5d mark III focusing slowly/etc. in low light wedding receptions

[ejder]

I've been using 5d2s for a long time because I am simply not rich enough (and I don't want the huge body either) to buy 1d-series cameras for work. I've shot about 20 weddings with the 5d3 since I bought it, and I finally sent it in to Canon the other day for an autofocus checkup.

My #1 issue is reception autofocus. My 5d2s beat my 5d3 at reception focusing (with 580EX AF assist always used). They are more reliable for AI servo and faster for one-shot.

My 5d3 struggles to acquire in one-shot, taking probably close to 2 real seconds (it feels like forever) to establish and confirm a lock on a static subject during wedding receptions with lenses like 24L II, 35L, 50L. In contrast, in the exact same lighting conditions and with the same lenses and flash AF assist, my 5d2s all snap right to focus and I click the shutter within about 1 second or less, getting an in-focus image about 90-95% of the time.

With AI servo, the 5d3 is just inferior to my 5d2s in low light. I was hoping, one day, to get a camera that would give me the ability to track subjects well during processionals/grand entrances/reception dances using the outer points, because I'm pretty tired of being stuck with center-point framing for these situations. I thought the 5d3 was supposed to solve that problem, but in fact it took a step backward in low light AI servo accuracy and locking. My 5d2s (center point) both acquire faster and track better in low light than my 5d3 (center point also).

After sending the 5d3 in to get it checked (and so they could charge me $175+), I got a nice copy of the page saying that the camera focus in low light is blah blah etc. etc. use AF assist (which I had noted I did) and the overall feeling was that they were very condescending and disregarding of my equipment issue. To me, a $3500 camera should perform better than a camera that is now worth ~$1300...and so the 5d3 performs arguably better in GOOD light, simply because it has more focus points to choose from which are generally pretty accurate - in GOOD light. However, it performs worse in reception light. Wedding photographers will understand what I mean by reception light.

My 5d2 AI servo is not useless during receptions, but my 5d3 AI servo struggles more in the same reception lighting. My 5d2 one-shot locks quickly and pretty accurately during receptions, while my 5d3 takes significantly longer in one-shot to lock, and sometimes it gives me pretty wild misses, during receptions. Always using AF assist with 580EX, and btw the 5d3 firmware is the latest version (1.2.3 at this time). The camera simply focuses slower during receptions than my 5d2s, and AI servo misses more. 

I also don't like that AF points don't light up before focusing, but this is less important to me than a fast, responsive AF system for wedding receptions. I have had to put away the 5d3 on multiple occasions and bring out a second 5d2 for wedding receptions just so I can get good dancing photos, good speech/toasting photos, etc., before all the key moments went by and ohhhh too late, my focus system didn't lock in time...

I have been having this issue with 5d3 performance since I bought it close to a year ago. I do wedding photography primarily, and I have quite a bit of experience shooting weddings and dealing with the various demands of weddings.

Most of my AF experience is with single point, with only a few experiences using the expansion settings.  I have never had trouble locking or tracking with single point with my 5d2s as long as there was enough light to do it, and being used to that I expected the 5d3 to be able to perform at LEAST comparably.  It does not.

At this point, this critical functional limitation of the 5d3 has left me very dissatisfied with the camera.  I thought upgrades were supposed to do everything just as well or better than the previous version, but this newest camera has shown me that more AF points definitely does NOT mean a better (or even comparable) AF system in every situation.  Clearly something was traded off when they added a ton of cross-type points, like low light acquisition speed and being able to see your AF points illuminate when you start AF.

I've been playing around with Nikon equipment for a while and am beginning to think that is my forced alternative.  I don't like the things I hear about Nikon customer support, and I don't really like the direction they are going with some of their releases or how they handled function issues (focus issues with off-center focus points, oil on sensors, etc.) but Canon isn't innocent of that stuff either.  And if I use an all-Nikon setup then I will have excellent dynamic range at low ISOs as well.  Too bad Nikon doesn't have the glass I like best (35L, 85L, etc.)...but compromises must be made in some direction, and I'm intensely frustrated with Canon's latest cameras' focusing systems in low light.

It's very specific, mind you: Low light performance is inferior to my 5d2s.  In good light, my 5d3 has better AF flexibility for tracking with outer points, and the one-shot focus acquisition is comparable to my 5d2s.

[TCampbell]

The 5D III has far far more than simply "one shot" vs. "AI Servo".  There's a 47 page document on *just* the focus system for that camera.  Specifically, there are a number of options for AF area selection and if you've chosen a sub-optimal mode you could be forcing your camera to struggle to achieve focus.

