I’ve been reading some articles about Metabones Speed Booster and Zhongyi Lens Turbo II for Fuji X mount. They offer incredible freedom for those (like me) who love to use manual focus lenses on their digital mirrorless cameras. I don’t have a speed booster adapter, yet. But it is on my wish-list.
So, I’ve been thinking about something that Fujifilm could build for all of us and with their innovative spirit, high quality optics and superb manufacture process, this would be a top-selling product, in my humble, non-engineer opinion.
It is a Wide Speed Converter manufactured by Fujifilm, that could give you:
1. One additional stop of light.
2. Full-Frame Field of View on their XF lenses. XF 35mm F2.0 WR would offer you the 35mm FOV in FF terms and F1.4 boosted aperture.
3. Weather Sealing
4. Autofocus on XF lenses.
I guess there could be some technical limitations. I just don’t see how XF 14mm F2.8 or the new XF 8-16mm F2.8 WR could be adapted to work with this kind of wide converter and still offer a viable image. But I see a lot of potential for at least a few of their lenses.
Let’s say that this adapter will only work for XF 23, 35, 50 and 90mm F2.0 WR lenses (because of some technical limitations). Would you buy that? I know I would love to have one! 
PS: This product doesn’t exist. Yet. The image you see is a Photoshop mockup. But with many other existing products, it only started with a dream, a fantasy, a suggestion. If my idea will get credit on Fujirumors, the worldwide largest online community for Fujifilm X and GFX-shooters and non-stop Fujifilm News/Rumors coverage, then we have hopes. It is not the first time when Fujifilm listens to the needs of their customers and surely it won’t be the last.
Fujifilm, if this is not an absurd idea, please manufacture this! Thank you!
All photos and text – © Sebastian Boatca 2017 / www.sebastianboatca.com
Jano
“Fujifilm, if this is not an absurd idea..”
It is, what you’re imagining just isn’t possible.
Henry
This is impossible due to the image circles of apsc lens. No need anyway since we have native f1.4 lenses. And focal reducers cause a loss in sharpness. So forget this!
sebi
Thanks for your feedback!
Layah
Hi Sebastian, you should consider that this is not possible. Focal reducers / speed boosters work by condensing the image circle onto a smaller area. When adapting a full frame lens to aps-c or m4/3, it works because the full frame image circle starts off larger than what’s required. If the lens is designed for aps-c, reducing the image circle means that sections of the sensor will not receive light, or will exhibit extraordinary vignetting.
Using a speed booster with a Canon FD lens like the 50mm ƒ/1.2 is exciting because it would be like Fuji creating a (manual focus) 33mm ƒ/0.85. Ignoring the size of the image circle, turning the Fuji 35mm ƒ/2 into a 23mm ƒ/1.4 will be be very disappointing due to the loss in sharpness. There’s already an excellent 23mm ƒ/1.4 for the Fuji system. To create a focal reducer of high enough quality so that the loss of sharpness isn’t noticeable would be prohibitively expensive compared to simply buying another lens.
sebi
Thank you, Layah for the clear explanation! One can only dream, but it is great to have the technical details, so you know what dreams you can afford. 🙂