Tag: painting

A tale of security and digital watercolor

Well, looong time no see. I’ve been having a bit of a health related crisis, nothing serious in the sense of being (potentially) fatal, just very painful and persisting for a long time.

I have actually been drawing and painting some and might go pack and catch up on some of the better ones here, but for now I want to talk about “Rebelle 7 Pro”.

I’ve been aware of it for quite some time now but never had the hardware to run it on, but now that I’m returning to work and entering a new phase, my employer insisted very strongly suggested that I stop working on my private Linux machine and bow to the demands of corporate security and certifications of such.

As annoying and most of all time-consuming that change was, it also opened up new possibilities.

A very fancy Macbook enters..

Now I had a very fancy new Macbook Pro Max and immediately thought: “Ey, ich sollte auf dem Ding echt mal Rebelle probieren!”.

But it turned out It wasn’t just going to be “trying-out-Rebelle-on-that-thing on a boring sunday” situation. For egonomical reasons, actually working on a laptop was out right out of the gate. I’m far too old (and achy) to do things like that on the regular.

With the Wacom Cintiq on the arm, my desk has become somewhat of an immovable object and I have no other and currently no place for one anyway, so…

The solution I came up with works quite well in practice, even if it looks jerry-rigged in parts: I just disconnected the Wacom from the Linux machine and connected it to the USB-C based laptop station that came with it. So switching it back is just replugging an HDMI and big USB in theory, but I never once switched it back since.

I control both machines with “Synergy 3” which allows network mouse sharing almost as seamlessly as using two monitors on one machine. I arrange it so that my former main monitor is rotated a bit to the left and I rotate the Wacom a bit to the right and then I can just move the keyboard and rotate my chair accordingly.

Painting in Rebelle

I have always liked the way Rebelle looks, both in finished paintings as well as watching videos of the process. I have always *hated* watercolor brushes in every painting program. They provide shitty implementations of watercolor process artifacts without providing anything like the way painting works in watercolor. They just feel like a mockery of something very beautiful.

But with Rebelle it was clear to me from the first look at it that it was different. Not only do the results look like watercolor, the process seemed kinda similar, too.

Another thing I was eager to try out was the oil paints in Rebelle. Due to my atopy I have a very hard time with a huge number of chemicals and it is very questionable whether even the mildest real oil paint and thinners etc pp would be even remote tolerable for me.

Rebelle Watercolor: A steep* learning curve

I will spare you my first attempts at Rebelle Watercolors since there was quite a bit of learning and getting used to it ahead of me.

But I persisted and quickly discovered what I was doing wrong. I expected the watercolor brushes to work, well, like real life watercolor does. But they don’t and I think rightfully so. It is really rare that I actually want to use the trademark watercolor artifacts like cauliflowering/run-backs in my real media art. Mostly I spent a lot of time learning how to avoid them.

Where Rebelle differs from real life watercolors is exactly those areas. Rebelle Water™ does not work exactly like H2O.

My working theory on Rebelle Water™

So Rebelle has two kinds of water in a way. There is the water tool which applies kinda puddles of flowy water which rewet colors and which might also form running droplets if you configured Rebelle that way (Enable in “Visual Settings” and then activate “tilt” to actually make it run).

You can apply on a “dry” canvas as well as on a “wet” one.

(* a steep learning curve is a good thing. If you plot current skills over time, a steep curve means that you learned a lot in a short time. It’s not a physical mountain.)

Wetting

And then there is wetting via the menu above the layers view. Both create wet surfaces, but can work on selections and stencils, but the menu creates kind of a minimal covered surface where every nano-pixel is either wet or dry but contains a minimal amount of water.

Rebelle Water™ Behavior

But in the end it does not really matter how much water there is on the canvas, as long as it does not flow. The result of applying a new watercolor brush stroke is not some complicated interaction with canvas water levels and water amount in paint and capilary forces and whatnot.

