5D Focus freeze? Is this a fault?

I sometime my 5D can't secure focus and the lens just hunts. This is generally in low light.

I have two solutions.

1. Switch off the camera then on again and itsnaps to focus 60% of the time.

2. Switch to MF and take the picture.

Maybe fn 4 should replace my second solution.

Asher

Are you using the center point, are you looking for areas of good contrast, i.e. where there is a good contrasty 'line' to focus on? The 5D is not world beating in low light by a long stretch but if you look for a good contrasty area to focus on then it helps. If you are using a flash then you can of course use the focus assist, even buy an ST-E2 for focus assist only, it's a lot smaller than I thought it would be and have toyed with the idea while still hoping for a sucessor to the 5D with decent low light focus!

Thanks Ben,

Ben Rubinstein said:

areas of good contrast, i.e. where there is a good contrasty 'line' to focus on?

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Yes I do that! I even put my split focus screen center over an edge.

Ben Rubinstein said:

focus assist, even buy an ST-E2 for focus assist only,

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The ST-E2 is one of my tools when shooting an array of Canon flashes.

However, I'd love to use it without firing a flash. Can I do that?

A friend uses a laser to create a spot (like you see on TV when the swat team target to kill)!

Asher

Asher

Interesting this very old extract from Luminous Landscape

Fixing the D30's Focus Problems

As good as it is the Canon EOS-D30 and D60 have a serious flaw. Their ability to focus in low light is quite poor. As D30 and D60 owners will have noticed there is a white focus assist light built into the camera that illuminates when there is difficulty autofocusing. Frankly, this light hardly provides any benefit (if it even does so at all) and is an annoyance rather than an asset. The infrared autofocus assist lights as used on previous Canon cameras, such as the A2E, did a much better job. The white light is also an attention-getter and distraction to subjects, both animals and people, and consequently many users have disabled it by using Custom Function 5.

Since the the D30 and D60 reached the market there has been much discussion about how to fix the problem. One solution is to select and use only the central focus point. This is the most sensitive of the three points and it's a significant improvement to simply use the central point to focus, and then re-frame the shot.

Infra-Red to The Rescue

Another alternative is to always keep a Canon 550EX or 420EX flash unit mounted on the camera. These have an infra-red focus assist light built-in and make autofocus possible, even in total darkness. Of course this is a non-starter of a solution, since who needs the bulk and weight of a flash unit onboard simply to aid autofocusing?

Fortunately Canon makes a solution, and an elegant one at that. But it will cost you about USD $200. This is the ST-E2 Speed Light Transmitter. This is a small device, about the size of a package of cigarettes. It mounts on the hot-shoe of the D30 or D60. Turn it on and it emits a powerful infra-red focus assist beam when needed. The D30 (or the EOS-3 or EOS 1V or 1D or 1Ds) will now focus in complete darkness if needs be.

Well, i'll try it without the flash!

Any special CF to set?

Asher

The ST-E2 will only activate external flashes, it doesn't have any flash unit built in, rather it sends a focus assist light and pulses IR to transmit to other flashes. Actually you can use the focus assist alone on canon flash units without the flash unit firing, it's a CF in the 30D/5D bodies but strangely absent from the 1 series.

Asher, I admit I've never had that happen and I shoot at times in very low light. I'm curious what lens you are using when this happens. I have had the STE2 since my D30/60 days and did use it (and also my 550EX without flash) then for exactly that purpose but have never had that problem when shooting with any of my fast primes (often the 50 f/1.4 or 28 f/1.8). Maybe there's something else going on--

I also just reread your post and you say 'generally in low light' leading me to believe that it occasionally happens in good light. I can't think this is any kind of normal condition. This has never happened to me--even hunting in low light really never happens to me with fast lenses. I do have my cf.4 set to 1--and have used that for years. I have never thought about that having any effect on AF in low light though. I generally use center AF point--though at times I jog to another focus point and use it, but in low light I always use the center point.

Diane

Hi, Asher:

Here's an excerpt from a post I made on the RG forums a couple of years ago that may be helpful to you:

Focusing aids: EOS-1D class DSLRs and the EOS 5D do not have a built-in AF Assist beam. The EOS 10D, 20D and 30D do, but it exists in the form of a stroboscopic burst from the built-in flash. This method can be effective over a limited distance range, but it is annoying to most human subjects, and thankfully unavailable when using an EX Speedlite. For best low-light AF performance with these cameras, we strongly recommend the use of the near-IR AF Assist beams built into EX Speedlites and the Speedlite Transmitter ST-E2. These devices project a red, patterned beam onto the subject and are effective over varying distance ranges depending on the accessory you choose. Speedlite 550EX (or 580EX) has the most powerful AF Assist beam. It is typically effective at distances up to approximately 10 meters/33 feet or more. However, the camera MUST be set to One-Shot AF in order for the AF Assist beam to function. Speedlite Transmitter ST-E2 provides an AF Assist beam without firing a flash, so it’s useful for non-flash photography in low light. If that is your objective, be advised to stay away from Program mode on the camera, since the lowest shutter speed will be limited to 1/60 second, resulting in massive underexposure in low light without flash. Pick any other exposure mode, but stay away from Program in low light unless you are using flash.

Best Regards,

Chuck Westfall
Director/Media & Customer Relationship
Camera Marketing Group/Canon U.S.A., Inc.

Thanks so much Chuck and everyone!
I have never used the STE-2 like that and it's a great idea. I'll then know whether or not something else is going on.

Asher

As an aside, the 50 1.2L is perhaps the most enjoyable lens to use!

For portraits there's a great intimacy. Flash interferes with that mood!

