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My take on CAM 2000

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Thanks. Rick and I work really hard to try to keep the podcasts interesting.

We've been snowed in the last two days here in Colorado, so our latest episode has been delayed.

The good news was that the time off allowed me to write the AF article! :)

-Jason

--
Jason P. Odell, Ph.D.
Author, 'The Photographer's Guide to Capture NX'
http://www.luminescentphoto.com/capturenx.html
Holiday discount for dpreview readers:
http://www.luminescentphoto.com/dpreview.html

Co-host, 'The Image Doctors' at Nikonians Podcasts
http://podcasts.nikonians.org
 
I've found that when using single-area dynamic AF, you really still need to keep the primary AF point on the subject. Where it works is if your subject moves off the primary AF point slightly. However, the gaps between the AF points (horizontal gaps) are big enough that with small objects you will lose focus lock. That's part of the reason I'm using Group Dynamic AF more.

-Jason

--
Jason P. Odell, Ph.D.
Author, 'The Photographer's Guide to Capture NX'
http://www.luminescentphoto.com/capturenx.html
Holiday discount for dpreview readers:
http://www.luminescentphoto.com/dpreview.html

Co-host, 'The Image Doctors' at Nikonians Podcasts
http://podcasts.nikonians.org
 
--
Nick
Herts, UK
 
I think the system in the D200 is very similar, however since I don't own a D200, I'll hold off on any direct comparisons.

What I do know is that the D200 only has a single cross-type sensor (the center one), so low-light focusing is probably not quite as good as that in the D2 series bodies.

I also don't know much about how the "wide area" focus mode works in the D200.

Conceptually, the other modes should behave similarly as those in the D2X.

-Jason

--
Jason P. Odell, Ph.D.
Author, 'The Photographer's Guide to Capture NX'
http://www.luminescentphoto.com/capturenx.html
Holiday discount for dpreview readers:
http://www.luminescentphoto.com/dpreview.html

Co-host, 'The Image Doctors' at Nikonians Podcasts
http://podcasts.nikonians.org
 
It will have to wait until I buy one. ;)

In the meantime, there is a very well put-together article on CAM 1000 over at Nikonians.

I would say the only exception I have with the recommendations in those articles is the part about using focus-priority (a1) for continuous servo mode. I'm guessing that that rationale would hold true with the D200 as well.

I think the bigger picture is that sometimes we lose sight of the limitations of the wonderful technology we currently have access to these days.

No AF system is perfect, but compared to what my old N70 used to do...

-Jason

--
Jason P. Odell, Ph.D.
Author, 'The Photographer's Guide to Capture NX'
http://www.luminescentphoto.com/capturenx.html
Holiday discount for dpreview readers:
http://www.luminescentphoto.com/dpreview.html

Co-host, 'The Image Doctors' at Nikonians Podcasts
http://podcasts.nikonians.org
 
An excellent article - highly recommended by me to anybody having D200 focus or soft lens issues.

I know some object to me pointing out in 6 months I have seen no "soft" threads using AF targets within the cameras AF capabilities and 111 using AF targets likely to be outside the AF capabilities. Your article confirms what many of us know - for some types of target well identified in your article AF has a hard time acquiring good focus.
--
Leonard Shepherd

Usually skill in using equipment has more to do with good photography than the equipment itself.
 
Jason Odell said:
I've found that when using single-area dynamic AF, you really still
need to keep the primary AF point on the subject. Where it works
is if your subject moves off the primary AF point slightly.
However, the gaps between the AF points (horizontal gaps) are big
enough that with small objects you will lose focus lock. That's
part of the reason I'm using Group Dynamic AF more.
Click to expand...
I don't understand why neither the camera nor EXIF appears to
give any indication of which sensor ended up being used when
and if the camera decided to switch its attention from an initially
selected sensor to a more interesting one.

