This backpack is a beast. If you just have one camera and a couple of prime lenses, this is going to be overkill for you. Look for something smaller.
It is a very large, spacious pack with thick sidewall foam lining and heavy duty durable zippers. The back has air channels to keep things cool on long hikes, and the detachable waist strap helps with stability for long days of work. The backpack opens mainly from the back, which is a nice security feature. The main cavity has a ton of different dividers of differing thicknesses and lengths so that you can customize your load out. Each side has an opening for quick retrieval of a camera. The back also has a very well padded laptop sleeve that can easily store a 15" laptop. The pack also comes with a set of accessories to further customization. This includes two adjustable straps, a water bottle pouch, a zippered pouch, and a sleeve for the base of a tripod to tuck into. I am currently using that and one of the adjustable straps to secure my tripod to the outside of my pack.
I love this backpack and all of its features so far. It is so convenient for my profession, where everything is quick and spur of the moment so I need to have my equipment easily accessible at a moment's notice. It is a bit hefty, but incredibly comfortable. I don't even notice the weight anymore because of the comfort.
There are a couple things I think it is worthy to mention for potential buyers: I wish it had a little more padding in the bottom. I took the extra dividers I didn't need and layered them on the bottom because I felt like that's the one wall that didn't have quite the protection I hoped it would. Also, this pack is super padded other than what I just mentioned, so it does have a bit of weight to it. I'm guessing it's around 3-4 lbs., so it may not be the best for really long treks. Finally, I'll reiterate that it's a huge bag. I have one walk around lens, two primes, one body and a telephoto, plus video accessories like mics and handles and a monitor, and I STILL have a bunch of space left over. It is almost too big for me. I'm okay with this because I plan on using the top half as another suitcase for my upcoming vacation, but if not it would beg the question if I needed something smaller. Just keep that in mind.
For professionals, especially photographers working with multiple lenses and more than one body, this would be perfect for you. For others, as long as you have plans for the extra real estate left over, you will find this backpack equally as enjoyable.

So I am pleased with this bag. Quality appears to be awesome and I was able to get all my gear into it. My bag with great weights about 45 pounds and I walked 6-miles every other day to tweak it in and to prepare for a trip to Switzerland. Took me a few tries to get the straps set correctly but the bag odds comfortable. My back does sweat while hiking but I guess that can be expected.

I am a bag junkie. I have bags upon bags for work, personal use, old bags, new bags, etc. I work and travel in a lot of different environments desert, mountains, heat, snow, foreign locations, etc. I searched for awhile for a bag that could hold my DSLR, lenses, drone, laptop and iPad. I came across this one and watched the videos, read the reviews like everyone else. My only concern was I don't like tactical looking bags when traveling. I also don't like branding that draws attention to a bag that may have thousands of dollars of equipment in it. I took a sharpie and filled in the logo, the tactical look is getting pretty common so I don't worry as much and added some D-rigs for bottles and backpacking straps.

I pulled the trigger on this bag and I was not disappointed. Starting with protection, the bag is like a hard shell all around. That's great for the gear in it and takes the worry away from bumps and knocks. The hook and loop system on this is pretty nice. The included bags don't fit all the loops, the side loops on the bag are a little more narrow and won't take the water bottle, etc. Not a huge deal unless you load a lot on the back which could be a problem when you lay it down to open it up. The material is stellar, very durable and not concerned about dragging it wherever I go. Good zippers, good handles and all in the right spots for loading, carrying, etc. The exterior pockets are a bit small but will hold keys, passport and other small items. The overall size is good, it's not to big to take on airlines and doesn't feel awkward walking around town. The shoulder straps are a little narrow, with a full load and long haul may get a bit sore. Access from three points gives lots of options for staging gear.

Ok for the interior, wow. I still don't know how I am fitting as much as I am in this thing. The entire interior is customizable so take some time to figure out the layout and what you want quick access to. Here is what I have in my bag:

- Canon 5D
- Canon 70-200 2.8
- Canon 24-105
- Canon 17-40
- Canon 100mm macro
- Lens shades for all lenses
- Two lens filters
- Mavic Air 2 drone (in hard case)
- Mavic Controller
- ND Filters for drone
- 1 full set of extra blades for drone
- Three drone batteries
- Three camera batteries
- Mount for iPad on drone controller
- Landing pad for drone
- iPad
- Dell XPS 15
- SD and CF cards
- Cables for chargers
- Misc lens cleaning material

Ok so the cons. When travelling I like to carry lots of snacks, ibuprofen or whatever the trip calls for. This doesn't have a great miscellaneous compartment. I laid out the interior so the top access allows for miscellaneous items. It's not perfect but it works. No bag will be perfect but this is about as close a they get for equipment bags. When you consider all the options for the exterior there isn't much it can't do. I have all the gear I would need travelling or around town. If I could change one thing I would say slightly wider shoulder straps to distribute the weight of all that gear. If your on the fence pull the trigger it's worth every penny.

