Focusing in low light - Solution to a non-issue

Started May 30, 2011 | Discussions
bdcolen
Junior MemberPosts: 31
Like?
Focusing in low light - Solution to a non-issue
May 30, 2011

Everywhere I look, I see comments about problems focusing the Fuji X100 in low light. Even Dpreview, which is usually spot on in its criticisms and observations, complained about this problem.

Well...When I first received my X100 I, too, noticed that it just did not want to focus in low light. But I discovered that if the ISO is set sufficiently high to capture images at a reasonably shutter speed in a given level of ambient light, the problem disappears. Try it. I found that at 6400 ISO, 3200 ISO, and even 1600 ISO, I was able to focus without any problem in a conference room in which the only light came from a slide show projected on a screen, and the screen of the laptop running the slide show - which is to say, it was a dark room with only some extraneous light.

Does the X100 have some incredibly annoying firmware bugs? Absolutely. Are there some focusing issues? Absolutely. Lousy battery life? Yup. Does it freeze up on occasion? It sure does. Does it need a firmware upgrade? Desperately. But is low-light focusing one of its issues? No.

And by the way, neither are allot of the other 'problems' people have been complaining about. Menu problems? Just learn the menus, as you would with any other camera. Problems with the center wheel and button? I have big fingers and I don't have any problems - other than the fact that choices for things such as the macro feature are on the screen too briefly. But that's not a button problem, it's a firmware problem.

As Dpreview and other reviewers have noted, the images are fantastic - as are the bright optical viewfinder, the build, the feel, the lens quality, and the ability to work silently.

jack_h
New MemberPosts: 12
Like?
Re: Focusing in low light - Solution to a non-issue
In reply to bdcolen, May 30, 2011

Well...When I first received my X100 I, too, noticed that it just did not want to focus in low light. But I discovered that if the ISO is set sufficiently high to capture images at a reasonably shutter speed in a given level of ambient light, the problem disappears. Try it. I found that at 6400 ISO, 3200 ISO, and even 1600 ISO, I was able to focus without any problem in a conference room in which the only light came from a slide show projected on a screen, and the screen of the laptop running the slide show - which is to say, it was a dark room with only some extraneous light.

Hi, one question. Did you set ISO manually and disable the Auto ISO in the menu?

Reply   Reply with quote   Complain
lighttoart
Junior MemberPosts: 47
Like?
Re: Focusing in low light - Solution to a non-issue
In reply to bdcolen, May 30, 2011

Good tip for low light focusing. What I have found for setting macro is quickly double click the macro button and your set to go. You don't even need to be looking at the screen.

My experience with the x100 has been excellent. I believe it is set up well and one needs to learn the ins and outs; such as the two points mentioned. I have been saving tips as they are mentioned in this forum and that has been very helpful. I personally want to say "Thanks, Fuji" for creating a fun, thinking photographer's camera...not bad looking either!

It would be interesting to run a thread on how everyone is setting up their camera. I'm guessing it varies by shooting style and that many owners may not have it set up for the way they shoot. As mentioned many times, this is not a point and shoot.

The only glitch I've experienced so far is the occasional freezing. I haven't been able to determine if I'm doing something at that moment to cause the freezing (such as trying to access "play" or changing settings while the camera is still busy recording a shot). These are large files, especially if shooting Raw and jpeg together.
Thanks, Forum. Keep the tips coming.

Reply   Reply with quote   Complain
johnkkraus
Junior MemberPosts: 43
Like?
Re: Focusing in low light - Solution to a non-issue
In reply to jack_h, May 30, 2011

I've had occasional freezing issues on playback. Suddenly the forward or back button does nothing. Then they begin to work again.
--
John Kraus

Reply   Reply with quote   Complain
Paulo Abreu
Veteran MemberPosts: 7,105Gear list
Like?
Re: Focusing in low light - Solution to a non-issue
In reply to bdcolen, May 30, 2011

Hi,

bdcolen wrote:

Well...When I first received my X100 I, too, noticed that it just did not want to focus in low light. But I discovered that if the ISO is set sufficiently high to capture images at a reasonably shutter speed in a given level of ambient light, the problem disappears. Try it. I found that at 6400 ISO, 3200 ISO, and even 1600 ISO, I was able to focus without any problem in a conference room in which the only light came from a slide show projected on a screen, and the screen of the laptop running the slide show - which is to say, it was a dark room with only some extraneous light.

