It must fit within the BA carry-on limits (56 x 45 x 25cm / 22 x 18 x 10in) and it needs to carry 2 x M1ii bodies, 300 Pro, 40-150 Pro, 12-100 Pro, a wide and standard prime or two, assorted converters/filters/tubes/batteries/chargers, plus a mini laptop or iPad Pro, medication & valuables, a few spare clothes and other bits and pieces.
It must have a top opening to a compartment deep enough to hold a Mii/300/EC-14 pushed in vertically (this is for use on safari game drive vehicles). It needs to be strong enough to stand days of kicking around in dusty, crowded vehicles and buses.
It needs to be a comfortable carry on short hikes when loaded, and I have a reasonably long back.
I reckon I'll need something between 30 - 40 litres, and weight of the pack itself is not of great importance because BA has no hand baggage weight limit (although lighter is obviously better).
Having looked up the specs of the current ranges of bags from F-stop, Peak Design, Clik Elite, Manfrotto, Mindshift and Mountainsmith, I reckon the Lowepro ProTactic 350 or 450 AW II have the best balance of cost and boxes ticked for me.
I do have a range of photo inserts that I could use in a general rucksack, but I don't find the smaller general rucksacks I have at the moment very practically usable like this.
So, before I go off loaded with gear to a shop to try these out to see if I can get everything in the 350, does anyone please have any personal experience or other suggestions they could share?
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