Fuji XT-2 Low light AF

eagle

New Member
Any word on the "campfire light" AF performance with the XT-2? My Xpro2 is horrendous around the campfire. No matter which way the 'settings" are configured... It hunts forever, moment is long gone... Hopefully the new firmware will fix this, doubtful. It does good in most light, but man, when it gets dim, forget it, give me a DSLR any day of the week for that type of work....
 
Even my old X-Pro1 worked at campfires, so I can't see problems with the X-Pro2 or X-T2 there. Of course, CDAF use involves some hunting, so using a bright lens is the key when the light is low. It reduces CDAF hunting or even allows the PDAF to kick-in.

My X-Pro2 is already capable of surpassing DSLR PDAF in low light, which is not surprising given that DSLR AF sensors are calibrated to f/2.8 no matter what, while MILCs like the X-Pro2 can actually make use of f/1.4 or even f/1.2. That's at least 2 stops brighter and can compensate any disadvantage that may still exist with on-sensor PDAF technology vs. dedicated AF sensors.

With the upcoming firmware, PDAF use will increase by 100%, which should make it even easier to focus faster more often. Just make sure to select appropriate focus frame sizes or focus zones and to target parts of the subject that are suitable for non-cross sensor PDAF recognition. As you may be aware of, my book in the X-Pro2 contains several tips regarding the proper us of AF frames and focusing in low light.
 
Found these campfire shots taken with an X-Pro1 and firmware 1.xx in 2012:

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Btw, I have just measured that my X-T2 (using beta firmware 1.42) at f/1.8 (Zeiss Touit 32mm) can use PDAF down to -3 EV (when the subject is right). This would mean that I could use it down to -4 EV with my 56mmF1.2 lenses. I'll have to try this later.
 
Now, the one with the young boy. Focusing on the face with just dim, slightly distant, firelight is what I'm having trouble with. In a scenario with similar light, again on subject, is the most tough, never mind AF tracking. My D810 just focuses on the eye, locks, and then tracks the subject as they, or I, swayed and moved about, all in AF-C "Auto" mode... maybe face detect would fare better in those instances...
 
As you know from my book, you can't really use AF-C in dim light unless you shoot wide open with a bright lens, so AF-S it is.

I also wouldn't use face detection. It's not always reliable. Personally, I rarely use anything that I cannot fully control myself. I'm usually better off trusting my own skills, so I use AE modes or AF tracking (especially 3D tracking, which is usually limited to CDAF) only when I'm not fast enough to master the given task.
 
Ah, well, if the 23 1.4 and 56 1.2 ain't fast enough then I'm gonna have to stick with Nikon, thanks anyway... Pricey test..
 
My D810 just focuses on the eye

My X-Pro2 focuses on things that are pretty much black and unrecognizable when seen with my own eyes, so as long as one can still make out anything in the OVF of a DSLR (or in the OVF of the Pro2), my X-Pro2 will always focus on it as long as there's any contrast.

Basically, the X-Pro2 works like a night vision device, showing me things in the EVF that are otherwise completely dark, and focussing on them in a reliable and reasonably fast way. Bright lenses are the key, of course. With the new firmware, things will further improve in the ways already mentioned above, and in my First Look Review, and in this recent article by Fujifilm.
 
Ah, well, if the 23 1.4 and 56 1.2 ain't fast enough then I'm gonna have to stick with Nikon, thanks anyway... Pricey test..

Yes, those are more than fast enough from a brightness viewpoint. As long as the camera settings allow wide-open AF, it really isn't much of an issue. After all, campfire light isn't that dark. There are much more demanding situations, and -3 EV (where I could even use PDAF with a f/1.8 lens in my X-T2) is considered a nightly landscape that is lit by less than a full moon.
 
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sounds like mine is defective...

It's certainly possible, but it's impossible to tell from here. It can also be number of other factors. The most common from my workshop experience are setting the wrong AF mode, picking AF frames that are too small, and/or picking targets that have little or no contrast. My quick suggestion for low light: set AF-S and either Single-Point with a larger focus frame or Zone with a small 3x3 grid, and use the "autofocus trick" (aka shutter mash) that's described in my book and in various forums.
 
I'm on it, thanks again for your time...

No worries. I hope everything turns out as it should. The October firmware update will certainly improve things, again, but that doesn't mean that the current camera shouldn't focus under such conditions (I reckon campfires require about 3 EV exposure, which should well in the range of the AF system).
 
Gents, thank you for an interesting and informative exchange. I realise I've yet to give my X-Pro2 a good low-light workout but I'd basically do everything that Rico suggests to get the best out of it.
 
Gents, thank you for an interesting and informative exchange. I realise I've yet to give my X-Pro2 a good low-light workout but I'd basically do everything that Rico suggests to get the best out of it.

You can also try to use the AF Illuminator to focus under such tricky conditions, but I usually turn it off because it's often shaded by larger lenses and lens hoods that I normally don't want to take off.

That said, I have just received a package with a prototype EF-X500 flash, and this unit can be very useful to provide AF illumination with its built-in LED secondary flash.
 
Very informative post.

For what it's worth, My Pro2 was able to lock focus on the girl in this photo in lighting far worse than campfire light. Using a 2.8 lens. This was in a VIP party, very very dim and backlit. Not a great photo, but I kept it just for the fact the Pro2 locked focus in difficult conditions.
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Join to see EXIF info for this image (if available)
 
X-T1 and 56 at 1.2... Didn't have any issue focusing. I had the focus box one size up from the minimum, AF-S of course, and usually I aim for the edge of a face to grab the contrast, then hold half press and reframe a tiny bit.

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KBRX5621
by gordopuggy, on Flickr

In some situations, like where the fire dies down and it truly is DARK, I usually find it faster to manually focus, period. Flip the front dial to MF, which enables the handy center 100% crop box in the EVF. Night Vision engages (I like that analogy, Rico), I can see well enough to judge focus, and as long as neither of us is moving around much it comes out right. If you two ARE moving around a lot... in pitch dark ... I'm not sure you can really complain tooooo much.
 
Sadly for me it was the low light focusing that made me sell my Fuji gear and now I'm camera less I took it back to the shop to ask advice on settings etc but no better it's a shame as I liked the system. I'll wait for a year or two and see what happens as not interested in other systems.
 
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