The Amazing Sony A1/A7/A9/APS-C & Anything else welcome Mega Thread!

nandbytes said:
He assumes a lot of things based on his misconceptions
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As I said before. I am wondering why Sony doesn't admit there is a qc issue with the lens because other recent lenses has been recalled. So it's not as if Sony are scared to admit there is a bad batch of lenses?
 
twist said:
For those that didn't think a mirrorless camera and lens can front or back focus like I found with the Samyang 35mm 1.4. Heres the Tamron 28-75 doing it.

http://www.fredmiranda.com/forum/topic/1531582/29#lastmessage
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@twist did you adjust your samyang using the in camera adjustments or with the dock? Mine does not allow me to adjust the af fine tuning if i click on that option in the a7iii's menu. Not that i have thought/ tested it enough to see if it needs it. but following your experience was wondering at looking in to it as there is no harm in seeing.

Thanks
 
jonneymendoza said:
So assumption not fact?
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FACT, its the way the lens is constructed, dont you know how to look for a teardown?

FACT, There are hundreds of reports of this lens being decentered. FACT, the front element cant be changed without replacing the entire front group, FACT, they use shims to adjust and correct the optics.
 
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nandbytes said:
He assumes a lot of things based on his misconceptions
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You are the one making assumptions without even doing any research. The lens has widely reported QC issues and if its not by poor design then what is the issue?

Perhaps its all the beginner photographers spending upwards of £1.3k on a new lens that dont know how to use it eh, it just so happens that all their shots are always softer on one side :LOL:
 
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RPhotos said:
@twist did you adjust your samyang using the in camera adjustments or with the dock? Mine does not allow me to adjust the af fine tuning if i click on that option in the a7iii's menu. Not that i have thought/ tested it enough to see if it needs it. but following your experience was wondering at looking in to it as there is no harm in seeing.

Thanks
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The in camera adjust won't work mate, you need the dock because the values are for the lens, not camera.
 
twist said:
FACT, its the way the lens is constructed, dont you know how to look for a teardown?

FACT, There are hundreds of reports of this lens being decentered. FACT, the front element cant be changed without replacing the entire front group, FACT, they use shims to adjust and correct the optics.
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twist said:
FACT, its the way the lens is constructed, dont you know how to look for a teardown?

FACT, There are hundreds of reports of this lens being decentered. FACT, the front element cant be changed without replacing the entire front group, FACT, they use shims to adjust and correct the optics.
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Yes i can look at a teardown but unless i know exactly how a lens is contructed and how everything works together and how i myself could construct such a lens with the right tools and enviornment then i can comment with viable facts to backup any claim i have.

So i assume you yourself are the above and can construct a lens such as things and know it was constructed, what tools where used etc etc But you have not further explained exactly why it deCenteres and what specific construction was carried out that highlights this issue and how its replicated.

Is there around 100 reports of this? Do you have at least amazon or similar factual document containing the amount of returns of this item equal to or exceeding the 100's you specified?

And can you send us a link specifically saying that you have to change the whole element to fix it?

What is Shims?

Anyways i am not saying this lens is faultness! Dont forget i asked how i can check for issues with it and with the lieks of amazon i can just return it a couple of times until i have a good copy.

A good copy as you yourself says is epic.
 
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twist said:
For those that didn't think a mirrorless camera and lens can front or back focus like I found with the Samyang 35mm 1.4. Heres the Tamron 28-75 doing it.

http://www.fredmiranda.com/forum/topic/1531582/29#lastmessage
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Calvin's also proven this too with the 85mm. Wilkinsons have now replaced his A7iii but this is also front focussing with the Sony 85mm so it's not looking more likely that it's the lens that's causing the issue rather than the camera as it would be unlikely to have two lemon cameras.
 
snerkler said:
Calvin's also proven this too with the 85mm. Wilkinsons have now replaced his A7iii but this is also front focussing with the Sony 85mm so it's not looking more likely that it's the lens that's causing the issue rather than the camera as it would be unlikely to have two lemon cameras.
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Yeah I would say it’s the lens.
Back / Front focusing on a mirrorless body is a rarity, more likely a lens defect.
 
snerkler said:
Calvin's also proven this too with the 85mm. Wilkinsons have now replaced his A7iii but this is also front focussing with the Sony 85mm so it's not looking more likely that it's the lens that's causing the issue rather than the camera as it would be unlikely to have two lemon cameras.
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Yeah, when he told me I thought it was lens.
 
jonneymendoza said:
Yes i can look at a teardown but unless i know exactly how a lens is contructed and how everything works together and how i myself could construct such a lens with the right tools and enviornment then i can comment with viable facts to backup any claim i have.

So i assume you yourself are the above and can construct a lens such as things and know it was constructed, what tools where used etc etc But you have not further explained exactly why it deCenteres and what specific construction was carried out that highlights this issue and how its replicated.

