Sigma 18-35mm f1.8 zoom anybody tried it?

JonMcGuffin

@WestEndBoy - Light gathering ability does not change from DX to FX. A 1.8 is a 1.8. The ability of the sensor to hide noise does change but all things equal, a 1.8 DX lens is identical to a 1.8 FX lens in terms of exposure.

To all else,

It's the depth of field that does change, but remember this takes many things into consideration including frame, distance to subject, etc. In the strictest sense, this means a 1.8 DX lens is roughly a 2.7 on FF in terms of how much you DOF you can expect (equivalent wise).

This is neither an advantage or a disadvantage depending on your particular point of view on what you're trying to achieve. In low light, this can actually be an advantage for DX! You get more in focus when shooting at max aperture (most light).

This is SO frequently misunderstood I hope this helps.

Jon

WestEndBoy

Seems reasonable.

JJ_SO

Light gathering abilities can change from lens to lens, caused by different refraction indizes of the used glass. So, f/1.8 remains f/1.8 but if you see the glass as a kind of find mesh, size and number of the meshes define how much light in a given time will reach the sensor's surface.

The DoF, however, will remain the same distance in my opinion if the FL remains the same. DX is just a part of the area of FX but doesn't change a bit of DoF. DoF is nothing digital- meaning it's not like from 3 to 6 foot is everything top sharp and everything outside is bokeh or blurr". It doesn't switch on or off sharpness. That only couild be done with focusstacking.

I tried the 18-35 once on FX, just for fun. But for daily use? I don't see the point.

heartyfisher

I got the 18-35f1.8 for Christmas this year and have been trying it on my full frame body, the vignetting requires some cropping of the sides (at least moving to a 4/3 aspect ratio, though at 5/4 you just get some nice black snips in the corners), but, you still get full 20mm vertical resolution.
It can be used at f1.8 but vignetting is significantly reduced at f2.8, so you're kind of back to square 1 there, it kind of ends up being just a nice odd wide angle lens that also works as the best normal zoom lens ever on crop sensors.
Distortion is an issue as well, I find images look best at 20-22mm (that is, it has barrel distortion at 18mm and pincushion at 24mm, and at 20-22mm there seems to be very little distortion).
I don't have any other wide angle lenses but for my first wide angle lens I am well pleased.

ETA: I should add that the new lens cap is amazing.

Can you post some sample images at FF at various Focal lengths? I am considering this lense for use with my D610 and D7200(when it arrives)

I found what I was looking for in the DPreview review for this lense .. basically at 35mm you can kind of use it in FX. but it not great. however it looks to me that with 1.2 crop mode you could use it from at least 24-35 and i am guessing maybe even from 22-35 ie equivalent of about a 27-42 mm F1.8 zoom. which seems like a useful setup/range for a wide angle /normal zoom with an amazing F1.8 aperture.

tcole1983

I would possibly think about this lens if I sold my 35 f1.8. I still don't see it being a heavy user for me though. In that range I don't really need the F1.8 and I have F2.8 that covers that whole same range. I know not the same, but if I had the funds for this I would probably get the Nikon 10-24.

spraynpray

@tcole1983: I have a mate who has this lens and I have the 17-55 like you. I have to tell you that the difference in the sharpness between the two is not worth buying. If you didn't already have the 17-55, it would be a different story.

Photobug

+1 @spraynpray regarding the sharpness difference.

Hazelnut

Event photographer here, been shooting nightclubs/concerts/fashion shows for the best part of the year as my first paid photography job - so far it's been incredible.
Been using the Sigma 18-35 since January, and it was my 3rd purchased lens, first two being the 18-105 and the 50mm F1.4.
Overall, the lens is tack sharp throughout the range even when shot wide open (Peak sharpness is at F2.8), and it does give out great colors, contrast and detail. Used on the D7000 with an Sb-700, this lens has taken QUITE a beating due to the nature of my work, and it still performs as good as the day i bought it.
The size of it balances great on my camera (with the battery grip), and yes people say it is heavy, but not that much - I find the lens/camera/flash/grip combo easy to handhold for 2-3 hours. YMMV though, this is coming from a young adult that exercises often.
I find 18mm to be wide enough for most uses, but I'd really love a few extra mm's for those occasional big concerts and jam-packed nightclubs, to get proper crowd/group shots. The real problem is the lens only goes to 35mm, which is really quite short when trying to take candids/portraits of people. You have to get really close and usually end up getting noticed or even scaring some people off due to the sheer size of this lens, especially with the hood on. I have combated that by either asking people to pose for candids or use my 50mm, which i always carry in my pocket.
The autofocus speed is good, but not great. I sometimes run into situations where the lens simply won't focus, especially when it's really dark or when my subjects are moving.
This is a very specialized lens, and not one you just pop on your camera and leave it there for most uses. It has become my workhorse, and truly, the F1.8 does help you with more creative applications of DoF once you start experimenting with it. I suggest renting it for a few days before buying, as it may not suit you.