I have been looking for a replacement backpack since I threw out my old Lowepro CompuTrekker AW which I'd purchased in 2008 because Sam (my late cat; rest his soul) decided of all things to use the bag for a kitty litter box. Frankly the damned thing stunk after that. And there was no way to deal with the smell that permeated into it. So out into the trash it went.
I wanted to make sure that I found a bag that fit my needs. In fact, I need the equivalent of two bags: the first being a sling day-pack which I will be able to carry both my Nikon D300s, my 70-200mm f/2.8 VRII with TC-20EIII extender attached and my 18-70mm f/2.8 along with my filters, in a comfortable position. The second being a day-hiking backpack with room enough for all my lenses (including my 70-200mm f/2.8 VRII; TC-20EIII extender, my 18-70mm f/2.8 and my 50 f/1.8D. I know that I'm going to have to spend at least $800.00 minimum on both bags and that's going to take a large financial chunk out of my pocketbook. Invariably I'm looking for something that works.
Not to go into a big history on why backpacks/slings have to work for me; it's in regards to a nagging back injury suffered in 2006 when I fell down a set of stairs impacting my back in three places resulting in nerve damage to the back causing pain and fatigue if any load to my back isn't properly supported. Hence the reason why my search for a proper back-pack or sling has been fraught with missteps and unfortunately, I haven't found the right backpack or sling yet.
The purchase of a slingbag needs to have the weight properly aligned across the back or it will cause strain to your shoulder muscles. Invariably, you are carrying at least 10 lbs of camera gear. A camera body will weigh around 1.5 lbs with camera battery, memory card, body cap, and monitor cover. The Nikon AF-S VRII 70-200mm f/2.8 G ED weighs around 3.5 pounds; the Nikon 18-70mm f/3.5-4.5 DX G ED lens weighs around .85 pounds and the 50mm f/1.8D weighs .35 lbs. Now this is not including all manner of other gear such as .5 lbs worth of binoculars which can easily add about 2-3 lbs to what you're hauling around. And even 10 lbs if not supported correctly can do a number on your back.
The temptation to go economical in terms of camera bag is great as most casual camera bags from Lowepro or Tamrac will cost you between $200-300 depending on the amount of camera gear that you carry. There are other well-known camera bags out there but I'm not about to go into the vast array of well-known options there are out there which eventually I will get into depending on what I need to purchase in terms of gear. I'm going to be concentrating on the casual camera setup usually consisting of a telephoto lens (70-300 f/4.5-6.3)/70-200 f/2.8), a wide-angle and either a macro or a superwide and the bags that can fit that.
I purchased an Impecca DCS205K large camera sling-bag several years ago to try to figure out an easier way of carrying the camera equipment that I carry on a regular basis to shoot with. That was a big mistake to not go Lowepro. First the camera strap connection went requiring a ad-hoc repair job which threw the camera-sling bag balance out of whack, putting more stress onto my shoulders. But I persevered thinking that I spent a lot of money even though the cost was cheaper than the Lowepro; in the end though, the wear and tear on my body from the unbalanced bag wasn't.
Impecca is not known for its expertise in camera bags and I highly recommend rethinking a purchase. From now on, it is Lowepro, Tamrac or a recommended bag from a camera bag manufacturer that has been rated as experienced in producing bags for the professional photographer. You can't just put a bunch of padding into any old bag and call it a camera bag.
I have been currently looking at a hiking daypack from Lowepro with enough room to store my camera gear...and survival gear. Eventually I will upgrade from there to a Alpine type camera backpack with room enough for a camera pack insert and survival gear as well as hardy enough to pack a tent-roll over the top of it. It'll be necessary if I intend to do a Great Bear Rainforest trip at one point in my life, but at 46 years of age...that time is rapidly receding.
This bag, a LowePro is a bag that I've been looking at acquiring. It appears to have enough space for extra clothing (just in case I need it during the course of a day-hike) and a survival kit. It also has straps to attach my Manfrotto 190XB tripod which makes it even more useful. The straps are padded enough to spread out the weight and the camera bag insert contains enough room to secure my Nikon D300s with 70-200mm f/2.8 attached and my 18-70mm f/3.5-4.5 lens. Perhaps I can make enough room to put my TC-20EIII extender there too.
Note that camera bags will not invariably contain enough room to take everything that you own in terms of camera gear so you will have to pick and choose which lenses and shots are important to you for that particular trip. If I'm going landscape shooting, I leave the 70-200mm f/2.8 VRII at home and take my filters, because I need the filters more than I need to carry a telephoto lens for a quick wildlife shot. If I'm going to go and shoot wildlife, I'll leave the wide-angle lens at home. It's a matter of priorities now and focus on the shot. You don't want to wander around the park or where-ever stiff and sore because you over-stressed your back carrying all your gear with you in a backpack that is improperly balanced. You want to have the right gear with you for your trip focus (whether it be wildlife for that particular trip or landscapes for that particular trip or the right gear for whatever your genre). You don't want to overload yourself with gear you may not need for that trip and you don't want to have an improperly balanced bag which will ultimately cause you physical problems. This is where the right camera bag will make all the difference in your shots.