Lens quality issues - why no 'standard' benchmarks?

LondonLeftie · Sep 9, 2008

spt_gb said:
Here's your first fallacy. Lens manufacturers are already meeting the terms of the law. They sell > lenses that fit the cameras that they say they will. They focus to within reasonable tolerances and > the images projected meet acceptable standards (and formal numbers are NOT required to specify > this last bit). If a lens is sold that doesn't do this then they will repair or replace the lens as the law > requires. This is just like any other mass produced product.

I am not and lawyer and neither are you – so who knows if they do meet the conditions set in law – and of course what law? Which country? But the point is this: you are telling me that lenses meet acceptable standards – but then not all lenses do. This is a fact. So, which lenses do not? Well, we need to test them to find out. And what is the ‘official’ test that tells you this? I have no idea – and nor to many people – surely this can not be a good thing from the standpoint of the consumer if they are not able to tell how to tell if they have a good version of a lens, no matter the absolute cost.

This is my point – and you can speculate all you want about whether Canon or Nikon do meet the conditions of your local laws – but as a consumer I can say that I am not happy and nor are many other people about spending money like a pig-in-a-poke. It doesn’t make sense.

spt_gb said:
You are getting a lens that fits a specific camera type, that focusses (some models may be manual > focus), that has an approximate focal length (or range of lengths) and is of merchantable quality. > This doesn't mean perfect, or that the manufacturer has to provide proof of quality. If it doesn't > meet any of the above requirements then the retailer must replace, repair or refund.

I have at no point said that a lens should be 'perfect' - I fully recognise that this is technically impossible. I have said that I expect to be able to know if my lens is a good, bad or average copy. And without any impartial metrics, I see no way that it is possible to tell, short of trying lots and seeing which is best (but then again, how many is 'enough'?

An I disagree – a good manufacturer should have to provide proof of quality – if the customer is unable (due to the cost of purchasing lens testing machines and software for their bedroom) to test a lens and know for sure themselves.

And you never answered my question - how do you know that your lenses are in the top, say, 20% of their model range? Shot answer is you don't, but you've avoided answering.

spt_gb said:
Why not? I keep telling you that providing a full performance report with the > lens costs money. You want something extra that costs money then you pay > for it. This is the way that the world works, get used to it.

Very pithy, but again no. There must be somewhere a Master copy of this lens, the 'best' copy out there (perhaps in a Nikon or Canon safe somewhere, who knows?) that they use as a reference model. And if that is so, then there is a standard. And if there is a standard, then the lens must be being manufactured to these ‘standards’. And if they are using these standards then they are also measuring them and adjusting the manufacturing process to make sure that these standards are met. Making a lens is not trial and error, but I assume done to measured values. And if the values are recorded then why are they not published so that we can measure them, in a standard and easy way. (done back at base – how much could this really cost?! – or done in shop so that you know your £1200 is well spent ). That way there would be no more forum chit-chat about better or worse copies, just good acceptable ones or bad unacceptable ones.

spt_gb said:
Rubbish back at you. You are asking the manufacturer for a printed > performance report for each lens. Why do you think that this costs them > nothing?

I have I at any point requested that each lens come with an individual test report, another creation of yours (not a bad idea though) that you have attributed to me. What I have said however is that a manufacturer should be able to demonstrate to me that his product is able to produce images of a certain standard (their reference standard of course) - which is what is currently lacking. The situation as of now is that we are asked to 'trust' , however accurate this might or might not be, the brand Canon more than Sigma more than Tamron , for example (and its only an example). Or, as you suggest we are asked to buy multiple copies, test them , then send back the less good ones. Or look through forums all day trying to see if we have a forum debatable acceptable copy. What a waste of time when it would be far easier to have some metric to measure against.

spt_gb said:
IF you ever get to be a 'great' photographer (and if you spend all of your time in these forums > arguing about lenses then this is doubtfull) one of the things that you will have to learn is how to > get the best out of the equipment you have at hand (and this will include checking that it's working > properly), but that will be a secondary consideration to knowing how to capture the shots that > makes money. We have equipment today that the great photographers of the past would have > killed for, but they still managed to take great photographs with what they had.