In real life watercolor, I have to carefully consider paint consistencies and rank them in levels, commonly named after traditional non-vegan food (cream,milk,tea,water). You generally work light to dark but you don’t need to do strict phases. If I have a color on an not-quite-dry real life canvas, I can “drop in” a thicker color and it will blur out a bit depending on the drying time I used. This is very useful for color variations within a wash.

But in Rebelle, the outcome of the new brush stroke is determined by the amount of water in the new color. If I try to drop in a color with the water slider all the way left it will just sit there if the canvas is just wet. Only when I added lots of water with the water tool and the water I added first is running, then the dry color on top will run with it.

The water level of the new brush stroke controls how much it flows basically. I can set the water to the level of blur I want, I stop time/”pause diffusion”, paint the brush strokes I want in all the colors I want and then when I unpause time it will all start to flow into each other and there will only be run-back if I carefully engineer it with the blow tool.

You can watch the diffusion happen in real time and if you don’t like it at any point, pause time again and undo. The last state before you unpaused time before will be restored and you can make changes to the settings, granulation, and tilt to run it again differently.

Abstract piece I did with Rebelle watercolor and a tiny bit of airbrush

Painting Session Recordings

Painting Session Recordings are really cool. I always wanted to try it out but something held me back or something or I painted something and then thought “Dangit, I could have recorded that.”.

But one time I accidentally had recording on and the result from the painting above is super cool and also fun to watch.

Since I had no idea I was recording, I had to stitch this together from multiple vids, but the result is really nice.

Recent Paintings and Drawings

For some reason I have mostly documented my digital painting and old ink work here. Most likely because I wanted to document the bursts of Inktober related drawings while the watercolor paintings lack both such bursts but also an easy to grasp arc, interpunction in the flow of art.

I really should keep this more up to date. I always look back and there’s so many stuff I might have posted here and there on twitter and some chat channels but without leaving really any trace but for the selected few people that get entry to my makeshift studio and see all crap, mostly non-digital now.

Anyway, here are some recent things that seem not all bad at the current point in time.

Landscape and other paintings

Landscapes and cats, mostly 😄. The CC-based paintings are based off creative-commons licensed photos.

Made on request

Paintings I made for either /r/redditgetsdrawn/ or /r/characterdrawing/.

Inks

Some pretty dark and somewhat personal inks. I’m kinda torn about such things. On one hand it’s really private and I don’t really want to talk about it beyond this artistic/symbolic expression, but not surprisingly, they also feel like very strong pieces.

Watercolor Projection process

Painting with light (AI generated)

I thought I document the process I figured out for myself of how to best approach doing watercolor painting based on digital sketches with the help of a DLP projector.

Background

I have been working on my painting skills for some years now and ended up in a on/off relationship with watercolor. Did not like acrylpainting, did a limited amount of gouache painting and kept coming back to watercolor even though it made me quite mad at times.

One of the things I was very dissatisfied with was using pencil to sketch out my paintings. It was always a struggle to draw faint enough so that the markings wouldn’t bother me in the final result and also a lot of losing shapes and lines in the heat of things.

While I made my peace with watercolor not always coming out like you want to, it kept bothering me how I would also lose my sketch and had to start over from zero to redo a painting.

DLP-Projector

I discovered DLP (Digital Light Processing) projectors by accident in a youtube video. I wasn’t even aware that the technology existed and that it allows for devices that are very different from your clunky old projectors. The “digital micro mirrors” basically allow for fine-controlled projection that isn’t straight forward.

I ended up buying a “EKASN Mini Smart DLP Projector” which no longer seems to be avaible, which sadly often seems to happen, but I imagine that other devices based on the same DLP chips will work very similar.

My projector runs “Android TV” as operating system which offers a lot of options of how to get images on there, but in the end, the installed File explorer thing comes with a Browser based upload thing (with Chinese UI 🤣) that seems to work best.

Starting a Painting

When I want to paint a painting, it starts with the paper I want to paint on. I usually work with watercolor paper blocks, so I chose the texture and size I want.

So let’s say I use Arches cotton paper, 31cm x 23cm. That means I create a new image that has a nice big resolution that works well on my Cintiq. Usually I chose the larger dimension to be 1920 which is the FullHD width and also a good fit for the height on my screen with enough room on the left and right for palettes, toolbars and references and whatnot.

