I quite like the look of the sample photos at DPreview. Ghosting, okay, but it wouldn't be a sunstar lens for me; cat's eye bokeh - am not bothered by it. I don't experience the bokeh I've seen so far as distracting or particularly CAish, as opposed to the FE 35 1,8's at 1,8. "Save up a little and get the GM" from Chris but that lens is the equivalent of 2270USD in Sweden. I like the aperture ring, though not the slightly sluggish AF but I wonder where it is (at least more silent) compared to the DSLR version.
Edit. Okay, after seeing some more reviews, the killer is the softness at mfd wide open. Just like Gerald I like to use them like that.
Steve Spencer wrote:
I think we need to understand that performance is more than AF speed and sharpness. If all you care about is AF speed and sharpness the FE 35 f/1.8 would be hard to beat. That lens is very sharp and focusses very fast. If you care about aberrations (especially axial CA) or about the bokeh a lens produces, then you may not like the FE 35 f/1.8. It will be interesting to see what this Sigma 35 f/1.4 does with regard to balance between characteristics. I think the Sigma 35 f/2i is a very balanced lens with very good performance in AF, sharpness, aberration control, and bokeh while it doesn't maximize any of these while leaving poor performance in others (as I believe the FE 35 f/1.8 does). Will the Sigma 35 f/1.4 take the same approach balancing size, AF, sharpness, aberration control, and bokeh? We will have to wait to see....Show more →
Dpreview, Chris and Jordan in their video, say the Sigma 35/1.4 DG DN with stepper motor focuses much slower than the Sony 35/1.4 GM with linear motors.
bjornthun wrote:
Dpreview, Chris and Jordan in their video, say the Sigma 35/1.4 DG DN with stepper motor focuses much slower than the Sony 35/1.4 GM with linear motors.
is that their words or do they just say the Sigma focusses slower than the Sony? Sony clearly made fast focussing a priority, perhaps Sigma did not. Can you link to the DPR video?
Steve Spencer wrote:
is that their words or do they just say the Sigma focusses slower than the Sony? Sony clearly made fast focussing a priority, perhaps Sigma did not. Can you link to the DPR video?
You can easily find it on Dpreview. It’s new today.
Apr 27, 2021 at 10:09 AM
Steve Spencer Offline • • • • • • • Upload & Sell: On
bjornthun wrote:
You can easily find it on Dpreview. It’s new today.
I don't go on Dpreview as a general rule. I do like Chris' and Jordan's reviews, however, and have appreciated them since they started making them for the Camera Store in Calgary. I had hope since you mentioned it you might be able to link to it or at least answer question about it.
If that thing of the AF is true (and there is no reason to doubt Jordan and Chris word on that) it could be the same situation as with the 35 1.4 Art first version vs the Zony 1.4 ZA thing: the former was considerably cheaper and optically as much (if not more) competent than the latter, but the Zony focused faster (and more reliably).
bjornthun wrote:
Dpreview, Chris and Jordan in their video, say the Sigma 35/1.4 DG DN with stepper motor focuses much slower than the Sony 35/1.4 GM with linear motors.
Though i do feel Sony’s linear motor is the best in the biz atm, i think Sigma’s stepper tech is not as refined as Nikon’s.
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 sure to clearly define your goals. The two main considerations should be speed and accuracy, but cost can play a major factor. Linear motors can have substantially greater upfront costs.
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
Apr 27, 2021 at 11:10 AM
Steve Spencer Offline • • • • • • • Upload & Sell: On
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 sure to clearly define your goals. The two main considerations should be speed and accuracy, but cost can play a major factor. Linear motors can have substantially greater upfront costs.
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, one thing more to know about both linear motors and stepper motors is that they are both old technology borrowed for mirrorless because they have 5 features in common: 1) they are very quiet (this is very useful for video); 2) they are very precise (great for focus accuracy) 3) they are small (small is a goal of many mirrorless systems); 4) it is relatively easy to use more than one motor and coordinate these multiple motors; 5) they are fast (obviously speed is a good thing for focus). Stepper motors were used most extensively in the past is clocks and they rotate, which most lenses have done for focussing for decades. Linear motor were used most extensively in speakers before being used in camera lenses, and do not rotate. I suspect, but have no way of knowing that Sony uses linear motors because they have extensive experience with linear motors in speakers (they did make audio equipment for a long time after all). There may not be clear tangible benefits, but rather Sony may be simply using a technology they know well that other companies do not know well.
Best on how good Bigma and 35I are, I was expecting better from Sigma. This is quite underwhelming. Nothing in this lens is inspiring. It kind of reminds me of old Sigma when Sigma was nothing more than a budget option of Canikon.
And Tamron seems to be introducing lenses with linear motors, because Sony owns a stake in Tamron? I don't think Tamron has much experience historically with audio equipment. Fuji has quite a few lenses now with linear motors as well.
Hard to believe that it's just based on familiarity with linear motors....I mean they have moved TO linear motors with lenses, they didn't start there.
I'm not sure how to prove/disprove your theory/hypothesis though. I don't see where rotation buys you much when moving lens groups, linear does seem well suited to that activity (other than needed more motors to get the torque.) So I started looking at broader benefits of the different types, not specific to lenses. In theory, broader based benefits of one type of a motor vs another should be informative in the context of use within lenses.