A good point, learning how to use equipment is all part of the job. But if your equipment is not up to spec then however good you are you won’t be taking the best photo possible. If I am a pro I want to know that my lens is good – but I might also want to know just HOW good it is – even if I choose to use cheap lenses (which will perform worse than good ones, but then I know that ‘cos I’m a pro

– but how much worse is what I want to be able to ask, and answer)

http://www.lightmatter.co.uk

spt_gb · Sep 9, 2008

and part time barack room lawyer. I'm going to make my points one last time and then I'm done.

bigbadlemon wrote:
...

LondonLeftie said:
I am not and lawyer and neither are you – so who knows if they do
meet the conditions set in law – and of course what law?

If you can't state which law or laws are being broken and why, how can you claim this as a justification for requiring performance reports?

No law in the world requires manufacturers to sell only perfect copies of an item. Local laws MAY set minimum standards, depending on the item being sold, but AFAIK no country requires manufacturers to state by how much they have exceeded these standards for each specific example. As for the UK, I am reasonably converstant with the Sale of Goods act which governs here. Perhaps you'd like to point out which part of it is being broken by lens manufacturers?

LondonLeftie said:
... But the point is this: you are telling me that lenses meet
acceptable standards – but then not all lenses do. This is a fact.
So, which lenses do not?

The important point here is that it depends on the buyer. People look for different things in a product, lenses especialy so. You, for example, seem to think that the one and only important criteria is pixel sharp corners when wide open. It doesn't seem to occur to you that the images will look sharp in quite large prints, more so if you stop down 1/3rd to 2/3rds of a stop. Colour and contrast are much more important parameters to experienced photographers, but it's up to you to tell the retailer that the corners aren't acceptable and ask for a replacement.

...

LondonLeftie said:
but as a
consumer I can say that I am not happy and nor are many other people
about spending money like a pig-in-a-poke. It doesn’t make sense.

As a consumer you have the right to buy or not to buy. As manufacturers Canon, Nikon et al have the right not to sell, or not to sell at the price you want to pay or under the conditions you want to apply. Until you recognise this your arguments are going nowhere. What's in it for the manufacturer?

...

LondonLeftie said:
I have at no point said that a lens should be 'perfect' - I fully
recognise that this is technically impossible. I have said that I
expect to be able to know if my lens is a good, bad or average copy.

and you've repeatedly made clear that you want to cherry pick the best copy, and at the same price as all of the others. What's in this for the manufacturer and/or retailer?

...

LondonLeftie said:
An I disagree – a good manufacturer should have to provide proof of
quality – if the customer is unable (due to the cost of purchasing
lens testing machines and software for their bedroom) to test a lens
and know for sure themselves.

This is pure pixel peeper mentality. You might not be able to get scientific numbers in your bedroom, but if you are unable to get a feel for how the lens is performing with some simple testing then you've wasted your money on a DSLR. A good photographer can take a below average lens and create a fantastic image. A pixel peeper can't see a fantastic image for all those lousy pixels (no-matter that they don't show up in a print).

LondonLeftie said:
And you never answered my question - how do you know that your lenses
are in the top, say, 20% of their model range? Shot answer is you
don't, but you've avoided answering.

Short answer is that it doesn't matter. If you think that they are good enough for your purposes then you can learn to make them perform. For the life of me I don't understand why someone who doesn't comprehend this has bought a 70-200 IS. It's like a learner driver complaining that they haven't got a certificate from Ford to tell them exactly how much power their Focus ST is producing, while ignoring how good or bad it is at cornering.
...

LondonLeftie said:
Very pithy, but again no. There must be somewhere a Master copy of
this lens, the 'best' copy out there (perhaps in a Nikon or Canon
safe somewhere, who knows?) that they use as a reference model.

Exactly HOW would Canon, Nikon etc know how good a given lens was without measuring it. How would they do this without it costing money? Why would any customer buy an "average" rated lens when an "excelent" rated lens costs the same money? How would they get rid of their stock of lower rated lenses?

LondonLeftie · Sep 9, 2008

says the computer programmer?!

