p.4 #1 · Z8 extremely unreliable/inconsistent AF in mildly low light
armd wrote:
So, it's only with flash? Is the camera focusing accurately without flash and do you have focus assist on/off?
I don't think it's only with flash. It's just that the circumstances in which it happens are the circumstances where I am trying to use flash. If I turn the flash off in these situations I still get extremely unreliable focus.
p.4 #2 · Z8 extremely unreliable/inconsistent AF in mildly low light
story_teller wrote:
I can’t negate the fact that if this were true for all Z8’s the internet forums would be on fire with photographers wanting to burn the Z8 at the stake. That’s not happening. That indicates more likely causes such as settings, user habits/misunderstanding of the AF or your specific camera is malfunctioning.
You are doing a reset. I would leave the camera at basic settings except for your auto focus settings. Try that and see if there’s a difference.
If you’re using back button focus, go to Custom Settings -> A2 and see if you have “Release” or “Focus” set. With BBF you need to have it set to “Release” otherwise you’ll try to focus a second time as you push the shutter button and the camera won’t have enough time to establish focus a second time.
Finally, if the other two methods don’t provide relief, consider sending your camera into Nikon to have them check it out.
Hope you get it sorted out. The Z8 is a very capable camera and personally, I’ve not encountered a low light focus issues you’re encountering. I occasionally miss shots, but my keeper rate is much higher. ...Show more →
I did a reset and it really didn't make a difference.
As far as setting A2, you're suggesting release whereas others have suggested focus and others focus+release. Regardless, I tried all of them at the event last night when I found I couldn't reliably get focus on anything when the light dropped and found no difference.
I sort of want to send the camera in, but I can't possibly imagine what could be wrong with a mirrorless camera body to cause these sorts of problems. Regardless, I absolutely need to have it for another thing in a month so I can't risk sending it now. I might look into doing it then.
That said, if you do search around there are quite a few people out there complaining about these problems, some of them in this thread and a few others in the parallel thread I posted on DPReview. I think it's also true a lot of people seem to have already accepted this as a limitation of the system and won't have posted about it when they got their Z8's because they had the same experience with the Z9, as there are even more threads out there about problems with the Z9 in low light, especially subject detection. The threads I read through tended to conclude with people agreeing subject detect can't be used in low light and hoping it changes in the future.
My point is that I think there are in fact a fair number people who have reported this issue.
p.4 #3 · Z8 extremely unreliable/inconsistent AF in mildly low light
bernardl wrote:
I have just come across this thread and am amazed by what I read.
My Z8 and Z9 have been super reliable with subject detection (mostly people) in various levels of light. I shot a session in my studio 2 days ago, I would call it fairly dark. I have 90+% of keepers using 50mm f1.2 S, 85mm f1.2 S and 135mm f1.8 S at f2.8 (results a bit better with the more recent 85mm f1.2 and 135mm f1.8). Selecting the images for the client is a major pain because they are all technically perfect. All with flash, profoto Pro-10 x 2 and 3x Pro-Head+ through XL umbrella, Bron Para 88 and Profoto soft box 4x1, using Profoto trigger. But I get similar results with natural light or more portable Profoto flashes.
I only use AF-C, typically C1/C2 mode with orientation, subject detection on, I use 2 boxes about 2/3 of the width and 1/3 of the height, erratic setting, lowest possible reaction time, often 20 fps raw lossless. My subjects do move... no difference still super sharp on the pupil of the eye. I always get more actual resolution with my Z8/Z9 than with my 150mp Phaseone back on XF because of how accurate the AF is with the Nikons. I have basically stopped using the phaseone for people as a result. Similar experiences with my GFX-100II although the latest firmware and the 45-100mm f4 delivers pretty convincing results and a high keeper rate as long as subject movement is slow.
I do also shoot ballet rehearsals in very low venue light (still and video) and got great results too. I can share these. This one is ISO4000 at f1.2 and 1/800s.
Compared to my a9III I typically get more consistent focusing with the Nikons when shooting wide open.
I have no clue why the OP is having so different results, but I would personality have the camera checked. Something isn't right at all. Perhaps a full reset first may help as well.