So for the Arches 31cm x 23cm in landscape format and a target width of 1920 pixel, we need a height of 1424px (1920 x 23 / 31). I usually tape my paintings to have a nice white border in the end, so I include that in my template and use the area for some simple projection markers.

One of my painting sketches with references

Here I created a border for the painter’s tape I have which is 18mm wide. You can download the empty template in OpenRaster-format below. (I use OpenRaster so I can have a multi-layer image I can open in Krita as well as Gimp).

The example above has multiple sketch layers. For one the handdrawn sketch and then a layer with black at a low opacity where I planned the shadows for the scene.

When I do the shadows, I duplicate the shadows and use an edge filter to get the outlines for it, too. Then I save two different images. One just with the lines and one with the shadow layer.

Preparation

Once I’m ready to start projecting, I save the projection images as PNG and run them through my preparation script.

#!/bin/bash

if [ -z $1 ] || [ -z $2 ]; then
        echo "Usage: c900prepare <image> <output>"
        exit 1
fi

# scale to c900 native resolution, rotated if needed
convert $1 -rotate "90<" -scale 1280x720\! $2Code language: PHP (php)

This is a linux shell script using ImageMagick and the last line is the most important $1 is the input file here and $2 the output file.

If this all sounds to complicated for you, the basic idea of the command is that I scale down my projection images to the exact native resolution of the projector (1280×720). This scaling disregards the correct aspect ratio of the image and stretches it to fit. What the script also does is take care of the orientation. 1280×720 is obviously landscape format, but sometimes I want to project in portrait format that is higher than its wide. So this command rotates the image by 90 degrees if it is portrait format so that the former top of the image is to right which seems to be the easiest way to setup my projection equipment.

Setting up the projection

My watercolor working space

So I have my table top easel where I can adjust the angle, sometimes I work at an angle like this for controlled washes, sometimes I work flat. I bought these photography arms that I assembled to this McGyver-ed configuration. This way I can adjust my arms in all kinds of directions. I usually try have the projector a good length in front of me so that it doesn’t project downwards and I am always shadowing what I paint. By projecting from the front the shadows fall towards me and the area under my brush is as illuminated as possible.

As you can see the projection comes from quite an angle at the paper, but it still perfectly hits the square of it. The manual projection adjustment allows each corner of the projection to be moved pixel by pixel until it matches the canvas.

How to adjust the projector

The projector position should be made to fit the paper as good as possible. Reset the projection if necessary and put the projector at a distance where all four corners of the paper are in the light. Make sure the image is centered on the paper.

Now use the projection adjustment to move the corners inwards until they match the paper. I usually adjust it so that the light creates a bit of shine outside of the paper and then adjust that so that the shine has the same brightness along the whole edge of the paper. This seems to be more precise than trying to have the slightly fuzzy projection edge match the paper edge (Arches paper also has a black binding which makes that even more difficult).

This process fixes the disregard of the aspect ratio in my preparation step as it stretches the projectors native resolution back to the aspect ratio of the paper I started out with. If I did my math right, the lines I draw around the image in my template match exactly with the inner border of my tape and the little projection marker boxes fill out the corners.

Conclusion

I really like to work this way, it allows me to work digitally on my sketches and move things around, scale them, copy and paste parts, whatever, the full digital convenience. If I fail to paint how I want, I can always restart with the same projection sketch. For some of my paintings sometimes I do three or four attempts.

It is no silver bullet. The projected lines are pretty strong if maybe a bit low resolution sometimes. It is still possible to get lost. Especially when I’ve already laid down the darker paint it can be hard to see the lines. I often flip back and forth between the projection image and an empty white image which can help to find lost lines. At some point it is just best to just let go of the projection and just work with the painting. I also have another android tablet for reference images. Mostly for color reference, but I also copy the projection image over to keep working with it while not actually projecting.

References

D&D characters

I often don’t actually post my paintings here, which I totally should. Here are some character paintings I did people in /r/characterdrawing

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