Is there around 100 reports of this? Do you have at least amazon or similar factual document containing the amount of returns of this item equal to or exceeding the 100's you specified?

And can you send us a link specifically saying that you have to change the whole element to fix it?

What is Shims?

Anyways i am not saying this lens is faultness! Dont forget i asked how i can check for issues with it and with the lieks of amazon i can just return it a couple of times until i have a good copy.

A good copy as you yourself says is epic.
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Like I said look online the information is there, Im not here to spoon-feed you, you didn't even know how to test for decentering which means you have done 0 research into this. Ive actually owned this lens and spent a day testing it hoping to find it wasn't soft on one side... my experience was the same as tons of other people online.
 
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I do seem to be noticing a lot of moire in my photos, it's fairly subtle but it's often there.

Coming from a camera without any AA filter I expected to see less not more.
 
Riz_Guru said:
Yeah I would say it’s the lens.
Back / Front focusing on a mirrorless body is a rarity, more likely a lens defect.
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twist said:
Yeah, when he told me I thought it was lens.
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How can a lens cause front focus? Surely the camera is responsible for focus duties (as I used to be when manual focusing)? The lens focus mechanism will be driven by the camera based on the results it is seeing from its focus system. Which in the case of mirrorless is the sensor. The camera decides it has hit focus, and provides a focus lock confirmation to the user. It is this process that is breaking down, maybe a firmware update required somewhere to improve either communication between lens and body or to update the AF algorithm? I'm just a layman, so see it in those terms :D
 
jj_glos said:
How can a lens cause front focus? Surely the camera is responsible for focus duties (as I used to be when manual focusing)? The lens focus mechanism will be driven by the camera based on the results it is seeing from its focus system. Which in the case of mirrorless is the sensor. The camera decides it has hit focus, and provides a focus lock confirmation to the user. It is this process that is breaking down, maybe a firmware update required somewhere to improve either communication between lens and body or to update the AF algorithm? I'm just a layman, so see it in those terms :D
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Phase detect AF is very complex and is not just a case of bringing two images together, distance, movement and other things are all measured and fed into the processor. I don’t profess to understand it completely but I would guess any miscommunication along the way can cause focus errors.
 
Thread need more pics

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snerkler said:
Phase detect AF is very complex and is not just a case of bringing two images together, distance, movement and other things are all measured and fed into the processor. I don’t profess to understand it completely but I would guess any miscommunication along the way can cause focus errors.
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Yeah I agree, but seeing as the lens is basically sending light and an image optically, it is the camera that is deciding if things are in focus or not.

Communication comes into its own when you are talking about things going back and forward to get the image into focus, and poor communication there is going to make the process difficult especially in C-AF/tracking situations. When it is single point AF surely things are much simpler? Poor communication could cause AF hunting, but to be out of focus? I'm not convinced as it's the camera that gives the green light?

All this technical jiggery pokery is just doing the same as me using manual focus. I move the focus one way, oops too far, I move it the other, oops too far again, I move back again slower, then back again, then 'green light' eventually! At no point in this process is the lens deciding if it's in focus or not.
 
jj_glos said:
Yeah I agree, but seeing as the lens is basically sending light and an image optically, it is the camera that is deciding if things are in focus or not.

Communication comes into its own when you are talking about things going back and forward to get the image into focus, and poor communication there is going to make the process difficult especially in C-AF/tracking situations. When it is single point AF surely things are much simpler? Poor communication could cause AF hunting, but to be out of focus? I'm not convinced as it's the camera that gives the green light?

All this technical jiggery pokery is just doing the same as me using manual focus. I move the focus one way, oops too far, I move it the other, oops too far again, I move back again slower, then back again, then 'green light' eventually! At no point in this process is the lens deciding if it's in focus or not.
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You're wrong, because the dock is making the adjustments to the AF of the lens... It was night and day with the Samyang and dock adjustments... not once were the camera settings changed.
 
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jj_glos said:
No I'm not, you're adding a compensation to your lens due to the camera system not identifying the correct in focus target.
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I misinterpreted your post then, yes, the lens requires the compensation to match what the camera sees as in focus.
 
F/1.4 said:
Raymond how are you finding the Sony system ? I can't wait to get these 3 art lenses. Miss the 1.4 I had before !
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I wouldn’t call it a system as I’ve only have 1 body 1 lens and no flash. The camera is great, has its quirks, some I can work around, some can’t but I’m loving it. It’s probably the best camera I’ve ever had, even taking into account the time vs tech at the time of purchase.
 
jj_glos said:
No I'm not, you're adding a compensation to your lens due to the camera system not identifying the correct in focus target.