For example... in just the "one point" style mode, there's:

• Spot AF - a reduced AF area designed to be used with HIGH CONTRAST but SMALL focus points (such as eyes).  They idea behind this reduced AF area (which the 5D Ii doesn't support) is that you can force the camera to focus on a particularly tight object (such as an eye) at very shallow depth of field without having to worry that the camera will accidentally grab either the eyebrows or nose, etc. which are at a slightly different focus distance and end up softening the focus on the eyes.  But when using this mode, the camera needs a subject with high contrast and enough light to make it easy to identify the contrast because you're dealing with a very tiny area.
• 1 pt AF - this works like the standard 1 point AF mode found on most cameras.
• Expand Area AF - this is a 1 point mode except it borrows from points above, below, left and right of the selected point to use as focus-assist points.  This aids in situations where contrast is poor (or light is poor) as it give the AF system a larger target target to help find enough contrast to lock focus.
• Surround - like Expand Area AF, this mode uses a central AF point but then completely surrounds that point with 8 additional points to expand the AF area even larger.  
• Zone AF - this mode allows the camera to use a block of AF points in a region of the display.  E.g. if you are composing your subject with a "rule of thirds" composition, you could push the AF zone over to the area where you intend to place your subject.  It's an auto-select area but the auto-select is constrained to only those AF points in the zone you pick.
• Auto-select 61 point AF - this mode allows the camera to use any AF point it wants.  However, unlike typical auto-select modes, you actually can use the joystick to tell the camera where you want it to search for it's initial focus point.  This is because this mode is commonly used in sports situations where the cameras intelligent tracking & recognition system (iTR) will be used... the camera focus will follow the subject as they move around, but there's a whole set of configurations which control how the camera expects subject movement to behave (this is a highly tunable mode.)

The AF system on the 5D II (and, like you, I also own both 5D II and 5D III cameras) has an AF system that can focus from -0.5EV to +18EV.  

The AF system on the 5D III, on the other hand, has an AF system that can focus from -2EV to +18EV.  In other words, the 5D III focuses in considerably less light than a 5D II.

The 5D II has only 9 user-selectable AF points (the 9 you can see... one center "cross type" point surrounded by 8 single-axis AF points in the diamond pattern).  BUT... it has 6 more "focus assist" points which are hidden (not user selectable).  These are not etched on the viewscreen, but they are on the focus sensor.  Two points ... one above and one below the center point, are only available at f/2.8 (so not all lenses will be able to use these).  Four addtional points form a box around the center point and these work even with f/5.6 lenses.  

This means in some situations your 5D II is using a larger focus area then you might guess.  Canon does not consider these extra points to be focus points... they are "focus assist" points in that they extend the area the camera uses to help it obtain more a larger target with which to identify enough contrast for focus.

This is why I'm thinking you've picked a sub-optimal AF area mode.  You might be using spot-AF and, if you are, you are forcing the camera to focus with a significantly smaller AF area than the 5D II (especially if the 5D II was using those hidden focus-assist points and you didn't know it).  Try using expand area AF or surround AF if the camera is struggling with low light.  

I hope this is helpful.  The 5D III is an amazing camera and easily has one of the very best focus systems in the industry. 

The Canon 6D, incidentally, has an 11 point AF system with one cross-type point, but the 6D can focus down to -3EV... a bit lower than the 5D III.  However in virtually every other way, the 5D III has a vastly better focus system.

[marcosphoto]

I can't say I'm completely impressed with my upgrade to 5D3 from my 5D2 but I can tell you that my 5D3 smokes my 5D2 body any day of the week and sunday with regards to focus speeds - cannot even compare!  However at first I did notice some lag with flash installed.  I noticed a firmware upgrade early on addressing this issue but I never saw it as a large enough problem to bother doing the upgrade right away (I prefer to do firmware only when absolutely nessesary).  However when I had the light leak problem addressed, they did my firmware for me and I can say that YES, the upgrade did improve my performance in low light with flash installed. 

Are you on the latest firmware?

[ejder]

As I said in my original post, I've been on the latest firmware ever since I got the camera.  It's been sent in to Canon to see if it's functioning normally, and according to them it is.  The 5d3 focuses slower in low light, period.  If your subject moves at ALL (or if YOU move, e.g. the target is the eye vs. the nose or the mouth of the subject just by natural movement), and you're using one-shot mode, it completely restarts the focus acquisition process, goes through the double-checking stuff all over again, and 5 seconds after pushing the AF-ON button you finally get a focus lock that MIGHT be in focus.

AI Servo in low light is basically worthless. My 5d2s track better and in lower light than my 5d3.  It's been this way since the beginning, even after Canon received and tested the camera and charged me just to tell me nothing's wrong with it.

That's the #1 reason why I don't really like the 5d3 and actually won't use it at all for several parts of the wedding day.  Unless I want 99% out-of-focus photos, that is...

I've used it for 20+ weddings now, same results every time.  I don't think the fault lies exclusively in ME - otherwise I probably would not get comparatively much better results with an "inferior" camera like the 5d2.

[marcosphoto]

Sorry, missed that part about the version - guess I was just excited to try to help out.  I personally cannot agree that my 5D2 was better at focusing low light (flash or not) - than my Mk3.  However, as I only do this sort of shooting for personal stuff and on a professional level do motorsports I think its completely possible I have not met those conditions often.  Also, I found the Mk3 so good in low light that I hardly use my flash so again I'm not an expert.  I will say one thing, repair people (present company excepted  😉  sometimes just assume the owners are crazy and don't bother doing the inspections as deeply as they should.  I feel the same about my 24-105L lens which I feel has issues but repeatedly get told it's perfect.  Not saying this is the case for you but who knows. 