Am I understanding this correctly? Are you just figuring that if you choose a very high ISO, for the same "reasonably" shutter speed, you get a much smaller aperture which leads to an increased DOF that "masks" the focus error?

This is not a correction for any (if existent) focus error - this is a basic principle.

But excuse me if I am understanding everything wrong.

Regards

-- hide signature --

Paulo Abreu,

'It is not worthy to make a video of your life - just keep the best moments in
pictures!'

 Paulo Abreu's gear list:Paulo Abreu's gear list
Fujifilm FinePix X100
Reply   Reply with quote   Complain
Andy Westlake
dpreview AdminPosts: 2,915Gear list
Like?
Focusing in low light - non-solution to a real issue
In reply to bdcolen, May 30, 2011

bdcolen wrote:

Everywhere I look, I see comments about problems focusing the Fuji X100 in low light. Even Dpreview, which is usually spot on in its criticisms and observations, complained about this problem.

Well...When I first received my X100 I, too, noticed that it just did not want to focus in low light. But I discovered that if the ISO is set sufficiently high to capture images at a reasonably shutter speed in a given level of ambient light, the problem disappears. Try it.

Weirdly, that actually describes how I had the X100 set up when I was using it in low light - with manually-set high ISOs. Because, well, the light was low, so I needed them (and I suspect the same is true of anyone else who's commented on this). And despite this I found that the X100 genuinely struggled at low light levels where cameras like the GF1 or E-PL2 (with 20/1.7) still focus perfectly happily. The X100 tends to need a high contrast target to lock onto; otherwise it gives up and defaults to a focus distance of about 3m (so if your subject happens to be at 3m, you're just fine).

I'd also point out that there's no obvious technical reason why changing the ISO should help the AF.
--
Andy Westlake
dpreview.com

 Andy Westlake's gear list:Andy Westlake's gear list
Fujifilm FinePix F30 Zoom Olympus Stylus Verve S Olympus XZ-2 iHS Canon EOS 5D Panasonic Lumix DMC-GF1 +11 more
Reply   Reply with quote   Complain
Apteryx6
Contributing MemberPosts: 841
Like?
Re: Focusing in low light - Solution to a non-issue
In reply to bdcolen, May 30, 2011

bdcolen wrote:

Well...When I first received my X100 I, too, noticed that it just did not want to focus in low light. But I discovered that if the ISO is set sufficiently high to capture images at a reasonably shutter speed in a given level of ambient light, the problem disappears. Try it. I found that at 6400 ISO, 3200 ISO, and even 1600 ISO, I was able to focus without any problem in a conference room in which the only light came from a slide show projected on a screen, and the screen of the laptop running the slide show - which is to say, it was a dark room with only some extraneous light.

I can't replicate it. You should try it with a range of subjects (low contrast subjects as well as high contrast ones). It is a slight misnomer to say the X100 has a problem focusing in low light. Light level only contributes to the problem. The real issue is of focusing on low contrast subjects (but virtually all subjects have more contrast in bright light and less in low light).

With a high contrast subject (my current high contrast test subject is the box the Fuji hood and adapter came in) I can focus (using Auto ISO) on the hood box in light so low I couldn't hand hold the camera to take the picture, even at f2 and ISO 3200 (the max for Auto ISO) - the required shutter speed was 1/2 a second. But on low contrast subjects in the same light (or even in much brighter but still low light) on which I couldn't focus using Auto ISO, I also couldn't focus using the ISO set to 6400 and Auto ISO off.

I'm not saying it couldn't have an effect at the margins (a lot of things seem to, including focus distance, and using MF with AFL unstead of AF). But I don't think it is a universal answer.
--
Apteryx

Reply   Reply with quote   Complain
nand
Senior MemberPosts: 1,323Gear list
Like?
Re: Focusing in low light - Solution to a non-issue
In reply to bdcolen, May 31, 2011

I find that in low light, the X100 AF works better where there are contrasty vertical edges to focus on. When the edges are horizontal, I need to turn the camera at least 45 degrees. When it won't AF at all, it generally is to dark for a handheld shot .

