I currently own a Panasonic GH5 and I’m also considering another MFT camera the Z Cam E2 and thought both of these cameras would be great with a Sigma 18-35mm f1.8, so I’m in the market for a Metabones Speed Booster and I’m not sure which one I should get the Ultra or the older XL version, my concern is which one will cover the sensors used in both the GH5 and the Z Cam E2……………. when the Sigma 18-35mm lens is wide open at 18mm?
GH5 Best Metabones for the GH5/Sigma 18-35 f1.8 Lens
- Thread starter Vardalos
- Start date
cyvideo
Veteran
I don't know but this might be worth a read. With comments like the following I would suggest the Speed Booster Ultra 0.71x.
"The MTF curve in Figure 3 indicates that the Speed Booster ULTRA m43 has truly phenomenal performance at f/1.0, which is the output aperture you will get when the master lens is set to f/1.4. Extremely low levels of aberration in the Speed Booster ULTRA m43 combined with the aberration-reducing tendency inherent in focal reducers means that even extremely high performing lenses such as the renowned Zeiss Otus series can actually be improved! This is illustrated in the pair of measured MTF graphs below in Figure 7."
"Measured MTF Using a 55mm Zeiss Otus as the Master Lens:
The 55mm f/1.4 Zeiss Otus is widely recognized as perhaps the finest large aperture photographic lens ever produced, and yet the Speed Booster ULTRA m43 transforms it into a 39mm f/1.0 lens with even higher MTF. In fact, the resulting combination is likely the highest-performing f/1.0-class photographic lens available to the public."
https://www.dpreview.com/articles/5547568336/metabones-speed-booster-ultra-for-micro-four-thirds
Chris Young
"The MTF curve in Figure 3 indicates that the Speed Booster ULTRA m43 has truly phenomenal performance at f/1.0, which is the output aperture you will get when the master lens is set to f/1.4. Extremely low levels of aberration in the Speed Booster ULTRA m43 combined with the aberration-reducing tendency inherent in focal reducers means that even extremely high performing lenses such as the renowned Zeiss Otus series can actually be improved! This is illustrated in the pair of measured MTF graphs below in Figure 7."
"Measured MTF Using a 55mm Zeiss Otus as the Master Lens:
The 55mm f/1.4 Zeiss Otus is widely recognized as perhaps the finest large aperture photographic lens ever produced, and yet the Speed Booster ULTRA m43 transforms it into a 39mm f/1.0 lens with even higher MTF. In fact, the resulting combination is likely the highest-performing f/1.0-class photographic lens available to the public."
https://www.dpreview.com/articles/5547568336/metabones-speed-booster-ultra-for-micro-four-thirds
Chris Young
The Speed Booster XL (0.64x) was really designed for full frame lenses. For APS-C lenses the Speed Booster Ultra (0.71x) is the safer bet.
The Sigma 18-35mm has pretty good coverage for an APS-C lens, so the amount of vignetting with even the Speed Booster XL is often not very noticeable. Part of the reason for this is that the GH5 has a 4:3 aspect ratio sensor which fills the full Micro 4/3 image circle, so when you shoot in 16:9 aspect ratio in video mode, you are effectively cropping portions from the top and bottom and no longer getting as close to the edges of the image circle. When you would most notice the vignetting on the GH5 would be when shooting 4:3 aspect ratio stills, or in the 4:3 aspect ratio anamorphic or 6K photo modes.
On the Z Cam E2 and the GH5s (both share the same sensor), the sensor is a larger, multi-aspect ratio sensor, which means that it fills the full Micro 4/3 image circle even when shooting 16:9 aspect ratio video. So you will see some vignetting toward the wide end of the lens with the Speed Booster XL on these cameras, although it is not too extreme. Here are some examples with the GH5s:
https://davidmorganjones.net/blog/vignetting-panasonic-gh5s-sigma-18-35mm-f1-8-speedbooster-ultra
Of course this is just the performance with one lens, it's also worth considering that you might use other lenses in the future with the same Speed Booster that have different amounts of coverage.
