tschopp wrote:
I don't see why this would manifest on the newer cameras unless the newer cameras talk more often with the lens and it catches a change of state that would otherwise go unnoticed, but It would seem the frequency would just be less on older cameras not no problem at all.
Guilty as charged, it happened on my A7III .
tschopp wrote:
I would think Sony could fix this by adding hysteresis to how much aperture change is required to cancel MF magnification. I would think this would be best as a configurable option as it would reduce correct functionality for well behaved lenses.
I think it would be enough just to increase the minimum time required for the aperture change to be registered, so that temporary/oscilating changes in aperture reporting would go unnoticed . I'm not sure if the "encoder" inside the lens is programmable in that regard though... but Sony could do it in the (body) firmware.
So on your a7 III, does it happen once in a blue moon.......or are there times it goes full on ape?
If it's a tolerance thing (signal timing, etc), I could see it happening on older cameras, but maybe infrequently enough to just think it was a fluke. But if it goes crazy to the point where it's tough to use the lens on the a7 III, then I don't have a theory.
j4nu wrote:
Guilty as charged, it happened on my A7III .
I think it would be enough just to increase the minimum time required for the aperture change to be registered, so that temporary/oscilating changes in aperture reporting would go unnoticed . I'm not sure if the "encoder" inside the lens is programmable in that regard though... but Sony could do it in the (body) firmware.
It happened more like you described it in your previous post, once it started it could make magnification nearly unusable (but TBH, I don't remember any more how bad it was compared to A1). It didn't happen often enough for me to consider sending it to service though (e.g. there were days when I picked up the lens for an hour or two and it worked without any issues during that period). Full disclosure, I didn't use CV35/1.4 too often back then and still don't now ... so maybe I just didn't use it enough to notice how regularly the issue occurs (and I don't have that A7III anymore).
tsdevine wrote:
So on your a7 III, does it happen once in a blue moon.......or are there times it goes full on ape?
If it's a tolerance thing (signal timing, etc), I could see it happening on older cameras, but maybe infrequently enough to just think it was a fluke. But if it goes crazy to the point where it's tough to use the lens on the a7 III, then I don't have a theory.
tsdevine wrote:
That's my fear, quite a few 3rd party lenses use the Sony mechanism via the camera, including the Zeiss Batis series. (Which Tamron does as well, so I can't help tying Zeiss Batis to Tamron....but for this conversation, it's meaningless). I'm not aware of any end user upgradable firmware capability for Zeiss Loxia or CV (again...can't help but draw the parallel to the rumor that Cosina makes Loxia lenses for Zeiss.). I would send my lenses in for a firmware update, if that was the only option.
I can see a timing issue if the camera is polling the lens. Maybe it overwhelms the lens and it has trouble responding in the allotted cycle...and the camera reacts poorly to that. Or it may create a jitter scenario, which could explain how it can be really cranky at one point and fairly well behaved at others. If the lens is responsible to report a change, only when a change occurs (not polled by the camera)...then it's harder for me to understand how this is a problem exists only when using newer Sony cameras.
One thing that is interesting, I see the aperture as red I via the EVF when the lens is acting whacko. For example, I don't believe I can release the shutter in timer mode if the lens is acting up.....doesn't matter if I'm in magnified view. Sometimes the aperture shows red and the shutter button works in timer mode, sometimes it doesn't. But it doesn't 100% not work or 100% work. When it's not red it always works.
And sometimes the lens is super cranky and it's hard to find any aperture where you can use magnify. Sometimes the lens is pretty well behaved. Sometimes when it's cranky, if I change from one of my saved modes to another and back again...it gets less cranky. Sometimes turning off the camera and turning it back on makes it seem less cranky. Sometimes it lets me go into magnified view, but as soon as I turn the focus ring it bounces out. Sometimes it bounces out immediately. Sometimes it gives me a second or two, then it bounces out.
