Chennai to Pune - bus or train?

Summary:

I'm looking for the best photo-taking reasonably priced journey experience when travelling by land from Chennai to Pune in India.

This seems to leave a bus vs train choice.
Car travel options that I have seen seem to be very substantially more costly.
[Train 'sleeper' about $10!. AC sleeper compartment about $25 - $50. Buses sleeper or semi-sleeper around $40. Car - $hundreds ]

Detail:

I'm intending to fly to Chennai in India and then travel 'by land' to Pune - about 1100 km away. This is my first visit to India. My intention in travelling by land rather than flying to Pune is to get a first feel for the countryside. When travelling by bus or train I take many photos and I value being able to do so - dirty windows are a usually unavoidable hazard which I accept (although I have been known to clean the outside of a window by my seat :-) ).

I have been told that travelling by bus is liable to be far more arduous than by train. I have been told that the photo opportunities 'by train' will be about as good as 'by bus'. In other countries this is not always true. (eg in Malaysia the train runs for large distances through palm oil plantations with very few extended views - and these are mainly at road crossings where there is also a settlement.)

Indian travel sites indicate that the fastest land journey from Chennai to Pune is by express bus (about 20 hours) with the fastest trains taking slightly longer - which contradicts the "buses are a hassle" suggestions.

Web suggestions are that train windows may offer limited views in "AC" compartments. Buses may offer a photo advantage if a window seat can be obtained. However, if the buses run in low visibility highways a train may be better.

Does anyone have personal experiences to offer?

Resources:

" Make my trip" Chennai to Pune trains

90 degrees Chennai to Pune trains

India: classes of train travel

Photos of train interiors

5 cheapest buses Chennai to Pune 20 to 23 hours

5 fastest buses looks much the same

Route directions {by car}

________________________________________

Travel report :-)

In mid 2014 I took a train Chennai - Pune.
"Hard sleeper" non AC, 2nd class (or 3rd or none? ) :-)
About $US4.50 for a 20 hour 1000 km trip. (No bedding - take your own).
It was utterly marvellous.
I was adopted by the cleaning crew and allowed to use their sole inter-carriage window seat whenever I wished. Big wide spaced bars curving outwards gave excellent camera location with (some) protection against "stuff".
2000 photos :-).
Countryside towns people water temples crops, ....... .
Marvellous.