I appreciate the response. Posts like this in part discourage me a great deal because they do seem to suggest that what I am seeing is so far removed from the experienced of some others that I don't expect to ever be able to get a resolution.
It is interesting that you report this with 1.2 and 1.8, though. Perhaps the camera needs those sorts of apertures to succeed. I have been using a 2.8 and an f4 during the period when I have been trying to sort this out, but that's because those are the lenses I will need to use for various things.
p.4 #4 · Z8 extremely unreliable/inconsistent AF in mildly low light
SCoombs wrote:
I appreciate the response. Posts like this in part discourage me a great deal because they do seem to suggest that what I am seeing is so far removed from the experienced of some others that I don't expect to ever be able to get a resolution.
It is interesting that you report this with 1.2 and 1.8, though. Perhaps the camera needs those sorts of apertures to succeed. I have been using a 2.8 and an f4 during the period when I have been trying to sort this out, but that's because those are the lenses I will need to use for various things. ...Show more →
I use back button focus and have been shooting a lot of BIF lately with 600mm f6.3pf lens with excellent results with bird subject detection.
NIKON Z 8NIKKOR Z 600mm f/6.3 VR S lens600mmf/6.31/2000s720 ISO+1.3 EV
NIKON Z 8NIKKOR Z 600mm f/6.3 VR S lens600mmf/6.31/2000s800 ISO+1.3 EV
p.4 #5 · Z8 extremely unreliable/inconsistent AF in mildly low light
Laslo Varadi wrote:
I use back button focus and have been shooting a lot of BIF lately with 600mm f6.3pf lens with excellent results with bird subject detection.
The problem under discussion here concerns low light situations.
p.4 #6 · Z8 extremely unreliable/inconsistent AF in mildly low light
SCoombs wrote:
I did a reset and it really didn't make a difference.
As far as setting A2, you're suggesting release whereas others have suggested focus and others focus+release. Regardless, I tried all of them at the event last night when I found I couldn't reliably get focus on anything when the light dropped and found no difference.
I sort of want to send the camera in, but I can't possibly imagine what could be wrong with a mirrorless camera body to cause these sorts of problems. Regardless, I absolutely need to have it for another thing in a month so I can't risk sending it now. I might look into doing it then.
That said, if you do search around there are quite a few people out there complaining about these problems, some of them in this thread and a few others in the parallel thread I posted on DPReview. I think it's also true a lot of people seem to have already accepted this as a limitation of the system and won't have posted about it when they got their Z8's because they had the same experience with the Z9, as there are even more threads out there about problems with the Z9 in low light, especially subject detection. The threads I read through tended to conclude with people agreeing subject detect can't be used in low light and hoping it changes in the future.
My point is that I think there are in fact a fair number people who have reported this issue....Show more →
You must set A2 to “Release” and not “Focus”! There is no “Focus+Release” option on A2 in the Z8. If you select “Focus” you are enabling the 1/2 press AF capability on the shutter button after you’ve already established focus with the AF-On button. The camera doesn’t have sufficient time to acquire a second focus before the image is taken. It’s easy to check. Focus on a subject with the AF-On button and release release the AF-On. That will lock focus. Next 1/2 press the shutter release. If you hear the camera trying to re-focus, that’s your problem.
If possible, I’ll try to get some low light shots in the next few days and report back. Just bought the 50mm f/1.8 S and will try that out at f/1.8. I’ll also use a 105mm f/1.4 G and see if there is any difference.
p.4 #7 · Z8 extremely unreliable/inconsistent AF in mildly low light
SCoombs wrote:
The problem under discussion here concerns low light situations.
