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Archive 2021Strange AF pumping on 35 GM 1.4 and A7R4
p.1 #1Strange AF pumping on 35 GM 1.4 and A7R4
I'm in AF-C here - and pretty low-light.
Whenever it has some difficulties focussing it starts pumping in a frequency of about 5Hz. Very strange and annoying.
Is there any hope sony will fix this with an update? Or am I missing something?
https://imgur.com/a/qlmghRU
Whenever it has some difficulties focussing it starts pumping in a frequency of about 5Hz. Very strange and annoying.
Is there any hope sony will fix this with an update? Or am I missing something?
https://imgur.com/a/qlmghRU
Mar 23, 2021 at 12:07 PM
p.1 #2Strange AF pumping on 35 GM 1.4 and A7R4
obwohl wrote:
I'm in AF-C here - and pretty low-light.
Whenever it has some difficulties focussing it starts pumping in a frequency of about 5Hz. Very strange and annoying.
Is there any hope sony will fix this with an update? Or am I missing something?
https://imgur.com/a/qlmghRU
It looks like the capturing device is pumping, not the f1.4 with A7riv.
I have the combo right before me, but there is no pumping. Doesn't look proper, imo.
I'm in AF-C here - and pretty low-light.
Whenever it has some difficulties focussing it starts pumping in a frequency of about 5Hz. Very strange and annoying.
Is there any hope sony will fix this with an update? Or am I missing something?
https://imgur.com/a/qlmghRU
It looks like the capturing device is pumping, not the f1.4 with A7riv.
I have the combo right before me, but there is no pumping. Doesn't look proper, imo.
Mar 23, 2021 at 12:13 PM
p.1 #3Strange AF pumping on 35 GM 1.4 and A7R4
Hmm, looks pretty bad - maybe a bad copy?
Do you have any similar lens to compare to in the same conditions?
24GM also has a tendency to pump when it's closed down beyond around f6.3...
The solution is to switch to AF-S then.
... but I agree with Holger, the screen wouldn't move if it was the lens that was doing the pumping :| ...
Do you have any similar lens to compare to in the same conditions?
24GM also has a tendency to pump when it's closed down beyond around f6.3...
The solution is to switch to AF-S then.
... but I agree with Holger, the screen wouldn't move if it was the lens that was doing the pumping :| ...
Mar 23, 2021 at 12:18 PM
p.1 #4Strange AF pumping on 35 GM 1.4 and A7R4
just switch to single point focus in low light
Mar 23, 2021 at 12:22 PM
p.1 #5Strange AF pumping on 35 GM 1.4 and A7R4
The device (S20+) has its own problems here, true. But I don't know how to show the problem properly.
The strange thing is: The focus indicator of the Camera is green ->focus is there. But it keeps searching for sth.
AF-S would not pump, when it has focus, true. But as far as I know, AF-S only uses contrast AF instead of phase-AF and thus is much slower. For example when I was trying to focus in normal daylight on clouds, AF-S didn't have any chance while AF-C was very fast and didn't have any problems.
The strange thing is: The focus indicator of the Camera is green ->focus is there. But it keeps searching for sth.
AF-S would not pump, when it has focus, true. But as far as I know, AF-S only uses contrast AF instead of phase-AF and thus is much slower. For example when I was trying to focus in normal daylight on clouds, AF-S didn't have any chance while AF-C was very fast and didn't have any problems.
Mar 23, 2021 at 12:26 PM
p.1 #6Strange AF pumping on 35 GM 1.4 and A7R4
It's the capture device that is pumping, as Holger point out, not the A7r4 or the 35mm lens.
Mar 23, 2021 at 12:29 PM
p.1 #7Strange AF pumping on 35 GM 1.4 and A7R4
obwohl wrote:
I'm in AF-C here - and pretty low-light.
Whenever it has some difficulties focussing it starts pumping in a frequency of about 5Hz. Very strange and annoying.
Is there any hope sony will fix this with an update? Or am I missing something?
https://imgur.com/a/qlmghRU
I can replicate the same AF pumping with other lenses when light is very low and not a lot of contrast between the subject and the back ground. I see your ISO setting is high and very low shutter speed.