The lens doesn't decide focus, the camera does.
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I don't know the answer for sure but I would say it has to be the camera/lens combo and the communication between the two, otherwise if you had a specific camera that front focussed on one lens by your rationale then all lenses would front focus would they not? The fact that different lenses show different front/back focus issues on the same camera suggest to me that the lens does play a part (somehow) to the final focus.
 
snerkler said:
I don't know the answer for sure but I would say it has to be the camera/lens combo and the communication between the two, otherwise if you had a specific camera that front focussed on one lens by your rationale then all lenses would front focus would they not? The fact that different lenses show different front/back focus issues on the same camera suggest to me that the lens does play a part (somehow) to the final focus.
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This is what I am trying to understand, whether it is my gammy eye or the camera CPU, ultimately you are looking at the image to determine if it is in focus. When it is, you give the green light. On Fuji I have never seen any problems, on Canon I have spent many an hour getting to know MFA (easier now with FoCal).

On a DSLR with mechanical components such as the mirror and focus array it kind of makes sense that you may have to allow for lens/body combinations. Again though on a DSLR, using live view (so on sensor AF?) has always been spot on. This concept of having to deal with mfa/focus inconsistencies is not something I want to be dealing with on mirrorless :(
 
jj_glos said:
No I'm not, you're adding a compensation to your lens due to the camera system not identifying the correct in focus target.

The lens doesn't decide focus, the camera does.
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You're making a lot of assumptions about a system none of us properly understand on a technical level.

If as you say it's down to the camera alone then we should find that every lens has roughly the same AF accuracy just a variation in how quickly they do so based on their design but we know that's not the case.
 
simonbarker said:
You're making a lot of assumptions about a system none of us properly understand on a technical level.

If as you say it's down to the camera alone then we should find that every lens has roughly the same AF accuracy just a variation in how quickly they do so based on their design but we know that's not the case.
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I haven't made any assumptions to be honest, if you can point out where a lens is responsible for AF then great but I've never seen that in any spec for a lens to be honest? I've explained how the image 'sensor' be it the human eye or CPU determines if the image is sharp and in focus, then gives the green light. Something is squiffy here as the CPU thinks it is in perfect focus, as the lens is providing an image from which the AF accuracy is determined, the processing has to be at fault? If manually focusing the lens still results in front focus, then I could concede that I have even less of an idea what's going on than I do now! :D
 
snerkler said:
Calvin's also proven this too with the 85mm. Wilkinsons have now replaced his A7iii but this is also front focussing with the Sony 85mm so it's not looking more likely that it's the lens that's causing the issue rather than the camera as it would be unlikely to have two lemon cameras.
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Yep, I received a replacement A7III body on Wednesday and testing with the Sony 85mm f1.8 again showed front focussing of about an inch from a distance of approx 5ft at a 45 degree angle. I can clearly see it in the evf/screen. This is confirmed in magnified view. However, if i half press the shutter in magnified view, then the focus shifts back and snaps properly into place! Following a phone call to Wilkinson's on Thursday afternoon, it was agreed that I send the lens back to them for testing/possible replacement. I sent it back that same afternoon. I will update as and when.
 
So today was the day of the local camera shop's (Cambrian Photography) open day so along I went, looking forward to coming home with a zoom lens for the Sony.
First I tried the Tamron 28-75, that felt like it was designed for e-mount, being light and compact, and lovely to use.
Then I tried the Sony 24-105 f4. This was considerably chunkier and heavier, but still very nice to use.
So it was decision time - then I found out that both are still only available on pre-order (the Tamron rep said they had issued a statement and apology re another delay but expect to fulfil back-orders in six to eight weeks!!
I pre-ordered the Tamron, but still not sure I have made the right choice - any opinions out there from people who have used or own either lens??
 
jj_glos said:
I haven't made any assumptions to be honest, if you can point out where a lens is responsible for AF then great but I've never seen that in any spec for a lens to be honest? I've explained how the image 'sensor' be it the human eye or CPU determines if the image is sharp and in focus, then gives the green light. Something is squiffy here as the CPU thinks it is in perfect focus, as the lens is providing an image from which the AF accuracy is determined, the processing has to be at fault? If manually focusing the lens still results in front focus, then I could concede that I have even less of an idea what's going on than I do now! :D
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Being able to manual focus a lens accurately has no bearing on whether the lens or camera or both contribute to autofocus accuracy and tolerance tbh.

Do you agree that different lenses have different front/back focus problems on the same body? If so how do you explain this if it is only the camera that is responsible for the final focus, it just doesn’t make sense?

There are complicated algorithms that dictate where the focus should be. Could it not be the case that the camera ‘knows’ where focus should be, sends this info to the lens and then the lens doesn’t action this command correctly? This sounds pretty plausible to me.

Also, if lenses weren’t co-responsible for AF accuracy why do Sigma and Tamron have docks to allow you to fine tune the AF accuracy of the lens?