Just read the posts given by others on this matter to see that, as far as this thread is concerned, you are in the minority. Not that this is good or bad, but does lead people to think that perhaps you dont have a monopoly on the 'right' answer. So far no one has come to your defense - or am I mistaken?

spt_gb said:
If you can't state which law or laws are being broken and why, how can you > claim this as a justification for requiring performance reports?

spt_gb said:
No law in the world requires manufacturers to sell only perfect copies of an > item. Local laws MAY set minimum standards, depending on the item being sold, > but AFAIK no country requires manufacturers to state by how much they have > exceeded these standards for each specific example.

Again, please stop banging on about perfect copies - it means nothing. What does make sense however is a lens that meets or exceeds specification! That's a perfect system to me, not a perfect lens.

I imagine that you are 'reasonably converstant' with the Sale of Goods act (year anyone? haha) but the point here isn't to go to court and prove I can win, but to suggest what a standard might be useful for consumers. You'll be eating your hat if someone does take it that far and win, just because you can't imagine why a standard might be useful. Just accept it, it might be useful!

spt_gb said:
The important point here is that it depends on the buyer. People look for > different things in a product, lenses especialy so. You, for example, seem to > think that the one and only important criteria is pixel sharp corners when wide > open. It doesn't seem to occur to you that the images will look sharp in quite > large prints, more so if you stop down 1/3rd to 2/3rds of a stop. Colour and > contrast are much more important parameters to experienced photographers, > but it's up to you to tell the retailer that the corners aren't acceptable and ask > for a replacement.

Never mentioned wide open, nor the rest of what you mentioned above. I accept all the complexities of a standard test for all lenses. But , that is not my point. My point is not that this might be simple, but that an attept should be made.

And again, proving that something isn't acceptable requires you to know what IS acceptable. Just think - with new 35 mp sensors on the way, the old lenses just won't cut it - how will manufacturers be able to differentiate between lenses that can resolve 35 mp and those that can't without standards? and the public?

spt_gb said:
As a consumer you have the right to buy or not to buy. As manufacturers > Canon, Nikon et al have the right not to sell, or not to sell at the price you > want to pay or under the conditions you want to apply. Until you recognise this > your arguments are going nowhere. What's in it for the manufacturer?

Yes, well said. I also have the right to know what I am buying, at least here in the UK. And most people have a duty to be able to prove what they are selling.

spt_gb said:
and you've repeatedly made clear that you want to cherry pick the best copy, > and at the same price as all of the others. What's in this for the manufacturer > and/or retailer?

I'm not sure I get this - is this envy or something? I think that we should ALL be able to cherry pick the best lens - ie. all lenses meet a standard that we can test. That simple. It makes the consumers life easier, builds confidence and provides lens manfacturers with happy clients. There might be a cost - but then it's a cost that really must be very small compared to the price of a lens - and might even be less than the cost of dealing with faulty returns - but you can't think that far ahead!

spt_gb said:
An I disagree – a good manufacturer should have to provide proof of
quality – if the customer is unable (due to the cost of purchasing
lens testing machines and software for their bedroom) to test a lens
and know for sure themselves.

spt_gb said:
This is pure pixel peeper mentality. You might not be able to get scientific > numbers in your bedroom, but if you are unable to get a feel for how the lens is > performing with some simple testing then you've wasted your money on a > DSLR. A good photographer can take a below average lens and create a > fantastic image. A pixel peeper can't see a fantastic image for all those lousy > pixels (no-matter that they don't show up in a print).

Making lenses is a science - not an art. At least not anymore. To pretend otherwise, afaik, is just pretending that you know more than you do. Lenses are precision tools, made with precision equiptment - everything is measured. Accept it. I might be able to get a feel for a lense - but can the average consumer? Sould it be so hard to do? No.

spt_gb said:
Short answer is that it doesn't matter. If you think that they are good enough > for your purposes then you can learn to make them perform. For the life of me > I don't understand why someone who doesn't comprehend this has bought a > 70-200 IS. It's like a learner driver complaining that they haven't got a > certificate from Ford to tell them exactly how much power their Focus ST is > producing, while ignoring how good or bad it is at cornering.