My Loxia 25 is pretty consistent: at apertures between f2.8 - f5.6 it will randomly (no reason or rhyme) exit magnified view directly after turning the focus ring and getting into magnified view, literally a spilt second after, and when I then "massage" the focus ring a bit, shifting aperture up and down and exerting mild sideways pressure while doing so, I can always get the lens to behave within a few tries. That is why, even though I live in a neigbouring country to Germany, where the service centre is in Oberkochen, I have decided not to send the lens in.
I have sent in Zeiss lenses in the past, but what put me off, was their ridiculous reponse time over email ( 1-2 months) and their total lack of will to think with me on what is happening here. On their behalf: they did say to send the lens in, but how are they going to fix what they are not even acknowledging? Now that I know Zeiss is (not...) leaving the e-mount lenses arena, it makes more sense, but I am still not going to send the lens is before they tell me what they are going to do to fix it.
Bokehddicted wrote:
Why do you come to the conclusion after your findings that it should be fixed in the lens? It just reports its aperture value.
Its the function in the camera that gets triggered by various inputs that triggers magnification to go off. The logic and threshold should be a function of the implementation of the feature. Not snap our at all. Snap out only after changing 1/3rd of a stop… i personally would not only like to see this fixed, but also to be able to switch this off altogether. Only to snap out by pressing the focus zoom button again.
You could make the argument that you want different functionality with how the magnification is exited. That would certainly be a camera firmware update. I only have a couple manual lenses and they are non chipped, but what I do is assign a button to magnify. That might be a reasonable work around, then you can magnify or not as you see fit. That will work on current cameras, you just won't get auto magnification when you turn focus. Unless the aperture change causes the magnification to drop on this as well. I will see if I can test that.
I'm with you. I have excellent copies of the 21, 25, and 85. I'm not shipping them to Zeiss either, unless I know they know what the fix is. And if it's firmware, I'd be much more inclined to send it in. If they offered to send me another copy, no thanks. Not playing roulette with copy variance. I did pick up a second Loxia 25 new for $679....I would be willing to send that one in I guess, just to see what they do.
Interesting tricks you've found, I need to try that.
ChrisMak wrote:
My Loxia 25 is pretty consistent: at apertures between f2.8 - f5.6 it will randomly (no reason or rhyme) exit magnified view directly after turning the focus ring and getting into magnified view, literally a spilt second after, and when I then "massage" the focus ring a bit, shifting aperture up and down and exerting mild sideways pressure while doing so, I can always get the lens to behave within a few tries. That is why, even though I live in a neigbouring country to Germany, where the service centre is in Oberkochen, I have decided not to send the lens in.
I have sent in Zeiss lenses in the past, but what put me off, was their ridiculous reponse time over email ( 1-2 months) and their total lack of will to think with me on what is happening here. On their behalf: they did say to send the lens in, but how are they going to fix what they are not even acknowledging? Now that I know Zeiss is (not...) leaving the e-mount lenses arena, it makes more sense, but I am still not going to send the lens is before they tell me what they are going to do to fix it. ...Show more →
Below is a link to the document I found about the protocol. Unless the camera thinks the lens has a problem and starts the lens initiation routine again I don't see much that would go wrong with this.
The real way to figure out exactly what is happening is to sniff the communications and see what is happening with the aperture message from the lens while it is misbehaving.
I think it was mentioned in one of the threads on the issue, maybe even this one, but when aperture change is detected, it does not only cause the magnification to drop, but you're unable to take a picture as well (the camera is kinda blocked until aperture change is completed). I've never seen that with my CVs, but somebody reported it with his lenses...
I mentioned above that when in timer mode I often can't initiate the shutter. It very well could be that way outside of timer mode. Will make a mental note to check.
j4nu wrote:
I think it was mentioned in one of the threads on the issue, maybe even this one, but when aperture change is detected, it does not only cause the magnification to drop, but you're unable to take a picture as well (the camera is kinda blocked until aperture change is completed). I've never seen that with my CVs, but somebody reported it with his lenses...
tschopp wrote:
I would think Sony could fix this by adding hysteresis to how much aperture change is required to cancel MF magnification. I would think this would be best as a configurable option as it would reduce correct functionality for well behaved lenses.
