Focus speed of 50 1.2

[rab_l]

I shoot a lot of very low light stuff with a 50 f1.4 on a 5D, however it I miss a lot of images as it has a

tendency for the focus to go walkabouts in low light, running backwards and forwards trying to lock on,

all of which takes a lot of time. My question is, does the new 50 f1.2 offer significant improvements in this

area over the 1.4. Optically I'm happy with the 1.4, but the price would be worth it if the 1.2 focuses well

in

low light. Thanks.......Robert

[stephen sullivan]

1.4 vs 1.2: I don't know. Have you tried switching to, "AI Servo?"

[fotograf]

I doubt if the 50 1.2 would be faster focusing than the 50 1.4 you now have. It's heavier glass and nearly 5 times the cost of your present lens. What exactly are you photographing, that makes your current lens "hunt" when focusing?

[steve_dunn2]

<p>Your subject says focus speed, but your text complains of problems locking on.</p>

 

<p>I have the 50/1.4. I've played with the 50/1.2 a couple of times, but not enough to have a solid feel for how its focus speed compares to that of the 50/1.4. My gut feel is that the 50/1.2 is probably slower. If it's faster, it can't be faster by much; the focus speed of both of these lenses is way behind that of my faster-focusing lenses.</p>

 

<p>As for locking on, I haven't had this problem with the 50/1.4 on any of the three bodies with which I've used it (Elan II, Elan 7E, 20D), but then again, I don't usually use it in low light; I usually use it when I want shallow DOF. I've read of others having the same problem you report. I haven't seen any reports, positive or negative, about the 50/1.2 in this regard, but given how recent this lens is, and how small the market is for it compared to other lenses, there haven't been a lot of reviews posted yet.</p>

 

<p>Have you tried manually pre-focusing? If the lens is already focused to a distance close to what's correct, maybe AF will lock on more reliably. Just a thought. And, unfortunately, frequent pre-focusing with the 50/1.4 may be bad for its longevity; the focusing hardware in this lens is well known for being less than robust, and frequent use of FT-M seems to lead to a higher failure rate. The 50/1.2 likely wouldn't suffer from this problem since it uses ring USM; the 50/1.4 uses micro USM and has to use unique hardware to allow it to have FT-M, and it's this hardware that seems to have problems.</p>

 

<p>Another thought: do you have an AF assist beam to aid in AF?</p>

[damian_tinsley]

I have issues with my 50mm f1.4 hunting in low light that I don't get with the 17-40 or the 24-105. I must say this surprised me a lot at the time. If anyone has insights as to why this should be the case I'd be very interested (no desire to hijack the thread though)

 

Damian

[rab_l]

I'm not sure if I can post an image here, I'll give it a try, but I use this lens a lot at wedding

receptions taking candid shots, and try to avoid flash as long as I can, but this often

means shooting images at 1600 iso, wide open with shutter speeds around the 20th of a

second mark, I use the star button to focus with, and have to blip it quite often, as at

these apertures even slight movment of subjects loses the critical focus I need on the

eyes. What's promted me to consider the 1.2, is I recently bought the 70-200 f4 is and

have been amazed at how well it focuses in low light, much better than my 2.8 24-70,

which in turn is better than the 50 f1.4. The 5d doesn't have a focus assist beam and even

if it did I would alert my subject so would be a no go anyway. It's a shame because I love

working with this camera lens combination, it can produce some great results, but I was

hoping that the 1.2 might focus more like the 70-200. Thanks for the replies.<div></div>

[eos 10 fan]

"The ring-type USM drive is very fast. The AF accuracy is just Okayish on the EOS 350D but that?s surely more a fault of the camera?s rather mediocre AF rather than the lens. According to Johan (the owner) the lens is spot on when used on the EOS 5D. Full-time manual (FTM) override in one-shot AF mode is naturally also available." http://photozone.de/8Reviews/lenses/canon_50_12/index.htm

 

--

[buck_rogers1]

I may be wrong but I think your 5D has 4 'invisible' AF points around the center that are only active in AI Servo mode. Try that. FWIW I sold my 50 f/1.4 partly because the AF speed and accuracy sucked bit time.<p>Your body should be able to focus at the light level you indicate (f/1.4 1/20s ISO1600=1.3EV) since it allegedly will AF down to .5EV. You might look at a 1-series as they focus in 0EV light.

[guy_kisling]

Robert, I shoot a LOT of indoor volleyball. It's all low light, high ISO shooting with AF and fast shutter speeds. 1600-3200 are where 95% of my images take place. I use a Mark IIn with AI Servo and the star button as AF-ON.