Perhaps I misunderstand how selection works in continous autofocus
versus single-servo autofocus mode. With Group Dynamic, you will
receive a confirming flash on the selected sensor with AF-C but not
AF-S. But as I understand, even with AF-S, it might switch. Is this
wrong? Does the focus lock on AF-S preclude switching and this
therefore explain why AF-C never tells you which sensor is currently
being used?

The problem of real-world objects being hard to see by design
compared with their backgrounds would be helped if the camera
would help remind us what it's doing. Unlike rugby jerseys intended
to be made out from a distance, a sparrow, fawn, or puppy against a
natural background is often less attractive to the contrast-detection
algorithm in your firmware (or your wetware) than that background.
Anything that ever uses more than one sensor risks losing track of
what nature's design itself seeks to hide. I wish the camera would
tell me what it was doing here so I could make better judgments.

Probably I'm just not understanding something, though. If so, I'd be
happy to learn how to handle this better so I know what it's doing.

--tom
 
--
http://www.maginimagen.com

---------------------------------------------------------------------------------
Equipment listed at profile
 
when you get a D2 and just stick the camera on single servo and then choose AF-S or AF-C. I like AF for its speed, and multiple focus spots for framing convenience, but I cannot give up control over what the camera focuses on.
 
This depends on the type of photo you are doing. For really fast actions, if you can keep your subject in the viewfinder you can be happy. Then the camera and your luck must do the rest. On the other hand, for macro, even AF-S isn't good enough, I get better results with manual focusing.
--
http://www.frikosal.blogspot.com
 
Jason:

Thanks for a great article. Making advanced technology understandable is quite a challenge and you seem to have met the challenge here.

Part of the problem with understanding the Nikon AF systems, in my opinion, is that Nikon's AF naming conventions are confusing. The word "dynamic" sounds cool, but it adds nothing to the understanding. The word "area" is ambiguously used to refer to a single sensor.

I like to think of the AF areas in relation to the sensors that are active. Thus:

1. Single sensor AF (Nikon calls it "Single Area AF")
2. Group sensors AF (Nikon calls this "Group Dynamic AF")
3. Full frame sensors AF (Nikon calls this "Dynamic Area AF")

Number 2, of course, gets subcategorized into 2A: Group sensors AF with center sensor priority and 2B: Group sensors AF with closest subject priority.

Number 3 gets subcategorized into 3A: Full frame sensors AF with selected sensor priority, and 3B: Full frame sensors with closest subject priority.

The words are strictly utilitarian, but at least to my simplistic way of thinking, they make things more comprehensible.

Another poster asked a question that I hope you will comment on. What happens to the AF sensors when the Focus Selector Lock is engaged? Does this override the "dynamic" AF? I have this engaged frequently because the Multi-selector button is so dang sensitive that the active sensor jumps around if I just breath on the button.

Thanks, Jason.
 
I have become a Jason Fan after I bought his NX book. Now this..

Can't wait to get the D200 version ;)

Thanks Jason.
 
Jason Odell said:
I would say the only exception I have with the recommendations in
those articles is the part about using focus-priority (a1) for
continuous servo mode. I'm guessing that that rationale would hold
true with the D200 as well.
Click to expand...
You're right that setting focus-priority for continuous servo doesn't
work out at all with divorcing focusing from the shutter release by
relegating it to the AF-ON alone. I only leave configure it for focus
priority when I'm handing the camera to someone else; it's remarkable
how the simple matter of first half-pressing the shutter for AF/AE lock
on your desired target subject is incomprehensible to 98% of people
you hand the camera to, and how untrainable they are in this, considering
how even a point-and-wait digicam much prefers you to do this.

Let me amend my first statement: you could use focus priority on a
recomposed AF-C shot to effect a trap-focus mechanism under a
divorced AF-ON, just as you can with AF-S. I think.

--tom
 
In the context of this discussion of a a"user guide", it is important to understand that Nikon thought through the AF-ON/AF-C Focus Priority problem very carefully and specifically engineered the physical configuration AE-L/AF-L button as a solution.

--
Regards,
Neil
 
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