Nikon D7200 for Wildlife

bbg404

bbg404

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Ben
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Evening all ..... My main focus is Landscapes but I'm sticking my toes in to wildlife

I already owned the Nikon 80-400 AF-S and loved it so thought I'd buy a D7200 as my wildlife body I've had some good results from my shoots with Red Squirrels and Red kits but today I went to the Farnes and struggled with focusing

So has anyone had the D7200 and 80-400 and noticed it slow to refocus if you loose focus???? And was it the lens or body at fault??

So for example your tracking a bird flying straight at you or even across in front of you the bird changes direction and you lose it in the view finder for a split second did you notice a delay before it started looking to focus again?
 
bbg404 said:
Evening all ..... My main focus is Landscapes but I'm sticking my toes in to wildlife

I already owned the Nikon 80-400 AF-S and loved it so thought I'd buy a D7200 as my wildlife body I've had some good results from my shoots with Red Squirrels and Red kits but today I went to the Farnes and struggled with focusing

So has anyone had the D7200 and 80-400 and noticed it slow to refocus if you loose focus???? And was it the lens or body at fault??

So for example your tracking a bird flying straight at you or even across in front of you the bird changes direction and you lose it in the view finder for a split second did you notice a delay before it started looking to focus again?
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Yep! Going through it now, same problem that you have, I'm using the sigma 150_600c with the D7200 lost tracking a few times over water, tracking birds. I'm using spot metering
 
Thank god it's not just me!

I've searched Google and can't seem to find anything I've asked on other pages and I've tried everything in regards to testing all the AF settings

Have you tried a different body / lens combo to figure out is it the body or lens?

I believe the Sigma 150-600 has slightly slower AF than the Nikon 80-400 anyway but I don't feel I have slow AF I feel the delay is more of an issue
 
Losing focus is not unusual with fast moving subjects especially ones coming straight at you with backgrounds, tracking them can be difficult. The slow to refocus part is most likely the lens as its a f4-f5.6 variable aperture, if it was a 70-200 f2.8 or 300 f2.8 the focus speed would be faster and able to keep up better.

What is the the lens focus limiter set to? Do you keep it to full range or switch to the reduced range? Having it set to reduced range does mean it has less range to travel over so makes it faster.

There are several menu options regarding focus, have you checked what their settings are? I'm guessing you were using AF-C with single or small group focus point. Does it happen on your other camera body as you say the D7200 is your wildlife camera?
 
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Much as I love my 80/400 lens and find it very good and sharp for most things, birds in flight are not the best, get far better results with the 70/200 2.8 on both
a D7100 and D7200
AF on the 70/200 seems fractionally faster
 
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As above, small-ish aperture tele zooms are not the fastest to focus and it will take time to lock on to small fast moving subjects. That being said with practice you can do it but just be prepared for a lot of frustration and focus hunting. As also mentioned above something like a 70-200mm f2.8 will focus much faster, the difference between my 150-600mm f5-6.3 and my 70-200mm f2.8 is night and day.
 
Been on the Farnes this week with my D7200 & D810 paired with my 300 f4 PF & 24-120.
The small and fast flying Puffins are challenging, all the more so with a tricky background, my keeper rate on the 1st visit was lower than last year when I took my 500 f4 & 70-200 but couldn't be carrying the 500, tripod & gimbal this year. Will be making at least one more visit and will be slowing down to capture specific shots.
A great place to visit and pics to post soon :)
 
bbg404 said:
Thank god it's not just me!

I've searched Google and can't seem to find anything I've asked on other pages and I've tried everything in regards to testing all the AF settings

Have you tried a different body / lens combo to figure out is it the body or lens?

I believe the Sigma 150-600 has slightly slower AF than the Nikon 80-400 anyway but I don't feel I have slow AF I feel the delay is more of an issue
Click to expand...
I suspect it will be the same as the d7100 I use all focus points or 3d and back button focus, you should have better luck
 
I recently did some BIF shots at a bird show, granted they were larger birds and moving less erratically and probably closer than your subjects but using a d7200 and sigma 50-100 f1.8 I found that the AF didn't hunt, tracking worked great and the AF speed was pretty much instant. I used either 9 or 21 point mainly.

It could well be your lens choice that's the problem.
 
Agree with Adam I don't have problems with the Nikon 300mm f4, well when I do its me not the lens
 
It's not the aperture per se, but it is the lens... The 80-400 AF-S is known for not being a particularly fast lens to AF, but better than the previous version. The biggest issue with AF is always the light/contrast of the scene/subject, and how well the lens transmits that at max aperture.

FWIW, the PDAF module has it's own lenses/openings and they have an effective aperture of around f/5.6 (or slightly less)... AFAIK, none receive *more light* at apertures wider than that.
 
sk66 said:
It's not the aperture per se, but it is the lens... The 80-400 AF-S is known for not being a particularly fast lens to AF, but better than the previous version. The biggest issue with AF is always the light/contrast of the scene/subject, and how well the lens transmits that at max aperture.

