https://ebiketips.road.cc/content/news/utterly-brilliant-an-interview-with-timmy-mallet-on-all-things-e-bike-2343
He said
I was carrying 25kg in my panniers and painting gear
I found it quite liberating to have a limited set of everything. Clothing, my paints (although these won't be essential for everyone!) and that's about it.
One person's idea of having a limited set of everything may differ from another's!
If he was not camping 25kg includes a lot of painting equipment.
You'd be surprised, Mike, both at how low a painter can go if he's innovative and adaptable, and at how hefty traditional painting gear can be.
Mr Mallet is a painter in oil and acrylics, which weightwise is six of the one and half a dozen of the other. He seems to have made a pochade box (the pochade is the onsite or plein air painting that you paint in a pochade box, so both words are required to describe the container) out of a cardboard box to save weight. I imagine his box of paint, brushes, necessary liquid medium and liquid cleaning solvents weighed a minimum of 7 to 10kg, probably more.
By way of comparison, I inherited my teacher's pochade box for 16x12in plein air landscapes. This is a wooden suitcase about 18x14x4in with internal structure and ribs for holding the painting boards (2) and palette in the lid. With traditional painting equipment inside it, it is atrociously heavy, not my idea of fun lugging such a deadweight up a hill. I've made it tolerable by assigning it to the lightest weight of my various oil-painting kits, which uses oil bars in wax, and which I paint with silicone tipped instruments or painting knives, all of which wipes clean, so no liquids are required except a small bottle of water for washing barrier cream off hands. With the 2.5kg or so of a Manfrotto professional photographer's tripod to put the pochade box on, and a stool, and a hefty canvas bag for stones added on site to stabilize the tripod, you're easily up 25kg.
Trying to make that kit lighter still, I packed about half as many oil bars and tools into a toiletries bag, and substituted a lightweight sketching easel in wood for the Manfrotto, and an aluminium shooting stick for the stool and now you're at something over 10kg. You can go quite a bit bigger than 16x12in on this setup but only on windless days.
(http://coolmainpress.com/andrepaintings/andre_jute_country_plein_air_kit_1.jpg)
The photo shows a lady's messenger bag I used before I scored the more convenient big toiletries bag I now use off a lady pedaliste. The brown leather saddlebag is permanently on the bike to hold weather jacket, a bar of Bournville chocolate, suchlike. The pannier basket is Basil's Cardiff model. The stainless steel rack is a Tubus Cosmo.
(http://coolmainpress.com/andrepaintings/andre_jute_country_plein_air_kit_2.jpg)
Ready to paint, easel erected, board fitted, supplies bag open and hung, shooting stick seat lounging elegantly.
(http://coolmainpress.com/andrepaintings/andre_jute_kilbrogan_fields_2014/andre_jute_kilbrogan_fields_2014_oil_on_canvas_10x8in_800pxh.jpg)
The resulting painting. Faux Tuscan!
The lightest oil painting kit I've made is limited to 8x6in. It's a Jullian of Paris pochade box, like a miniature version of the one above, but not the metric model Jullian itself sells which is limited to their overpriced metric boards, but the one they made for Utrecht in the States to imperial measures for which you can get a big range of boards. It suffers the disadvantage that you have to use 21ml tubes of paint rather than the normal 37 or 40ml size, and the small size is hard to find and expensive. On the other hand, it is so light you don't need a stand, you hold it on your thumb through a hole in the bottom of the box, and paint with your other hand.
Generally speaking, the experienced bicycle painter doesn't take the heavy gear with him unless he's scouted out the vista to be painted with it. The only kit permanently on my bike is a tin that holds 6x4in postcards, a watercolour paintbox the size of a visiting card, a couple of water brushes (they're like fountain pens, with the water in the barrel and a brush at one end) and that's the whole thing.
(https://www.parkablogs.com/sites/default/files/andre-interview-03.jpg)
Here's a slightly bigger version of the postcard pochade box, with the Bijou paintbox open, real if small water containers (filled out of my bike water bottle), and a collapsible sable brush.
I also have a big leather bucket bag with a 6x8in sketchbook inside and large variety of small kits so that a wide range of multimedia art can be demonstrated on group outings. It weighs about 10kg, so it is too heavy to cart around on solo outings on the off-chance that you'll see something that fits one of the sketch kits in the bag -- more likely that you'll see several opportunities for art for which the bag holds no equipment...