Originally posted by Lowell Goudge What you need to decide is whether this is to be used to go from point A to B and pack everything you are going to possibly need (I.e. Everything you own) or something to carry a subset for actually working.
I find big bags are good for the former, but questionable about the latter.. . .
If you are truly going to get a bag that can be loaded to capacity, with 2 bodies, 3-4 fast lenses, flash, batteries etc, you are discussing in the range of 10-15 kilos (20-30 pounds roughly) If you intend to carry this for an entire day, forget being compact, forget being cheap, get a bag with proper straps, . . .
I agree 100 %
am I traveling by plane or car - the bag I take depends on that
if by car, am I going to leave equipment hidden in car, temperature permitting, and only take some on short walks or do I carry all
what do I expect to use on my " photography excursion " ?
what is permitted if I enter any facility/building ?
if so, where would I keep any prohibited items safely outside the facility/building
I once tried to enter a museum in Washington DC through metal detectors and realized that my expensive brand new multitool was prohibited because it has a small knife blade. I hid it in a planter outside and it was still there when I exited.
I got lucky
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admittedly I am no expert but when ever I buy a back pack I first look for features that makes the pack useful for carrying any type of load such as
(1) waist straps: I was taught that the majority of a backpack's weight, 80 percent or more, should be supported by your hips.;
(2) Load Lifter Straps: These are stitched into the top of the shoulder straps, and they connect to the top of the pack frame. Ideally, they will form a 45° angle between your shoulder straps and the pack. Kept snug (but not too tight), they prevent the upper portion of a pack from pulling away from your body, which would cause the pack to sag on your lumbar region and
(3) Sternum Strap: This mid-chest strap allows you to connect your shoulder straps, which can boost your stability. It can be useful to do so when traveling on uneven cross-country terrain where an awkward move could cause your pack to shift abruptly and throw you off-balance.
(4) good buckles and zippers
then I look for special features for the expected use of the back pack:
does the interior has the loop and hook dividers so you can personalize the interior as you choose,
multiple external attachment points and pockets,
a " rain " cover,
a separate padded section for a lap top and
how you can access the interior of the back pack
then I decide whether any or all of those are required by my needs.
I currently have 3 back packs and a " messenger " bag that I will use depending on my needs