Advice on photographing tigers can be split into two fields. From Elephant or Jeep.

Elephant

Carrying long lenses on top of elephants is out of the question. There is nowhere to support the lens and it has to be hand-held. An ideal lens is a 300mmf4 IS lens. This is very small, light and compact and has the added bonus of an Image Stabiliser which will correct camera shake up to two stops. I always wait until the elephant is completely still before shooting, any movement at all will blur pictures.

One other thing to consider with elephants is camera angle. If the tiger is at the same level as the elephant you will usually be looking down on top of its head. If possible get your mahout to move the elephant into a depression so as to obtain a more pleasing eye level angle.

Film depends obviously on the conditions but Fuji Provia 100f F is a good all round bet as it can be operated quite easily to 200 or 400 ASA if necessary.

Jeep

The most important piece of equipment for photography from a jeep is a beanbag! Tripods etc are out of the question in my opinion as they restrict movement and freedom. Before you have set your shot up you will have invariably missed it.

300,400,500 mm lens will all sit nicely on a beanbag and offer excellent support with restricting movement. Beanbags can be placed on any part of the jeep and your lens will mold into the bag.

Film should be slow for the finest quality. Fuji Velvia or Provia 100f are perfect and can be blown up to huge sizes without losing quality.