I can’t say for sure how obviously, but logic tells me from this info that the lens is at least in some way responsible for AF accuracy (y)
 
snerkler said:
Being able to manual focus a lens accurately has no bearing on whether the lens or camera or both contribute to autofocus accuracy and tolerance tbh.

Do you agree that different lenses have different front/back focus problems on the same body? If so how do you explain this if it is only the camera that is responsible for the final focus, it just doesn’t make sense?

There are complicated algorithms that dictate where the focus should be. Could it not be the case that the camera ‘knows’ where focus should be, sends this info to the lens and then the lens doesn’t action this command correctly? This sounds pretty plausible to me.

Also, if lenses weren’t co-responsible for AF accuracy why do Sigma and Tamron have docks to allow you to fine tune the AF accuracy of the lens?

I can’t say for sure how obviously, but logic tells me from this info that the lens is at least in some way responsible for AF accuracy (y)
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If you can manually focus a lens and it works, there isn't a physical problem with the lens. It means the lens is sharp and accurate. Once you start using AF it is driven by the camera, and the technical computational ability of the camera to determine if the subject is in focus. The camera controls the movement of the AF mechanism in the lens, it moves this mechanism until the camera thinks the image is in focus. The rules around how the camera decides the image is in focus is the crux of the issue as far as I can see?

I don't agree that any lens should be out on a mirrorless body, the tech should be preventing that if used properly. MFA on a DSLR, yes we know it happens but manual or live view AF have always been the accurate constant control that hit 100% every time.

I would love to know how a camera body knows where focus should be and tells the lens what to do, it needs to take the scene/AF point into account, focal length, aperture, subject etc. The lens feeds the camera information, the camera body makes the decision. This is based around me thinking that the end focus result is all based around the image and best focus of the highlighted area under the AF point, as you would manually... If the camera doesn't do this, then there will always be problems.

You may be right though, the camera may use prediction rather than verification, and the algorithm it uses just doesn't work for all lenses? That kinda makes sense to me. So possibly this is the root of the issue?

Edit: If the camera, in the pursuit of speed takes stock of the situation and decides the lens needs to move 'x' number of clicks and the scene will be in focus rather than actually verifying it is in focus, then yes if the translation of clicks to the lens is out for some reason, it's all going to end badly :D You'd think in single AF it would take it's time and make sure, having inconsistencies if C-AF I'd expect as that is generally about prediction. I wonder if pre-AF plays any part?

I've never seen this behaviour with Fuji, or Canon where using live view is the control that you set the MFA by when using software like FoCal.

Edit: Full disclosure, I'm about ten pints of Scrumpy Jack in, so this may all make no sense at all :D
 
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david357 said:
I pre-ordered the Tamron, but still not sure I have made the right choice - any opinions out there from people who have used or own either lens??
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A little optimistic given that the Tamron has just come out and I'm not sure anyone posting here has one yet.

The reports seem very positive though, if there's no glaring flaw and you can live without the extra range then the Tamron seems a far more sensible choice at half the price.
 
jj_glos said:
I haven't made any assumptions to be honest, if you can point out where a lens is responsible for AF then great but I've never seen that in any spec for a lens to be honest? I've explained how the image 'sensor' be it the human eye or CPU determines if the image is sharp and in focus, then gives the green light. Something is squiffy here as the CPU thinks it is in perfect focus, as the lens is providing an image from which the AF accuracy is determined, the processing has to be at fault? If manually focusing the lens still results in front focus, then I could concede that I have even less of an idea what's going on than I do now! :D
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You've made several, you're assuming the camera and lens work a specific way but if that were correct then it shouldn't be possible to have front or back focusing occurring.

Another example for you, the AF on my FE 90mm is worse than my other lenses, if your assumption about the camera doing everything were correct then that shouldn't be possible.
 
simonbarker said:
You've made several, you're assuming the camera and lens work a specific way but if that were correct then it shouldn't be possible to have front or back focusing occurring.

Another example for you, the AF on my FE 90mm is worse than my other lenses, if your assumption about the camera doing everything were correct then that shouldn't be possible.
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Sorry, I didn't realise that it was an assumption that the camera body determines whether AF has been secured or not whilst controlling the lens. It's how all AF cameras I have ever used have worked, sorry I assume they have worked. Must be some other non AF acquisition related way that they work then. :D

I am interested in how you think they work, purely in a functional layman's way.

The AF performance, with regards to speed and operation in low light can obviously be down to a lens as that is where the AF motors are and the lens is responsible for transmitting the light/image that the camera uses to determine focus. It's easy to see how this might result in no focus, or missed focus but consistent front focus? Not sure about that myself.

None of the mirrorless systems or even non mirrorless systems using live view have ever shown anything but 100% accuracy in single shot AF with good light. Not needing MFA with mirrorless is a headline feature, that and WYSIWYG is pretty much the main reason I like mirrorless.
 
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