Is the Sigma 50mm 1.4 REALLY soft at 1.4?

DreDaze wrote in post #15043992
i never understand how people posting shots of their lens working at f1.4 has any relation to whether the op's lens works at f1.4...

Because 1) the impression that the sigma generally is soft is false and 2) you can send the lens in and have it calibrate if it is indeed focusing incorrectly. If budget is no concern, it seems silly to move from the sigma 1.4 to the slower less robust and less pleasing Canon 1.8.

TeamSpeed wrote in post #15044114
Because 1) the impression that the sigma generally is soft is false and 2) you can send the lens in and have it calibrate if it is indeed focusing incorrectly. If budget is no concern, it seems silly to move from the sigma 1.4 to the slower less robust and less pleasing Canon 1.8.

I'm one of those who fail to see why a new, just out of the box, lens (from any manufacturer) should need to go back to the manufacturer for calibrating.
Calibrating to what exactly? To within tolerance presumably - but that should be a known parameter during the lens design.

PaulB wrote in post #15044165
I'm one of those who fail to see why a new, just out of the box, lens (from any manufacturer) should need to go back to the manufacturer for calibrating.
Calibrating to what exactly? To within tolerance presumably - but that should be a known parameter during the lens design.

I cannot answer that, but there are 2 factors to accuracy, the body and lens. Why do so many Canon cameras go back for calibration? Ditto on their lenses? They know their own design, and if your argument would hold anywhere, it would be with Canon bodies and Canon lenses. 3rd party manufacturers are at a disadvantage.

However that being said, Canon offers MFA to help, and Sigma's new lens line allows you to purchase a device that allows you to calibrate your lenses at home. This means when your body and lens don't behave properly due to both being at extremes of their tolerances (remember a micrometer difference from what the AF sensors see to what the sensor records can produce front or backfocus, whether from lens or body), you can tweak everything to your heart's content without sending it in.

Sure it is a bit annoying and inconvenient to send the lens in, but I was happy I did. The lens performs outstandingly now. I also included the cost of shipping in with my purchase decision on what price to pay so that overall, I still ended up with a great deal.

So would I get a Sigma f1.4 lens that I have to send in to create a tool that is sharp at f1.4 vs getting the Canon f1.8? Yes, every time. Would I instead consider the Canon f1.4? Nope, as I have had the opportunity to deal with the AF failure on those lenses, and have taken them apart. I don't like what I see inside for the $300+ I would spend. I don't like its bokeh either.

Of the 3 50mm fast primes under $500 from Canon and Sigma, the best value, even with sending it in for calibration (or especially because of), the Sigma produces the best results.

Also, consumers want to spend less but get more, and that is nearly impossible to accomplish. Each 9 after the decimal, when addressing up time of computer systems, quality of goods, reduction of tolerances, etc costs exponentially more the farther you go out. So 99% accuracy will cost everyone much less than 99.9%, and especially so for 99.99%. Now if we are at 95% accuracy, you would reasonably assume there are some things that could be put into effect to bring us closer to 99%, but I don't know the technical details to argue where.

Has anyone posted the ISO crops from the digital picture? It shows this lens to be soft @ f/1.4, but not "that" soft. What I don't like about this lens is that the corners are just as soft at f/2.8 as f/4. In contrast to the Canon that is extremely sharp through the entire frame at f/4.

http://www.the-digital-picture.com …omp=0&FLIComp=0​&APIComp=0

PaulB wrote in post #15044165
I'm one of those who fail to see why a new, just out of the box, lens (from any manufacturer) should need to go back to the manufacturer for calibrating.
Calibrating to what exactly? To within tolerance presumably - but that should be a known parameter during the lens design.

Why do we have lens MA function then. But I do agree the wuality controls should be better. I hope with new changes at Sigma it improves.

But again this is where I have a problem with all this body calibration and lens calibration.
I have over the past few digital years bought a number of lenses and a colleague has obviously bought for his own use - all these are Canon lenses and range from 500/4L to 15mm fisheye. These lenses are used professionally in activities as diverse as archaeology and motorsport and everything else in between.
These lenses have been used on 1 series bodies in the main (plus a 10D and a 450D) ranging from the original 1D through to the 1Dx and taking in all the 1.3x and FF bodies.
Not one lens (bought new or s/h) has needed to be returned for replacement or sent to Canon for calibration - nor have we thought it necessary to MFA any of them either.
I can also not think of any another Canon user - amateur or professional - who I know has had to have a lens calibrated to make it focus properly.

So you can perhaps see why I am mystified about all this.

Paul, even canon superteles can use some adjustment. Before MFA we used to take what we got. Now folks can tune and get much sharper images. Most pros I know send in their lens and cameras for cleaning, tuning what ever you want to call it. Canon will calibrate stuff as a part of their routine maintenance.

Folks always complain about crappy AF on sigma 30mm f1.4. Mine was super sharp. Then I moved to FF and got 35L. At same time, couple other folks here got 35L and they were having big time AF issues. They had to return or send lens for calibration. It is nothing new.