You also introduced other factors such as AF-C vs AF-S and Back Button focus in your previous posts on this thread as other potential factors and that is all I was addressing in my post. If that does not apply, feel free to disregard my post. I don’t do much low light shooting or indoor flash. The times I played around with indoor flash for portrait shots, subject detection worked fine and I used AF-C and BBF.
p.4 #8 · Z8 extremely unreliable/inconsistent AF in mildly low light
story_teller wrote:
You must set A2 to “Release” and not “Focus”! There is no “Focus+Release” option on A2 in the Z8. If you select “Focus” you are enabling the 1/2 press AF capability on the shutter button after you’ve already established focus with the AF-On button. The camera doesn’t have sufficient time to acquire a second focus before the image is taken. It’s easy to check. Focus on a subject with the AF-On button and release release the AF-On. That will lock focus. Next 1/2 press the shutter release. If you hear the camera trying to re-focus, that’s your problem.
I see the problem. You're talking about the setting for AF-S, whereas I am not shooting in AF-S but AF-C.
That said, your description of setting a2 is not correct. It has nothing to do with whether or not the camera will attempt to refocus with the shutter button. This is determined by a6 - AF activation. As long as a6 is set to on, the camera will always try to focus when you 1/2 press the shutter. By trying to use BBF and setting a2 to release, all that is happening is that the camera is focusing with BB and then trying to refocus when you press the shutter but, as you say, it doesn't have time to, so if the subject has moved at all since you pressed the AF-ON button the shot will be out of focus.
p.4 #9 · Z8 extremely unreliable/inconsistent AF in mildly low light
Laslo Varadi wrote:
You also introduced other factors such as AF-C vs AF-S and Back Button focus in your previous posts on this thread as other potential factors and that is all I was addressing in my post. If that does not apply, feel free to disregard my post. I don’t do much low light shooting or indoor flash. The times I played around with indoor flash for portrait shots, subject detection worked fine and I used AF-C and BBF.
I mentioned BBF because I suspected that at least part of the problem (though I'd now say only a very small part) may be that when using AF-C the camera would get initial focus and then try to readjust the focus as the AF-ON button is held and lose it in the process, so my theory was that people who do not use BBF may be getting shots taken using only that initial focus acquisition which may be more accurate. I use BBF all the time, including for wildlife, and it works fine.
p.4 #10 · Z8 extremely unreliable/inconsistent AF in mildly low light
@SCoombs - I have my camera in AF-C, but when I release the AF-On button, it acts like AF-S and focus is locked. I can’t stress this enough, if you can refocus using the 1/2 press on the shutter, your camera is not set up correctly.
A6-AF Activation deals with the AF-On button, A2 deals with the shutter release button. You need to set both correctly. This is a common problem with people complaining about Nikon cameras not focusing correctly, not just the Z8. A2 is primarily about shooting in AF-S, but also applies to AF-C. If I hold the AF-On button continuously (in AF-C mode) I can use the shutter release multiple times without fear of double focusing while I’m shooting.
p.4 #11 · Z8 extremely unreliable/inconsistent AF in mildly low light
SCoombs wrote:
I don't think it's only with flash. It's just that the circumstances in which it happens are the circumstances where I am trying to use flash. If I turn the flash off in these situations I still get extremely unreliable focus.
By the way, are you talking about the focus assist on the flash or a setting on the camera?
p.4 #12 · Z8 extremely unreliable/inconsistent AF in mildly low light
story_teller wrote:
@SCoombs@ - I have my camera in AF-C, but when I release the AF-On button, it acts like AF-S and focus is locked. I can’t stress this enough, if you can refocus using the 1/2 press on the shutter, your camera is not set up correctly.
A6-AF Activation deals with the AF-On button, A2 deals with the shutter release button. You need to set both correctly. This is a common problem with people complaining about Nikon cameras not focusing correctly, not just the Z8. A2 is primarily about shooting in AF-S, but also applies to AF-C. If I hold the AF-On button continuously (in AF-C mode) I can use the shutter release multiple times without fear of double focusing while I’m shooting. ...Show more →
This is simply incorrect. a2 will have no effect at all when in AF-C mode. The a6 setting is the only one which affects the camera trying to refocus with the shutter release button.
In fact this wouldn't even make any sense. The whole point of AF-C is that the camera will constantly adjust refocus as the focus changes due to the subject or camera moving. If there were some setting that locked focus while in AF-ON was being held, then AF-C wouldn't actually be doing the function which is the entire purpose of AF-C.
