Too bad. I am actually a Canon shooter who has bought a Nikon D800 and SB-910 and immediately experienced the same focus issue as reported here. I'm quite dissatisfied with my 5d3's AF performance in low light (sluggish and with frequent front focusing using AF assist), so I am looking into Nikon. My last Canon resort is to purchase one 600EX-RT and see if it resolves the sluggish/inaccurate low light AF of the 5d3 using 580EX focus assist. If that doesn't work, then I have no choice but to either stick with my 5d2s (which are fast in low light but have poorer high ISO performance and outer points for general use) or try Nikon more seriously.
form wrote:
Too bad. I am actually a Canon shooter who has bought a Nikon D800 and SB-910 and immediately experienced the same focus issue as reported here. I'm quite dissatisfied with my 5d3's AF performance in low light (sluggish and with frequent front focusing using AF assist), so I am looking into Nikon. My last Canon resort is to purchase one 600EX-RT and see if it resolves the sluggish/inaccurate low light AF of the 5d3 using 580EX focus assist. If that doesn't work, then I have no choice but to either stick with my 5d2s (which are fast in low light but have poorer high ISO performance and outer points for general use) or try Nikon more seriously....Show more →
So wait, you never tried the 600EX-RT on the 5D III, which has a focus assist light specifically designed for the 5D III and 1D X AF system, and instead you've invested a load of cash into Nikon gear?!?
I'm perplexed. Just a photographer and not as technically knowledgeable as most of you. I shoot with D7100 and D800e and have 12 SB-910 speedlights which have never caused me this kind of problem you list here. In fact I often go into an operating room with three separate three light set ups and shoot off pocket wizards. That's nine lights I'm being paid to use with never a back or front focus issue using macro lenses. I'm not understanding the problem.
I'm perplexed. Just a photographer and not as technically knowledgeable as most of you. I shoot with D7100 and D800e and have 12 SB-910 speedlights which have never caused me this kind of problem you list here. In fact I often go into an operating room with three separate three light set ups and shoot off pocket wizards. That's nine lights I'm being paid to use with never a back or front focus issue using macro lenses. I'm not understanding the problem.
First, not everyone has the issue. Second, not everyone has the issue with the same combination - some people have it with different combinations, e.g. D800 may have focus issues with SB800 but not SB910, or one person's D800 works with the SB910 while another's does not, or someone has a D800 and D700 and the D700 focuses fine with the flash focus assist while the D800 does not.
Third, this is something related to having the flash on-camera or having the AF assist lamp on the flash activate. If the flash's AF assist lamp does not activate, the focus "adjustment" does not occur.
johnctharp wrote:
So wait, you never tried the 600EX-RT on the 5D III, which has a focus assist light specifically designed for the 5D III and 1D X AF system, and instead you've invested a load of cash into Nikon gear?!?
I've had a D800 for a while, but I bought an SB910 recently so I could use the D800 at receptions. I will likely be trying the 600EX-RT on the 5d3 to see if it resolves part of the issue, but there is another part it will never resolve: The issue where, in mid-level lighting which the 5d2 focuses quickly in without any AF assist need, the 5d3 pauses and hesitates and delays. I have sent in my 5d3 to Canon and have followed their instructions for how to set the AF points, but the result is the same.
I have also experience the exact same focus shifting when using the AF assist on the SB-910. I turned it off. Luckily for me, I rarely use flash, but I can definitely feel your pain.
P.S. Didin't realize this was a really old thread. Also the 85mm F1.8g was probably the most inconsistent af'ing lens I have owned from Nikon. Maybe I just had a bad copy.
I have been following this issue for a few years both here and DPReview. Never saw anyone saying they have the problem with the SB800.
All the cameras I have owned with this issue (about 3 over time) never behaves like this with the 2 SB800 I own. Only with SB900 and SB700. Never owned a SB910.
unclemikey wrote:
I'm perplexed. Just a photographer and not as technically knowledgeable as most of you. I shoot with D7100 and D800e and have 12 SB-910 speedlights which have never caused me this kind of problem you list here. In fact I often go into an operating room with three separate three light set ups and shoot off pocket wizards. That's nine lights I'm being paid to use with never a back or front focus issue using macro lenses. I'm not understanding the problem.
This is my experience exactly. I shoot 4 SB-910's and 1 SB-900 every week, and the focus assist beam is superb coming from my SB-910 on both my D700 and D800, regardless of lens selection. There always comes a point where it's too dark at the wedding reception to use AF-C and that's when AF-S with focus assist saves my bacon
If that's not your experience, and focus assist is failing you, wow, that would be awful. I'd be lost without it
form wrote:
Because the issue still exists, persists, and has not been acknowledged, nor is there a solution - merely non-ideal workarounds.
The issue still exist and you started a good thread on it a little while ago. The OP of this thread has moved on to Canon over a year ago. Throwing old threads back up doesn't move the ball forward. Better to keep the discussion within a single thread. Just my opinion.
Don't know if it will help or not but I recently bought a Phottix Mitros + flash for my Nikons. I have only shot one wedding with it on a D3s, but it seems to work fine. But,then again, I never noticed any problems with the 910 or the 900. I leave the camera on afc using back button focus.
This wedding reception wasn't real dark, so it might not have been a good test. But i really like the flash and its built in odin system, which I have already had. The radio triggers are fantastic.
James R wrote:
The issue still exist and you started a good thread on it a little while ago. The OP of this thread has moved on to Canon over a year ago. Throwing old threads back up doesn't move the ball forward. Better to keep the discussion within a single thread. Just my opinion.
I've found that l can get different results when microfocus adjusting my fast lenses depending on color temperature. For whatever reason, color temperature can have a pretty dramatic effect on microfocus adjustment. Look at the 85 1.2 graph in this article:
It could simply be that the red focus assist lamp is throwing off a lens that's focus was calibrated at a different color temperature. You could take some test shots with a red flashlight for focus assist and see if you get the same results. That would tell you whether something in the Nikon firmware was causing it, or some property of the lens like local CA.
It would also be interesting for someone with Canon gear to try the same test with an 85 1.2 or 1.8.
I've found that l can get different results when microfocus adjusting my fast lenses depending on color temperature. For whatever reason, color temperature can have a pretty dramatic effect on microfocus adjustment. Look at the 85 1.2 graph in this article:
It could simply be that the red focus assist lamp is throwing off a lens that's focus was calibrated at a different color temperature. You could take some test shots with a red flashlight for focus assist and see if you get the same results. That would tell you whether something in the Nikon firmware was causing it, or some property of the lens like local CA.
It would also be interesting for someone with Canon gear to try the same test with an 85 1.2 or 1.8. ...Show more →
Yes, for reasons described here and more completely, here.
