そろそろ ('soon, any time now') is a common discourse marker for gently prompting someone to start an action. 人物写真 ('portrait photography,' literally 'person photograph') contrasts with 風景写真 ('landscape photography'). でも softens the suggestion to 'something like that.' ~たらどうだ is the standard casual suggestion form: 'why don't you?' The reply shows characteristic hesitation — half-confirming, half-demurring with trailing ellipses. スナップ ('snap') is the loan for 'snapshot.'