I don't have a Loxia, but I would love Sony fixing this. More specifically don't drop out of focus magnification for any changes in aperture or zoom. While they are at it, they could also fix the error occurring when you try to go into focus magnification when AF-C is set (simply use the same cross hair AF as when in AF-S). The way this is currently implemented drives me nuts...
Thanks for posting this. It apparently confirms what I suspected: there is a hardware issue with the aperture ring:
"Dismantled lens to repair iris encoder mechanism"
This hardware failure was never picked up on the older slower bodies, but any body going forward will show the same issue. It may be worth sending the lens to Zeiss after all.
smpetty wrote:
Unless they offer a recall and free repair, they've definitely dropped the ball. Also the repair took three and a half months. Good Lord.
Yes, I should have added "completely" there .
Still better than nothing, which I think I would get from Cosina...
Seems like they are trying to quietly put the ball down and roll it under the bed.
smpetty wrote:
Unless they offer a recall and free repair, they've definitely dropped the ball. Also the repair took three and a half months. Good Lord.
My son has surgery next week, but maybe in October or November I'll try to pursue this with Zeiss US. I have more than 2 years warranty on all my Loxia's except my 21.
tsdevine wrote:
My son has surgery next week, but maybe in October or November I'll try to pursue this with Zeiss US. I have more than 2 years warranty on all my Loxia's except my 21.
Reading this thread and the redit thread completely I stumbled accross a few reappearing issues:
- The problem is reported slightly more frequently on older lenses.
- It is reported more frequently at f-values that people use regularly (f2.8 to f8), peaking at f4 and f5,6.
- Some users report turning the apperture ring back and forth improves (but does not eliminate) the problem.
- Some reports specify that applying Deoxit reduces / eliminates the problem.
- Some camera models (A1) are more sensitive to the issue than others, but it can happen on several bodies.
- Certain body/lens combinations are more prone to the problem than others [possibly both lens and body being borderline in spec but in opposite directions?]
This reminds me of a chronic problem of the Pentax LX camera body: The potentiometer coding the ASA value of the film had to be set after changing to a film of different sensitivity. Since many people rarely changed film sensitivity, this contact tended to corode with time, leading to erratical jumps in perceived film sensitivity over time (and consecutively jumping film over- and underexposure sporadically or when you bumped this wheel). Pentax recommended turning the wheel back and forth from minimum to maximum ISO once or twice a year, a recommendation which people hardly knew or did. The problem was so notorious that Pentax resorted to exchanging the potentiometer every time an LX camera came in for repair, regardless of the reason of the repair request (an anecdote of the former head technician at the European repair facillities for Pentax in Hamburg). Obviously potentiometers were cheap, a reputation to be lost, and quite obviously other times, other service mentalities (service for the LX stopped somewhere around 2005).
I feel that the reported problems here point to a similar issue: To me this sums up as an electrical contact defect either in the lens at the point where the mechanical signal (turning aperture ring) is transformed into an electrical signal, or when this electrical signal is transfered at the mount from the lens to the camera (In addition there is a varying sensitivity to an altered electric signal between different camera bodies).
I am sold on the idea that applying some cleaning/anticorosive lotion on the decisive contacts might improve or repair this problem.
Concerning this, several questions jump to my mind:
1) Which contacts might need attention? The contacts between the lens and the camera? Contacts within the lens that transduce the mechanical signal to an electronic signal? How can I access possible contacts within the lens? I’m not close in dexterity to Aaron in the repair department of lens rentals, nevertheless I’m somewhat bold and I dare to shim my lenses, so with a proper guide I might give it a shot. Who has taken Loxia and Voigtländer lenses apart and might share some experience?
Cncerning Deoxit: What would you use?
- D5 (contains an evaporating solvent, thus it might allow a thinner application after the solvent has evaporated. On the other hand, could solvents damage parts?).
- D100 (appears to be the pure stuff).
- Deoxit Gold (tube). What makes this special?
What would people recommend for the golden contacts between camera and lens?
What for the putative contacts within the lens?
.
. I'm not sure if the "encoder" inside the lens is programmable in that regard though... but Sony could do it in the (body) firmware.