There is no end of acquiring them, the search for the perfect camera bag seems endless. Here are some of mine, and some thoughts on them.
The now discontinued (looks like Ortlieb stopped making camera bags altogether), but still available, Protect is a compact, waterproof bag in the tradition of Ortlieb robustness, with a slider closure which is easy to operate in big gloves. The inside of the bag is made of a thick closed-cell foam that gives it rigidity, but, unusually for a camera bag, is not lined with fabric. It is officially IP54 rated (though I am fairly certain that when I first got mine it was sold as IP67; I believe there were issues with the slider seal in cold temperatures). Size wise it is just big enough for my old Lumix GF-2 with a 14-70mm kit lens.
The great thing about this bag is that it can be comfortably hung with a couple of carabiners on backpack shoulder straps, providing fast and easy on-the-go access. This makes it an excellent mountain biking and skiing solution for smaller cameras.
I got the Protect on a recommendation of a friend about a decade ago, and it has served me faithfully ever since. I love its simplicity and wish it was just a little bit bigger to accommodate my Lumix GX-8 camera, which brings me to the next bag ...
The Compact-Shot is yet another great, but discontinued, bag from Ortlieb. It is slightly bigger than the Protect, just enough for my Lumix GX-8 with a 12-40mm zoom, but unlike the Protect, the internal padding is lined with a soft cloth, as is normal for camera bags, and there is a small internal pocket. The zip closure is not as easy / fast to open as the Protect slider, and is quite awkward to close fully, but when closed the bag is IP67 rated.
The Compact-Shot has become my default bag of choice when I don't need to carry any extra lenses, and, chest mounted with a couple of carabiners, the bag I use for ski touring.
Thule Perspektive Compact Sling
The Perspektive CS is a roomy bum-bag. It is made from a water-repellent fabric, uses water-resistant zippers, and comes with a detachable stowaway rain cover. It is big enough to take my Lumix GX-8 together with 12-40mm and 40-150mm lenses (with either lens fitted), has a padded iPad Mini-sized pocket inside, as well as a phone pocket on the outside of the lid, and comes with a plenty of adjustable dividers for the inner space.
The waist strap with side stabilisers makes the bag very stable, enough to jog with. The bag is compact enough to combine with a small, high sitting, backpack, up to something like the OMM Adventure Light 20, which makes a good combination for fastpacking trips. The only thing I'd change on the belt is to extend the padding fully under the D-rings, as this would make it more comfortable (I have done a couple of very long fastpacking days with this bag, and was beginning to curse the D-rings near the end).
The one issue I have run into with this bag is that the rain cover is to easy to detach, and the connecting strap will often self-detach when the cover is on -- this makes it easy to loose when taking it off in windy conditions. But overall, this is a well thought out and made bag.
LowePro Flipside Trek BP 350 AW
The Flipside is my 'pottering in the woods' backpack, but also the camera bag I am most ambivalent about. On the upside, it is very comfortable to carry, the camera compartment is spacious enough when I want to bring the big lens and more, and the through-the-back access is handy.
But there are some, to me at least, fairly significant design flaws. The non-gear storage space is very limited, enough for a sandwich, a small water bottle, a light-weight jacket and perhaps an extra thin layer. The lack of internal space is aggravated by the mesh side pockets being both small (i.e., too small for the like of a litre Nalgene bottle) and rather shallow (the bottom half of the pockets is made from a non-stretchy material to make it more durable, but there is not enough of it, so, e.g., normal 0.5l drinks bottle cannot be inserted all the way to the bottom). It is possible to strap things, such as a tripod, on the outside of the bag, but then you have to forego of the built-in rain cover, which is rather snug fitting.
Had there been another 3+ or so litres of non-gear space in this bag, this would have been my ideal camera day-bag. As is, I have strapped an external 5 litre pouch on the back of it, but like I said, that makes the rain cover useless, which is sub-optimal in the normal Scottish weather.
Tenga BYOB 9
Tenga get around the basic problem with camera backpacks (they never really work well enough; see above) by providing a range of minimal padded camera inserts that you put into a bag of your choice. The model number is the depth of the bag in centimetres, and the BYOB 9 is just big enough for my Lumix GX-8 with 12-40mm lens + another lens of a similar size, and either another pancake prime, or a few extra bits and bobs, such as a remote control and a blower.
The great thing about the BYOB is how the sizes of the bags in the range were chosen -- for a given camera size you get optimally low profile bag easy to place at the top of a normal sized backpack. The main downside is that the padding is inexplicably thin (about half of that on my other camera bags); I'd prefer more protection for my kit. Also, although the fabric is water-repellent, the zip is not, so I always feel it necessary to put this inside a dry bag.
Crumpler Light Delight 200
My default running camera is Lumix GM-5 with a 14mm pancake prime lens, and it's proven rather difficult to find a good pouch for it that could be shoulder mounted. The closest I have come to is the Light Delight 200. It's slightly wider than ideal for the GM-5, so I padded it with a strip of an old sleeping map to stop it from moving about when I run. On the upside, the depth is just enough for a 20mm pancake fitted.
Overall this pouch is well made and well padded. The back has a Velcro strap for attaching it to Crumpler backpacks, but it can be attached quite well to OMM packs with a bit of a string, and some creative knotting.
The main downside is that the bag is not even remotely rain proof. Also, the top zip has two sliders which annoyingly rattle when running, so I promptly removed one of them. With that modification, I have happily run hundreds of miles with it.