ALEXA on the biggest ever Indian movie

"Baahubali" is a sweeping action-adventure drama set in medieval India, chronicling a struggle for power in the fictional kingdom of Mahishmathi. Written and directed by S.S. Rajamouli, it will be released in two parts, with a host of different language versions aiming for success across a range of international markets. Cinematographer K.K. Senthil Kumar worked with ALEXA XT cameras and Master Prime lenses, utilizing the ARRIRAW Open Gate format for maximum image quality in VFX-heavy scenes. Kumar spoke with ARRI about his equipment choices and his experiences working on the most expensive, ambitious film in the history of Indian cinema.

This was the director's first digital movie, but you have collaborated with him several times before; how would you describe the working relationship?

"Baahubali" is my sixth collaboration S.S. Rajamouli. In 2003, I shot my first movie SYE with him and since then, I feel we've been on an exciting and diverse journey through all our films together. "Baahubali" is yet another step in an entirely new direction regarding story, style, vision and scale, with a lot of new challenges and opportunities. One of the things that I love about working with Rajamouli is that he is very particular about getting the visuals right and to this end, has always given me the freedom to choose the camera and associated equipment.

What made you decide to shoot with ALEXA XT cameras?

This is India's most expensive movie to date and we needed a very reliable camera; I knew I could count on the ALEXA XT to faithfully convey to the viewer what I was seeing. I love the flexibility that the ALEXA has and I'm very impressed with how skin tones are rendered -- our cast is diverse and the ALEXA handled all our skin colors beautifully. To my eyes, there is no other camera that can handle this as well; there's a certain softness to it, almost an organic grain structure. I feel it's the closest I can get to a film look or even better, with a soft patina that isn't as harsh-looking as some other digital cameras. In the DI suite, I didn't need to do as much defocusing, softening, and contrast reduction as I might have had to with another camera. The ALEXA's low-light sensitivity was also a huge bonus; I definitely think we were able to use smaller lighting instruments in general than we would have in the past.

Why did you record in the ARRIRAW format, and how did you use the Open Gate mode? 

We had to shoot in different locations with varying weather conditions, from continuous rain in Mahabaleshwar to scorching summer heat in Hyderabad and then freezing cold in Bulgaria. Attempting to battle the weather gods is fruitless, so latitude was the only option. Gathering as much information as possible meant I could decide on the aesthetic look I wanted -- ARRIRAW was the obvious choice. The extensive visual effects in the film were another reason why I chose to record ARRIRAW, the highest quality possible with ALEXA.

I like the Open Gate format, as it records the full 3.4K sensor area for an optimal up-sample in post to a 4K DCP, which we did with spectacular results for some cinemas that have 4K projection. For the majority of the film I shot ARRIRAW 4:3, going to ARRIRAW 16:9 for 120 fps shots and using Open Gate for VFX shots. The film integrates approximately 2,500 VFX shots; we shot greenscreen as extensions of existing sets, and the ALEXA is quite beautiful for greenscreen work.

Were there any other features of the ALEXA XT that proved helpful on this production?

One thing I really liked was the frame-accurate lens data information about the focus, iris and zoom settings of a lens, as well as the depth-of-field range. It reduced a lot of our time and effort on the set, but also in postproduction. All the plates and VFX elements were done with the camera and it all looks great. The time it takes to switch from regular to high speed mode (60 - 120 fps) has been reduced to about 20 seconds, which also saves a lot of time.

Why did you choose to work with Master Prime lenses? 

The Master Primes are very precise and deliver really sharp images without sacrificing texture. There's something beautiful about the output, a softness that doesn't feel out of focus. The Master Primes also give images a more voluptuous feel -- other lenses are more rigid in terms of the way the light rounds objects. Also, I felt that the Master Primes seemed to be the most flexible with different faces and they help a lot with getting a very nice skin texture and color; in fact these were the nicest skin tones I've ever seen on digital.

How much of your look creation was done in the grade, and did you find the ALEXA images easy to work with?

Very little was done to the image settings on set. We had our DIT who downloaded and checked the clips, and made the proxies. The first approach to making color adjustments was in the grading at Annapurna DI Studios. Once you put a shot on the Baselight and start working with the footage, you can really see the power of ARRIRAW; the uncompressed image lets you push shots in ways that you would never be able to do normally. 

One of the great things about the ALEXA is that, because it creates such a beautiful raw image, you have a lot of room for moving the image in one direction or another in post. The ALEXA has such nice highlights and a beautiful color range, so you can make those subtle manipulations and it looks very organic, rather than electronic. 

Would you say that this is an important film for the Indian film industry?

This film will give international audiences a taste of Indian folkloric culture in the same way that "Crouching Tiger, Hidden Dragon" exported China's mythology. I haven't seen a film of this scale that is so true to Indian culture, but at the same time the emotions portrayed are universal. We hope that not only does this movie portray India's rich culture and traditions, it also conveys to the world the sophisticated film industry India has developed and the kind of technicians we have -- I won't hesitate to say that they can compete with the best in the world.