I've been combining hiking and painting for a couple decades now and have come up with a lightweight system to carry wet canvases (boards), and the easel a few miles from the car.
Pastels have been my main medium until this fall, when I switched to oils. I bought the Raymar wet canvas carrier, and it is ok, but my boards were a little too thick for it. I started out painting on 3/16 inch plywood left over from lining my truck bed.
So, rather than ordering more from Raymar, I made my own, and made them a skosh wider to accomodate both standard 1/8 inch Masonite (MDF) boards, and the 3/16 inch furniture grade plywood, both of which can be found at Home Depot.
If you have ever tried to backpack several wet paintings, you know that you basically need a shelving unit, with the paintings being the shelves that slide in and out. They should only touch the shelving unit (wet canvas carrier) on their unimportant edges...preferably only the outer 1/4 inch or less.
Home Depot has 1/4 and 3/8 inch square "dowels" in lengths of 3 feet. I used the 1/4 inch size to make rails for my 12 x 16 inch carrier.
I figured the 16 x 20 inch size would be more likely to sag, so I used thicker rails there ( 3/8"). But I didn't want the rails to mark the painting any more than necessary, so I rounded the 3/8 inch rails with a rasp file. I glued the rails in with wood glue, and short nails, pre-drilling the "dowels" so they wouldn't split. I used oak for the side frame.
The big 16 x 20 inch wet canvas carrier weighs 3 pounds empty, and it can carry 8 paintings.
This big box may turn out to just be a storage box in the car for wet paintings. I may still try to figure out a way to carry 2 big boards face to face in my backpack. I'm thinking about some kind of 4 cornered elastic thing that holds two wet paintings face to face, rigidly without allowing them to touch.
This is my 16 x 20 box, 3 pounds empty including lid:
In case you've never seen one of these, in the wider slots (1/2"), you put two wet paintings back to back.
As you may be able to see here, I used 3/8 inch wood rails, glued and nailed in place every 1/2 inch. I also left a 1/4 inch gap for a single painting on the outer edges, for a total capacity of 8 wet paintings. I'm hoping the paintings themselves can form the outer sides of the box, but if not, I may glue on some outer plates of 1/2 inch foam core.
The photos below show my 12 x 16 inch box. I made it big enough to handle 12 x 18, and built an adaptor to make it work with 11 x 14 as well. I got this idea from Raymar, and the other wet canvas box makers who all sell adaptors.
I use a full size carbon fiber tripod called the Gitzo Mountaineer GT-0531. It weighs 1.6 pounds without the ball head. It is amazingly rigid, but priced accordingly around $500 if you can still find it. I bought it back when I was working full time in web design.
With any camera tripod, you need a shelf. Since this is thin walled carbon fiber, I decided the shelf should attach to the metal head where the tripod is strongest.
I like to mess around with sheet metal and drill presses, so I built a little clamp on shelf pictured below:
I had an old steel Italian easel sold by Daniel Smith from last century. I loved the way it allowed me to paint any size from 5 x 7" up to 24 x 36". But those steel legs had to go, too heavy!
I took just the important part (slider bar with painting clamps) and mounted a 1/4" aluminum plate that would allow it to connect with the quick release plate on my Manfrotto ball head. I drilled and tapped several holes of 1/4 x 20 in case I stripped one out in the field.
The whole easel, which weighs 4 pounds ready to paint. This thing is solid, no wiggles at all:
I plan to give this new oil painting system a work out in the coming weeks. Painting indoor still lifes and portraits is fun, but I much prefer working outside in the sunshine.