It's true that the 0.64x XL gives about 1/3 stop more light and is slightly wider than the 0.71x Ultra. But the Ultra is more versatile as it can be used with both full frame and APS-C lenses with 100% coverage. Combine that with the better optics of the Ultra as Chris mentioned above, and it seems like the Ultra is the better all around option.
The Sigma 18-35mm has pretty good coverage for an APS-C lens, so the amount of vignetting with even the Speed Booster XL is often not very noticeable. Part of the reason for this is that the GH5 has a 4:3 aspect ratio sensor which fills the full Micro 4/3 image circle, so when you shoot in 16:9 aspect ratio in video mode, you are effectively cropping portions from the top and bottom and no longer getting as close to the edges of the image circle. When you would most notice the vignetting on the GH5 would be when shooting 4:3 aspect ratio stills, or in the 4:3 aspect ratio anamorphic or 6K photo modes.
On the Z Cam E2 and the GH5s (both share the same sensor), the sensor is a larger, multi-aspect ratio sensor, which means that it fills the full Micro 4/3 image circle even when shooting 16:9 aspect ratio video. So you will see some vignetting toward the wide end of the lens with the Speed Booster XL on these cameras, although it is not too extreme. Here are some examples with the GH5s:
https://davidmorganjones.net/blog/vignetting-panasonic-gh5s-sigma-18-35mm-f1-8-speedbooster-ultra
Of course this is just the performance with one lens, it's also worth considering that you might use other lenses in the future with the same Speed Booster that have different amounts of coverage.
It's true that the 0.64x XL gives about 1/3 stop more light and is slightly wider than the 0.71x Ultra. But the Ultra is more versatile as it can be used with both full frame and APS-C lenses with 100% coverage. Combine that with the better optics of the Ultra as Chris mentioned above, and it seems like the Ultra is the better all around option.
Thomas Smet
Veteran
The 0.64 XL was Really designed to combat the extra crop factor shooting video on the GH4. Its a special model really and while it works on the GH5 that extra boost was really designed to combat a specific sensor.
It is my understanding that little extra distortion was more difficult to do which is why most focal reducers stick to the 0.71 range and why we don't have something like a 0.50x adapter. It is just too hard to magnify past a certain point. I think that's partially why the 0.71x adapter can perform slightly better optically. The 0.71x is also clearly a bigger seller since it works with a lot more cameras and lenses and I doubt we will ever see a 0.64x adapter from them ever again.
As nice as it is to get an extra 1/3 stop its only 1/3 stop and not likely anything to make or break a project. If you don't have enough light to make 0.71x work it won't be enough for 0.64x either.
It is my understanding that little extra distortion was more difficult to do which is why most focal reducers stick to the 0.71 range and why we don't have something like a 0.50x adapter. It is just too hard to magnify past a certain point. I think that's partially why the 0.71x adapter can perform slightly better optically. The 0.71x is also clearly a bigger seller since it works with a lot more cameras and lenses and I doubt we will ever see a 0.64x adapter from them ever again.
As nice as it is to get an extra 1/3 stop its only 1/3 stop and not likely anything to make or break a project. If you don't have enough light to make 0.71x work it won't be enough for 0.64x either.
Thanks everyone, the condenses is The Metabones Ultra............but for the Sigma 18-35mm a little vignetting may be seen when the lens is wide open. Thats a bummer but if you want to use that lens it's something you'll need to deal with. They say at f2.8 you can't see it any more.
I'm tempted to go with this, The MFT DZOFILM 20-70mm T2.9 Parfocal Cine Zoom Lens @ $1499.00..............check out the review. https://youtu.be/4RPYe4ulQaA
I'm tempted to go with this, The MFT DZOFILM 20-70mm T2.9 Parfocal Cine Zoom Lens @ $1499.00..............check out the review. https://youtu.be/4RPYe4ulQaA