I just received my lens a short while ago. I have it with me at work and won’t be able to try it out until I get home. I’m a bit disappointed, however, since there’s a visible FOD (dust maybe) right under the front element. I’m contemplating on returning it and repurchasing from another reputable dealer.
Alpha_Geist wrote:
I just received my lens a short while ago. I have it with me at work and won’t be able to try it out until I get home. I’m a bit disappointed, however, since there’s a visible FOD (dust maybe) right under the front element. I’m contemplating on returning it and repurchasing from another reputable dealer.
If it is a brand new lens and not too much hassle, I would just return it and request a different copy.
Some dust is pretty common and inevitable with lenses sucking in air to focus and zoom. Visible dust really bothers me, but it doesn't affect the IQ of the image most of the time.
ramesesthe2nd wrote:
If it is a brand new lens and not too much hassle, I would just return it and request a different copy.
Some dust is pretty common and inevitable with lenses sucking in air to focus and zoom. Visible dust really bothers me, but it doesn't affect the IQ of the image most of the time.
I ended up submitting a Refund request. Since the elements are fairly small, the dust will have an effect in certain instances. If this were a larger lens, then perhaps the dust won’t have any effect...but larger lenses tend to cost a lot more and I would expect much cleaner internals. I already have it boxed and ready to go back via FedEx on Friday.
One thing that really stood out was how well the lens felt in hand (solid) and how diminutive it is. I was expecting it to be even larger than what I saw in pictures of the lens. I’ll have my replacement from Adorama this time next week.
genji wrote:
Yet another disappointment for the 28mm contingent.
I sold my Sony 28mm F2, I never really liked that lens apart from size, and went for the 24mm GM, and crop if needed.
With the trio of small and light Sigma with aperture rings being released soon, I keep coming back to Sigma’s “neglect” of this 45mm which gives me pause on buying more of these DN lenses.
Does anyone know if the Sigma 45mm will never get a firmware update specifically targeting the AFS-C issue because in Sigma’s mind their lens is already “perfect” and that what AFS-C issues is “by design?”
It’s bad enough to have one lens that I can’t use reliably, so I won’t be touching those other ones unless people report that Sigma has “finally solved” those issues on those lenses.
FMTopFan wrote:
With the trio of small and light Sigma with aperture rings being released soon, I keep coming back to Sigma’s “neglect” of this 45mm which gives me pause on buying more of these DN lenses.
Does anyone know if the Sigma 45mm will never get a firmware update specifically targeting the AFS-C issue because in Sigma’s mind their lens is already “perfect” and that what AFS-C issues is “by design?”
It’s bad enough to have one lens that I can’t use reliably, so I won’t be touching those other ones unless people report that Sigma has “finally solved” those issues on those lenses. ...Show more →
The consensus seems to be that it’s not an “issue” on this particular lens, it’s an inevitable byproduct of the high SA look at close distances and wide apertures that is what people like bout this lens. SA and PDAF don’t play well together. You find something similar with vintage lenses auto focussing on TAP: the more the SA, the less the reliable PDAF.
DavidBM wrote:
The consensus seems to be that it’s not an “issue” on this particular lens, it’s an inevitable byproduct of the high SA look at close distances and wide apertures that is what people like bout this lens. SA and PDAF don’t play well together. You find something similar with vintage lenses auto focussing on TAP: the more the SA, the less the reliable PDAF.
I still don't think that's the whole story here, because whenever I stop down the Sigma 45mm to for example F4 AF-C is still unreliable. At F4 the SA isn't an issue anymore. The camera focuses at this aperture when using AF-C.
So in my opinion the lens just isn't that good for AF-C shooting in general and not because of the SA alone.
BTW: my Sigma 85 DG DN (which doesn't have any SA at all) also isn't that great when shooting AF-C.
The strange thing is that both the 45 and 85 focus super fast and spot on in AF-S. Also: the first shot of a burst (using AF-C) is spot on most of the time.
So IMHO the Sigma algorithm just isn't that great (yet?) at tracking compared to Sony lenses.
Jochenb wrote:
I still don't think that's the whole story here, because whenever I stop down the Sigma 45mm to for example F4 AF-C is still unreliable. At F4 the SA isn't an issue anymore. The camera focuses at this aperture when using AF-C.
So in my opinion the lens just isn't that good for AF-C shooting in general and not because of the SA alone.
BTW: my Sigma 85 DG DN (which doesn't have any SA at all) also isn't that great when shooting AF-C.
The strange thing is that both the 45 and 85 focus super fast and spot on in AF-S. Also: the first shot of a burst (using AF-C) is spot on most of the time.
So IMHO the Sigma algorithm just isn't that great (yet?) at tracking compared to Sony lenses.
Sony cameras are notoriously lens specific and body specific in terms of how they focus when you stop down.