No , another computer programmer answer. You can't make a defective lens perform as well as a well made well performing one. However hard you try. You like car examples don't you? But they don't work. All cars have stats to them!

spt_gb said:
Exactly HOW would Canon, Nikon etc know how good a given lens was without > measuring it. How would they do this without it costing money? Why would > any customer buy an "average" rated lens when an "excelent" rated lens costs > the same money? How would they get rid of their stock of lower rated lenses?

Are you telling me they build the lenses without measuring them along the way? I can't believe that - doesn't make sense. Build the lenses - don't measure as you go and hope for the best at the end? Sounds crackpot to me.

--
http://www.lightmatter.co.uk

Performance related pay? Nah, pay related performance!

ZenerEffect · Sep 10, 2008

Even if the camera manufacturers were to adhere to the Four Sigma, which is — at first glance — an apparently HIGH efficiency of 99.4%, we'd still end up with (potentially) six defective lenses per 1000 cameras.

And bearing in mind that this applies to the Six Sigma bench-mark for each and every one of the multiple pieces of glass that make up a single camera lens, I'm not all that confident that I'm gonna get a theoretically optically "perfect" lens.

But... will I ever know?

Cheers

digifan · Sep 10, 2008

question.
But you ramble on on how he doesn't get it.

From a consumer point of view bigbadlemon has a very good point. There are a lot of lenses from a number of makers, that don't perform according to the expected level.

There is only the mfr "word" for it they are ok. There's no quality sheet that says, this lens is whitin these limits.
There are so many lenses that are flawed you would expect they'd be on the ball.

spt_gb said:
bigbadlemon wrote:
...

spt_gb said:

I am not and lawyer and neither are you – so who knows if they do
meet the conditions set in law – and of course what law?

Click to expand...

If you can't state which law or laws are being broken and why, how
can you claim this as a justification for requiring performance
reports?
No law in the world requires manufacturers to sell only perfect
copies of an item. Local laws MAY set minimum standards, depending on
the item being sold, but AFAIK no country requires manufacturers to
state by how much they have exceeded these standards for each
specific example. As for the UK, I am reasonably converstant with the
Sale of Goods act which governs here. Perhaps you'd like to point out
which part of it is being broken by lens manufacturers?

spt_gb said:

... But the point is this: you are telling me that lenses meet
acceptable standards – but then not all lenses do. This is a fact.
So, which lenses do not?

Click to expand...

The important point here is that it depends on the buyer. People look
for different things in a product, lenses especialy so. You, for
example, seem to think that the one and only important criteria is
pixel sharp corners when wide open. It doesn't seem to occur to you
that the images will look sharp in quite large prints, more so if you
stop down 1/3rd to 2/3rds of a stop. Colour and contrast are much
more important parameters to experienced photographers, but it's up
to you to tell the retailer that the corners aren't acceptable and
ask for a replacement.

...

spt_gb said:

but as a
consumer I can say that I am not happy and nor are many other people
about spending money like a pig-in-a-poke. It doesn’t make sense.

Click to expand...

As a consumer you have the right to buy or not to buy. As
manufacturers Canon, Nikon et al have the right not to sell, or not
to sell at the price you want to pay or under the conditions you want
to apply. Until you recognise this your arguments are going nowhere.
What's in it for the manufacturer?

...

spt_gb said:

I have at no point said that a lens should be 'perfect' - I fully
recognise that this is technically impossible. I have said that I
expect to be able to know if my lens is a good, bad or average copy.

Click to expand...

and you've repeatedly made clear that you want to cherry pick the
best copy, and at the same price as all of the others. What's in this
for the manufacturer and/or retailer?

...

spt_gb said:

An I disagree – a good manufacturer should have to provide proof of
quality – if the customer is unable (due to the cost of purchasing
lens testing machines and software for their bedroom) to test a lens
and know for sure themselves.

Click to expand...

