Sigma 35/85 1.4 DG DN vs. Summicron SL35/75/90 - AF with Sigma really faster?

[FrankX]

Advertisement (gone after registration)

I am currently considering going all Leica photographing weddings. Currently, I have no Leica AF lens, however, I am thinking about buying the Summicron-SL 35 and 75 or 90 as a two lens setup.

I currently own the Sigma 85 1.4. Whilst the overall image quality seems to be very good (cannot compare to SL 75/90), the AF seems to be quite slow. I don’t have any experience with the new Sigma 35 1.4 besides a few shots in a shop. The slow AF performance of the 85 would be one of my main reasons to change to the Leica lenses.

Yesterday I discovered an article written by Jay Cassario (a Leica ambassador) stating that he tested the Leica lenses against Sigma‘s in real wedding environments and came to the conclusion that the Sigma lenses were even slightly faster!  You can find the article on the Sigma Blog. 

This was a big surprise for me considering my own experience with the 85 1.4 DN lens (driven by a single stepping motor by the way). Thus my question: Has anyone here experience with both (the Sigma and the Leica lenses mentioned) and can acknowledge his results (or explain in which situations the Sigma might be even slightly faster)? 

I appreciate all your comments! Really… Maybe Jay is also here in the LUF? 😉
 

Edited November 5, 2021 by FrankX

[Advertisement]

The Leica Q3 is available for pre-order at B&H Photo Video and Adorama

[sillbeers15]

My brief experience handling the Sigma 85mm F1.4 DG DN did not made me feel that the Sigma lens is any slower than my SL75 in acquiring AF. I did not feel it to be any faster than my SL75. However the compact size and light weight of the Sigma lens makes it logical to respond fast in AF (provided the linear motor is not slower).

[BernardC]

2 hours ago, FrankX said:

I currently own the Sigma 85 1.4. Whilst the overall image quality seems to be very good (cannot compare to SL 75/90), the AF seems to be quite slow.

Do you have the new 85 "DG DN," or the previous "DG HSM"?

[FrankX]

vor 1 Stunde schrieb BernardC:

Do you have the new 85 "DG DN," or the previous "DG HSM"?

The new DG DN! The only comparison I have on the SL2 is the Sigma 24-70 which is way faster!

Focusing at 5 m distance and then at about 1 m:

85 mm at 1.4: about 1 s

Zoom 70 mm at 2.8: about 0.5 s

Light level: ISO 3200, 1/160s, f/1.4

Edited November 5, 2021 by FrankX

[FrankX]

vor 3 Stunden schrieb sillbeers15:

My brief experience handling the Sigma 85mm F1.4 DG DN did not made me feel that the Sigma lens is any slower than my SL75 in acquiring AF. I did not feel it to be any faster than my SL75. However the compact size and light weight of the Sigma lens makes it logical to respond fast in AF (provided the linear motor is not slower).

Thanks for the comment.

BTW: As far as I know, the Summicrons all have two linear motors whereas the 35/85 DG DN use only a single stepping motor.

[Photoworks]

the 35mm  1.4 is a good lens, and yes a little slower to focus than the Summicron SL, especially when the light is dimmer.

Edited November 5, 2021 by Photoworks

[RBB]

Advertisement (gone after registration)

Just compared (not scientific) the Sigma 85mm f/1.4 DN DG and the SL75mm Summicron. Looks like the SL75 focus just a little bit fasterr, but not by much, both of them are fast enough for me.

[Speeding]

A few factors here to consider.  Important to distinguish between time to acquire focus (speed) and accuracy/consistency of focus.  I find the L-mount Leica lenses to be slightly faster to reach the focal point than the Sigma's but the real difference is in accuracy and consistency.  My Sigma primes tend to hunt and miss more than the Leica's (and Panasonic's).  Sometimes stretching the full range from near to far and back again before giving up.  It can be very frustrating with PJ and documentary work where I don't get second chances.  I tend to shoot people who are moving about in C-AF so it is expected to have a bit of back/forth movement with CDAF systems but the Sigma's seem to exaggerate the hunt more which can be a bit distracting.   If you use S-AF for your work I doubt you will be disappointed in the Sigma's.  The other thing to consider with some Sigma Art's is some tend to give me more LoCa than Leica counterparts but this might be due to the different apertures (1.2 or 1.4 on Sigma's vs 2.0 on Summicron SL's).   

On E-mount cameras with PDAF the Sigma's tend to be a little more consistent but still not as reliable as GM lenses so some of this is to blame on lack of PDAF in most L-mount bodies.

Ultimately I use L-mount lenses from all 3 manufacturers but the Summicron's really are special.  They are the first lenses I reach for.  Never fail to impress me.  Many go with the 35/75 approach and are quite happy with that combo.

[sillbeers15]

33 minutes ago, Speeding said:

A few factors here to consider.  Important to distinguish between time to acquire focus (speed) and accuracy/consistency of focus.  I find the L-mount Leica lenses to be slightly faster to reach the focal point than the Sigma's but the real difference is in accuracy and consistency.  My Sigma primes tend to hunt and miss more than the Leica's (and Panasonic's).  Sometimes stretching the full range from near to far and back again before giving up.  It can be very frustrating with PJ and documentary work where I don't get second chances.  I tend to shoot people who are moving about in C-AF so it is expected to have a bit of back/forth movement with CDAF systems but the Sigma's seem to exaggerate the hunt more which can be a bit distracting.   If you use S-AF for your work I doubt you will be disappointed in the Sigma's.  The other thing to consider with some Sigma Art's is some tend to give me more LoCa than Leica counterparts but this might be due to the different apertures (1.2 or 1.4 on Sigma's vs 2.0 on Summicron SL's).   

On E-mount cameras with PDAF the Sigma's tend to be a little more consistent but still not as reliable as GM lenses so some of this is to blame on lack of PDAF in most L-mount bodies.

Ultimately I use L-mount lenses from all 3 manufacturers but the Summicron's really are special.  They are the first lenses I reach for.  Never fail to impress me.  Many go with the 35/75 approach and are quite happy with that combo.

Great observation you've shared.

The only Sigma lens I have is the 150-600mm. Comparing to my SL90-280, the Sigma lens hunts quite a bit more on AFC application. My thoughts were that the focal length is longer compared to my SL90-280 so perhaps that should be the reason. Now matching to your experience on shorter focal length lenses comparison, it is likely that the data points provided by Sigma lenses to the L-mount bodies (DFD on CDAF) could be less compared to Leica SL lenses that results in the additional focus hunting.