FWIW, the PDAF module has it's own lenses/openings and they have an effective aperture of around f/5.6 (or slightly less)... AFAIK, none receive *more light* at apertures wider than that.
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But isn't it a cumulative effect, and so faster lenses letting more light in are going to help the AF system? Otherwise it wouldn't make any difference whether you used an f1.8 or f5.6 lens when focussing in low light, yet from experience I think most of us find that it does.
 
snerkler said:
But isn't it a cumulative effect, and so faster lenses letting more light in are going to help the AF system? Otherwise it wouldn't make any difference whether you used an f1.8 or f5.6 lens when focussing in low light, yet from experience I think most of us find that it does.
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That really depends on the system design overall... Many newer cameras have f/2.8 AF sensors. The related f-stop has to do with their location on the AF module, and not the light as such. But that does provide additional AF points for accuracy/speed.

But yes, it's cumulative... A very sharp lens is sharper w/ greater contrast at a wider aperture, which is better for the AF sensor. And some sensors have additional AF points located to make use of wider apertures (up to f/2.8). And some AF sensors are more sensitive to lower light levels (the EV rating). But none of them actually get "more light" at apertures wider than ~ f/5.6, so that's not really part of the issue.

I.e. if the lens isn't particularly sharp/sharp wide open with good contrast (a high MTF), and the AF module doesn't have *f/2.8 focus points, then the max lens aperture **won't make a difference.

*most AF points are located for f/5.6, and some cameras only have "f/5.6 points"
**unless it's smaller than the minimum available focus points... i.e. f/8 w/ TC's on many cameras (causes vignetting on the AF module).
 
sk66 said:
That really depends on the system design overall... Many newer cameras have f/2.8 AF sensors. The related f-stop has to do with their location on the AF module, and not the light as such. But that does provide additional AF points for accuracy/speed.

But yes, it's cumulative... A very sharp lens is sharper w/ greater contrast at a wider aperture, which is better for the AF sensor. And some sensors have additional AF points located to make use of wider apertures (up to f/2.8). And some AF sensors are more sensitive to lower light levels (the EV rating). But none of them actually get "more light" at apertures wider than ~ f/5.6, so that's not really part of the issue.

I.e. if the lens isn't particularly sharp/sharp wide open with good contrast (a high MTF), and the AF module doesn't have *f/2.8 focus points, then the max lens aperture **won't make a difference.

*most AF points are located for f/5.6, and some cameras only have "f/5.6 points"
**unless it's smaller than the minimum available focus points... i.e. f/8 w/ TC's on many cameras (causes vignetting on the AF module).
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Interesting, thanks. The whole f number of the focus point thing can be quite confusing tbh as when I had the Sony A77-II sony made a big song and dance about it having a highly sensitive f2.8 centre AF sensor, but yet if you read other literature that suggests that f2.8 sensors can only be used with lenses that are f2.8 and faster. So then what's the benefit of an f2.8 sensor? I know with my Nikon D750 they mention about having f8 sensors which are better as they allow the use of slower lenses with TC's. I understand the latter, but I don't understand the benefit of an f2.8 sensor?
 
snerkler said:
but yet if you read other literature that suggests that f2.8 sensors can only be used with lenses that are f2.8 and faster. So then what's the benefit of an f2.8 sensor?
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It is kind of confusing and hard to understand... If you think of every part of a lens as being a smaller lens, it helps to understand that every part of a lens sees/projects a complete image. And aperture controls "the size" of the lens area from which they all overlap, which is why some wide apertures can cause vignetting (you start to see the edges of the lens element). And it is for this same reason that different apertures require different AF point spacing.

Here is a pic of the PDAF sensor of the Canon 1DX. Each section (L/R/C) has it's own lens over it. There is also a "mask" for each group which controls the size/area (to minimize flare/contamination).
1dx-sensor.jpg

The 1Dx has all cross type sensors which for the f/5.6 points means it has both horizontal and vertical sensors for a single AF point.
Because F/2.8 is larger, the AF points for that aperture have to be placed farther out from center. And in order to do that and also make them "cross type" they placed them on a diagonal, sensing both vertical and horizontal lines (but less accurately).
The 1Dx does not have f/8 AF which means beyond f/5.6 the area covered starts to become smaller than the sensor spacing, simulated by the yellow circles.

The benefit of f/2.8 points is not gathering "more light", but it is more AF sensors taking advantage of another (wider) portion of the lens elements for increased accuracy. The technical references I have seen show that the light reaching the AF sensors is equivalent to f/7.5... but that has to be specific to a particular PDAF module design and the lenses/masks it uses.