This is pure pixel peeper mentality. You might not be able to get
scientific numbers in your bedroom, but if you are unable to get a
feel for how the lens is performing with some simple testing then
you've wasted your money on a DSLR. A good photographer can take a
below average lens and create a fantastic image. A pixel peeper can't
see a fantastic image for all those lousy pixels (no-matter that they
don't show up in a print).

spt_gb said:

And you never answered my question - how do you know that your lenses
are in the top, say, 20% of their model range? Shot answer is you
don't, but you've avoided answering.

Click to expand...

Short answer is that it doesn't matter. If you think that they are
good enough for your purposes then you can learn to make them
perform. For the life of me I don't understand why someone who
doesn't comprehend this has bought a 70-200 IS. It's like a learner
driver complaining that they haven't got a certificate from Ford to
tell them exactly how much power their Focus ST is producing, while
ignoring how good or bad it is at cornering.
...

spt_gb said:

Very pithy, but again no. There must be somewhere a Master copy of
this lens, the 'best' copy out there (perhaps in a Nikon or Canon
safe somewhere, who knows?) that they use as a reference model.

Click to expand...

Exactly HOW would Canon, Nikon etc know how good a given lens was
without measuring it. How would they do this without it costing
money? Why would any customer buy an "average" rated lens when an
"excelent" rated lens costs the same money? How would they get rid of
their stock of lower rated lenses?

--
Digifan

digifan · Sep 10, 2008

you didn't get it either.

The point bigbadlemon makes is, that you want to make shure a lens you buy from any mfr is between stated (known standard) limits.
The point exactly is that a 70-300 isn't like a 70-300 across brands etc.

K1000Photographer said:
bigbadlemon said:

http://it.answers.yahoo.com/question/?qid=20080908082213AAq0DfX

But still, how do you KNOW when you've got a dud if the lens is
equally and evenly defective over the entire surface?

A defective edge can be seen because it performs badly compared to
the rest of the lens - but an image that is all bad (but not
'terrible') might perhaps never be noticed. Right?

Click to expand...

If you did get a dud lens, you should be able to see something wrong
with the images or performance. One big issue is that much of a lens'
performance is subjective.

Which is better. a Sigma 70-300 APO or a Tamron 70-300 DI? The Tamron
is sharper but I would take the Sigma.

--
Digifan

spt_gb · Sep 10, 2008

and apparently completely waisting my breath on is that if manufacturers give some kind of quality rating to individual lenses then the good ones will have to cost more for two reasons. Firstly it will cost more to give them a ranking (there will be at least one extra test required), and secondly they will be unable to sell any lower rated lenses otherwise.

With mass produced items (of any type) the manufacturer can either sell all at the same price, with the buyer getting pot luck that it will be anything between lowest acceptable quality and perfect, or they can sort by performance and charge extra for the better ones. In the computing world the latter happens all of the time. CPUs are tested off of the assembly line and sold based on the speed they will run at. In the automotive world the former is more common (Ford have a fixed list price for the Focus ST for example, but the actual power of each engine will be different by a more or less subtle amount than the numbers Ford quote).
There are only ever three options that work:-
1) Sell all the same price. Some may be not so good, but the price is lowest.
2) Price by tested performance. Price is high for best examples
3) Use lots of QC so that all are equaly excelent. All are expensive.

He doesn't get an option 4. He can't expect to automaticaly get the best available example for the same price as the worst. The only thing he can do in the lens world is chose between option 1 or option 3.

digifan said:
question.
But you ramble on on how he doesn't get it.

From a consumer point of view bigbadlemon has a very good point.
There are a lot of lenses from a number of makers, that don't perform
according to the expected level.

There is only the mfr "word" for it they are ok. There's no quality
sheet that says, this lens is whitin these limits.
There are so many lenses that are flawed you would expect they'd be
on the ball.

exp1orer · Sep 10, 2008

all manufacturers make their products based on 'acceptable' range called tolerance. there's no such thing as 'zero' tolerance in hardware manufacturing.

--

http://www.exp1orer.com

AnandaSim · Sep 10, 2008

ZenerEffect said:
Even if the camera manufacturers were to adhere to the Four Sigma,
which is — at first glance — an apparently HIGH efficiency of 99.4%,
we'd still end up with (potentially) six defective lenses per 1000
cameras.

