Difference between original Speed booster and the Ultra 0.71x

[amsh89es335]

Hi what is the difference between the original Metabones Nikon G to Micro Four Thirds Speed Booster and the newer Metabones Speed Booster Ultra 0.71x Adapter for Nikon F-Mount Lens to Micro Four Thirds-Mount Camera?

Was there any improvement added to the class or mounts with the newer one? 

Looking to buy one used. 

[webrunner5]

Looks like it went from 1.5 to 1.7 and has more exotic glass in it, etc..

https://www.wexphotovideo.com/metabones-speed-booster-ultra-nikon-g-to-micro-four-thirds-1591252/

[aldolega]

The optical design was updated for the Ultra, and I believe it uses a better quality of glass as well. The designer is actually on this board, Brian Caldwell. Maybe search for his username and you can find his older posts where he explains the exact differences.

[Spgreen65]

Think of the ultra for Apsc lenses and the xl for full frame.  The 18-35 sigma won’t vignette on the Ultra and the GH5. If you don’t use apsc lenses with a gh5.  You probably won’t need the ultra. It really depends on the crop factor of you camera. 

[Cinegain]

The XL never got mentioned.

• http://www.metabones.com/products/details/MB_SPNFG-m43-BM1 VS
• http://metabones.com/products/details/MB_SPNFG-M43-BM3

[Brian Caldwell]

On 6/18/2018 at 8:38 AM, amsh89es335 said:

Hi what is the difference between the original Metabones Nikon G to Micro Four Thirds Speed Booster and the newer Metabones Speed Booster Ultra 0.71x Adapter for Nikon F-Mount Lens to Micro Four Thirds-Mount Camera?

Was there any improvement added to the class or mounts with the newer one? 

Looking to buy one used. 

The Ultra uses a significantly better optical design, with very high MTF and insignificant corner falloff.  As a result, the Ultra will sharpen up any lens that is attached to it, including the Zeiss Otus series.  Below is a very detailed MTF comparison of the original M43 Speed Booster, the Ultra, and the XL.  The XL is also very sharp, but is a little more specialized than the Ultra.

 

[webrunner5]

Wow the Ultra is just crazy good on the MTF chart. Impressive would be a understatement!