1Dx AF module field lenses
TS560x560~3011746.jpg

1Dx sensor masks underlying the lenses and overlaying the sensor chip (simulated/educated guess, not quite to scale/correct placement).
TS940x940~3011806.jpg
 
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sk66 said:
It is kind of confusing and hard to understand... If you think of every part of a lens as being a smaller lens, it helps to understand that every part of a lens sees/projects a complete image. And aperture controls "the size" of the lens area from which they all overlap, which is why some wide apertures can cause vignetting (you start to see the edges of the lens element). And it is for this same reason that different apertures require different AF point spacing.

Here is a pic of the PDAF sensor of the Canon 1DX. Each section (L/R/C) has it's own lens over it. There is also a "mask" for each group which controls the size/area (to minimize flare/contamination).
View attachment 67583

The 1Dx has all cross type sensors which for the f/5.6 points means it has both horizontal and vertical sensors for a single AF point.
Because F/2.8 is larger, the AF points for that aperture have to be placed farther out from center. And in order to do that and also make them "cross type" they placed them on a diagonal, sensing both vertical and horizontal lines (but less accurately).
The 1Dx does not have f/8 AF which means beyond f/5.6 the area covered starts to become smaller than the sensor spacing, simulated by the yellow circles.

The benefit of f/2.8 points is not gathering "more light", but it is more AF sensors taking advantage of another (wider) portion of the lens elements for increased accuracy. The technical references I have seen show that the light reaching the AF sensors is equivalent to f/7.5... but that has to be specific to a particular PDAF module design and the lenses/masks it uses.

1Dx AF module lenses
View attachment 67584

1Dx sensor masks underlying the lenses and overlaying the sensor chip (simulated/educated guess, not quite to scale/correct placement).
View attachment 67586
Click to expand...
Thanks, really useful that. Just to clarify, are you saying that f2.8 sensors are more accurate than f5.6, but the disadvantage is that you can't use slower lenses with them? Also, in the example with the 1dx above, are you saying that the sensors in the outer image circle created by the f2.8 lens are less accurate, and so for a 1Dx (and other similar cameras) AF is going to be more accurate with f5.6 lenses than f2.8 (and wider)?
 
F/2.8 sensors *should be* more accurate than f/5.6 sensors because it adds additional "sample points" of the same image portion... the f/2.8 sensors are not "stand alone," they add to the f/5.6 sensor information. The diagonal sensors cannot be as accurate in sensing a horizontal or vertical line as a horizontal/vertical sensor would be (to a contrast line at 90*)... but conversely they will be more accurate in sensing a diagonal contrast line at 90* to them. But again, they are not stand alone... they provide "more of the same" combining w/ the f/5.6 (center) sensors.

This is where it gets (more) confusing... and perhaps my earlier images didn't help. It takes two sets of lines in the same orientation to discern one difference in phase. i.e. in the groups the two sets of horizontal lines compare against each other, and the two sets of vertical lines compare against each other (and so on). Each set of lines that compare will each have their own lens w/ mask (I didn't provide that image). The field lenses divide the image circle into the (typically) three zones, and then the group lenses focus portions of those zones. But the group lenses all see the same thing (detail).

The D300 has the same 3 field lenses. Under those are the group lenses w/masks. This image shows a D300's sensor lines, point mapping, and image projection... it is an "f/5.6 sensor." As you can see, the lines/groups are not "separate".... they combine/compare information.
TS560x560~3012476.jpg

Most of this information I learned from Marianne Oelund who posts some very technical/interesting stuff on DPR.
This article goes into the D300 AF Module in great detail and it is where the above image came from.
 
sk66 said:
F/2.8 sensors *should be* more accurate than f/5.6 sensors because it adds additional "sample points" of the same image portion... the f/2.8 sensors are not "stand alone," they add to the f/5.6 sensor information. The diagonal sensors cannot be as accurate in sensing a horizontal or vertical line as a horizontal/vertical sensor would be (to a contrast line at 90*)... but conversely they will be more accurate in sensing a diagonal contrast line at 90* to them. But again, they are not stand alone... they provide "more of the same" combining w/ the f/5.6 (center) sensors.

This is where it gets (more) confusing... and perhaps my earlier images didn't help. It takes two sets of lines in the same orientation to discern one difference in phase. i.e. in the groups the two sets of horizontal lines compare against each other, and the two sets of vertical lines compare against each other (and so on). Each set of lines that compare will each have their own lens w/ mask (I didn't provide that image). The field lenses divide the image circle into the (typically) three zones, and then the group lenses focus portions of those zones. But the group lenses all see the same thing (detail).

The D300 has the same 3 field lenses. Under those are the group lenses w/masks. This image shows a D300's sensor lines, point mapping, and image projection... it is an "f/5.6 sensor." As you can see, the lines/groups are not "separate".... they combine/compare information.
View attachment 67594

Most of this information I learned from Marianne Oelund who posts some very technical/interesting stuff on DPR.
This article goes into the D300 AF Module in great detail and it is where the above image came from.
Click to expand...
Cool thanks for this comprehensive post, very interesting.
 
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