I mean if we can't trust Sony (or any manufacturer) when they list benefits, and we can't trust anyone reviewing those lenses (under the theory they are just parroting the manufacturers), and we can't compare lenses, because maybe a manufacturer chose to make their stepper based lens slower (and the one using linear motors chose to make it faster.) How can we prove or disprove anything in terms of use within lenses?
Your theory is based on speculation. I'm not saying it's not founded in some sort of logic, but I don't why we should trust you more than the other sources noted.
I guess it's a mystery, since no valid inferences can be made.
Steve Spencer wrote:
Tim, one thing more to know about both linear motors and stepper motors is that they are both old technology borrowed for mirrorless because they have 5 features in common: 1) they are very quiet (this is very useful for video); 2) they are very precise (great for focus accuracy) 3) they are small (small is a goal of many mirrorless systems); 4) it is relatively easy to use more than one motor and coordinate these multiple motors; 5) they are fast (obviously speed is a good thing for focus). Stepper motors were used most extensively in the past is clocks and they rotate, which most lenses have done for focussing for decades. Linear motor were used most extensively in speakers before being used in camera lenses, and do not rotate. I suspect, but have no way of knowing that Sony uses linear motors because they have extensive experience with linear motors in speakers (they did make audio equipment for a long time after all). There may not be clear tangible benefits, but rather Sony may be simply using a technology they know well that other companies do not know well. ...Show more →
ramesesthe2nd wrote:
Best on how good Bigma and 35I are, I was expecting better from Sigma. This is quite underwhelming. Nothing in this lens is inspiring. It kind of reminds me of old Sigma when Sigma was nothing more than a budget option of Canikon.
tsdevine wrote:
And Tamron seems to be introducing lenses with linear motors, because Sony owns a stake in Tamron? I don't think Tamron has much experience historically with audio equipment. Fuji has quite a few lenses now with linear motors as well.
Hard to believe that it's just based on familiarity with linear motors....I mean they have moved TO linear motors with lenses, they didn't start there.
I'm not sure how to prove/disprove your theory/hypothesis though. I don't see where rotation buys you much when moving lens groups, linear does seem well suited to that activity (other than needed more motors to get the torque.) So I started looking at broader benefits of the different types, not specific to lenses. In theory, broader based benefits of one type of a motor vs another should be informative in the context of use within lenses.
I mean if we can't trust Sony (or any manufacturer) when they list benefits, and we can't trust anyone reviewing those lenses (under the theory they are just parroting the manufacturers), and we can't compare lenses, because maybe a manufacturer chose to make their stepper based lens slower (and the one using linear motors chose to make it faster.) How can we prove or disprove anything in terms of use within lenses?
Your theory is based on speculation. I'm not saying it's not founded in some sort of logic, but I don't why we should trust you more than the other sources noted.
I guess it's a mystery, since no valid inferences can be made.
Tim, I am not saying my speculations are anything other than speculations. They certainly aren't theories, but while we are at it let me add one possible downside of linear motor and it is just a possible downside and I have no idea if it has an impact in practice. If you move a focussing group with a linear motor you are moving the lenses along just one side and not the other. Can in time this lead lenses to be tilted/decentered? One advantage of rotating lenses is that you are applying force around the whole rim of the sensor as it rotating this means the force should be equally applied at all points in the circumference. That won't be true with a linear motor and the force being applied has at least the potential to create decentering/tilt. No doubt Sony takes that very much into consideration when designing lenses, but it is an issue that linear motor face that rotating motors don't have to deal with or at least it seems to me that is the case.
Steve Spencer wrote:
Tim, I am not saying my speculations are anything other than speculations. They certainly aren't theories, but while we are at it let me add one possible downside of linear motor and it is just a possible downside and I have no idea if it has an impact in practice. If you move a focussing group with a linear motor you are moving the lenses along just one side and not the other. Can in time this lead lenses to be tilted/decentered? One advantage of rotating lenses is that you are applying force around the whole rim of the sensor as it rotating this means the force should be equally applied at all points in the circumference. That won't be true with a linear motor and the force being applied has at least the potential to create decentering/tilt. No doubt Sony takes that very much into consideration when designing lenses, but it is an issue that linear motor face that rotating motors don't have to deal with or at least it seems to me that is the case. ...Show more →
Steve Spencer wrote:
Tim, I am not saying my speculations are anything other than speculations. They certainly aren't theories, but while we are at it let me add one possible downside of linear motor and it is just a possible downside and I have no idea if it has an impact in practice. If you move a focussing group with a linear motor you are moving the lenses along just one side and not the other. Can in time this lead lenses to be tilted/decentered? One advantage of rotating lenses is that you are applying force around the whole rim of the sensor as it rotating this means the force should be equally applied at all points in the circumference. That won't be true with a linear motor and the force being applied has at least the potential to create decentering/tilt. No doubt Sony takes that very much into consideration when designing lenses, but it is an issue that linear motor face that rotating motors don't have to deal with or at least it seems to me that is the case. ...Show more →
Sony addresses the potential issue of tilting through using TWO linear motors on the focus group. As per their own web site.
