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Rooz
03-29-2009, 04:13 AM
i'm pretty sure that canon bodies dont have a dedicated AF motor ?? in nikon bodies, the D3 and D3x etc have a more powerful motor than the consumer models. so my question is, do all canon bodies generate the exact same AF speed in lens' ? ie: does a 1D body AF say a 35/1.4 faster than a MkII ?

thanks.

GaryS
03-29-2009, 06:58 AM
You are correct Rooz, Canon's EOS system has all the motors in the lenses, so a lens moves at the same speed regardless of body.

michaelb
03-29-2009, 07:08 AM
You are correct Rooz, Canon's EOS system has all the motors in the lenses, so a lens moves at the same speed regardless of body.
True, but AF acquisition does vary between bodies.

Csae
03-29-2009, 01:21 PM
So in reality, your lens will focus faster on some bodies not because of the difference in motors, but the difference in algorithms and processing power to tell those motors where to go.

cdifoto
03-29-2009, 01:25 PM
In Canon, the camera does the finding and the lens does the moving. That's why we like USM so damned much, and why we have problems with third party non-USM stuff.

Rooz
03-29-2009, 04:06 PM
is there more than 1 type of USM motor ? why does the 35/1.4 focus slower than the 24-70 ? or is that just my imagination ?

cdifoto
03-29-2009, 04:11 PM
There's ring USM and micro-USM. Both the 35L and 24-70L have ring USM. It's probably your imagination. My limited experience with the 35L was that it focused faster than my 24-70. Not by much, but faster nonetheless. That could have been MY imagination though.

Rooz
03-29-2009, 04:16 PM
so ring is the better one ? (faster)

cdifoto
03-29-2009, 04:37 PM
Ring is better than micro, yes. Micro USM is in lenses like the 50mm f/1.4. It's faster than the non-USM motors but it's not up to the par of ring USM like in the 85mm f/1.8. As far as I know micro USM isn't used much anymore and was just a cheaper early version of USM.

laydros
03-29-2009, 05:10 PM
What other lenses have micro USM? I have heard that the 50 f/1.4 is one of the only micro motor USMs with FTM focusing, but I can't recall reading about any other micro USM motors.

Does this mean that a 24-105L and a 28-135 are going to focus at the same speed?

The 35L should be faster than the 24-105L on many bodies because most have more sensitive AF at f/2.8 and faster.

michaelb
03-29-2009, 05:40 PM
All of my Canon lenses are quite fast to focus, but my 50 1.4 is the loudest/slowest due to micro-USM rather than ring USM. All of my lenses focus a little faster on my 40D than my 5D. My Sigma 100 is the slowest and loudest of all my lenses, but it seems very accurate.

Rooz
03-29-2009, 06:04 PM
thanks guys. michael, i'm not after "quite fast", im after blistering. ;)
as pointed out above, i think this may have more to do with the bodies AF system.

cdifoto
03-29-2009, 06:14 PM
One person's "quite fast" is another person's "blistering"...

RichNY
03-29-2009, 06:21 PM
thanks guys. michael, i'm not after "quite fast", im after blistering. ;)
as pointed out above, i think this may have more to do with the bodies AF system.

I've only found blistering with the 1DMIIN and D3. The D300 AF is decent but significantly slower than the pro bodies.

michaelb
03-29-2009, 06:25 PM
One person's "quite fast" is another person's "blistering"...

Agreed.

I mostly shoot in single shot mode and AF is very fast for all my lenses, but when I really notice AF speed is when I shoot in AI-servo. In servo mode my 40D seems faster than my 5D, but the 5D does fairly well considering.

Some of my lenses are a bit faster than others though. I think my 200 f/2.8 is the fastest and it easily could be considered "blistering" fast.

But to really appreciate the speed of these lenses I think you need to mate them to a 1D body, especially if you are shooting in AI-servo.

Mark_48
03-29-2009, 06:47 PM
Any comments on how Sigma's HSM compares with USM of Canon? The HSM lenses I have are pretty quick focusing and seem to have less trouble in low light than my non-USM/HSM lenses.

cdifoto
03-29-2009, 06:58 PM
Any comments on how Sigma's HSM compares with USM of Canon? The HSM lenses I have are pretty quick focusing and seem to have less trouble in low light than my non-USM/HSM lenses.
The only experience I have with HSM is on my Sigma 12-24 and my former Sigma 50-500. The 12-24 has such a short throw I can't imagine it'd even be slow without HSM (the Tokina 12-24 wasn't slow). I shot sports like dirt track racing, field hockey, soccer, and volleyball with the 50-500 with pretty good success.

Based on my limited experience I'd say it's on par with Canon's USM. Or darn close.

