2.1Essential parameters: format, exclusion, quality
The essentials in 30 seconds
- Parameter = end of prompt: two dashes (
--), chain several of them — format first, style after. - --ar for each medium: 16:9 landscape, 4:5 or 9:16 portrait/social, 1:1 square — generating in the right format beats cropping.
- --no excludes, :: weighs: chase the recurring element, dose the parts of the prompt — positive first, targeted exclusion after.
Running mini-case — Sonia and the poster that lost its margins
Sonia, freelance graphic designer in Algiers, is preparing a poster for a café in Algiers: she generates in default 1:1, crops to portrait afterwards, and the title added in retouching eats into the cup. She starts over differently: simple prompt + --ar 4:5 right at generation, clear space for the title, --no text, watermark to chase away stray letters. The image arrives in the right format, with no distorted text, and room for the title. This Algiers café poster returns in 2.2 (fidelity/aesthetics arbitration), 2.3 (image base + words), 2.4 (shared signature of the series) and 2.5 (scored and reused version).
Level 2 thread: Sonia's poster returns in the course, the diagram, the script and the 48h challenge — and continues in 2.2, 2.3, 2.4 and 2.5.
1. Parameter syntax
A parameter goes at the end of the prompt, preceded by two dashes (--), optionally followed by a value — and you chain several in the same prompt. Before touching style (section 2.2), three settings structure almost every image Sonia makes: format, exclusion and quality and pattern settings. Remember the working order: first frame (medium), then exclude (artifacts), finally dose (weights) — style comes after.
2. Format first: --ar
The most important one: --ar (aspect ratio) — --ar 16:9 (landscape, banner), --ar 4:5 or --ar 9:16 (portrait, social), --ar 1:1 (square, thumbnail). Choose the format for the destination medium, right at generation, leaving room for any text or logo. Why: Midjourney composes FOR the requested format (a 16:9 is not a cropped 1:1), and cropping afterwards throws pixels away. So Sonia generates her poster directly in --ar 4:5 with a clear area for the title.
3. Exclusion, quality, pattern, weights
--no excludes an unwanted element (--no text, frame): it is the equivalent of a negative prompt, a strong hint but not an absolute switch. --q (quality) sets computing time and level of detail. --tile produces a seamless repeatable pattern (background, texture). Finally, the double colon :: splits the prompt into weighted parts (futuristic city::2 rain::1 gives more weight to the city). Names, values and availability change with versions: Sonia checks the up-to-date documentation before reusing old parameters.
🔎 Concrete example — 🔎 Worked example — Framing for the right medium
Sonia's café poster, designed for portrait and the title added afterwards:
café poster, steaming cup, clean background, soft light --ar 4:5 --no text, watermarkReading: portrait social format, no stray letters, room left for the title.
Lesson: generate directly in the medium's --ar, don't crop afterwards (composition + quality).
Section vocabulary
- Parameter
- Setting placed at the end of a prompt, preceded by two dashes (--), sometimes with a value; chain several of them.
Simple example: Sonia ends her prompt with --ar 4:5 --no text, watermark.
What it is not: a word from the image story placed at the start of the prompt.
Reflex: every setting = end of prompt, with --.
- --ar
- Image format: 16:9 (landscape), 4:5 / 9:16 (portrait, social), 1:1 (square) — choose for the medium right at generation.
Simple example: Sonia generates her poster in --ar 4:5 for portrait.
What it is not: cropping afterwards, which throws pixels away.
Reflex: medium known = immediate --ar.
- --no
- Excludes an unwanted element (e.g. --no text, frame); a strong hint, not an absolute guarantee.
Simple example: Sonia chases stray letters with --no text, watermark.
What it is not: simply not mentioning the element.
Reflex: recurring unwanted element = targeted --no.
- --tile / ::
- --tile produces a seamless repeatable pattern; :: splits the prompt into weighted parts (term::2).
Simple example: Sonia tries --tile on a zellige pattern, then subject::2 background::1.
What it is not: two style or randomness parameters.
Reflex: pattern = --tile; priority = ::.
In practice — Hands on — Setting the essential parameters
- Generate the same prompt in three formats with --ar: 1:1, 16:9 and 4:5; watch how the framing changes.
- Add --no to remove a constantly recurring element (text, frame, watermark) and check the result.
- Try --tile on a pattern (foliage, texture) and see that it repeats seamlessly.
- Try :: weighting (subject::2 background::1) to give more importance to one part of the prompt.
Ready-to-use script — justifying format at generation time (30s)
'For the café poster, I no longer generate square and crop afterwards: I start in --ar 4:5 with the title area kept clear, plus --no text, watermark against stray letters. Midjourney composes FOR the requested format, and cropping throws pixels away. Format is set at generation — cropping is for minor adjustment.'
Say while showing the cropped 1:1 version (cup cut off) then the --ar 4:5 version (title in place).
Copy-paste template — poster calibrated for its medium
[subject], [context], [soft light], clear space for the title --ar 4:5 --no text, watermark
[landscape variant] [subject], [context] --ar 16:9 --no text, frame
[pattern variant] [texture] pattern, even repetition --tile --ar 1:1
[weighting] [subject]::2 [background]::1 --ar 4:5Café social post
Sonia generates the café visual in --ar 4:5 with --no text, watermark: the title added afterwards can breathe.
Page banner
Same subject adapted to --ar 16:9 for the cover: regenerate in the right format rather than trimming the portrait.
Menu background
Zellige pattern in --tile: Sonia tests seamless repetition for the menu background.
Tilting composition
The background swallows the cup: Sonia switches to subject::2 background::1 to give priority back to the subject.
✓ Best practices
- Choose --ar for the medium right at generation (avoid cropping afterwards).
- Leave room for text in the framing if a title or logo will be added.
- Use --no to chase one recurring unwanted element, combined with a clear positive prompt.
✗ Common pitfalls
- Generating in default 1:1 then cropping (lost quality and composition).
- Piling up parameters inherited from old versions without checking the up-to-date documentation.
- Confusing --no (excluding) with simply not mentioning an element.
Key takeaways
- A parameter goes at the end of the prompt (--); chain several of them.
- --ar sets the FORMAT (16:9, 4:5, 9:16, 1:1): choose for the medium, right at generation.
- --no excludes an element, --q sets detail, --tile creates a repeatable pattern, :: weighs terms.
- Names, values and availability change with versions: check the up-to-date documentation.
48h challenge — apply tomorrow
Take a real client visual (Sonia's or yours): generate it in 3 --ar formats (1:1, 16:9, 4:5), add a targeted --no, try --tile on a pattern and :: on a priority — then keep the version in the medium's right format.
- I can place parameters at the end of a prompt and chain several of them.
- I can choose --ar for the medium right at generation.
- I have tried --no, --tile and :: on a real case.
Frequently asked questions
Is it better to set the format with --ar or crop the image afterwards?
Set the format at generation with --ar: Midjourney composes FOR the requested ratio, cropping throws pixels away, and room for a title is planned at framing time. Cropping remains useful for minor adjustment — and extension features (Zoom Out / Pan, section 4.1) that generate new pixels are often better than plain trimming.
Does --no always work to remove what I don't want?
It is a strong hint, not a switch: it steers generation but an element induced by the rest of the prompt can resist. Combine a clear positive prompt with a targeted --no on one or two elements, rephrase if needed, and fix locally with inpainting (section 4.1) for hard cases.
What is the --ar parameter for?