Canon 1K MK IV - Accuracy of Outer Focus Point

[markjhn]

Im trying to get a consensus regarding the use of the outer focus points on primarily the Canon 1d MK IV, though would love to hear from Nikon users as well.  Having shot with the 5D while waiting patiently for Canon to upgrade their focusing systems, I put up with it's sluggish shutter lag and long black-out times, along with it's closely centered 9 focus points.  Most anticipated about the MK IV was being able to use the outer focus points rather than using the center and recomposing method which tended to not always suit what I was shooting, as well as producing soft or completely missed shots.

I purchased the 1D MK IV last month and it's been back to Canon for it's second time due to inaccurate focus.  While the reviews of it's AI Server II AF and tracking abilities have been glowing for the most part (there have been reported questions and inconsistencies; read Galbraith among others) I typically don't use it in AI Server, but instead use One Shot AF and it's outer focus points so I don't have to recompose every time after acquiring focus (hopefully accurate focus).  While I'm aware of the challenges these outer focus points presents to manufactures (think Hassleblad etc...), and a post quoting a supposed Canon tech stating that they're really for use with AI Server, is it reasonable to believe that they're not as usable in One Shot AF as the center points?

I've heard from another 1D MK IV user who was experiencing the exact same thing, and my tests between the 1D and 5D (tripod, MLU, cable release) bares this out; the accuracy of the outer points just does not produce consistent nor sharp accurate results with the 1D.  Curious if this is indeed just the way these multi focus point cameras are and the need to default back the to center focus and recompose technique.  Anyone?

[jmwscot]

the accuracy of the outer points just does not produce consistent nor sharp accurate results with the 1D.  Curious if this is indeed just the way these multi focus point cameras are and the need to default back the to center focus and recompose technique.  Anyone?

My 1Ds MkIII is the same although I only notice it with the 70-200 IS L 2.8. The 24-105 is pretty consistent. If I'm taking full or three quarter length shots of people in portrait mode, using the outer focus point is a bit unreliable. Most shots are fine but a few are just slightly out of focus i.e. I've focused on the eyes but the end of the nose is what the camera gives as the sharpest plane. The camera has been back at Canon for all the latest updates and adjustments.

I'm going to go back to centre point in my next job tomorrow but it is very awkward if the point you want to focus on is towards the edge of frame. I was hoping that the forthcoming 1Ds Mk1V would not have this problem.

John

[markjhn]

Bingo!  With the 70-200 IS L 2.8, I find it pretty accurate at the full 200 zoom, but around the 135-170 zoom, it's dicey and my results are similar to yours.  Had the lens check-out with Canon and it was fine; will be getting the camera back from Canon tomorrow (second time) so I'll see what they found and test it further.

[billy]

My 1Ds MkIII is the same although I only notice it with the 70-200 IS L 2.8. The 24-105 is pretty consistent. If I'm taking full or three quarter length shots of people in portrait mode, using the outer focus point is a bit unreliable. Most shots are fine but a few are just slightly out of focus i.e. I've focused on the eyes but the end of the nose is what the camera gives as the sharpest plane. The camera has been back at Canon for all the latest updates and adjustments.

I'm going to go back to centre point in my next job tomorrow but it is very awkward if the point you want to focus on is towards the edge of frame. I was hoping that the forthcoming 1Ds Mk1V would not have this problem.

John

same thing here:

http://luminous-landscape.com/forum/index....60&start=60

[pfigen]

All I know is that I can use any of the manually selected 19 AF points on either of my 1dsMK3's and they're always right on. The MA is dialed on all my af lenses on both bodies and everything from 24L to 200mm1.8 are spot on. There have been a couple of lenses that needed to go to CPS for adjustment as they were inconsistent at different distances, but after adjusting for that, they're all very very good now, and even shooting at 1.2 with the 85 or 1.8 with the 200 I have confidence in the focus accuracy. While the center point is the most accurate, they didn't put the others in there and give you joystick control over them just for laughs. You're supposed to be able to use them and rely on them. If you can't then keep on Canon's case until they fix the problem to your satisfaction.

[Chris L]

All I know is that I can use any of the manually selected 19 AF points on either of my 1dsMK3's and they're always right on. The MA is dialed on all my af lenses on both bodies and everything from 24L to 200mm1.8 are spot on. There have been a couple of lenses that needed to go to CPS for adjustment as they were inconsistent at different distances, but after adjusting for that, they're all very very good now, and even shooting at 1.2 with the 85 or 1.8 with the 200 I have confidence in the focus accuracy. While the center point is the most accurate, they didn't put the others in there and give you joystick control over them just for laughs. You're supposed to be able to use them and rely on them. If you can't then keep on Canon's case until they fix the problem to your satisfaction.

i dont know if your lucky or if thats normal

[Chris L]

Im trying to get a consensus regarding the use of the outer focus points on primarily the Canon 1d MK IV, though would love to hear from Nikon users as well.  Having shot with the 5D while waiting patiently for Canon to upgrade their focusing systems, I put up with it's sluggish shutter lag and long black-out times, along with it's closely centered 9 focus points.  Most anticipated about the MK IV was being able to use the outer focus points rather than using the center and recomposing method which tended to not always suit what I was shooting, as well as producing soft or completely missed shots.

I purchased the 1D MK IV last month and it's been back to Canon for it's second time due to inaccurate focus.  While the reviews of it's AI Server II AF and tracking abilities have been glowing for the most part (there have been reported questions and inconsistencies; read Galbraith among others) I typically don't use it in AI Server, but instead use One Shot AF and it's outer focus points so I don't have to recompose every time after acquiring focus (hopefully accurate focus).  While I'm aware of the challenges these outer focus points presents to manufactures (think Hassleblad etc...), and a post quoting a supposed Canon tech stating that they're really for use with AI Server, is it reasonable to believe that they're not as usable in One Shot AF as the center points?

