Anyone use the Ziess ZF 25mm or 21mm?

[benhuddleston]

I just got the 28mm Zeiss ZF, and I wish it were slightly wider. I'm thinking about swapping it for the 25mm, even at the expense of another stop of light. Maybe I could even be coerced into going as wide as the 21mm....

[Kholi]

If you actually get a 21/2.8 I'll be jealous as hell

That wide is infamous.

even then, I'd suggest getting a converted 17-35 Zeiss Contax N. at least you're covered from 17 and up.

[Dennis Wood]

On an adapter, don't bother with a prime under 28mm. The Brevis is likely one of the best adapters in the world in terms of FOV and light efficiency with wide angle lenses...and we don't recommend wider than the 28mm f2 in terms of prime lenses. Zoom lenses are a different story as (at least on our adapter) as they tend to perform better with respect to edge to edge illumination at a given f-stop. I've got a 28-200mm cheap test zoom at f3.5 that is nearly perfect edge to edge at f3.5. I'd never be able to recommend a 28mm prime at f3.5 though as the edge falloff would require zooming in, effectively negating your wide angle FOV. The f2.8 constant aperture Canon and Nikon zooms perform amazingly well at 17-35mm so either of these would be a better investment in terms of wide angle coverage than primes in this range. Above 28mm, there's no question that in terms of bokeh and organic punchy images, nothing we've tested touches the Zeiss ZF glass.

[Kholi]

Sorry Dennis, but if the Zeiss ZF 21/2.8 is a direct copy of the Contax Zeiss 21/2.8, those zooms can't touch it.

But, good point is what adapter OP is using. I've used a few primes in excess of 28mm on the Ultimate without experiencing too much edge loss, dunno about other adapters though.

[Andrea189]

On an adapter, don't bother with a prime under 28mm. The Brevis is likely one of the best adapters in the world in terms of FOV and light efficiency with wide angle lenses....

Sorry to say Dennis but I used a Nikon 20mm f2.8 on the Cinemek G35, with a polarizer and an nd filter, it did produce some really beautiful exterior shots that were edited into a 5' short promo with a budget of 20,000 euros. The director, the producer, the client and myself were really happy about the quality of the image.

[Dennis Wood]

I'm not saying that you can't get a great image with those lenses, particularly if you zoom in to eliminate edge fall-off. What I am saying is that if you want to use a 20mm f2.8 lens and achieve the full 36mm wide FOV, you will find this virtually impossible regardless of adapter! If you do zoom in...that's great, but you effectively lose the FOV you were looking for with the wide angle lens.

Many folks are zooming into the 35mm adapter's projected image well into the 36mm SLR format width and simply don't realize it with spinner adapters as there's no frame gate in these to compare to. From what I've seen of wide angle footage posted, I'd estimate that this loss of FOV is as much as 30% with a few of the adapters. We've also noted a few of the achromat focal lengths in use on other adapters which corroborate that statement. With the Brevis, there is a definite frame there and it's about 40mm wide....so if you do have to zoom in more than usual, you have a pretty good idea of your effective usable frame. FOV is something we're pretty sticky about which is why you'll never see us making claims of zero vignetting or fall-off. Every lens on the planet has inherent (and varying) fall off so when we recommend a lens for adapter use, it must maintain a usable 36mm wide image frame. That's our criteria.

[Gogu]

Dennis,

On my Nikon 17-35 at 17mm (wide open i think) I could see some edge softness.
I also used a 14mm Ultra Prime and It didn't seem to exhibit this softness. Is it because of the lens or the adapter ? (ultimate)

Also when using cine lenses I noticed that on the wide ones you get a different shape of the projected image. The wider the lens the square frame of the adapter becomes rounder on the edges...meaning you have to zoom more through all that vignneting. Why is that ?