Decide what the photograph must show
A portfolio detail and a wide introductory image have different jobs. The first may need enough resolution to show material texture; the second may only need to establish the room or subject. Exporting both from the same large file without considering their use can waste data.
Start by identifying the essential detail. Is the reader looking at a joinery junction, a person’s expression or the relationship between buildings? That decision should guide the crop and display size before compression settings enter the conversation.
Give the browser suitable choices
Google’s web.dev guidance explains how responsive image markup can provide several image sources and information about their displayed size. The browser can then choose an appropriate file for the device and browsing conditions. This is more flexible than sending one oversized photograph to every screen.
For a site owner, the useful question for a developer is straightforward: does the page deliver smaller files where appropriate, or merely shrink a large image visually? A picture that appears narrow on a phone can still require a large download.
Check the crop as well as the file size
A desktop composition may lose its subject when squeezed into a tall mobile frame. If the same crop works at both sizes, keep it. If it does not, consider a deliberately selected alternative crop. web.dev distinguishes this kind of source control from simply offering different resolutions.
Keep the photographer’s credit and any necessary context attached to the image. Write alternative text around the photograph’s useful content rather than its filename. A building’s location belongs in the caption when it helps explain the story; a string of search phrases does not.
Compare the exported result
Review the original and the published image at the size visitors will actually see. Look at edges, faces, gradients and areas of fine texture. A smaller file is not an improvement if it destroys the detail the story needs.
Then load the finished page on a phone and check the full sequence of images. Remove near-duplicates that add no information. Keep original files separately so future crops do not depend on an already compressed copy. The aim is a considered set of photographs that arrives efficiently and still explains the work clearly.
