How do I change one thing in a product photo without regenerating the whole image?

Pick the method by what "without regenerating" has to mean for this photo. If no pixel outside the change may move, select the area and fill only that selection in a tool such as Photoshop Generative Fill, Photoroom Retouch or Product Fixer, or Canva Magic Edit; to widen the frame, use an expand tool that fills only the added canvas. If you mean "without starting over", and the change has to be worked into the whole photo, such as the same product in a new setting, a garment on a model or a product placed into an existing scene, start from the photo you already have in Nightjar Edit Images. It keeps the photo's product, framing and shape as the starting point, lets you point at the image that supplies a new scene or garment, and returns the result as a new image beside the original.

When should you use a selection tool?

Use a selection tool for a small local fix where everything outside that area must stay as it is: a dust speck, a price sticker, a stray prop or a small damaged patch of background. A selection tool replaces only the area you select, so the rest of the file is untouched by the edit.

• Photoshop Generative Fill: you select an object or area with the Selection Brush or any other selection tool, then describe the change, or leave the prompt blank and Photoshop fills the selection from its surroundings. The result goes on a separate Generative Layer "for nondestructive editing of your original image". For a wider frame, Generative Expand lets you drag beyond the image borders with the Crop tool and fill only the extended canvas (Adobe).
• Photoroom Retouch: you brush over an unwanted object to erase it. Photoroom describes it as a free utility that does not use AI credits (Photoroom).
• Canva Magic Edit: you brush over or click an object, then describe what to add or replace in the selected area (Canva).
• Photoroom Product Fixer: for one wrong product detail on an otherwise finished AI image, such as a logo, texture or missing part, you paint over the area and supply a photo of the real product. Photoroom says it "redraws the selected area of the image, matching it more closely to the product image(s) you provided" (Photoroom).

A selection controls where the change happens, not whether the new content is right, so still check the filled area closely. The inpainting answer covers how large to make a selection and how to review it, and the object removal tool comparison helps you choose a tool for removals.

When is Nightjar Edit Images the better route?

A selection limits where pixels change, which is the right control for a local fix. Some changes are not local. A new setting changes the light falling on the product and the shadow under it, so the product has to change along with the background; cutting the product out and swapping the background keeps its pixels, but also the light it was shot in. A garment on a model has to follow the body's pose and folds. A product placed into a scene you already have has to take on that scene's perspective, scale and light, and cast a shadow that fits. In these edits the hard part is making the new content agree with the rest of the photo, and a tighter selection does not solve that.

When the change has to be worked into the whole photo, such as the same product in a new setting, a garment on a model or a product placed into an existing scene, Nightjar Edit Images is the stronger route. It starts from the photo you already have instead of a new shoot: open an Asset's Edit action and that image goes straight onto the Edit board, with no export or re-upload. The output keeps the first image's shape, at the nearest supported aspect ratio, unless you ask for another. When the change comes from another image, add it to the board and name each image's role in the instruction with @image1, @image2 and so on, up to eight images, so "this product, this scene, this garment" is stated rather than guessed.

Nightjar also writes the final instruction so the change and the parts to keep are stated separately, and its built-in visual review checks the result for obvious failures, such as a requested change that is plainly missing or a product that no longer matches, and can retry at no extra Credit cost. The result is saved as a new Asset in your Team's Library beside the original, ready for comparison, another attempt, Upscale or a Photoshoot.

Recolor and Reframe are different, because a selection or expand tool can do them without moving anything else. A masked recolor in a selection tool keeps every other pixel fixed, which is why the color answer recommends a mask when surrounding pixels must be protected. An expand tool such as Photoshop Generative Expand keeps the original pixels and fills only the new canvas. Nightjar's Recolor needs no selection to draw: the source Asset shows the product, you name the surface to change in words, /color makes the target color explicit, and the result stays in your Library with the original. Nightjar's Reframe produces a new frame at the new ratio rather than extending the old one, so it suits a photo you are already working on in Nightjar or a reframe combined with another change. The color answer also covers recolor steps and color proofing. /format sets the file type of an edit you are already making; to change only the file type, export or convert the file, which needs no generation.

Nightjar Edit has no mask, brush or selection. It re-renders the whole frame from your source and instruction, so parts of the photo you did not mention can shift, and its review looks for product failures rather than background changes. When approved pixels must not move, use a selection tool, an expand tool or a layered composite instead. The two methods also combine well: make the product-aware change in Nightjar, then use a selection tool for any small local fix that remains.

How do you change one thing in Nightjar?

Each kind of change has a natural starting point in Edit and a few details worth naming as fixed.

The product placement guide covers fitting a product into an existing scene in more depth.

1. Open the photo in Edit. From Assets, choose Edit on the image. That puts this one image on the board and opens the Edit tab. You can also open Generate > Edit and add images under Images to Edit by uploading or picking from your Library.
2. Add any image the change comes from. For a new scene, garment, person or color swatch, add that image to the board too. Type @ in the prompt to reference each image.
3. Choose a shortcut or write the change. An Edit Shortcut pre-fills a common instruction, such as "change the color to" for Recolor or "place the product from @image into the scene of @image" for Product Placement. Resolve every placeholder before you submit.
4. Say what must stay the same. Name the parts that matter most, especially the product's shape, label, logo and finish, and the crop.
5. Compare the new Asset with the source. Check the change you asked for, then scan the rest of the frame at normal size and close up. If something you wanted kept has moved, name it in the instruction and edit the original source again.

For example, an illustrative instruction for a new setting could read: "Move the ceramic mug in @image1 from the white background onto a light oak kitchen counter with soft window light from the left. Keep the mug's shape, glaze, handle and printed logo, the camera angle and the crop unchanged." It names one change, the product it applies to and the details that must survive. For readable packaging text, the text and logo answer explains what to check before you publish.