ZenerEffect said:
But... will I ever know?

Yes. But we don't even know what result optically, what one sigma is.
The makers don't publish the result for the average or one sigma
They know, we don't.

Remember the Hubble!

--

Ananda
http://anandasim.blogspot.com/

digifan · Sep 10, 2008

you will never "get" his (OP) point.

Well maybe I must be glad that there are so many people who like to get f#cked. Means you can easily be my victim too and I have nothing to fear from you since you think certain things are normal.

spt_gb said:
and apparently completely waisting my breath on is that if
manufacturers give some kind of quality rating to individual lenses
then the good ones will have to cost more for two reasons. Firstly it
will cost more to give them a ranking (there will be at least one
extra test required), and secondly they will be unable to sell any
lower rated lenses otherwise.
With mass produced items (of any type) the manufacturer can either
sell all at the same price, with the buyer getting pot luck that it
will be anything between lowest acceptable quality and perfect, or
they can sort by performance and charge extra for the better ones. In
the computing world the latter happens all of the time. CPUs are
tested off of the assembly line and sold based on the speed they will
run at. In the automotive world the former is more common (Ford have
a fixed list price for the Focus ST for example, but the actual power
of each engine will be different by a more or less subtle amount than
the numbers Ford quote).
There are only ever three options that work:-
1) Sell all the same price. Some may be not so good, but the price is
lowest.
2) Price by tested performance. Price is high for best examples
3) Use lots of QC so that all are equaly excelent. All are expensive.

He doesn't get an option 4. He can't expect to automaticaly get the
best available example for the same price as the worst. The only
thing he can do in the lens world is chose between option 1 or option
3.

Today it's easy to get the level of QC needed to produce lenses within a specific tolerance. The tolerance is namely allready known after befor during and after production. It's easy to issue a report of such findings. And I bet ya the mfr have these for every item produced. They got a serial number etc and there's computer caliration involved. So duh.

spt_gb said:
digifan said:

question.
But you ramble on on how he doesn't get it.

From a consumer point of view bigbadlemon has a very good point.
There are a lot of lenses from a number of makers, that don't perform
according to the expected level.

There is only the mfr "word" for it they are ok. There's no quality
sheet that says, this lens is whitin these limits.
There are so many lenses that are flawed you would expect they'd be
on the ball.

Click to expand...

--
Digifan

digifan · Sep 10, 2008

exp1orer said:
all manufacturers make their products based on 'acceptable' range
called tolerance. there's no such thing as 'zero' tolerance in
hardware manufacturing.

and that's exactly his point. They should publish the tolerance so to say. In otherwords they (mfr) could include the production report of the lens that it passed the QC, and the measured items were such and such falling between so and so borders. Should be very easy to produce these since all these lenses are calibrated on a computer.

--
Digifan

K1000Photographer · Sep 10, 2008

sigh

Well, If the lower quality lens has better objective numbers, how much value can one place in the same kinds of numbers if the were applied to every lens as standards? Then, how would the consumer know if the lens met those number or not? The consumer is then left to figure out if a lens is good or bad by the same means they have at their disposal at the moment, unless they can do their own MTF test.

LondonLeftie · Sep 10, 2008

Someone is awake at the wheel!

Why is everyone so against knowing the quality of what they buy?!

I just don't get it!

--
http://www.lightmatter.co.uk

Performance related pay? Nah, pay related performance!

LondonLeftie · Sep 10, 2008

spt_gb said:
and apparently completely waisting my breath on is that if manufacturers give some kind of quality rating to individual lenses then the good ones will have to cost more for two reasons. Firstly it will cost more to give them a ranking (there will be at least one extra test required), and secondly they will be unable to sell any lower rated lenses otherwise.

