Runway Gen-4 Sketch References for Product Images

A product seller often asks one AI prompt to do two different jobs: preserve the exact item and invent an attractive composition around it. When the layout changes, the product can change with it. A bottle becomes wider, a bracelet moves to a different angle, or the space reserved for a headline disappears.

Runway Gen-4 Image offers a useful way to separate those decisions. Its References workflow can combine a real product photograph with a rough sketch or annotated layout. The product photo supplies the subject. The sketch tells the model where that subject, props and empty space should sit.

This is not proof that Runway will preserve every SKU perfectly. Its official examples are mostly creative and character-based, not an independent product-fidelity benchmark. But the control method is practical enough to test when a text prompt keeps producing the wrong composition.

Why a sketch can beat a longer prompt

Text is good at describing mood, material and lighting. It is less precise when you need a product to occupy a particular part of the frame while leaving clean space for copy. “Place the bracelet in the lower-right third” still gives the model room to interpret scale, rotation and distance from the edge.

Runway’s sketch tool lets you draw shapes, arrows and text labels over an image or on a blank canvas. Its documentation says sketches can control composition and object placement. A separate advanced guide recommends simple rectangles, circles or other labelled shapes to define boundaries for elements in the scene.

For an ecommerce creative, that means a rough rectangle can reserve the product area, another can mark a prop, and a blank block can protect the area where a designer will later add real text. The sketch does not need to look polished. It needs to make the spatial instruction unambiguous.

Build two references with two clear jobs

Start with the best available product photograph. Use even, natural lighting and a clear view of the item. Runway recommends neutral, evenly lit reference images because they give the model a less opinionated starting point. For a product, the same principle helps reduce conflicts between the source lighting and the new scene.

Next, create the layout at the final aspect ratio. If the advert will be square, sketch a square. Draw a box for the product and label it “product”. Mark any surface, hand, plinth or prop separately. Leave a clearly defined empty region for the headline, price or call to action, but add the final typography later in a design tool.

Save and name both references. Runway supports up to three active references in one generation and allows saved references to be tagged for reuse. Give each input a functional name such as product and layout, then refer to those names in the prompt.

Keep the prompt descriptive and positive. Runway’s prompting guide says negative prompts are not supported and may produce the opposite result. Instead of writing “do not change the bracelet and do not add stones”, describe what must appear: “Commercial studio photograph. The exact polished stainless-steel cuff from product appears in the position and scale shown in layout. Clean pale-grey set, soft light from upper left, realistic contact shadow.”

Run one controlled batch before adding more instructions. Gen-4 Image provides an Aesthetic Range setting from 0 to 5 and a configurable seed. A low aesthetic range is the sensible starting point when layout control matters more than creative variety. Saving the seed also makes comparisons more disciplined, although neither control guarantees SKU accuracy.

Use the third reference only when it has one job

A third slot can carry a lighting or style reference, but it should not become a second product brief. Runway says multiple references can offer more precise control over individual elements, while also warning that every new variable creates more opportunity for results to diverge from the original vision.

The safest division is simple: one image for product identity, one sketch for composition and, only if necessary, one image for visual treatment. Do not use a busy campaign image as the style reference if it contains a competing product, model or logo. The model may borrow more than the colour palette.

If the first result is close, reuse that output as a new reference and change one element at a time. This follows Runway’s own advice for complex changes: iterate individual elements, then use the improved image as the next reference. It is slower than asking for everything at once, but it gives the seller a clearer point at which a product detail started to drift.

What to inspect before using the image

Check the product before judging the background. Compare the generated result with the source at high magnification. Look at silhouette, dimensions, clasps, prongs, stone count, engravings, logos, labels, openings and reflections. For jewellery, a slightly altered chain link or missing stone is not a harmless aesthetic variation.

Also check whether the sketch has leaked into the scene. Labels, boxes and arrows are instructions, but a generative model can occasionally interpret instructions as visible content. If that happens, simplify the sketch, remove unnecessary labels or break the job into two stages.

Runway currently documents 720p and 1080p output for Gen-4 Image across common landscape, portrait and square ratios. That is adequate for many ad concepts and social assets, but resolution does not fix an inaccurate product. Approve geometry and text first, then upscale or composite the final asset if the destination needs more pixels.

For a marketplace main image, conventional product photography or a clean cutout remains the safer default. A generated scene is better suited to secondary gallery images, adverts and campaign testing unless the product has been verified carefully and the marketplace permits the presentation.

A practical pass or fail test

Test the workflow on one difficult SKU before rolling it across a catalogue. Prepare one neutral product photo and three layout sketches: centred, rule of thirds and copy-led. Keep the prompt, lighting description, aesthetic range and seed constant. Only the layout should change.

The method passes if the three images follow the planned compositions while the product retains the same sale-critical details. It fails if each layout requires repeated prompt repair, or if the product changes enough that a designer would have to rebuild it manually.

The important lesson is broader than one model. A product reference and a composition reference solve different problems. Giving each one a clear role is often more controllable than forcing identity, styling and layout into a single paragraph.

Sources

Runway Gen-4 Image References guide, reviewed 12 October 2026: https://help.runwayml.com/hc/en-us/articles/40042718905875-Creating-with-Gen-4-Image-References

Runway Advanced References Use Cases, reviewed 12 October 2026: https://help.runwayml.com/hc/en-us/articles/41170686463635-Advanced-References-Use-Cases

Runway Gen-4 Image guide, reviewed 12 October 2026: https://help.runwayml.com/hc/en-us/articles/37053594806419-Creating-with-Gen-4-Image

Runway Gen-4 Image Prompting Guide, reviewed 12 October 2026: https://help.runwayml.com/hc/en-us/articles/35694045317139-Gen-4-Image-Prompting-Guide