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Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)

  
 
tschopp
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p.9 #1 · p.9 #1 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


tsdevine wrote:
From Automate.org:

Stepper

Stepper motors have an internal rotor that is influenced by external magnets. After a winding effect produces energy, the teeth of the rotor turn in fixed steps. Because of their incremental movement, stepper motors offer utility as they can change speed and direction.

Linear Motors

As the name suggests, linear motors can be thought of as an unrolled brushless motor. They are designed using the same underlying magnetic theory, but they operate in an open form. One major benefit of using a linear motor is speed.

Rotary motors (plus rotary-to-linear devices) versus linear motors

When choosing between rotary motors or linear motors, be


I don't know how to "confirm" this beyond a shadow of a doubt though. I'm sure there can be better and worse stepper motors, and better and worse linear motors. But as a category, there must be some tangible benefits of one vs the other, especially if there is a difference in cost. Seems like a more expensive solution would need to yield tangible benefits.

-Tim
...Show more

For the focus motors it seems there are a couple speed terms that get interchanged and confused. The first is how fast the motor can slew from min focus to infinity and back. The second is how fast the control system in the lens can accept focus commands.

From my perspective, not verified by testing, it seems like the 135 GM and 85 DN can slew faster than the 35 GM. But it makes sense the GM lenses will be able to accept focus commands faster because of the tight engineering integration an all sony system can achieve and that being a design goal for the new lenses.

I wrote some control code for a stepper motor, and one nice thing about those is you can specify how many steps you want to move. I don't know if sony has any indexing in their linear motors, so the system knows how far the lens actually moved, or if all feedback is via the image on the sensor. In some ways the image being good is really the only thing that matters and what the lens position is doesn't matter, but it seems easier to calculate where the lens needs to be if you know current location and get some info on needed movement based on the phase detection from the sensor.

When Sony first talked about the linear motors they said the benifit was from extra thrust the motors could provide to accelerate heavier glass.


Apr 27, 2021 at 01:09 PM
ramesesthe2nd
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p.9 #2 · p.9 #2 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


Fred Miranda wrote:
Why? Without seen any images it produces?


I only watched the DPreview video and nothing stood out. Weight, size, AF, bokeh, etc. all look just meh, but you are right. I should wait for the image thread here before declaring it a dud.




Apr 27, 2021 at 01:50 PM
onthebeam
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p.9 #3 · p.9 #3 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


I just finished watching the Gerald Undone video of the new Sigma 1.4. Two thirds of the way through he turns it over to Gordon Laing who also discusses the Sigma 1.4 for several minutes. As much as they are trying to be diplomatic and generous, stating that they are testing a pre-production model, etc., the Sony is the dramatically clear favorite.

Laing's comments are intended to be a synopsis of his own more detailed review which should delve into comparing with the other Sigma 35s. I'll hunt around for that, too.



Apr 27, 2021 at 02:15 PM
nicephore
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p.9 #4 · p.9 #4 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


First, I've read some comments here, then I've viewed Dustin's video.
Note : I haven't viewed Gerald's or Gordon's video by now (*).
In short, I am a bit surprised by the comments (maybe this is simply a kind of "a 35mm fatigue" as so many recent 35mm have been released in such a short time) which we would typically associate with a dull lens.
However, after viewing Dustin's video, it looks like a great lens : 1/ at infinity, wide open, it's slightly better than 35mm GM in the center and worse in the extreme corners ; 2/ very snappy and silent AF ; 3/low-level of distorsion ; 4/ nice bokeh ;
5/ flare resistant; 6/good coma etc...

The only reservation on my side is just comestic : I prefer the look of the GM or the Sigma f2 iSerie.

(*) The fact that it's less good at MFD vs the GM isn't an important point for my usage and, not being a videographer, I don't really care about focus breathing.



Apr 27, 2021 at 03:27 PM
Fboss
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p.9 #5 · p.9 #5 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


I like the samples posted by Dustin. This is making the decision hard for me who was considering the GM until now. Would prefer the lighter GM. But $500 is a big difference for a similar optical quality. (to be confirmed in other reviews)


Apr 27, 2021 at 03:47 PM
Steve Spencer
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p.9 #6 · p.9 #6 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


bjornthun wrote:
Sony addresses the potential issue of tilting through using TWO linear motors on the focus group. As per their own web site.


