Adding weights to prompts can be handy for telling the Midjourney bot which elements of the prompt are important to you or what you don’t want to see in an image. This allows you to fine tune your Midjourney prompts and achieve images which are more closely aligned to what you have in mind.
This takes some experimenting with and the results may sometimes be surprising! However, learning how to add weights to your prompts will (hopefully) allow you to fine tune your promptcrafting for more consistent results.
How to Add Weights
When adding weights to prompts, we split up the prompt into its key components using :: Therefore a prompt could look like this:
a large unicorn :: with a rainbow background :: –ar 4:3
This is telling the Midjourney bot that both the large unicorn and the rainbow background are of equal weight (the –ar 4:3 is giving the ration ).
What Is Weighting in Midjourney Prompts?
Weighting allows us to break up a prompt using :: as we saw above and give weights to different elements. The weights are proportional. If I were to write red::1 blue::0.5, Midjourney bot would read that as blue being half as important as red.
The default is 1, therefore if I were to write red:: blue::0.5 it would have the same effect as above.
Negative numbers can be used too. This has the same effect as using –no.
Let’s look at this in practice (obviously I have chosen the images below because of what they demonstrate – not necessarily because they are aesthetically pleasing!).
Prompt: A drawing of a rainbow
As you’d expect, this prompt returned a colorful rainbow.
Prompt: A drawing of a rainbow :: blue::1 Pink::-1
Here I added weights to the end of the prompt to produce a rainbow which was blue with no pink colors.
Using Weights in Prompts to Generate an Image of a Blue Tomato
In the example below I have used weighting to get Midjourney to create an image of a blue tomato. I started with a base prompt and then varied it. You will see the results below.
Prompt: A photorealistic image of a tomato
This is the base prompt. Here I prompted ‘a photorealistic image of a tomato’ and unsurprisingly, I received four red and relatively normal looking tomatoes in return
Prompt: A photorealistic image of a blue tomato
I added ‘blue’ to the prompt and you will see from there results that Midjourney tried to create a blue tomato, however all the information it is trained on is telling it that tomatoes are red! You can see it is struggling to create a blue tomato.
Prompt: A photorealistic image of a tomato ::1 blue::1 red::-1
I used the base prompt and added weights. By adding blue::1 and red::-1 I was effectively saying that I wanted the image to be blue and for there to be no red. Was it successful? Well I certainly got more blue tomatoes than in the prompt above.
Prompt: A image of a tomato ::1 blue::1 red::-1
Out of interest, I reran the prompt removing the word ‘photorealistic’. I’m not sure that there’s much of a difference although perhaps the tomatoes are a better shape in the with ‘photorealistic’ included. But colorwise they are pretty similar.
Using Weights With Styles
Weights come in very handy for having some control over styles. For example ‘a cat by Picasso‘ will give a cat painted in the style of Picasso. But what if I want just a small influence of Picasso in the image? This is where weighting appears to really come into its own.
Let’s look at cats and Picasso!
Prompt: Cat by Picasso
This prompt ‘cat by Picasso‘ returned a cat in the style of a Picasso painting.
Prompt: Cat :: Picasso::
This prompt is in two parts with equal weighting.
Prompt: Cat :: Picasso::.5
This prompt weights the cat as 1 (1 is the default) and Picasso as .5. We can definitely see less of a Picasso influence in these images.
Prompt: Cat :: Picasso::.1
This prompt weights the cat as 1 (1 is the default) and Picasso as .1. There is just a small influence of Picasso in these images.
Is Weighting Always The Best Way To Go…?
In my experiments and practice runs I’ve found that prompt weighting works great in some instances but might not work best in others.
Certainly using weights to add a little sprinkling of a style into the mix is extremely effective and allows us to remix and create new styles.
However, sometimes just rewording a prompt can have a better effect.
For example, using the ‘hot dog’ example which is given in the Midjourney training documentation, I’ve found that using weights doesn’t allow me to create the canine version of a hot dog (ie a dog, not the food). I can just about get to a dog using weights, but it’s not quite right.
In the examples below, even though I tried various weights (ie sausage:-1 dog::1), I was unable to really get an image of a hot (canine) dog.
However, simply changing the words a bit to ‘a dog that is hot‘ with no weighting gave me much better results:
and just for reference, I ran the prompt ‘hot cat‘ and got the same vibe as ‘a dog that is hot‘ above, which shows that hot dog food didn’t influence the new prompt.
YMMV, however for me, I find that prompt weights are super useful for varying styles . A bit like you would alter the proportions of seasoning to make the perfect curry, so we can vary the reference of styles to create the perfect new style for an image. However, I believe it’s important not to over complicate things. Very often just a change in words will help.
- Think about how you would describe what you have in mind to someone else
- Remember that Midjouney will take what you say literally
- Be as detailed as you need to be – ‘hot dog’ is always going to be a tricky one, however if I develop the prompt to read ‘a cartoon dog which is sat in a hot sunny desert’, I get a much better (in my eyes) image