Try a target with some contrast between the subject and background and definitely beyond minimum focus distance of the lens in better light.
I'm in AF-C here - and pretty low-light.
Whenever it has some difficulties focussing it starts pumping in a frequency of about 5Hz. Very strange and annoying.
Is there any hope sony will fix this with an update? Or am I missing something?
https://imgur.com/a/qlmghRU
I can replicate the same AF pumping with other lenses when light is very low and not a lot of contrast between the subject and the back ground. I see your ISO setting is high and very low shutter speed.
Try a target with some contrast between the subject and background and definitely beyond minimum focus distance of the lens in better light.
Mar 23, 2021 at 12:30 PM
p.1 #8Strange AF pumping on 35 GM 1.4 and A7R4
Sorry, but that is only half true. Maybe the phone is pumping as well, but there is no doubt the GM 35 is pumping on my Sony. I can hear it and see it and am not making this up here.
Mar 23, 2021 at 12:32 PM
p.1 #9Strange AF pumping on 35 GM 1.4 and A7R4
obwohl wrote:
Sorry, but that is only half true. Maybe the phone is pumping as well, but there is no doubt the GM 35 is pumping on my Sony. I can hear it and see it and am not making this up here.
Well, if you want to be sure, exchange it for another copy...
Sorry, but that is only half true. Maybe the phone is pumping as well, but there is no doubt the GM 35 is pumping on my Sony. I can hear it and see it and am not making this up here.
Well, if you want to be sure, exchange it for another copy...
Mar 23, 2021 at 12:34 PM
p.1 #10Strange AF pumping on 35 GM 1.4 and A7R4
obwohl wrote:
Sorry, but that is only half true. Maybe the phone is pumping as well, but there is no doubt the GM 35 is pumping on my Sony. I can hear it and see it and am not making this up here.
This is easy for me to replicate with other perfectly fine lenses too. I believe you. Try my suggestions. See if that helps.
Sorry, but that is only half true. Maybe the phone is pumping as well, but there is no doubt the GM 35 is pumping on my Sony. I can hear it and see it and am not making this up here.
This is easy for me to replicate with other perfectly fine lenses too. I believe you. Try my suggestions. See if that helps.
Mar 23, 2021 at 12:35 PM
p.1 #11Strange AF pumping on 35 GM 1.4 and A7R4
obwohl wrote:
Sorry, but that is only half true. Maybe the phone is pumping as well, but there is no doubt the GM 35 is pumping on my Sony. I can hear it and see it and am not making this up here.
There is a limit to AF sensitivity. The A7riv is less sensitive than the A9, for example and pumping happens sometimes in very low light (occasionally at weddings in super dark locations, at 1-2 stops earlier with the A7riv than A9ii). In that case increase the flexible spot to medium or large and use contrasty subjects.
The A1 now has -4ev sensitivity, which helps a lot.
Sorry, but that is only half true. Maybe the phone is pumping as well, but there is no doubt the GM 35 is pumping on my Sony. I can hear it and see it and am not making this up here.
There is a limit to AF sensitivity. The A7riv is less sensitive than the A9, for example and pumping happens sometimes in very low light (occasionally at weddings in super dark locations, at 1-2 stops earlier with the A7riv than A9ii). In that case increase the flexible spot to medium or large and use contrasty subjects.
The A1 now has -4ev sensitivity, which helps a lot.
Mar 23, 2021 at 12:41 PM
p.1 #12Strange AF pumping on 35 GM 1.4 and A7R4
OK, thanks for your insight.
One more question: Is contrast AF (i.e. AF-S) generally more precise than phase AF (i.e. AF-C)?
I heard that once but am not sure if this is still true for modern Sonys with modern lenses.
One more question: Is contrast AF (i.e. AF-S) generally more precise than phase AF (i.e. AF-C)?
I heard that once but am not sure if this is still true for modern Sonys with modern lenses.
Mar 23, 2021 at 12:48 PM
p.1 #13Strange AF pumping on 35 GM 1.4 and A7R4
obwohl wrote:
OK, thanks for your insight.