I'm not talking about the 35 f/1.4 GM, but the general issue of linear motors and I think Sony has addressed this issue in a number of ways and probably the most important is mounts most of their focussing units on rails inside the lens to help prevent tilt. Certainly having two motors--one on either side of the lens moving the same focussing group--would be another strategy to reduce tilt. This is just one way to use two focussing motors, however. You could use two motors with one motor each controlling a different focussing group for example as another use of two motors. That may have advantages as well as probably does as it may speed focussing. I am not at all sure how Sony used the two motors in the Sony 35 f/1.4 GM, and regardless two motors opposite of each other just means pressure is being applied on two points on the lens group instead of one which is likely to be better, but still is not the same things as equal pressure being applied around the circumference of the lens.



Apr 27, 2021 at 04:02 PM
tsdevine
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p.9 #7 · p.9 #7 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


Seems like they generally go in pairs....in both scenarios (single vs multiple focus groups.)



https://www.sony.jp/ichigan/products/SEL35F14GM/



https://www.sony.jp/ichigan/products/SEL50F12GM/feature_1.html

Go to 0:33 and you can see the motors moving the focus groups...





https://www.sony.jp/ichigan/products/SEL135F18GM/feature_1.html

Steve Spencer wrote:
I'm not talking about the 35 f/1.4 GM, but the general issue of linear motors and I think Sony has addressed this issue in a number of ways and probably the most important is mounts most of their focussing units on rails inside the lens to help prevent tilt. Certainly having two motors--one on either side of the lens moving the same focussing group--would be another strategy to reduce tilt. This is just one way to use two focussing motors, however. You could use two motors with one motor each controlling a different focussing group for example as another
...Show more



Edited on Apr 27, 2021 at 04:25 PM · View previous versions



Apr 27, 2021 at 04:13 PM
nhsonyshooter
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p.9 #8 · p.9 #8 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


NJPhotographer wrote:
The leaked Sigma photo on SAR was real after all.


But Cliff Clavin is never wrong



Apr 27, 2021 at 04:16 PM
bjornthun
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p.9 #9 · p.9 #9 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


Steve Spencer wrote:
I'm not talking about the 35 f/1.4 GM, but the general issue of linear motors and I think Sony has addressed this issue in a number of ways and probably the most important is mounts most of their focussing units on rails inside the lens to help prevent tilt. Certainly having two motors--one on either side of the lens moving the same focussing group--would be another strategy to reduce tilt. This is just one way to use two focussing motors, however. You could use two motors with one motor each controlling a different focussing group for example as another
...Show more

The Sony 50/1.2 GM utilizes no less than four linear XD motors, two for each of the two focus groups.



Apr 27, 2021 at 04:20 PM
j4nu
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p.9 #10 · p.9 #10 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


nicephore wrote:
1/ at infinity, wide open, it's slightly better than 35mm GM in the center and worse in the extreme corners ;

Dustin hasn't reviewed the GM yet, has he?



Apr 27, 2021 at 04:30 PM
 


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wind30
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p.9 #11 · p.9 #11 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


just read cameralab review of the sigma f1.4

he repeatedly mentioned that the bigma focuses slightly unreliable on the alpha 1. I don't really feel that for my sigma f1.2 on my A9 or am I not critical enough.

Do you people feel the same way? I thought the bigma AF is pretty good and reliable. For me, it is either the bigma or the gm for 35m..



