sigma 17-50mm 2.8 vs panasonic 12-35mm 2.8

Hi.

I can`t decide between the "Sigma 17-50mm 2.8 + Blackmagic Speedbooster" and the "Panasonic 12-35mm f.2.8"
I was wondering if someone had any experience with both lens and could give me some advice.

In Theory with the Sigma i would get around 10-29mm with Speedbooster (0.58 wider).
Its a bit wider then the Panasonic but not a huge difference i guess.

If I am right the Sigma Image Stabilization and autofocus should work with the "Bmpcc Speedbooster Canon mount" as its an active mount. Is that correct?

The extra Speedbooster f-stop would give me around f.2.0 if that is correct as well?

From what I understood is that even with the extra f-stop i won`t get a shallower depth of field but more light in low light condition.
So basically when shooting Panasonic in f2.8 and Sigma f2.0(extra Speedbooster f-stop), i would get the same depth of field? So with the speedboost I won`t profit from a shallower depth of field at all?

Also, i have heard at a lower focal length gh4 or gh5 user will get a strong vignette effect with the sigma lens. Does anyone know if that will happen with the bmpcc as well?



Thanks
Jan

The Sigma is a APS-C only lens.
It depends on the camera you use if a SpeedBooster does work here.

Oh I am sorry. It would be for the blackmagic pocket and I thought about using the bmpcc speedbooster.

That lens and SB combo would work just fine, same as using the Sigma 18-35, and I prefer the IQ of the 17-50 over the overly sharp 18-35 (which does not play well with thenSB/Pocket Camera). The advantage of the 17-50 is you get a 10m to 50mm by using both a SB and a straight MFT adapter (no optics). The biggest advantage here is, if yiu trade up to a larger camera like the Urs Mini, yiu can still use this lens.

The advantage of Panny 12-35 is it is smaller and lighter than the 17-50, but has less covers on the long end. Being a native MFT lens, it will have IS (an advantage when handholding), smaller and easier to use. But it will be a stop slower at f/2.8, than the 17-50 with SB combo. I find 12mm is fair,y wide on the Pocket camera, anything wider is in the Ultra Wide category. However, neither of these zooms are true parfocal, and require refocusing when zoomed.

If you need the longer reach of the 17-50, and 12mm is wide enough, I would suggest looking st the new Panny Leica 12-60 f/2.8 Zoom, while not as fast as the 17-50, it is still lighter, and does not need the Speed Booster adapter. The PL 12-60 is parfocal, has great IS for hand held shooting, longer on the long end, and is a good size for shooting on both the Pocket or Micro Cameras. It’s disadvantage is it is a little slower, depending on the focal length, but has a steppless iris (no jumps in f/stop changes) and was designed for video work, unlike the other still camera zooms.
Cheers

Hi Danny.

Thank you very much for enlighten me
I thought about the Pany 12-60mm which is quite tempting indeed. But from what i read, up to 23mm it turns basically into a f3.5 to f4.0 and i am not sure if that`s worth it.

Yes, the ramping down the f/stop is the down side, but when shooting outdoors, I am normally at around f/4.5 somit is not an issue. Indoors, I am normally staying wider at 12-20mm, and have the extra stop where I need it. Unfortunately, no one lens is perfect, each one has it advantages and compromises.

I have the PL Prime set for low light shooting, and the new zoom matches their IQ very nicely. But the biggest advantage when Hand holding the camera, is the IS at all focal lengths. The Primes do not have IS on the 12,15 or 25mm lenses, and when you get to 25mm, you really need some form of stabilization, at least I do.
Cheers

Haha yep, there is always a drawback. This lens has not stabilization, the other one could just have at least one more f-stop and another one is missing just few more millimeter focal length.
Then i thought speedbooster will solve quite a few problems until i noticed the extra f-stop doesn`t give you shallower depth of field....it never ends

But thanks again for your help, what you are saying definitely makes sense to me and maybe i should have a closer look at the panny 12-60mm again.

Jan

Yes Jan, I went the larger lens, Speed Booster route, as I had some Zeiss ZF lenses. Considered getting the Sigma 18-35 in a Nikon Mount, but then I picked up the 4/3rds Panny Leica 14-50 f/2.8, and liked the IQ better (kens is not parfocal either), and it has IS, and was a/2.8-3.5: so ramping was on only stop. This became out go to lens for green screen PSA spots I was producing on a AF100.

Then I got the Oly F/T 14-35 f/2.0 for low light work, this lens is great, excellent I.Q, real manual focus in addition to AF, IS and was Parfocal, with no ramping. This replaced the PL 14-50 Zoom. Only down side, this is a large, heavy lens, with a 77mm front ring. So was only used on the AF100, mounting a Pocket camera to it, was like putting a camera on a lens!

When I got mt Pocket camera, I used the PL zoom, as it was a little smaller and half the weight. But, still large, so I went prime lens route, getting the 25 and 45mm PL Primes, and later the 15mm, which I also use on a Oly PenF Camera. These are nice small lenses and fit the small compact camera concept better
When the PL 12-56 came out, this became the best compromise Zoom, which solved the issues of the previous F/T zooms, being smaller and lighter.
Cheers

Piggybacking on this to ask whether there's any possibility that there will one day be an adapter to allow Sony E-mount lenses to be used on MFT cameras? I've read up on it a bit and it doesn't seem possible, but it's frustrating because I started with Sony and have a couple of really nice Zeiss lenses that I would love to be able to use on the Pocket camera.

Sorry, this is never going to happen. It would be like trying to put a MFT lens on a Canon EF, or Nikon F mount, the Sony E Mount has a shorter FFD than MFT, so a E lens would never get Inf. focus if you did manage an adapter. They are close, but not close enough, FFD are very precise. The second issue is Sony is not going to license an E Mount on any camera that is not Sony.

But, if you had a camera with a very short FFD, and it’s own universal mount (similar to the E Mount) that could accept a E Mount adapter and give the correct FFD, then this would work, but you would need to reverse engineer the Sony protocols to get a E lens electronics to work, and run the risk of being sued by Sony for violating its patents.
Cheers

Omg. Good that you went this route already for me

When the PL 12-50 came out, this became the best compromise Zoom, which solved the issues of the previous F/T zooms, being smaller and lighter.

I guess you talking about the Panasonic 12-60mm?

Thanks again, very helpful information

Yes Jan, I meant the new 12-60mm. Too many zoom lenses running around my head!
Cheers

Hi.

I can`t decide between the "Sigma 17-50mm 2.8 + Blackmagic Speedbooster" and the "Panasonic 12-35mm f.2.8"
I was wondering if someone had any experience with both lens and could give me some advice.

In Theory with the Sigma i would get around 10-29mm with Speedbooster (0.58 wider).
Its a bit wider then the Panasonic but not a huge difference i guess.

If I am right the Sigma Image Stabilization and autofocus should work with the "Bmpcc Speedbooster Canon mount" as its an active mount. Is that correct?

The extra Speedbooster f-stop would give me around f.2.0 if that is correct as well?

From what I understood is that even with the extra f-stop i won`t get a shallower depth of field but more light in low light condition.
So basically when shooting Panasonic in f2.8 and Sigma f2.0(extra Speedbooster f-stop), i would get the same depth of field? So with the speedboost I won`t profit from a shallower depth of field at all?

Also, i have heard at a lower focal length gh4 or gh5 user will get a strong vignette effect with the sigma lens. Does anyone know if that will happen with the bmpcc as well?

For any given framing, when both are wide open, it will be shallower depth of field with the Sigma + focal reducer combo than with the Panasonic zoom lens.