I've heard from another 1D MK IV user who was experiencing the exact same thing, and my tests between the 1D and 5D (tripod, MLU, cable release) bares this out; the accuracy of the outer points just does not produce consistent nor sharp accurate results with the 1D.  Curious if this is indeed just the way these multi focus point cameras are and the need to default back the to center focus and recompose technique.  Anyone?

I just called canon tech support regarding this again ( 5th call? different answer every time ). I have the 1dsmk3. they basically told me to only use the center AF point when I 'focus and recompose' for accurate autofocus. So I said" does that basically mean I should never use the outer AF points?" they said no, I can definitely use those. so i said " you just told me not to", and they said ....... you get the idea. then I sent them some test shots of a lifestyle scene shot at F5.6, they said"why dont you stop down to F11 so that you can hold focus better? Are you kidding me?

[GiorgioNiro]

I just called canon tech support regarding this again ( 5th call? different answer every time ). I have the 1dsmk3. they basically told me to only use the center AF point when I 'focus and recompose' for accurate autofocus. So I said" does that basically mean I should never use the outer AF points?" they said no, I can definitely use those. so i said " you just told me not to", and they said ....... you get the idea. then I sent them some test shots of a lifestyle scene shot at F5.6, they said"why dont you stop down to F11 so that you can hold focus better? Are you kidding me?

ID MKIII, 200L 1.8  single af point top center Lens micro adjusted for body.

YMMV.

[markjhn]

ID MKIII, 200L 1.8  single af point top center Lens micro adjusted for body.

YMMV.

Lucky you!  My 1D MK IV has come back from factory repair for the second time without much of an improvement in it's focus sharpness.  They said they found that the adjustment for the AF assembly was incorrect (for the second time!?) etc.... and was adjusted, but shooting in a controlled tripod setting against my 5D, the camera is still soft.  It's going back for it's third time and I'm either hoping they fix it or declare it "good as it gets"; at which point I'll consider trying another body or brand.

[semillerimages]

I sent my 50 1.4 in for a repair and adjustment a month or so ago and when I got it back... it was actually sharp at f1.4, which it never was usable in the past at that aperture.

YMMV however and I did send it in through CPS, not sure if that makes a difference in the repair and adjustment quality or not.

Cheers,

*steve

[markjhn]

I sent my 50 1.4 in for a repair and adjustment a month or so ago and when I got it back... it was actually sharp at f1.4, which it never was usable in the past at that aperture.

YMMV however and I did send it in through CPS, not sure if that makes a difference in the repair and adjustment quality or not.

Cheers,

*steve

Spoke with CPS, and they want the lens along with the body.  If I understand them, they can calibrate THAT specific lens across it's entire focusing range to the 1D MKIV, while not affecting it's performance with my 5D, which is tack sharp.  I'm not sure what happened to the days when you purchase a camera and it works across the entire line of lenses, but..... if it comes back able to produce consistently sharp photos, I'll be happy.  Will I have to do this with every lens I purchase?

[markjhn]

Spoke with CPS, and they want the lens along with the body.  If I understand them, they can calibrate THAT specific lens across it's entire focusing range to the 1D MKIV, while not affecting it's performance with my 5D, which is tack sharp.  I'm not sure what happened to the days when you purchase a camera and it works across the entire line of lenses, but..... if it comes back able to produce consistently sharp photos, I'll be happy.  Will I have to do this with every lens I purchase?

Camera and 70-200 2.8L IS back from Canon for the 4 time, and all tests well using both the center and out focus points.  One thing I do notice is with low light and low contrast, the camera/lens at the 70mm setting can be a little dodgy with it's acquired focus; a little inconsistent with it's sharpness/focus, but overall the equipment is working as expected.  Thank goodness!

[GiorgioNiro]

Camera and 70-200 2.8L IS back from Canon for the 4 time, and all tests well using both the center and out focus points.  One thing I do notice is with low light and low contrast, the camera/lens at the 70mm setting can be a little dodgy with it's acquired focus; a little inconsistent with it's sharpness/focus, but overall the equipment is working as expected.  Thank goodness!

Just purely for information, I would like to comment that I have now been using the Canon MK IV for just under 2 months.
The photo below is from a recent session shot at ISO 500 under HMI lighting at 1/500 th sec at F2.5 using the MKIV and a 200L IS. The AF is set for single point (top center) with AF Expansion => Surrounding AF Points. Micro adjustment of the 200L IS was achieved at +1 setting.

The new camera is in my opinion outstanding and the files are even better than the MK III.

Best,
GN

[neil snape]

I have always had this problem with my 5DMKII.

I shoot beauty close up in studio without a tripod. Almost always the 100mm macro.

In tests the outer and top most AF point (handle towards the top) works fine, although in low light it's not very good.

Yet in actual shooting the focus often pulls towards anything closer like an elbow, a shoulder, etc. The red AF point lights when shooting in single shot, so it's behaving as expected, the focus point is either fooled or inconsistent. The centre point does not do this.

I've not found a solution other than go for Nikon> so far I just live with it, and have a frustrating timne when the ideal frame is the one where the focus is short!

I did not have this problem with the 5D.

It is not the type of problem technicians are able to fix either as it is in fast shooting conditions, not under test situations.

[Ben Rubinstein]

My 1Ds mkIII at CPS for the third time, same problem, inconsistent outer AF points. Sigh..