ARRI Ultra Prime vs Zeiss Standard Speed

[Uli Meyer]

Apart from the obvious difference in size, built and mechanics, is there a big difference in character between a Zeiss Standard Speed and an Ultra Prime. I’ve recently shot footage with both and couldn’t really spot any. What do you think? 

[Robin Phillips]

its always been my impression that theres a little more blue rendition in the standard speeds, but the main thing you get with the ultra primes is the sharpness, even when at T2. granted I havent tested them against each other with charts, but thats always been my impression. the ultras are definitely shaper than the old super speeds wide open

[Uli Meyer]

14 hours ago, Robin Phillips said:

its always been my impression that theres a little more blue rendition in the standard speeds, but the main thing you get with the ultra primes is the sharpness, even when at T2. granted I havent tested them against each other with charts, but thats always been my impression. the ultras are definitely shaper than the old super speeds wide open

Thanks Robin! You may be right in regards to the blue rendition. I'm planning a short film and would have a complete set of the focal lengths I need if I mix my UPs with my Standard Speeds. Just wondering if that would be noticeable.

[Dom Jaeger]

Stopped down, not so much difference, but wide open UPs are cleaner with better contrast and even illumination.

There’s about 30 years of optical advancement between them, so definitely an improvement in aberration correction, field flatness etc. But Zeiss glass and coatings tend to match well even over decades. 

UPs have more adjustments, so if someone untrained has fiddled with one they can easily introduce issues like decentration that will degrade the image, whereas Standards tend to remain optically ok. They develop things like image shift from worn helicoids or loss of contrast due to coating scratches instead. 

[Robin Phillips]

8 hours ago, Uli Meyer said:

Thanks Robin! You may be right in regards to the blue rendition. I'm planning a short film and would have a complete set of the focal lengths I need if I mix my UPs with my Standard Speeds. Just wondering if that would be noticeable.

of all things, to my eye the Supreme primes actually seem closer to the standard speeds in color rendition than the Ultras. I assumed that was part of the design with the supremes, to basically provide a modern alternative to using the older glass. so that might be an alternative if you're super worried about color matching. But I think that generally most people wont notice either way since you can push things around in resolve a little if needed

[Uli Meyer]

Thank you @Dom Jaegerand @Robin Phillips! Your insights are very much appreciated!