ABT SpeedMount EF – a Speedbooster Built Into Your RED Camera

[Jacek Zakowicz]

Will this ever be available in PL mount?

Never say never but probably not. Many PL lenses protrude a lot further that the retrofocal DSLR lenses. There isn't enough space for the SB glass. Not to mention that most PL lenses were designed for S35 format...

[Alex Boothby]

Never say never but probably not. Many PL lenses protrude a lot further that the retrofocal DSLR lenses. There isn't enough space for the SB glass. Not to mention that most PL lenses were designed for S35 format...

Thanks for the reply Jacek. Hmmm....

[Jacek Zakowicz]

Lets put it this way:
If the PL mount on your lens can be switched to EF mount and the lens will clear the mirror (clearing the mirror will assure clearing the SB glass) on a DSLR and cover full frame 24x36mm format it will work. But then again- why would you need PL SB- just put EF mount on your lens and use EF Speed mount....

[Alex Boothby]

Lets put it this way:
If the PL mount on your lens can be switched to EF mount and the lens will clear the mirror on a DSLR and cover full frame 24x36mm format it will work. But then again- why would you need PL SB- just put EF mount on your lens and use EF Speed mount....

Right... I have Sigma Cine primes. I believe they offer factory mount swaps.

[Aaron Lochert]

I'm hoping someone can test the SLR Magic APO Hyperprimes with the SpeedMount and Epic-W.

[David Kellermann]

Yes! Does this mean that the vignette is from image cercle from the lens and not from the speedbooster mount?
So 6k Dragon is doable without vignetting depending the lens!?

Do you have an R3D with a 35mm Art lens or 28mm Otus, wide shot to share?

How do these look with the Canon CN-E primes? They should be full frame capable so they shouldn't vignette, right?

Also, how much do the mount-glass distort sharpness etc?

Not necessarily, as shown in the pictures above. Dragon FF (and I believe Epic W) is 34mm diagonal and speed boosters are designed for S35 - 30-31mm diagonal. Hence the vignetting. Circle of coverage isn't always exact depending on the lens design. Generally longer FF lenses cover more than the required FF 43-44mm circle simply because it's easier to design longer lens with extra coverage that eliminates the extreme corner image degradation. For wides it is more difficult because of the viewing angle the glass size has to "grow" really fast as the circle of coverage increases. For that reason to keep the size and cost low the designers design the wide lenses with just enough coverage for the designated format.
So for longer lenses that actually cover 46-47mm circle for example you may end up not clipping corners on the 34mm diagonal Dragon (Helium) sensor but with wider lenses that barely cover 44mm the speed booster will cut it down to S35 adequate 31mm which clips the corners of the 34mm diagonal coverage.
As far as the IQ theoretically the SB glass should improve the IQ since it is compressing the image to smaller size. In reality due to differences between lenses all you can expect is for the IQ to remain the same.
hope that helps...

That's generally correct but I prefer to think it in the lens terms:
Just "transform" the 50mm F1.8 into 35mm f1.2(0.7 magnificationx50mm and 1 stop gain roughly). Done!!! The lens you are using now (after mounting it on the camera with speed mount) is a 35mm f1.2 lens.

Will this ever be available in PL mount?

Lets put it this way:
If the PL mount on your lens can be switched to EF mount and the lens will clear the mirror (clearing the mirror will assure clearing the SB glass) on a DSLR and cover full frame 24x36mm format it will work. But then again- why would you need PL SB- just put EF mount on your lens and use EF Speed mount....

Thanks Jacek for your perfect replies :) As Jacek explained, the image quality basically stays the same. If you leave the aperture settings on the lens the same, it might get slightly worse on the corners (depending on the lens), since you actually increase the f-stop. But, again, it might even increase the IQ based on the used lens. Brian Caldwell, the designer of the optics used in the SpeedMount, wrote a white paper answering lots of those questions. The same optical element that's used in the Metabones SpeedBooster Ultra is, in a modified version, also used in the SpeedMount, so you can use the widely available SpeedBooster Ultra tests to get an impression of the optical quality of the SpeedMount.

Concerning the "VV" look: using a focal length reducer (in our case with a x0.71 magnification) on a RED Dragon 6k will give you basically the exact same image compared to the same lens at the same T-stop on a RED Dragon VV, only that it's one stop faster (8k Dragon to 6k Draon is x0.75, 8k Dragon to 6k HD Dragon is x0.68 -> Big thank you to Phil Holland for his great PHFX formatCompare tool).

The Sigma 14mm and 135mm cover 8k Helium, the 20mm slightly vignettes at 8k. Didn't had a change to test the other Sigma Cine FF lenses yet. The Tokina VISTA 25mm also covers 8k Helium. I'll post test results with the missing focal lengths and other lenses, such as the Celere, and will update the SpeedMount lens sheet soon.

Here are three frames, shot nearly from the same position with the Canon EF 24-70mm f/2.8L II USM at 70mm f2.8 (Canon 5Dmk3 was slightly lower on the tripod). Both RED cameras and the Canon 5Dmk3 were set to 1/5000 exposure time. The RED frames are cropped to 7k to show the same image circle on the RED with SpeedMount as on the 5Dmk3. I changed the settings in RED Cine-X to better match the Canon look. You can also download the high resolution Canon and R3D file here.

[Jacek Zakowicz]

Thanks Jacek for your perfect replies :)
The Sigma 14mm and 135mm cover 8k Helium

Thank you David!!
Oh the holy grail 14mm f2 turned into 10mm f1.4 S35 lens(!!!!). Now that's a sight to see. David -any chance for an image? drum roll ;-)

[David Kellermann]

Thank you David!!
Oh the holy grail 14mm f2 turned into 10mm f1.4 S35 lens(!!!!). Now that's a sight to see. David -any chance for an image? drum roll ;-)

Here it is. Since it covers VV, it basically has the FoV of a 9mm S35 lens.

[Jacek Zakowicz]

Thank you!!
That looks sublime ;-)

[scott devitte]

I'm hoping someone can test the SLR Magic APO Hyperprimes with the SpeedMount and Epic-W.

I have the APO's and a W and soon a VV. Would love to test them on the Speedmount, David K. can you set up an east coast trial?