Hi Everyone
  After building few planes now i want to build a QuadCopter.
 
My main purpose is aerial photography so it should be easily able to lift a DSLR or a gimbals( w/ brushless motors)
I want a time of flight of 25 min

I am very confused about selecting the motor and battery.

Can anyone make suggestions.

Hobbyking links preffered

Thanking You in advance

For that you need a really big quad or maybe a hexacopter... Especially if you want 25 min flight time and not advisable if it is you're first...

I dont mind reducing the time of flight

I would suggest you to go for a 680mm hexacopter frame as minimum for lifting up a dslr with gimbal on a small frame flight time will be less

Ready made frame... Tarrot us the best, but they are pricy and so are their motors... But if you want good quality they can be almost as good as the dji s800...

In my opinion why not first build a normal quadcopter and then upgrade it for aerial photography/filming purpose.

True... Quadcopters and multirotors are very different from planes when it comes to flying... I am really good with quads and helis but have crashed my first plane twice already...

Well i do t want to advertise but i am selling frames same as tarot ones both 650mm quad and 680mm hex are available at very good prices (cheaper then tarot frames )
Quality and functioning is the same

Hi

First i am building a simple quad only

but while buying the parts i want to get the parts that would suit my next plan too instead to buying new parts

I did not mention that while using dslr i do not want to use an axis stabliizing gimbal only the cam

I thought of buy some gimbal for small camera like go pro

i want to make it interchangable to use both

680 mm hex will be good enough
320kv motors of sunnysky
40a opto esc
1550 props dji style
6s lipo
Will be good enough

From what I understand, this is your first multirotor and flying a quad is not same as flying a fixed wing, if you thought so.

Build a quadcopter, get it flying (without a camera and such fancy stuff) and practice until you learn to build and fly very well, without breaking a prop or two on every pack. You can put an expensive camera on it later and fly with confidence.

Btw, you'll burn, crack and break a few things the first time, so make sure you buy some cheap equipment. You don't want to break an APM, trust me, that's painful!

Well thats true never mount camera on your system until you have test flown it and are through with its handling and confidant enough about flying it
Only then put up a gimbal and camera on it
You can give me a call tmrw morning
7678013993
I will help you out for building it

Thank You so much everyone for your help 

Most welcome

Ok... I planned for that too... U would suggest the ntm propdrive 35-48 the 1100kv version... If you look at the data sheet it gives really high thrust at higer cell counts...

Contact Chintal he can help U out in a better way. n if u don ve any experience in flying Quads then probably U shd go with a simple model learn it then keep it as ur first quad so that u can fly it any other time. then go for a higher version so that u wld bear minimum losses.