Rooz
03-29-2009, 08:36 PM
I've only found blistering with the 1DMIIN and D3. The D300 AF is decent but significantly slower than the pro bodies.

i agree, on a d3 there is a jump in performance but thats due to the sixze of the motor, not the AF system which is identical to the d300. it gets back to my inital question. if all bodies focus the same in canon, (lens speed), then there shouldnt be that much of a difference on the body...unless the AF system used in quite slow compared to the higher end...which is what appears to be the case.

i think my expectations for lens focus speed may just be unrealistic. i'm after a prime that focusses as fast on an FX body as the 24-70 does on my d300. nikon dont make the 35/1.4 and on the 5DmkII its not as fast as i hoped. so i guess my only option is to marry the 35/1.4 to a 1D body or for nikon to make a proper 35/1.4.

downtrodden
03-29-2009, 08:58 PM
Well why ya gotta be so picky Roozy-Boy? Lord...

:D

Rooz
03-29-2009, 09:04 PM
lol .......

RichNY
03-29-2009, 10:04 PM
i agree, on a d3 there is a jump in performance but thats due to the sixze of the motor, not the AF system which is identical to the d300. it gets back to my inital question. if all bodies focus the same in canon, (lens speed), then there shouldnt be that much of a difference on the body...unless the AF system used in quite slow compared to the higher end...which is what appears to be the case.

i think my expectations for lens focus speed may just be unrealistic. i'm after a prime that focusses as fast on an FX body as the 24-70 does on my d300. nikon dont make the 35/1.4 and on the 5DmkII its not as fast as i hoped. so i guess my only option is to marry the 35/1.4 to a 1D body or for nikon to make a proper 35/1.4.

Just accept it is time to go D3 or add a D2X to your kit :)

What the heck are you trying to photograph that neither Canon or Nikon can provide on their own?

downtrodden
03-29-2009, 10:16 PM
What the heck are you trying to photograph that neither Canon or Nikon can provide on their own?

He's trying to prove those things he sees in the corner of his eye is real, every time he turns his head though- it's gone... those damn things are fast! so.. he needs speed.

Someone should let his wife know he's off his meds. :eek:


:cool:

cdifoto
03-29-2009, 10:17 PM
I thought he was just trying to find out if the refrigerator light actually goes off when the door is closed.

downtrodden
03-29-2009, 10:20 PM
Lord only knows with those crazy Oz boys, ya know? i'm just saying- Mrs. Roozy should keep him medicated... I'm just saying.

:D

Csae
03-29-2009, 10:47 PM
Im not really sure why you'd need a blistering fast 50mm...

Action shots usually require a greater range then that, but hey your ball.

Focusing does happen alot faster with only the centerpoint selected, especially on some fast f2.8 and faster lenses. Its stated in some manual somewhere, since alot of canons have some "invisible" points and stuff related to that.

Rooz
03-30-2009, 12:08 AM
What the heck are you trying to photograph that neither Canon or Nikon can provide on their own?

i want a 35/1.4 and an 85/1.4 that have the same AF mechanism that the 24-70 have. nikon dont make a 35/1.4 and the 85/1.4 is screw drive. (i can live with an 85/1.8 as long as it focusses fast.),so in short i want the canon primes on a nikon body. lol

if nikon actually updated their prime lens' properly, (not the half assed effort of the 35/1.8), then i wouldnt have this problem.

for the canon guys, you need to understand that the difference in AF speed betwen the 24-70/2.8 and nikon primes is night and day.

cdifoto
03-30-2009, 12:31 AM
The EF 85 1.8 definitely focuses fast. The 85 1.2L does not, despite having ring USM (supposedly too much glass to move quickly). The 35L also focuses very quickly, but I've never experienced a Nikkor 24-70 nor do I know what your definition of "blistering" is.

Rooz
03-30-2009, 01:25 AM
nor do I know what your definition of "blistering" is.

just like the 24-70/2.8L or the 70-200/2.8L. bloody fast.

cwphoto
03-30-2009, 06:24 AM
Focus manually ya wimp. :rolleyes: :D

faisal
03-30-2009, 07:31 AM
I don't find the focusing on my borrowed 85mm f1.8 as fast as my 10-22mm...is it a bad copy or am I doing some thing wrong or it's something to do with the focal range of the lens???

dr4gon
03-30-2009, 08:09 AM
Focus manually ya wimp. :rolleyes: :D

Rooz likes his uber fast AF :p.

michaelb
03-30-2009, 09:31 AM
FF and ultra-fast focus? 1DsII.

My 24-105 f/4 and 70-200 f/4 seem to foucus just as quickly as my primes.

