If you use wide angle lenses, Sony's newest release in their full frame, mirrorless range for E-mount might be interesting to you. It certainly has its perks, but it's not without drawbacks.
Sony's new ultra-wide FE 12-24mm f/2.8 GM lens is catching a lot of photographers' attentions. If you've never shot at 12mm on a full frame body, you might be surprised just how wide it really is. I had to use a 12mm zoom lens similar to this on a job some years back, albeit on a Canon body, and once you get below 20mm, every extra millimeter you zoom out is substantial. For landscape, cityscape, and astrophotographers, Sony's lens that is releasing soon might be exactly what you're after. It does however, come with some drawbacks.
One of the key issues is shared with the lens I used that had a widest focal length of 12mm: a fixed lens hood to stop flaring and protect the inevitably bulbous front element. This prohibits the lens from using most filters (although if I remember correctly, there were systems in place for my lens which you circumnavigate this problem to some degree.) However, there is space at the back of the lens for a slide-in filter.
The bigger issue for me is the price. B&H currently lists this lens at $3,000 which is a staggering amount of money for a full frame lens. Yes, it's a fixed barrel length, f/2.8 through the focal ranges, and comes with the build quality we've come to enjoy with G Master lenses, but that's a lot of cheddar to drop on one lens. For $500 more, you can buy the incredible Sony a7R IV with an accessories kit! For me, I consider myself priced out of ever using this lens, which is a shame because it does seem like great glass.
What do you think of it?
I have the 12-24/4 and love it. It seems like you're asking if a 12mm makes sense - for me, absolutely. Huge upgrade coming from a 16-35/4. There are situations where shooting at 16mm makes you feel like you're too fat for the room.
That said, I don't make a lot of money doing freelance real estate so the f/2.8 isn't even a consideration. I suppose the story would be a little different for a high end guy who makes bank and already has his tilt/shifts.
At 3k? Absolutely f'ing not. Sony just pushed anyone considering it to the Sigma 14-24 f/2.8. It should have matched the 16-35 price point at minimum to garner any interest. They already have the f/4 G master for $1200 less. I honestly don't know who they are marketing this lens too. Some of us have paid a premium for one or two Sony lenses we really wanted but I don't think this lens is going to be one of them, not at that price point.
There are two people who are going to get this lens and they are named Dustin and Jared. I'm sure it's optically great. Just not $1600 great. Maybe they thought this would push people to buy the f/4. I'm sure it will move a few units. Although they forgot Sigmas was f/2.8 and cheaper than the f/4
14-24 is not 12-24 by a longshot - this is why Sigma also makes both 12-24/4 and 14-24/2.8 in the same mounts.
Pretty sure this lens was mostly made just to one-up Canon's 11-24.
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For me this a dream lens I have prayed for!!! That said If you have used the f/4 model then the use is already firmly placed for 12mm. I started astro MW in early 2015 after finding that my new A7S is perfect for night work first used the inexpensive Rokinon 14mm f/2.8. Now only a camera can capture the MW with a long exposure for it is like a whisper of white cloud of stars on a clear night but when you see it on your camera LCD you see hummingbird like colors in the Galactic center and rainbow colors of high level gases. In post everything will just pop out like a 3D stereo picture. That was 2015 and only Sony A7S with low noise to way above Canon/ Nikons limits of 6400. The 1635 f/4 is superb at no coma but to get to 12mm the 1018 f/4 at 12mm in Full Frame was my cats meow til the 1224 f/4. But first this needs to be said at f/4 on a A7S/A7iii you have night vision where you have to reduce exposure before most think it was PS'ed, I have had to show my images on the camera before I was believed. Night work with the f/4 is superb BUT many have paid a lot f/1.8 and f/2.8 lenses all between 12-24 and bags are full of them. After August many will be on the market as used. This lens will replace about 9 expensive lenses including the 1635 2.8 (24mm in APS-C 36mm). And not just for the many Pro MW people but night and dusk also with the indoor museum where tripods are not allowed. But not a "GET IT ALL IN" lens but with an eye on close subjects is needed. Yes $3K is up there but look at the young new photographer will not have to get fast and wide lenses everytime new one comes out in prime mm's, that is the value of the $ over the long run with this lens. Night is 2.8 (or prime 1.4) and day is f/11. Like when is the last moment of a sunset, after the sun is down OR during the blue hour when even the human eye can see the color! Have you not been out in the morning for a sunrise 2 hours before but that first glow of light with stars and in post brightened to where the driftwood tree is not a silhouette but is seen like the eye sees it with that faint color on the horizon and white puffy clouds above even the MW is visible and colorful even with a crescent moon. This lens is for those who roam at night like an owl with those big eyes where daytrippers have no idea of the hidden colors they miss while they sleep till 9 or 10.
Look even all that "FAST" glass has to be used at 2 or 2.8 for the physics of light through the edge of a lens is slower than that going through the center, it is how your famous bokeh/blur is made BUT at night things are somewhat reversed with the light through the center is faster and only little softness on the edges or vignetting that with correction in post makes for clean edge to edge sharp image. And this lens has it ALL pinpoint stars and coma's almost not there with no distortions that were seen in all lenses of the past.
You want low cost but have no knowledge of what is being overcome, Sony could have sold for WAY more but it's base photographers are it's bread and butter not so much the pro's with deep pockets - That is why I went Sony in 2014 for I am from the film days and lens buying then was just as painful on the pocket as now. Photograph within your budget PLEASE but remember Sony will make your dream a reality when the pennies are there!!!!