P+S Technik T-Rex Question

[Reg Voges]

I am the DIT on an Alexa job where they will be using the P+S Technik T-Rex Borescope to shoot fish in a tank of water. The effect would be to have very imposing, macro shots of the fish. I would like to know how much light will be lost in the T-Rex and if it is the best lens relay system to use with the Alexa. The alternative would be an Excellence Optex system.

[Dom Jaeger]

The widest aperture on the T-Rex is T7.1 compared to T5.6 on the Optex, however with just the borescope head on the T-Rex the maximum aperture opens to T5.6 as well.

 

While the Optex is basically a borescope with a periscope module the T-Rex has many more features - 360 degree image rotation, a lens head that can pan 360 degrees around a horizon that can be tilted by up to 18 degrees, and a 2:1 zoom barrel.

 

The Optex is probably a bit sharper, with less fall off at the edges, though they're pretty similar if the T-Rex is simplified to just a borescope, and there are more lens options with the T-Rex.

 

For straight macro work like shooting a fish tank the Optex is probably a better (and simpler) option, and most likely cheaper to rent.

 

We've never had any issues with either system used on Alexa.

[Reg Voges]

Thanks Dom,

 

We ended up using the Optex as it had a slightly sharper image and a better light flaring quality - which is exactly what the DOP wanted. There was no need for the T-Rex's image rotation or other functions - although it was a marvelous lens system and tested really well on the Alexa. The Optex borescope was very simple to use and initially the DOP hoped that it would have a PL mount adapter for Master Primes, but the one we got could only use the Optex Field-of-view lenses. Apparently there is a PL mount available for the Optex.

 

The result was very impressive and I can recommend either lens systems to be used with the Alexa, depending on your need.

 

Reg Voges

Digital Imaging Technician

Cape Town

South Africa