RichNY
03-31-2009, 07:33 AM
i want a 35/1.4 and an 85/1.4 that have the same AF mechanism that the 24-70 have. nikon dont make a 35/1.4 and the 85/1.4 is screw drive. (i can live with an 85/1.8 as long as it focusses fast.),so in short i want the canon primes on a nikon body. lol

if nikon actually updated their prime lens' properly, (not the half assed effort of the 35/1.8), then i wouldnt have this problem.

for the canon guys, you need to understand that the difference in AF speed betwen the 24-70/2.8 and nikon primes is night and day.

The 85 f/1.4 is a screw lens but it isn't a pig at focusing by any means; I have used it shooting horse racing with excellent results. It falls somewhere in between the Canon 85 f/1.8 and f/1.2 -- but definitely closer to the 1.8.

I was also pretty happy with the Sigma 30mm lens; have you looked into that as an alternative to a 35mm?

Is there really something you are looking to shoot that your 14-24, 24-70, 70-200 is not capable of delivering?

Other that when using my 200 f/2 and 400 f/2.8 for sports I don't find the need for blistering fast AF. I've never felt that capturing the types of images I take were an issue with the Sigma 30, Nikon 50, or Nikon 85.

VTEC_EATER
03-31-2009, 07:59 AM
Is it just flat out focus speed, or focus acquisition?

I would take focus acquisition over focus speed any day of the week, and from what I hear about the 5DmkII... Its still not the best at its focus acquisition. Certainly not up to par with the 1D series cameras. Also, the 5DmkII may have some great ISO, but I have heard it can't focus for sh!t in low light situations, where high ISO is required. What good is that? From what I have read, the 1D series cameras are much better at low light focus acquisition.

With that said, the high end Nikons all use the same CAM3500 engine for its focus (as you know), and the D300/700/D3 all have relatively equal focus acquisition because of that. The D3 may be a little better, but its still pretty marginal. The key is setting up the focusing engine correctly to work best for the situation. 51 A/F points is cool, but way confusing for the camera to use in a sports situation. Turn that thing down to 21 or 9 AF points. Start using focus groups. These adjustments will greatly speed up your focus acquisition and give you waaaayyyy more keepers.

I feel your frustration with Nikon and their lack of AFS primes, but what good is a lightning fast auto focus motor in a lens, when the camera can't find anything to focus on? When I think about it this way, I'm much happier with my choice of Nikon, and especially for upgrading to the D300.

erichlund
03-31-2009, 08:06 AM
Rooz has become something of a prime snob. ;) He actually used the words not sharp enough about the 24-70. It's a sickness, and we're trying to get him help, but there you have it. (Of course, when I find that help, I'll have to get just behind him in line. There's something to be said for a light weight lens that is fast, accurate, and gives better corner to corner performance than just about any zoom [14-24 excluded]).

Of course, if he'd stop feeding so much coffee to his kid, he might slow down enough that a mortal lens would work. ;)

laydros
03-31-2009, 10:01 AM
Yeah, that Nikkor 24-70 is just slushy huh?

I should make my wife read this thread. She is upset I bought a used 40D and want to get a 70-200 f/4. In my little world that 40D is a Ferrari!

I guess one difference so far is my kid isn't even crawling yet. Maybe if I get her moving Katy will better understand my need for USM focusing.

Edit/afterthought: But then again, it sure is a quick moving addiction. I remember only 6 months ago saying something about buying a 30D, and laughing at it as an absolutely preposterous proposition. Now I sit here with a 40D, a Rebel, and several hundred dollars worth of other stuff.

Rooz
03-31-2009, 02:53 PM
The 85 f/1.4 is a screw lens but it isn't a pig at focusing by any means; I have used it shooting horse racing with excellent results. It falls somewhere in between the Canon 85 f/1.8 and f/1.2 -- but definitely closer to the 1.8.

horse racing isnt the same issue. they are moving in one direction.


Is there really something you are looking to shoot that your 14-24, 24-70, 70-200 is not capable of delivering?

the 14-24 is perfect, i dont have the 70-200 and the reason i dont like the 24-70 is not cos it cant deliver the results...it can. i just dont like using it and i want something with a wider aperture.


Rooz has become something of a prime snob. ;) He actually used the words not sharp enough about the 24-70. It's a sickness, and we're trying to get him help, but there you have it.

lol i did not. i have never criticised the lens optically. its superb.

erichlund
03-31-2009, 04:59 PM
I know you don't like the handling. Perhaps it was one of the "competing" 24-70s. Still, bad words about one of Nikon's Icons. Better be keeping a lookout over your shoulder.

Nikon is a zoom lens company. They sorta said so when they claimed results as good as any prime about their new 14-24, even if it is true. I just sorta goes to their whole attitude.