Apr 27, 2021 at 05:21 PM
Steve Spencer
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p.9 #12 · p.9 #12 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


tsdevine wrote:

Seems like they generally go in pairs....in both scenarios (single vs multiple focus groups.)

https://www.sony.jp/products/picture/original_SEL35F14GM_img_04.jpg


https://www.sony.jp/ichigan/products/SEL35F14GM/

https://www.sony.jp/products/picture/original_SEL50F12GM_XDLM.jpg


https://www.sony.jp/ichigan/products/SEL50F12GM/feature_1.html

Go to 0:33 and you can see the motors moving the focus groups...



https://www.sony.jp/products/picture/original_SEL135F18GM_XDLinearMotor.jpg


https://www.sony.jp/ichigan/products/SEL135F18GM/feature_1.html





There are also quite a few lenses with just one (e.g., 24 f/1.4 GM; 55 f/1.8 ZA; 100 f/2.8 GM), but yes when there are two (14 f/1.8 GM; 20 f/1.8; 35 f/1.8; 400 GM; 600 f/4 GM) or more (50 f/1.2; 135 f/1.8) Sony tends to use pairs, although the 90 f/2.8 G appears to be an exception in which the two motors seem to be used each to power a separate focus group. It does appear in more recent lenses that Sony has moved to design more lenses with linear motors in pairs.

Edited on Apr 27, 2021 at 05:53 PM · View previous versions



Apr 27, 2021 at 05:27 PM
j4nu
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p.9 #13 · p.9 #13 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


wind30 wrote:
just read cameralab review of the sigma f1.4

he repeatedly mentioned that the bigma focuses slightly unreliable on the alpha 1. I don't really feel that for my sigma f1.2 on my A9 or am I not critical enough.

Do you people feel the same way? I thought the bigma AF is pretty good and reliable. For me, it is either the bigma or the gm for 35m..


The Bigma focuses great on A1 imho. It's hard to distinguish it from a native Sony lens in normal use (well, the GM is rather silent while my Bigma makes very faint clicky sound from time to time). The GM seems a tad more repeatable, but not to the point to call the Bigma unreliable...
To be honest, the situation with the reviews is strange , Dustin seems to like the new Sigma a lot, while Gordon seems to think it's really a subpar choice... The difference is that only one of them has tested the GM already .



Apr 27, 2021 at 05:39 PM
Steve Spencer
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p.9 #14 · p.9 #14 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


NJPhotographer wrote:
The leaked Sigma photo on SAR was real after all.


I'm still not sure, because that lens still looks fatter than this lens to me, but hey I only offered my opinion as suggested something that was possible and never claimed anything definitive. It might well have been a copy of this lens and I was fooled by the angle. This lens as I have said all along is noticeably bigger than the 35 f/1.4 GM, but it is also noticeably smaller than the the E mount 35 f/1.4 Art DG. It sits close to halfway in between the two. I would love to see pictures of those three lenses next to one another. I suppose we can see that soon.



Apr 27, 2021 at 05:48 PM
Steve Spencer
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p.9 #15 · p.9 #15 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


nhsonyshooter wrote:
But Cliff Clavin is never wrong


If you are pointing that at me, then you are clearly off base. Maybe like Coach you have taken too many on the old noggin I am often wrong and very likely was this time as well. I just offered a different *possible* interpretation of a prematurely posted picture. Go ahead and make fun of me for doing so. I hope it makes you feel better.



Apr 27, 2021 at 05:51 PM
scalanc2
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p.9 #16 · p.9 #16 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


I really trust in this guy.




Apr 27, 2021 at 06:20 PM
sidaths
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p.9 #17 · p.9 #17 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


I wonder whether Dustin Abbott's views on the Sigma would be different if he had tested the 35GM as well. Either way, the Sigma seems to hold its own IMO, we've just been spoiled by the 35GM.


Apr 27, 2021 at 06:34 PM
Surfnsun
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p.9 #18 · p.9 #18 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


Looks to be a great alternative to the 35GM if you're looking for a better bargain, but still want f/1.4. Well done Sigma.


Apr 27, 2021 at 07:41 PM
Fred Miranda
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p.9 #19 · p.9 #19 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


That was a fast announcement and it's already available for pre-order:
(Sigma is in a hurry!) ;-)

B&H Photo | Adorama ($899)



Apr 27, 2021 at 08:29 PM
f_audet
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p.9 #20 · p.9 #20 · Pre-order: Sigma 35mm f/1.4 DG DN Art ($899)


Gerald Undone has tested both the GM and the new Sigma:



Gordon Laing compared the new SIgma with the GM, the Sigma 35i f/2 and the Sigma 35 f/1.2:





Apr 27, 2021 at 09:37 PM
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