----The position of the angry one is dominating in the picture, which justifies his placement....he is at rule of thirds shot by 300mm telephoto lens. it is not tight in frame so both look comfortable ....left one is also looking into the frame .
----Next to match the perch of the left on on stone, which is generally heavy in weight, so this well contradicts the higher pipe supporting the aggressive bird........see into his eyes-the expressions---they r also contradicting with the left who is rather silent.....(nay be giving reply by her/his gestures or slow voice.......the postprocessing done is slightly reducing the noise, as the image is cropped 3/4th and shot at ISO400....aperture f5.6.
-----Light - no flash but depending on natural light, which well suits the picture. ....Framing is natural and done in the viewfinder.......There is hardly any question of depth of field, which is short covering well the birds......the picture suits in rectangle frame and easily viewed from left to right as we are habitual in writing from left to right.
----The is slight tilt of the pipe, which being slightly diagonal adds strength in the picture......(imagine it in upright position).
----In cloudy sky, filter are unnecessary to be used except the UV filter, which cuts ultra-violet rays in the atmosphere and also work as lens protection.
----The aggressive bird by shaking badly its wings breakes the monotony in the picture, in comparision if both were silently sitting on their respective perch then u had less interest to view it as a creative picture.
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