in order to maintain some motion blur and show movement in the image, you’d need to use a slower shutter speed than if you are panning while your subject is going 100MPH.
Notice the front wheel of Sykes’ Kawasaki. It shows little or no movement, which is not what I was after. I had too high a shutter speed for this slow corner at Miller Motors Sports Park. Probably I had forgotten to check this setting while moving here from a faster section of track. A shutter speed that was appropriate before was now too fast and I didn’t notice when I made this exposure.
Given that how much motion blur is ‘just right’ is a subjective issue, I’d say your range of 1/160 to 1/250 is fine if the bikes are moving nicely. If they are slowed way down for a tight corner, this range might be a bit on the fast side. (Again, this depends on how much blur you want.) However, the slower your subject is going, the easier it is to get a sharp image of it, at least in theory. Again, practice will help.
As for shooting from a tripod, I don’t know if this is helping you or hurting you. I don’t know anyone in MotoGP who uses a tripod. We all use either a monopod or muscle and bone to support the longer lenses. Among the monopod users, some rest the thing on the ground, others use a belt support of some kind, as I do. I prefer the belt because it allows me to move the camera more easily than if the monopod is anchored on the ground. There is something about the shorter distance between the camera and its pivot point that I find easier. But there are many shooters who get good results having it on the ground.
Because bikes rarely pass by you on a perfectly flat plane, i.e. one that is aligned with the rotation of your ball head when mounted on a tripod, I expect a tripod is not ideal. With a monopod as a support, you can move not only side to side but also up and down. In my experience, this is a big advantage. But if you are getting good results with a tripod, more power to you!
You are also using VR (Vibration Reduction). I do not use VR on the 500 at trackside, and I don’t know any of my colleagues who do either. As I stated above, the less you ask your gear to do, the better it will do the really important things. Asking the autofocus system to track a MotoGP bike AND apply VR to each exposure is asking a lot. I get better results replying on technique rather than VR.
The one exception to my No-VR rule is if I’m shooting into a dark garage and have to use a really slow shutter speed. Then I might switch VR on. But at trackside, never.
So I suggest you experiment with various shutter speeds at different sections of a given track to see which speeds give you the amount of blur you’re after. Then practice until you can get sharp images with a lot of blur. As I said before, this takes practice.
3. Do you recommended using Nikon 1.4x II Teleconverter with 200-400vr on D4 for better reach without compromising quality?
I have only owned one teleconverter, a 1.7 several years ago. I used it with the first version of the 200-400mm and with the 70-200mm f/2.8. I did not get good results from either combination, so I sold the 1.7. Recently I tried a 1.4 II and was very pleased with the results when joined to my 500mm f/4, and I intend to get one this season.
That said, I haven’t tried the 1.4 with the 200-400mm and I have no idea if they would work together, sorry. If you have the opportunity to rent a 1.4 and try it, that’s what I would do.
One note on Auto Focus
I suggest you check your Focus Lock to see if it’s on its default setting, which will be too long for motorcycle racing. Experiment with whatever shorter options your camera offers. If the Focus Lock is too long, the subject may have moved out of focus before the auto focus system adjusts, resulting in more blurry images.
I hope this info helps, and thanks for the questions, Saurabh.