Question, my olden days 430EZ flash used to emit a red beam assist while focusing however I swear my 580EX2 flash does not.  Because I don't use the flash often I am curious if these flashes are designed with a visible assist beam and if so, curious why I've never taken notice to it on my flash. 

Good luck in your search for the truth.

[ScottyP]

You are not alone in this.

Peruse the "most kudoed posts" on this site, being sure to select "all time" rather than just those of the last week or month, etc... You will find that of the first 5 pages (75 posts) about 60 of them are the following post and popular responses to this post: http://forums.usa.canon.com/t5/EOS/5D3-AF-assist-beam-slower-focus/m-p/2277

There were 180 responses in all.

I think even this is understating the magnitude because it lists the original post and all its kudos-winning responses as separate posts, rather than as one post with an insane, unprecedented number of kudos for its sub-postings. Also, In addition to this thread there were several other significant threads on basically the same issue, and if you read it all you will see at there were threads on all the other Canon-related forums.

There was a firmware upgrade and that made a lot of people's issues better but some still reported issues catching focus in low light. Weddings did seem to be the scenario most frequently used to describe the problem(s).

[ejder]

This singular issue of the 5d3 has ensured that I will never buy another one (unless they fix that, which they won't).  Unlike what I did with the 5d2 (upgraded to 5d2s towards the end of their product cycle), the 5d3 is too impaired for low light photography for me to be able to replace my 5d2s with 5d3s.  I can only hope the next generation will NOT have the same low light focus delays...otherwise I might have to buy a few 6Ds just to keep up with more current tech (since my 5d2s will wear out eventually).  I've heard they don't have the same doublechecking delay, but they also have other limits that I dislike (1/4000 ss, 1/180 flash sync, no pc sync port, SD memory only) and will have to work around.

[ScottyP]

Is there anyone out there who 1.). Had the low light focusing problem with 5d3 as described in the big thread I referenced above, and 2.). Used the firmware upgrade?

If so, did it a.). Fix the problem or b.) not really fix the problem?

I actually bought the 6d instead of the 5d3 for the sole reason of that problem. I had the money, I was planning on buying the 5d3 on that Black Friday sale, but I changed my mind and went 6d for the low light focusing. I had experienced bad low light focusing with my old T3i and that was the biggest issue for me since I shoot indoors a lot.

I had been assuming the firmware upgrade had fixed the issue, but re-reading the old thread, and looking at some newer posts, I see that may not be the case. I have been thinking of upgrading to a 5d3 at some point, either a used one or maybe this coming Black Friday if there is a great deal to be had. It seemed like half the world chimed in on the old thread, and I was wondering how people, particularly any who actually had the problem, but also those who never did, are faring today, a year or so on.

[linbs]

I have the same problem since I bought my 5d mark iii about a year ago... I bought it for concert and music club photography and being a Nikon shooter I couldn't find appropriate camera in Nikon range at that moment and Canon looked reasonable... so am swearing non-stop since... for a long time I thought that I was doing something wrong but after few months of studying all possible sources of information on the camera I believe I understood most of what I need... and my final oppinion is - 5d mark iii is the worst camera I ever used for low light action shooting... it works ok in good lighting and especially in studio... I believe, that for a camera of this level and price range is not good enough...

[TCampbell]

My 5D III performs outstandingly.  The OP who created this thread some 6 months or so back, never did address the question of which focus mode was being used, nor which lens, etc.

I'm shooting with mostly all f/2.8 glass (when I do concerts I will also often grab my EF 135mm f/2L)  But this means I'm already getting more light and using more focus points than someone with an f/4 lens or a variable focal ratio lens.

HOWEVER... I'm also not using 1 pt "spot" AF.  That would be mis-using the equipment.  In low-light, llow contrast, use one of the two "expand area AF" modes in which the AF points near the select points behave as AF-assist points to help identify contrast in low-contrast situations.  This is one of the reasons why the camerra has a superior AF system.

I also have a 5D II and, yes, it works well in low-light also.  But the 5D II has hidden focus-assist points and it's automatically using them (you don't actively switch them on or off like you do on the 5D III).

The 5d III is an "advanced" camera for advanced skill photographers.   It's got 6 different variations in how to select and use the AF points.  It's also got numerous various in focus-tracking (for servo modes).  But the reason I say it's an advanced photographer's camera is becuase it's always going to do what the advanced photographer tells it to do (including when they pick the wrong mode for the situation at-hand.)  

While it's somewhat important to understand that there are 6 different variations in how to select AF points... what's even more important is to understand why the camera has so many options.  Make sure you understand the difference and in what situation you would want to use "spot AF", vs "single point AF", vs. "surround area AF"... and you'll really start to appreciate the capability of the advanced focus system.

I say this, because owning both cameras, there are pretty much no situations in which my 5D II can outperform my 5D III with AF system performance and regardless of light levels.