Nand.

-- hide signature --

 nand's gear list:nand's gear list
Fujifilm X100S Olympus OM-D E-M5 Fujifilm X-E1 Olympus E-M1 Olympus Zuiko Digital 14-54mm 1:2.8-3.5 II +21 more
Reply   Reply with quote   Complain
Gordon L
Regular MemberPosts: 145
Like?
Re: Focusing in low light - Solution to a non-issue
In reply to nand, May 31, 2011

I don't find the camera particularly hard to focus in poor light, matter of fact, it does a better job than my Canon xs, especially with that focus led.
I use manual focus, af button, center spot only.

Reply   Reply with quote   Complain
ViewOnBlack
Regular MemberPosts: 119
Like?
Re: Focusing in low light - non-solution to a real issue
In reply to Andy Westlake, May 31, 2011

unfortunately, I will have to confirm that the X100 is really poor at low-light AF. both my GF1 and my EPL1 do much better and a lot faster. the other day, I also compared the X100 with the EPL2 (with the kit lens) and its no contest. not even close. the EPL2 is "blazing" fast and infinitely more accurate vs the X100... which is a shame. Fuji has a long way to go in this department. I just tried bumping the ISO to the max and it makes no difference at all.

Andy Westlake wrote:

bdcolen wrote:

Everywhere I look, I see comments about problems focusing the Fuji X100 in low light. Even Dpreview, which is usually spot on in its criticisms and observations, complained about this problem.

Well...When I first received my X100 I, too, noticed that it just did not want to focus in low light. But I discovered that if the ISO is set sufficiently high to capture images at a reasonably shutter speed in a given level of ambient light, the problem disappears. Try it.

Weirdly, that actually describes how I had the X100 set up when I was using it in low light - with manually-set high ISOs. Because, well, the light was low, so I needed them (and I suspect the same is true of anyone else who's commented on this). And despite this I found that the X100 genuinely struggled at low light levels where cameras like the GF1 or E-PL2 (with 20/1.7) still focus perfectly happily. The X100 tends to need a high contrast target to lock onto; otherwise it gives up and defaults to a focus distance of about 3m (so if your subject happens to be at 3m, you're just fine).

I'd also point out that there's no obvious technical reason why changing the ISO should help the AF.
--
Andy Westlake
dpreview.com

Reply   Reply with quote   Complain
Apteryx6
Contributing MemberPosts: 841
Like?
Re: Focusing in low light - non-solution to a real issue
In reply to ViewOnBlack, May 31, 2011

ViewOnBlack wrote:

unfortunately, I will have to confirm that the X100 is really poor at low-light AF. both my GF1 and my EPL1 do much better and a lot faster. the other day, I also compared the X100 with the EPL2 (with the kit lens) and its no contest. not even close. the EPL2 is "blazing" fast and infinitely more accurate vs the X100

I can easily believe other contrast detect cameras are faster to focus than the X100, or that they may focus on a low contrast subject the X100 is unable to with AF, but I don't think there is any general problem with its accuracy. Although at the start it took me a while to realise that unlike other cameras I was used to, the X100's shutter button is not focus priority. If you press the shutter fully before it has time to focus, it will still take a photo - just an out of focus one. You generally only see this in low light, because the "aperture lag" that affects the camera in bright light does lock the shutter, and in bright light it takes longer for the aperture blades to get into place than it takes the camera to focus.

-- hide signature --

Apteryx

Reply   Reply with quote   Complain
Apteryx6
Contributing MemberPosts: 841
Like?
Re: Focusing in low light - Solution to a non-issue
In reply to Gordon L, May 31, 2011

Gordon L wrote:

I don't find the camera particularly hard to focus in poor light, matter of fact, it does a better job than my Canon xs, especially with that focus led.
I use manual focus, af button, center spot only.

It seems to me (with a limited amount of testing) that in MF with the AFL button, the camera can focus on a given low contrast subject in light 1-2 EVs less (ie, requiring 1-2 stops more exposure) than it can using AF. Why? Because its the X100!