One more question: Is contrast AF (i.e. AF-S) generally more precise than phase AF (i.e. AF-C)?
I heard that once but am not sure if this is still true for modern Sonys with modern lenses.
I mostly use AF-C and rarely (2s delay) AF-S. I don't need AF-S for my type of shooting.
OK, thanks for your insight.
One more question: Is contrast AF (i.e. AF-S) generally more precise than phase AF (i.e. AF-C)?
I heard that once but am not sure if this is still true for modern Sonys with modern lenses.
I mostly use AF-C and rarely (2s delay) AF-S. I don't need AF-S for my type of shooting.
Mar 23, 2021 at 01:32 PM
p.1 #14Strange AF pumping on 35 GM 1.4 and A7R4
I'd even venture to say that if you've bought into the Sony ecosystem to use AF-S, you don't really know what you're doing 
... Of course, there are exceptions but still...
... Of course, there are exceptions but still...Mar 23, 2021 at 01:49 PM
p.1 #15Strange AF pumping on 35 GM 1.4 and A7R4
Could you explain that? I certainly want to learn from you 
Mar 23, 2021 at 02:25 PM
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p.1 #16Strange AF pumping on 35 GM 1.4 and A7R4
obwohl wrote:
I'm in AF-C here - and pretty low-light.
Whenever it has some difficulties focussing it starts pumping in a frequency of about 5Hz. Very strange and annoying.
Is there any hope sony will fix this with an update? Or am I missing something?
your video appears to show you trying to focus on your own knee??
as was mentioned earlier, don't try to use af near the mfd of a lens, which in this case would be: "Minimum Focus Distance - 9.8" / 25 cm", according to the b&h page: https://www.bhphotovideo.com/c/product/1613424-REG/sony_fe35f14gm_fe_35mm_f_1_4_gm.html/specs
I'm in AF-C here - and pretty low-light.
Whenever it has some difficulties focussing it starts pumping in a frequency of about 5Hz. Very strange and annoying.
Is there any hope sony will fix this with an update? Or am I missing something?
your video appears to show you trying to focus on your own knee??
as was mentioned earlier, don't try to use af near the mfd of a lens, which in this case would be: "Minimum Focus Distance - 9.8" / 25 cm", according to the b&h page: https://www.bhphotovideo.com/c/product/1613424-REG/sony_fe35f14gm_fe_35mm_f_1_4_gm.html/specs
Mar 23, 2021 at 02:38 PM
p.1 #17Strange AF pumping on 35 GM 1.4 and A7R4
obwohl wrote:
Could you explain that? I certainly want to learn from you
Well, think about it - I'm sure you tried to shooting in AF-S and AF-C so you know how they work.
If a hypothetical typical user looking to buy into a mirrorless system does not care for responsive AF, then other factors take precedence...
Could you explain that? I certainly want to learn from you
Well, think about it - I'm sure you tried to shooting in AF-S and AF-C so you know how they work.
If a hypothetical typical user looking to buy into a mirrorless system does not care for responsive AF, then other factors take precedence...
Mar 23, 2021 at 04:00 PM
p.1 #18Strange AF pumping on 35 GM 1.4 and A7R4
You are at ISO 8000, 1/25 of a second at f/1.4. That is -0.67EV, and you aren't exposed correctly for your knee, you are exposed correctly for the wall.
My guess is that the majority of your knee is somewhere around -3EV which is pushing the limit of the A7r IV autofocusing capabilities.
My guess is that the majority of your knee is somewhere around -3EV which is pushing the limit of the A7r IV autofocusing capabilities.
Mar 23, 2021 at 04:33 PM
p.1 #19Strange AF pumping on 35 GM 1.4 and A7R4
Common.
The camera cannot lock focus.
Find a vertical line to focus on and it will lock.
The camera cannot lock focus.
Find a vertical line to focus on and it will lock.
Mar 24, 2021 at 05:24 AM
p.1 #20Strange AF pumping on 35 GM 1.4 and A7R4
I'm not complaining about focus problems, I am complaining about focus indicator being green (i.e. focus found) and fast pumping going on.
Mar 24, 2021 at 05:35 AM