 

The following comments assume that ISO is 1600-3200, AF is used for focus, and that the lens is being shot wide open. I'm sure that these comments might be different if the lens was stopped down, the ISO setting were different, and AF or MF were being used differently. But that's not what works under the conditions that I shoot:

 

85 1.2L (not version 2) - AF is slow. Image quality is very good. 1.2 aperture is extremely helpful. I MUST prefocus the lens in order to get any AF performance under rapidly changing conditions. Good.

 

85 1.2L II (new version). AF is moderate. A definite improvement over the original version. Image quality is excellent - sharp and contrasty at 1.2. Prefocusing the lens yields more useable shots, but I often get some really good shots just using AF alone. Excellent.

 

50 1.4 - AF is moderate. Image quality is below average (remember, I am shooting at 1.4). Lens does not need to be prefocused to get some great shots, but images are soft and lack contrast. Fair.

 

50 1.2L (new version). AF is moderate. No real difference from the original. Image quality is dissapointing. I expected it to rival the 85 1.2L II image quality. Shooting many side by side shots under the same conditions, I was unable to tell the difference in the printed image (or even on the screen) between this version and the 50 1.4. I had high hopes for this lens - they did not prove out. I returned it. Fair.

 

135 2.0L. AF is Very Fast. Image quality is excellent. I wish it went down to 1.4, but then it would be very large lens. Excellent.

 

70-200 2.8. AF is Fast. Image quality is excellent. Only limitation is that 2.8 just isn't fast enough, even at 3200 ISO, the majority of the time. Very Good.

 

Recommendation: try out the 85 1.2L II if that focal length will work for you. However, I do not believe that it will AF any faster than the 50 1.4 that you are currently using.

 

As for the "hunting" problem in low light, this is more a Canon issue. All of the Canon lenses that I have shot at 1.2 to 1.4 will hunt in lower light at times depending on the subject and background conditions. I believe that Canon knows about this and has tried to address it with the new Mark III body. I have found it helpful to AF on a spot of my suject that has sharply contrasted colors or lighting.<div></div>

[PuppyDigs]

"I have issues with my 50mm f1.4 hunting in low light that I don't get with the 17-40 or the

24-105."

 

I had the same problem with mine. Oddly, almost any other lens, prime or zoom, did better

in low light. The only worse lens was my old EF 100-300 5.6L.

 

Incidentally, you might consider the EF 85 1.8 USM. AF rips and is excellent in low light.

Image quality is better than the EF 50 1.4 USM and it costs about the same.

[fotograf]

I've used the 50 f/1.4 before and never had this issue. I've also used it indoors- in hotel rooms, and even very dark churches. Focus was very fast and not an issue for me. I suppose there could possibly be an issue with individual lenses and quality control.

[guy_kisling]

For me, AF is set to center-point focus. I do not use the multiple AF point settings.

[William Michael]

I (too) assume the question relates to focus hunting rather than focus speed.

 

I use the 50mmF1.4 a lot on a 20D and in low light.

 

Yes, the focus does hunt sometimes in low light: also in reasonable light.

 

Anecdotally it seems to be because of lack of CONTRAST on which to lock rather than lack of light: I have minimized the issue by using the centre focus point only and using focus and recompose, initial focussing upon an high contrast area the same distance away.

 

Near the bottom of this link are four examples with technical information: http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00Kyko

 

RE Focus Speed:

 

I have not used the 50mm F1.2L, but (if it is FWIW, the 50mmF1.0L focuses more slowly than the F1.4, which as I understand was one issue that Canon wished to address with the newer F1.2L)

 

WW

[rab_l]

Thank you very much for all the information, I think from Guy's experience the 1.2 might not

be worth the extra spend. I do currently use the 85 1.8, which is very good, but more often

than not, I'm working in too close for this focal length, it might even be better for me to look

at the 35 1.4, but at least I have a clearer idea now of what my options are. Cheers.....Robert.

[pbizarro]

My experience is that the 50 1.2 focuses a bit faster, and more surely, than the 50 1.4. This is using a 1V.

[yakim_peled1]

As far as AF speed goes, the 28/1.8 USM and 85/1.8 USM are significantly better than the 50/1.4 USM. Ring USM and IF design make a huge difference. My next lens in that range will be the 35/1.4 USM L which also has both.

 

 

Happy shooting,

Yakim.

[patricks]

i have the 50/1.2 and the AF speed is not that impressive, but then again, that is not the reason to own/use this lens. i'd say that the AF capabilities of the Canon consumer/prosumer line like the 30D and 5D isn't top notch.

[rab_l]

Patrick I don't mean this to sound provocative, but an honest question, what is the reason for

buying this lens.