15
\$\begingroup\$

The Nikon 1 cameras are famous for being able to track focus with their on sensor PDAF.

But the story goes that if light is low, it will switch to contrast-detect only and will not track focus as effectively.

Does anyone know at which point (in lux or EV levels) the Nikon 1 cameras switch focus mode and hence lose its high-quality track-focus capacities? (using either a kit lens or the Nikon 1 18.5mm f/1.8).

In other words, at which light level does focus-tracking work as advertised?

\$\endgroup\$
4
  • 3
    \$\begingroup\$ Your question is slightly misleading. Even in bright light the PDAF is only used to get the lens close to in-focus and then CDAF is used to do the fine adjustment. \$\endgroup\$
    – Michael C
    May 22, 2013 at 17:52
  • 1
    \$\begingroup\$ That is what Canon does but I have never heard of Nikon doing this. Do you have a source for this statement? Nikon's article says it switches between systems not that it uses both together. \$\endgroup\$
    – Itai
    May 23, 2013 at 15:13
  • 2
    \$\begingroup\$ I've e-mailed Nikon support with this question, they replied that they can not elaborate on it as it is classified information. So most probably you'll never find out... \$\endgroup\$ Mar 13, 2014 at 15:54
  • \$\begingroup\$ It's actually fairly easy to test observe. Contrast-detect necessarily involves hunting — the lens must move back and forth. Does that happen in good light, too? \$\endgroup\$
    – mattdm
    Jan 8, 2016 at 18:57

3 Answers 3

1
\$\begingroup\$

The Nikon V3 features sensitivity upto -3EV to + 3EV

Now -1 EV equals to 1.25 Lux and -0.5 EV equals to 1.75 LUX.....

So the Nikon V3 / 1 series camera PDAF AF system will work prefectly even in 1 or 2 Lux of light

"A camera with a 1-lux rating claims to be able to produce an image by the light of one candle that is about three feet away from the subject. Many cameras on the market today can do just that. The problem is that the resulting image may be of very poor quality."

\$\endgroup\$
3
  • 1
    \$\begingroup\$ Do you have a source for this information? \$\endgroup\$
    – Philip Kendall
    Sep 10, 2015 at 15:13
  • \$\begingroup\$ I am a camera freak and love to read camera related info always, I can't cite source but you can look for [link]en.wikipedia.org/wiki/Lux his symbol continues to be used in ISO standards, but the acronym EV is more ..... shutter time of 1 sec for ISO = 100) corresponds to a luminance of 0.01fc or 0.13lux. ... The formal relationship of EV to luminance or illuminance has limitations.midwesternmac.com/blogs/jeff-geerling/… \$\endgroup\$
    – Mike Menon
    Sep 18, 2015 at 17:56
  • \$\begingroup\$ More on converting EV to Lux at photo.stackexchange.com/questions/10093/… \$\endgroup\$
    – mattdm
    Jan 8, 2016 at 18:58
0
\$\begingroup\$

According to @Saaru Lindestøkke:

I've e-mailed Nikon support with this question, they replied that they can not elaborate on it as it is classified information. So most probably you'll never find out...

\$\endgroup\$
-1
\$\begingroup\$

It is not only the lux level, but also the aperture which determine the ability of a PDAF to work reliably. Even with the same amount of light arriving at the sensor, a higher aperture number (= a more closed aperture) can prevent the PDAF from working.

It appears that the "classic test" for AF systems is to photograph birds in flight. One review of a Nikon 1 series camera (probably an older model) noted that focusing of birds in flight becomes impossible when the lens has an aperture of 6.7 or more.

Obviously, the contrast ratio of the object you want to focus is also important. When I was doing "dog in flight" pictures, I have to take care not to photograph the dog from an angle where all the fur is black.

\$\endgroup\$
3
  • 3
    \$\begingroup\$ Generally, cameras will open the aperture of an autofocus lens to wide open during focusing and then close it to the desired f-stop during image capture. This mimics the behavior of earlier manual focus 'auto-aperture' lenses (which have an 'A' setting on the aperture ring) and the camera bodies upon which those lenses worked. \$\endgroup\$
    – user50888
    Feb 28, 2017 at 16:57
  • \$\begingroup\$ Can you provide any evidence that the Nikon 1 cameras focus stopped down, as opposed to wife open like the vast majority of cameras? \$\endgroup\$
    – Philip Kendall
    Feb 28, 2017 at 18:05
  • 1
    \$\begingroup\$ The Nikkor 70-200 f/4 VR with the TC-17E II teleconverter attached to the Nikon 1 will yield an aperture of 6.7 when wide open (assuming I got the math right). \$\endgroup\$
    – Klaws
    Mar 1, 2017 at 10:28

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.