And just in case you're not convinced, I have a2 set to focus and a6 set to AF-ON only and the camera does not focus when pressing the shutter halfway, because setting a6 to AF-ON only is the only setting that determines whether the shutter button can activate focusing.
p.4 #13 · Z8 extremely unreliable/inconsistent AF in mildly low light
SCoombs wrote:
This is simply incorrect. a2 will have no effect at all when in AF-C mode. The a6 setting is the only one which affects the camera trying to refocus with the shutter release button.
In fact this wouldn't even make any sense. The whole point of AF-C is that the camera will constantly adjust refocus as the focus changes due to the subject or camera moving. If there were some setting that locked focus while in AF-ON was being held, then AF-C wouldn't actually be doing the function which is the entire purpose of AF-C.
And just in case you're not convinced, I have a2 set to focus and a6 set to AF-ON only and the camera does not focus when pressing the shutter halfway, because setting a6 to AF-ON only is the only setting that determines whether the shutter button can activate focusing. ...Show more →
p.4 #14 · Z8 extremely unreliable/inconsistent AF in mildly low light
I just tried it out and you are 100% correct. it no longer matters. I’ve been so used to doing that with some of the earlier Nikon DSLRs that I automatically applied it to mirrorless without thinking. Lesson learned. The Z6 is the same as well.
I’ll still try to get some low light people photos in the next few days and see what the keeper rate is. Any specific apertures or tests you want to see?
p.4 #15 · Z8 extremely unreliable/inconsistent AF in mildly low light
As of yet, I do not photograph humans in-close, where I would even notice an eye slightly out of focus. In the future maybe but not now.
Still, I just want to add to SCoombs last post regarding AF-ON.
Last year I decided to stick with BBAF (AF-ON). It absolutely prevents the shutter button from focusing. This allows me to capture focus and not be annoyed by that shutter button refocusing.
And I only have to press and release the AF-ON to lock that focus. You do not have to hold the AF-ON button with the Z8. I also have the f2 button exclusively for the Single AF square. And my f1 button magnifies the field that I see in the EVF allowing me to critically focus.
p.4 #17 · Z8 extremely unreliable/inconsistent AF in mildly low light
story_teller wrote:
I just tried it out and you are 100% correct. it no longer matters. I’ve been so used to doing that with some of the earlier Nikon DSLRs that I automatically applied it to mirrorless without thinking. Lesson learned. The Z6 is the same as well.
I’ll still try to get some low light people photos in the next few days and see what the keeper rate is. Any specific apertures or tests you want to see?
I appreciate the offer. I am currently working through the photos from my event last night and will post some examples later today of successes and failures and that might offer some direction as to what comparisons may be helpful.
p.4 #18 · Z8 extremely unreliable/inconsistent AF in mildly low light
sjms wrote:
i'm trying to figure out why one is using a flash to begin with. if so, what flash is being used.
Why using flash? Because the lighting of the setting for a particular photograph calls for it. In particular flash (and by flash I mean a speedlight) is typically used for many or most indoor and/or evening/nighttime events. The speedlight I have been using is a Sunpak DF4000u - by no means a high end model and I will likely be replacing it soon, but it's been perfectly adequate to this point and in any case the focusing happens long before the flash is fired.
p.4 #19 · Z8 extremely unreliable/inconsistent AF in mildly low light
there is one of your issues. is it a flash that will work properly with the Z models? the ability to sync properly is even limited to a small grouping of nikon speedlights. the SB700, SB5000. in addition, there are a few Nissin models and profoto possibly the newr Godox profoto look alike too.
p.4 #20 · Z8 extremely unreliable/inconsistent AF in mildly low light
sjms wrote:
there is one of your issues. is it a flash that will work properly with the Z models? the ability to sync properly is even limited to a small grouping of nikon speedlights. the SB700, SB5000. in addition, there are a few Nissin models too.
It produces banding for high speed sync (along with apparently all but a handful of Profoto models) but otherwise it works fine. So long as focus is acquired, the photo will look fine with good flash exposure. It properly interfaces to report aperture and focal length and does everything properly.
And again, the flash has nothing to do with the focus.