Someone here picked brand new 70-200mm f2.8 IS II and it having IS issues. Not one but two brand new copies.

Now with sigma glass it happens lot more than canon and it looks like Sigms is trying to fix these issues.

bobbyz wrote in post #15044754
Paul, even canon superteles can use some adjustment. Before MFA we used to take what we got. Now folks can tune and get much sharper images. Most pros I know send in their lens and cameras for cleaning, tuning what ever you want to call it. Canon will calibrate stuff as a part of their routine maintenance.

Folks always complain about crappy AF on sigma 30mm f1.4. Mine was super sharp. Then I moved to FF and got 35L. At same time, couple other folks here got 35L and they were having big time AF issues. They had to return or send lens for calibration. It is nothing new.

Someone here picked brand new 70-200mm f2.8 IS II and it having IS issues. Not one but two brand new copies.

Now with sigma glass it happens lot more than canon and it looks like Sigms is trying to fix these issues.

Just a slight difference between "big time AF issues" and focus calibration (what I am posting about) though.
Not at all the same thing, let's stick to focus issues please.

OK, so which of your sigma lenses were OFF.

bobbyz wrote in post #15044849
OK, so which of your sigma lenses were OFF.

What Sigma lenses?
I don't have any Sigma lenses - not since a late-lamented 18/3.5 which wouldn't work on any Canon DSLR when I went digital back in 2003 - and after all the problems people seem to have with them I would not consider buying any (unless of course Sigma offered a lens I just couldn't do without that Canon didn't make).

PaulB wrote in post #15044725
But again this is where I have a problem with all this body calibration and lens calibration.
I have over the past few digital years bought a number of lenses and a colleague has obviously bought for his own use - all these are Canon lenses and range from 500/4L to 15mm fisheye. These lenses are used professionally in activities as diverse as archaeology and motorsport and everything else in between.
These lenses have been used on 1 series bodies in the main (plus a 10D and a 450D) ranging from the original 1D through to the 1Dx and taking in all the 1.3x and FF bodies.
Not one lens (bought new or s/h) has needed to be returned for replacement or sent to Canon for calibration - nor have we thought it necessary to MFA any of them either.
I can also not think of any another Canon user - amateur or professional - who I know has had to have a lens calibrated to make it focus properly.

So you can perhaps see why I am mystified about all this.

Before there was MFA, the posts were all about why people had to send their cameras and lenses to Canon for adjustments. You may have not had the experiences this way, but we had numerous posts on just POTN about front and back focusing lenses on different bodies long before the 1D3 came out. Back in those days, you either sucked it up and learned to always focus in front or behind subjects to make up for the adjustments, increased your DOF, or you sent all your Canon equipment to Canon for calibration.

The only difference now is that we have more highly dense sensors (with tinier sensels), and people refuse to change their habits of viewing at 100%, so even the slightest missed focus is more noticeable. At least that is my opinion formed from observations as MFA became more prevalent.

TeamSpeed wrote in post #15046316
At least that is my opinion formed from observations as MFA became more prevalent.

So how do you explain the lack of need to use MFA on our cameras which do have it? Think 1D4's and 1Dx's.............
I may very well have another look at MFA'ing my lenses when I get a chance but on a selection I tried previously I found didn't need any; and that includes some lenses going back to the very dawn of EF lenses!

PaulB wrote in post #15048898
So how do you explain the lack of need to use MFA on our cameras which do have it? Think 1D4's and 1Dx's.............
I may very well have another look at MFA'ing my lenses when I get a chance but on a selection I tried previously I found didn't need any; and that includes some lenses going back to the very dawn of EF lenses!

Poor focus results as a product of both the lens and body. One lens could need no MFA on one body, but +15 on another, just like 2 different lenses on one body could do the same thing. One more thing that adds insult to injury, since most lenses are not parfocal (or some other factor/reason), they could very well need different MFA values (or none) at different focal lengths.

When you send in lenses and a camera to Canon, they actually adjust an internal table of values (I read up to 8 points possibly), MFA only gives you 1 value on most of the MFA-enabled bodies, and 2 on the 1DX.

Again, this is based on my experience of having owned at least 15 different MFA bodies, and so many lenses through them, I have lost count. I could be completely in left field too.

bobbyz wrote in post #15044754
Paul, even canon superteles can use some adjustment. Before MFA we used to take what we got. Now folks can tune and get much sharper images. Most pros I know send in their lens and cameras for cleaning, tuning what ever you want to call it. Canon will calibrate stuff as a part of their routine maintenance.

Folks always complain about crappy AF on sigma 30mm f1.4. Mine was super sharp. Then I moved to FF and got 35L. At same time, couple other folks here got 35L and they were having big time AF issues. They had to return or send lens for calibration. It is nothing new.

Someone here picked brand new 70-200mm f2.8 IS II and it having IS issues. Not one but two brand new copies.

Now with sigma glass it happens lot more than canon and it looks like Sigms is trying to fix these issues.

Bobby,

Most people that had issues were probably 1dmk3 owners. That lens didn't play nice with a large batch of 1dmk3's due to the crappy sub mirror assemblies in the body.