OVERVIEW

I do a lot of traveling for photo and video shoots and wanted a backpack for my photography gear. Additionally, when I travel overseas I wanted something that could fit my full frame 5D4 and my Mavic Pro. On top of all of that it needed to be durable, comfortable, and weather resistant. The Lowepro ProTactic delivered all of this and more.

WHATS IN THE BAG

In this single bag I am able to pack all of the following equipment. Even for it's size it is a little hard to zip close with the equipment, but if everything is perfectly arranged, the zippers do manage to close.

Camera - 5D Mark 4 with battery grip and tripod plate
Camera Strap - Fastfire strap fits next to camera
Camera Batteries - 4 extra camera batteries
Memory Cards - Extra CF & SD (Canon 5D4), and MicroSD cards (Mavic Pro)
Laptop - Small dell 13" laptop so that I can backup the footage in the field
Tablet - iPad Mini tablet that I use to control the Mavic Pro
Lenses - Canon 70-200 2.8 L (portraits, zoom, wildlife), Canon 24-70mm 2.8 L (events, portraits, landscape, low light venues, group portraits, weddings, video), Canon 16-35mm L (landscape, events), Canon 24-105mm L (landscapes, walkaround lens, video), Sigma ART 50mm (detail shots, occasional portraits)
Drone - DJI Mavic Pro with 4 batteries, tablet holder, remote
ND Filters - 2 stop, 4 stop, and 10 stop Hoya 77mm ND filters

Basically an entire mobile studio ready for anything from weddings to light video work to landscapes to portraits fits in this bag, not to mention the Mavic Pro for aerial photography and aerial video. Unfortunately the bag is so full at this point that all of the various chargers (laptop, Mavic, Canon), and associated wiring simply do not fit, but for a day trip this bag has it all. The other thing that does not fit is off camera flashes, but when shooting an event that needs flashes I'd bring a lot more equipment than this (diffusers, light stands, radio triggers, etc).

PROS
Space - Of course the number one PRO is that this thing holds almost everything I want to put in it. I would love to be able to add a flash and small flash diffuser so that I'd be equipped for impromptu portraits with on camera fill flash, but I'd have to remove a lens or the Mavic Pro for a flash to fit.

Build Quality - So far the build quality has impressed me, I still feel like i am putting too much gear in this bag since the zippers and seams are straining a bit, and I am a little concerned because I could not find a clear warranty statement on the LowePro site, but if the seams pop or the zippers break hopefully LowePro will provide warranty support.

Size - for me the size is perfect. It's not quite big enough to need rollers, and it fits with ease into the overhead compartments on airplanes. I have noticed that when you have a backpack on your back at airports the airline attendants ignore you; the minute you are pulling a carry-on with wheels your chances of being allowed on the plane without checking your bag are about 50% even if it fits in the overhead.

Customization - the movable panels inside the backpack allowed me to customize it to fit my needs. When I am traveling I will have it setup to store the Mavic and Canon, when I am local I will set it up to support two camera bodies and flashes for weddings and events.

Usability - The top compartment access is perfect for a quick run and gun scenario, and my favorite part is that I get to keep my 70-200mm lens on the body.

Appearance - I do not like flashy gaudy equipment that draws people's attention to my gear. This bag is not big or flashy and keeps logos to a minimum which is the way I like to keep it.

Anti-Theft - Since the zippers are on the inside, if you are in a country or location where theft is a problem, this bag will keep your gear safe. I have seen some reviewers complain that a thief could use the top or side zippers to steal your gear. The solution is simple, if the location you are at is that bad, then simply ziptie those zippers closed. But come on people, if theft is really that bad, are you even going to bring this kind of gear? Personally I would bring the cheapest Rebel and kit lens I own.

CONS

Warranty Statement - I am having problems finding a clear warranty statement on the LowePro site, Amazon states the vendor has a limited lifetime warranty, but this is not apparent on the LowePro site.

Zipper Placement - I knew before I bought this bag that the zippers were on the inside, so I am not going to take away a star for this, but it still takes some getting used to. I liked being able to hang my bag on my light stand and having access to the contents of the bag; with this bag I have to lay it on the ground to get to it through the rear.

Rain Cover - I am not sure if this was supposed to come with the rain cover, I thought I read somewhere that the rain cover is included. I am going to contact the manufacturer to see if this was supposed to be included.

CONCLUSION

This bag is exactly what I was looking for, I only hope the zippers and seams last a long time because they are definitely stretched to their limits holding all of the gear. The bag is pretty comfortable to wear, I went up and down a pretty steep mountainside with no problems from this bag. This is the first camera bag that I have owned where the zippers are on the inside; that is taking some getting used to, but I guess one benefit to this is that if you sit it in dirt the dirt will not be all over your back when you put it back on your shoulders. The downsi

This is a great quality product. Very functional and highly customizable to meer your needs. The materials used are first-rate. Excellent fabric inside and out. The zippers are heavy duty. Very easy in the shoulders and on the back. Will hold a long telephoto lens and a couple of short ones plus the body. Nice touches including the multi straps that run along the body of the bp, pockets, four access points to the interior, plus other attachments that makes things customizable. I had slings and this is way more comfortable.