I don't know what body you have, but it's perfectly possible that it's focussing at f2.8 when you stop down to f4 (ie behaving like an auto aperture DSLR lens). This definitely happens depending on body, lens, and various body settings. Of course if it *is* focussing stopped down, that too isn't great.
I've had very reliable results with eye AF (which is PDAF) in continuous mode on the 85 DG DN; but I guess there could be a body - lens combination issue.
DavidBM wrote:
Sony cameras are notoriously lens specific and body specific in terms of how they focus when you stop down.
I don't know what body you have, but it's perfectly possible that it's focussing at f2.8 when you stop down to f4 (ie behaving like an auto aperture DSLR lens). This definitely happens depending on body, lens, and various body settings. Of course if it *is* focussing stopped down, that too isn't great.
I've had very reliable results with eye AF (which is PDAF) in continuous mode on the 85 DG DN; but I guess there could be a body - lens combination issue....Show more →
I also don't have any issues with AFC on 85 dg dn, unless we're talking strictly about tracking fast erratic movement, but then I think this 85mm f1.4 was not designed with that as the main goal...
j4nu wrote:
I also don't have any issues with AFC on 85 dg dn, unless we're talking strictly about tracking fast erratic movement, but then I think this 85mm f1.4 was not designed with that as the main goal...
Right, and the 85 GM, for instance, lovely though it is, is also not good at tracking fast erratic movement
DavidBM wrote:
Right, and the 85 GM, for instance, lovely though it is, is also not good at tracking fast erratic movement
That's not a fair comparison at all, because of the super slow AF motor in the GM.
The one in the 85 DG DN is very fast (that's why the first shots in an AF-C burst are spot on most of the time), but in tracking it's just not reliable.
For slowly predictable moving subjects it's all fine, anything faster/erratic not.
The FE 85/1.8 is MUCH better at this (on my A9) than the Sigma 85 DG DN. The exact same goes for the 100-400 DG DN compared to the Sony 100-400.
All this "it's not designed for that" talk is just too easy. Sigma's AF algorithm just isn't at the same level as Sony's own native lenses. That's my clear conclusion on both my A9 and A7RIII.
Other than that the Sigma DG DN line are lovely lenses for a great price.
Jochenb wrote:
That's not a fair comparison at all, because of the super slow AF motor in the GM.
The one in the 85 DG DN is very fast (that's why the first shots in an AF-C burst are spot on most of the time), but in tracking it's just not reliable.
For slowly predictable moving subjects it's all fine, anything faster/erratic not.
The FE 85/1.8 is MUCH better at this (on my A9) than the Sigma 85 DG DN. The exact same goes for the 100-400 DG DN compared to the Sony 100-400.
All this "it's not designed for that" talk is just too easy. Sigma's AF algorithm just isn't at the same level as Sony's own native lenses. That's my clear conclusion on both my A9 and A7RIII.
Other than that the Sigma DG DN line are lovely lenses for a great price.
Yeah, I agree if you mean strictly tracking preformance, Sigma is definitely not the best. It wouldn't make me call it "isn't that great when shooting AF-C" though, but to each his own I guess .
What I meant by my comment was, that in my view 1.4 lenses are not tailored for shooting action, but I may be wrong of course...
Dec 01, 2020 at 07:45 AM
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Jochenb wrote:
That's not a fair comparison at all, because of the super slow AF motor in the GM.
The one in the 85 DG DN is very fast (that's why the first shots in an AF-C burst are spot on most of the time), but in tracking it's just not reliable.
For slowly predictable moving subjects it's all fine, anything faster/erratic not.
The FE 85/1.8 is MUCH better at this (on my A9) than the Sigma 85 DG DN. The exact same goes for the 100-400 DG DN compared to the Sony 100-400.
All this "it's not designed for that" talk is just too easy. Sigma's AF algorithm just isn't at the same level as Sony's own native lenses. That's my clear conclusion on both my A9 and A7RIII.
Other than that the Sigma DG DN line are lovely lenses for a great price.
Is the Sigma 85 f/1.4 DG DN worse than the FE 85 f/1.8 at the same apertures? One would expect worse AF performance especially for fast erratically moving subjects with a wider aperture (i.e., narrower depth of field). If the Sigma really is doing worse, then I wonder whether Sony really has fully open mount protocols, or if they are holding back and only providing third parties with some, but not all, the AF mount protocols for E mount. If Sony truly has an open mount, then they should have no inherent AF advantage for their lenses.
Faster apertures, mean more glass, and need for more powerful AF motors to drive it and make all the nuanced tracking movements. Pretty substantial difference between f1.4 and f1.8. Sigma weighs 22oz, 85GM weighs 28oz, FE 85 1.8 weighs 13oz.
I think the "design purpose" of the lens definitely matters when it comes to AF. i.e. 135GM also involves a lot of glass, but has a a beastly AF motor(s). It'd be possible to employ similar designs to the like of the Simga 85 and 85GM, but it doesn't come without a cost...literal cost, and also size.
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