Asher, I don't have the 50 f/1.2 but I agree about flash spoiling the mood--in almost everything (I don't do portraits). I only use flash for my commercial interior shots where the Canon flash system works great for me (it has to be portable and quickly and easily moved by me)-- use 3/4 Canon flashes on stands with umbrellas there--but for all my personal shooting its available light only.

Diane

Diane,

I like to use two 550 EX shooting through umbrellas to each side and one flash on the camera in between for models with a necklace or earings.

The combo of natural light and the Canon flash is great.

I also have used 3 Canon flash with the STE-2 for shooting very long tables at an executives party and for large group shots. It works amazingly well.

Asher

Does anybody know the way of combining Pocket Wizards with Canon Speedlites and/or STE-2?
Or they operate on totally different protocols?
TIA

Asher, if you are getting focus lock problems with the 50mm 1.2 then your camera needs to go for repair, when there is that much light coming in there is no excuse not to obtain a focus lock assuming enough contrast (i.e. not a blank wall). I was shooting today at ISO 3200 1/60 f1.8 (pretty dark!) with my 85mm 1.8 and it didn't miss a beat on my 5D.

Asher Kelman said:

Diane,

I like to use two 550 EX shooting through umbrellas to each side and one flash on the camera in between for models with a necklace or earings.

The combo of natural light and the Canon flash is great.

I also have used 3 Canon flash with the STE-2 for shooting very long tables at an executives party and for large group shots. It works amazingly well.

Asher

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I can see that---I don't do that type of shooting so have never had the occasion to try that. I also rarely have natural light (I wish LOL) in my commercial shooting (furniture/textile industry).

Diane

As we're on the subject, can someone tell me how, when one is using the ST-E2 as a focusing aid and not triggering a flash, you inform the camera of this so that it doesn't automatically assume there is a flash and set itself accordingly?

I have found the only way round this is to drop into Manual mode on the camera, which is a shame in constantly changing light

David

What do you mean by 'set itself accordingly', are you referring to NEVEC? Otherwise with non 1 series bodies it's a custom function, 5 I think.

Nikolai Sklobovsky said:

Does anybody know the way of combining Pocket Wizards with Canon Speedlites and/or STE-2?
Or they operate on totally different protocols?
TIA

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AFAIK they cannot communicate. One might be able to trigger the wizard simutaniously and then have a delay to allow for the Canon preflash and have the Wizard trigger the larger strobes in the whole ballroom, for example.

Meanwhile the subjects are lit with the on camera flash, for example.

However, I don't think that the Canon could adjust itself for the external strobes power unless it also is on during the Canon preflash! Too much to ask for!

I've used a Wein flash sensor to trigger strobes with light from the Canon Speedlights. However, even with the timer (one has to set dip switches), the system works much of the time!

So the Wizard will make this link bullet proof!

Asher

Ben Rubinstein said:

What do you mean by 'set itself accordingly', are you referring to NEVEC? Otherwise with non 1 series bodies it's a custom function, 5 I think.

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With a working ST-E2 on the camera, it calculates exposure based on there being a flash, it will default to the flash settings (1/60th I think) also the flash indicator lights, which of course we don't need as there won't be a flash going off.

On the other matter, you can get an ST-E2 to trigger (some) slave units by covering the 4 extra contacts with electrical tape

David

It will do that in P mode but certainly not in Av or Tv.

Covering the contacts will defeat the purpose, those contacts tell the unit to emit the assist light!

Ben Rubinstein said:

It will do that in P mode but certainly not in Av or Tv.!

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Have you tried it? it does on my cameras

Covering the contacts will defeat the purpose, those contacts tell the unit to emit the assist light!

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It works to fire non Canon units, which was the point of the question

David

Which contacts?

Asher

Asher Kelman said:

Which contacts?

Asher

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The 4 in a square

David

You must have a CF enabled which prevents the shutter speed dropping, I use Av at low speeds the whole time with flash, did a whole bunch with it yesterday at a 1/10th for example.

I've used the ST-E2 quite a lot for focus, but as mentioned, you need to be in manual exposure mode.

Which for ME is fine. I mean, we're talking about situations where the light is poor to START with, right?

This is also why I carry a small maglight in my bag.

Kevin Bjorke said:

I've used the ST-E2 quite a lot for focus, but as mentioned, you need to be in manual exposure mode.

Which for ME is fine. I mean, we're talking about situations where the light is poor to START with, right?

This is also why I carry a small maglight in my bag.

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I didn't think I was going mad

Problem is, when you need the ST-E2 for focus it is often in a place with very changeable light and having to use manual is a pain

David

The ST-E2 is a great focus aid for one shot situations. It does slow down the system on both my 5D and on my 1D mark II N. A couple of days ago I tried to use the 5D as a second body for basketball. Even in a bright venue (Jobing.com Arena) the 5D focus system on servo is so slow, the focus points so spread out and the unlit center focus point is so small that the camera (or maybe just my ability to use of it!) was virtually useless for action sports.

I have no gripes here as the 5D is for T&I and non-sports shooting. The 5D shots of the arena from the upper deck taken with a 17-40 f/4 are beyond anything my N could ever produce of the same scene. Each camera to its own, now how 'bout that FF 1D Mark III N

Rather than switching off the camera you may find that releasing whatever button activates AF and pressing it again will help more.

Choosing the best sensor for the job helps too, if your lens is bright enough to allow high-precision AF to operate.

Does the 5D have a personal function that disables lens search in case of lost focus ? The 1-series bodies do. Disabling the lens search helps because once it starts searching in poor light the camera often has little chance of getting the focus right. It works in good light.