Are you telling me that you don't need to know how good you lens is so that manufactures can sell the 'dud' ones for the same price as the good ones? Are you serious?! If they can't sell the lower rated ones (which they could for less money) then it's because they are s*it! I hope you get them! plonker.

spt_gb said:
With mass produced items (of any type) the manufacturer can either sell all at > the same price, with the buyer getting pot luck that it will be anything > between lowest acceptable quality and perfect, or they can sort by performance and > charge extra for the better ones. In the computing world the latter happens all > of the time. CPUs are tested off of the assembly line and sold based on the > speed they will run at. In the automotive world the former is more common (Ford > have a fixed list price for the Focus ST for example, but the actual power of each > engine will be different by a more or less subtle amount than the numbers Ford > quote).

CPU's are ALWAYS marked for a given speed - and sold as such. Man you have no clue.This is like clubbing a kitten!

spt_gb said:
There are only ever three options that work:-
1) Sell all the same price. Some may be not so good, but the price is lowest.

Morally wrong - my point!

spt_gb said:
2) Price by tested performance. Price is high for best examples

Excellent idea - the world is full rich, poor and all those inbetween - each to his own budget i say! This is not socialism - but lens buying! Wack on the head again!

spt_gb said:
3) Use lots of QC so that all are equaly excelent. All are expensive.

Right again! But soooo much cheaper than dealing with returns! Take your head out of the sand!

spt_gb said:
He doesn't get an option 4. He can't expect to automaticaly get the best > available example for the same price as the worst. The only thing he can do in > the lens world is chose between option 1 or option 3.
digifan wrote:

I don't need an option 4! 1, 2 or 3 work fine - just tell me what I am paying for and promise me the right spec! I want to know if my lens will work well with a 5, 12, 24 or 124 megapixel camera - not have to guess!

Jesus h christ - you spend too much time with c++ or sharp whatever it is.

--
http://www.lightmatter.co.uk

Performance related pay? Nah, pay related performance!

spt_gb · Sep 10, 2008

and more stubborn than a field full of mules. You can't even be bothered to check facts before denying them.
Read this http://en.wikipedia.org/wiki/Product_binning

Links are set on a CPU based on how it tests out to set it's clock speed. On some older AMD processors you could even get creative with conductive paint and change the rated clock speed yourself.

Now give me a single example of a mass produced product that sells with an individual performance report and without price differential based on performance.

bigbadlemon said:
LondonLeftie said:

and apparently completely waisting my breath on is that if manufacturers give some kind of quality rating to individual lenses then the good ones will have to cost more for two reasons. Firstly it will cost more to give them a ranking (there will be at least one extra test required), and secondly they will be unable to sell any lower rated lenses otherwise.

Click to expand...

Are you telling me that you don't need to know how good you lens is
so that manufactures can sell the 'dud' ones for the same price as
the good ones? Are you serious?! If they can't sell the lower rated
ones (which they could for less money) then it's because they are
s*it! I hope you get them! plonker.

LondonLeftie said:

With mass produced items (of any type) the manufacturer can either sell all at > the same price, with the buyer getting pot luck that it will be anything > between lowest acceptable quality and perfect, or they can sort by performance and > charge extra for the better ones. In the computing world the latter happens all > of the time. CPUs are tested off of the assembly line and sold based on the > speed they will run at. In the automotive world the former is more common (Ford > have a fixed list price for the Focus ST for example, but the actual power of each > engine will be different by a more or less subtle amount than the numbers Ford > quote).

Click to expand...

CPU's are ALWAYS marked for a given speed - and sold as such. Man you
have no clue.This is like clubbing a kitten!

LondonLeftie said:

There are only ever three options that work:-
1) Sell all the same price. Some may be not so good, but the price is lowest.

Click to expand...

Morally wrong - my point!

LondonLeftie said:

2) Price by tested performance. Price is high for best examples

Click to expand...

Excellent idea - the world is full rich, poor and all those inbetween

each to his own budget i say! This is not socialism - but lens

buying! Wack on the head again!

LondonLeftie said:

3) Use lots of QC so that all are equaly excelent. All are expensive.

Click to expand...

Right again! But soooo much cheaper than dealing with returns! Take
your head out of the sand!

LondonLeftie said:

He doesn't get an option 4. He can't expect to automaticaly get the best > available example for the same price as the worst. The only thing he can do in > the lens world is chose between option 1 or option 3.
digifan wrote:

Click to expand...

