Is it true that the kowa cine prominar spherical lenses are based on speed panchro and super baltar optical designs?

[Edith blazek]

I ask as I've seen some say this but I've also heard that it's not true given the character of the prominars versus those other lenses so if anyone with more knowledge than me could confirm or deny that would be great.

[Simon Wyss]

They are according to this site. https://industrycamera.net/equipment/35-mm-vintage-lenses/kowa-cine-prominar-lenses/

[Edith blazek]

5 minutes ago, Simon Wyss said:

They are according to this site. https://industrycamera.net/equipment/35-mm-vintage-lenses/kowa-cine-prominar-lenses/

And lensworks also says that but the reason I'm asking here is that I don't know if that bit is just rental house conjecture where they're just saying that to boost rentals as again, some say they're not so i wanted to know if anyone definitively knew.

[Edith blazek]

Bump, can anyone affirm or deny whether the rental houses are correct in saying the kowa cine prominar sphericals are based on cooke speed panchros and Bausch and lomb super baltars?

[Dom Jaeger]

Like many, many fast lenses, they are all variants of the unsymmetrical double-Gauss design that originates with the Cooke Opic or the even earlier Zeiss Planar. 
 

 

Usually copying a lens exactly infringes patents, so lots of lens designs are small variations on the same idea. Sometimes a company like Zeiss would licence another manufacturer to make exact copies of their lenses, so you might have Tessars made by the French firm Krauss, but I don’t think Kowa were licensed to copy either of the lenses mentioned.

Cooke Speed Panchros and Bausch and Lomb Super Baltars are also quite clearly not the same lenses, and even within a set of each of these there are different designs for different focal lengths. So saying a lens set is “based on” both of these lens sets is an utterly vague statement that could literally mean anything. On top of that, you have design variations within different iterations, so for instance the MkII 25mm Speed Panchro is a different design to the MkIII 25mm Speed Panchro. Which one do you want to pick? 

So sure, Kowa Prominars were based on Speed Panchros and Super Baltars, the same way Star Wars was based on Buck Rogers and Kurasowa movies.