Dynamic- AF area D700-- When, why ?

[andrew_fedon]

<p >So much to still get used to on the D700, differences from the older F4 film body. In the Dynamic – AF Area mode, after carefully reading the manual, I’m still somewhat hazy on the various options offered and the difference between them apart from the number of focus points. Can someone explain clearly:</p>

<p >When do I use and need 9 points ?</p>

<p >When do I use 21 points ?</p>

<p >When do I use 51 points ? and when do I use 51 points (3D tracking) ? In fact what is the difference between 51 points and 51 points (3D tracking) ?</p>

[hans_janssen]

<p>Read Thom Hogan's review of the D3, there is is better explained, but still not completely clear to me. The Af system is the same on the D700, so it not in that review.</p>

[ShunCheung]

<p>Please take a look at the section on auto focus in the D700 review here in photo.net: <a href="../equipment/nikon/D700/review/#auto-focus">http://www.photo.net/equipment/nikon/D700/review/#auto-focus</a></p>

<p>I typically use 21 points for shooting sports. I tend to get the best results that way. 9 points cover too small an area in the viewfinder/frame. It is very easy for a subject to move outside of the coverage among those 9 points and all of a sudden the camera will fous onto the background instead.<br /><br />To me, 51-point with 3D tracking is fairly useless. The Multi-CAM 3500 is supposed to coordinate with the color matrix metering system and is able to follow a subject if its color is different from the background. In reality, it loses track with the subject fairly quickly. I have that same bad experience with the D300, D3 and D700, all of them use that same AF module.</p>

[dan_brown4]

<p>If you shoot active subject matter, sports for example, experimentation will quickly reveal when dynamic AF yields great results. The better you are at tracking the subject, the fewer AF points you need. I agree with Shun, 51-point is a little nuts. Maybe for butterflies against a blue sky, or something like that.</p>

[rarmstrong]

<p>Andrew, I have the D300 with the same AF module and I agree that you have to experiment with what works best for you. The 51-point AF with 3D tracking works very well for flying birds against a bland sky. But, as soon as the bird flies below the tree line, I need to use the thumb switch and flick it over to a single point that I keep right on the bird. The multiple colors and textures of the background are confusing to the 51-point setting. I've used it for some football shots and when there are multiple players moving quickly in a jumble, I've found that a single point kept directly on the subject(like the ball carrier's face) gives me the highest number of in-focus shots. The system is fast, but like Shun says, it can't sort out everything.</p>

[elliot1]

<p>"When do I use and need 9 points ?" When 1 point doesn't do the job for you.</p>

<p>The better you are at tracking the subject, the less you can rely on the additional focus points (meaning if you can keep one point on the subject at all times, you really don't need additional points). Whether you should use 9 or 21 depends on what sport you are shooting and the surrounding. Try them out to see what works best for you subject matter and shooting style.</p>

[dave_bishop]

<p>I use 51 point 3D tracking on all my in flight raptor shots with open sky or treed backgrounds ( trees are slightly distant - 200 yards + , and out of focus ) and have a very high ( 85-90 % ) success rate. For me it's my best option.</p>

[ShunCheung]

<p>Generally speaking, the 9-point option is best if you have a very large subject that covers most of the AF point area so that it is unlikely that those 9 point will fall onto the background. Moreover, the fewer AF point you use, the less calculation the camera needs to make.</p>

<p>I have not used 51-point w/ 3D on any birds in flight shots. Perhaps I should give that a try. I have never been happy with 51 + 3D in the past.</p>

<p>Another thing to keep in mind is that the Multi-CAM 3500 actually works much better on the D300 since it covers almost 50% of the entire frame. IMO it is not as effective on FX.</p>

[peter_gilbert3]

<p>My take:<br>

Use 9-point when the subject is moving predictably in a single direction across the frame - example car racing or boats<br>

Use 21-point when the subject is moving unpredictably across the frame but mainly only on one axis (that is, moving either back or forward) - example football, tennis<br>

Use 51-point when the subject is moving unpredictably in all directions, left to right, up or down - example birds in flight.</p>

<p>Peter</p>

 

[andrew_fedon]

<p>Hmm, good answers, thanks all. Its clear that its not entirely a cut and dry crystal clear difference between them , but that a lot of experimentation is needed. For the same subject, different settings may work, and everyone has their own favourite, and I understand the notion that the fewer points to use the better. Can the designatable 'Fn' button be designated to toggle between the 9, 21, 51 points rather than having to go through the menu, which is rather more time consuming ?</p>

[peter_gilbert3]

<p>Looks like it can, with FN plus Dials, see Page 323 of the IM. I'v not tried this however so cannot verify.</p>

<p>Peter</p>

[thakurdalipsingh]

Response to Dynamic- AF area D700-- When, why ?

 

Andrew : Any success with all the answers you got for Dynamic- AF area D700? What is your experience in last year? have you tried on birds in flight? or what subject? Your experience can help me. I got D700 and D300S. Pl help<div></div>