I don't need an option 4! 1, 2 or 3 work fine - just tell me what I
am paying for and promise me the right spec! I want to know if my
lens will work well with a 5, 12, 24 or 124 megapixel camera - not
have to guess!

Jesus h christ - you spend too much time with c++ or sharp whatever
it is.

--
http://www.lightmatter.co.uk

Performance related pay? Nah, pay related performance!

exp1orer · Sep 10, 2008

..unless the manufacturer is so-so...when the products are shipped for retails, that means they passed the manufacturer's QC standard. why should they include production report? please tell me which manufacturers include their production report when they sell their products. should every manufacturer of more 5,000 parts of the cars include their production report in each piece of parts they supply to car manufacturers? and should every car manufacturer include every part production report of the parts supplier to every car they manufacture? think again before you suggest that idea...manufacturers are only obliged to disclose their manufacturing reports if there is a court order i believe.

digifan said:
exp1orer said:

all manufacturers make their products based on 'acceptable' range
called tolerance. there's no such thing as 'zero' tolerance in
hardware manufacturing.

Click to expand...

and that's exactly his point. They should publish the tolerance so to
say. In otherwords they (mfr) could include the production report of
the lens that it passed the QC, and the measured items were such and
such falling between so and so borders. Should be very easy to
produce these since all these lenses are calibrated on a computer.

--
Digifan

--

http://www.exp1orer.com

exp1orer · Sep 10, 2008

...it's simple as it is.

bigbadlemon said:
Someone is awake at the wheel!

Why is everyone so against knowing the quality of what they buy?!

I just don't get it!

--
http://www.lightmatter.co.uk

Performance related pay? Nah, pay related performance!

--

http://www.exp1orer.com

LondonLeftie · Sep 11, 2008

and the better ones get a higher CPU - so you know what you're getting.

Just because you might be able to force the cpu higer, ie clocking, means that you get something extra but only at a risk. Either way, you get a minimum guarantee of speed.

So the same with a lens would be exactly what I am after. Not all lenses can cope with the new 24mp sony sensor - so people need to know! I don't want to purchase a high mp sensor camera to not know if a lens might, or might not, make the grade depending on Canon's quality control process. We NEED to know.

Well, everyone expet you this appears to be.

--
http://www.lightmatter.co.uk

Performance related pay? Nah, pay related performance!

LondonLeftie · Sep 11, 2008

I said I want to know how 'good' my lens is - I want some metric that I can compare my lens against - not an individual report in each box. Where did you get that from?

Otherwise - how will I ever know what future generation of sensors it is possible of resolving?! 24mp? 36? 67?

Lens manufactures will at some point need to specify, so why not sooner rather than later?

--
http://www.lightmatter.co.uk

Performance related pay? Nah, pay related performance!

spt_gb · Sep 11, 2008

Now you've admitted that CPUs ARE speed binned, perhaps you could point to an example where the faster clocked versions of the same CPU are sold for the same price as the slower ones.

Once you figure out that this doesn't happen, that you need to pay more for the higher rated part, you need to ask yourself how much more a lens given a rating of "excelent" would have to cost before you would think about buying one marked only as "good" instead. Unless the manufacturer provides a big enough price differential then they won't sell any lower rated parts. The lenses cost the same to make, and the manufacturer wants to make a profit on whatever they sell, so the lower rated parts would cost about the same as the unrated lenses sold at the moment and the high rated parts would sell for a lot more.

bigbadlemon said:
and the better ones get a higher CPU - so you know what you're getting.

Just because you might be able to force the cpu higer, ie clocking,
means that you get something extra but only at a risk. Either way,
you get a minimum guarantee of speed.

So the same with a lens would be exactly what I am after. Not all
lenses can cope with the new 24mp sony sensor - so people need to
know! I don't want to purchase a high mp sensor camera to not know if
a lens might, or might not, make the grade depending on Canon's
quality control process. We NEED to know.

Well, everyone expet you this appears to be.

--
http://www.lightmatter.co.uk

Performance related pay? Nah, pay related performance!

Lens quality issues - why no 'standard' benchmarks?

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