The difference is less (possibly non existant) on high contrast subjects, but they are easier to focus on in low light either way.

-- hide signature --

Apteryx

Reply   Reply with quote   Complain
JonathanJK
Regular MemberPosts: 460
Like?
Re: Focusing in low light - Solution to a non-issue
In reply to Apteryx6, May 31, 2011

I'm old school so I don't use auto-iso, and it's my preference to never use the AF-illuminator. My SLR didn't have one afterall.

I might have the odd moment where the X100 wouldn't lock focus, but I've inadvertently focused on something totally black.

Anyway, I've never had a problem using it in low light, surprised why other people have had problems.

I was worried about it before I bought it but the contrast detection system hasn't been a problem at all.

Even my old 1Dsmk2 would not focus on near darkness so to me performance is the same. I'd say the Fuji X100 is better in low light than a 5D.
--
http://jonathanjk.com/

Reply   Reply with quote   Complain
bdcolen
Junior MemberPosts: 31
Like?
Re: Focusing in low light - Solution to a non-issue
In reply to jack_h, May 31, 2011

Absolutely.

Reply   Reply with quote   Complain
bdcolen
Junior MemberPosts: 31
Like?
Re: Focusing in low light - Solution to a non-issue
In reply to Paulo Abreu, May 31, 2011

Yes, you are misunderstanding. I was shooting at f2. I am NOT an engineer, but it strikes me that as we are focusing on the sensor - just as we used to focus on the film plane - if the sensitivity of the sensor is not set high enough for the ambient light, it cannot register the image to focus it. I'm just suggesting not trying to shoot at, say, 400 iso in a room where the meter is giving you a reading of 1/4 of a second @f 2, go to 1600 or 3200 and shoot at f2 and I'll bet the camera snaps right into focus.

Reply   Reply with quote   Complain
Andy Westlake
dpreview AdminPosts: 2,915Gear list
Like?
And therein lies the problem
In reply to bdcolen, May 31, 2011

bdcolen wrote:

I am NOT an engineer, but it strikes me that as we are focusing on the sensor - just as we used to focus on the film plane - if the sensitivity of the sensor is not set high enough for the ambient light, it cannot register the image to focus it.

OK, one really, really important point you need to understand here is that increasing the ISO has absolutely no affect whatsoever on the sensor's actual sensitivity to light.

-- hide signature --

Andy Westlake
dpreview.com

 Andy Westlake's gear list:Andy Westlake's gear list
Fujifilm FinePix F30 Zoom Olympus Stylus Verve S Olympus XZ-2 iHS Canon EOS 5D Panasonic Lumix DMC-GF1 +11 more
Reply   Reply with quote   Complain
solemnportraits
New MemberPosts: 4
Like?
Re: Focusing in low light - Solution to a non-issue
In reply to JonathanJK, Jun 5, 2011

JonathanJK wrote:

I'm old school so I don't use auto-iso, and it's my preference to never use the AF-illuminator. My SLR didn't have one afterall.

I might have the odd moment where the X100 wouldn't lock focus, but I've inadvertently focused on something totally black.

Anyway, I've never had a problem using it in low light, surprised why other people have had problems.

I was worried about it before I bought it but the contrast detection system hasn't been a problem at all.

Even my old 1Dsmk2 would not focus on near darkness so to me performance is the same. I'd say the Fuji X100 is better in low light than a 5D.
--
http://jonathanjk.com/

You are absolutely right mate. I own a 5D and had a 350D before and 350D's focus was way better than 5D. But since i have used 5D and the auto-focus destroying 50mm 1.8 II i have been using manual focus almost 99% so i dont think i'd ever have problem focusing in almost any camera (my MF is quite accurate coz of practice) : )

Reply   Reply with quote   Complain
AlbertoS
Forum MemberPosts: 63
Like?
Re: Focusing in low light - Solution to a non-issue
In reply to solemnportraits, Jun 5, 2011

Every single time I have had problems focusing with the X100 because of low light, I switched from AF-S to AF-C and the problems just went away. Immediate or near-immediate focus.
--
http://www.flickr.com/photos/a-lber-to/

Reply   Reply with quote   Complain
Keyboard shortcuts:
FForum MMy threads