Learning to develop

Learn Develop’s controls beside the photograph, with a field guide that explains what each adjustment does, what to try and how the processing works.

Press ? to show help buttons beside sliders and tool headers. Click a question mark to read an explanation; nothing opens merely because the pointer passes across a control. Develop field guide, above the process switch, opens a searchable index of adjustments and tools. All tools returns to that index from any explanation. Read the manual chapter opens the relevant chapter in the bundled manual. Close the explanation to resume photographic shortcuts. The guide is available offline. Icons identify the tools in the index and their explanations. Choose Detach to keep the guide in a separate, resizable window beside the photograph; Attach returns it to the originating help button when that control is still visible in help mode. Otherwise, the next help-button click opens it as a popover. Search, the current article and browsing history survive this change. Help › Develop Field Guide opens it independently of Develop or a selected photograph; Window also lists the guide.

Click a star to favourite an article, and use Favourites to filter the index. Favourites are remembered across launches. Back and Forward return to previous articles and restore their search and favourite filter. Typing a search does not create a history step for every letter. A new destination after Back starts a new branch. All tools clears the filters and returns to the index.

Start with an intention. Decide what matters in the photograph: a face, the quality of light, surface texture, or the relationship between subjects. Crop and straighten to establish the frame, then set white balance and overall brightness. Refine tonal separation, colour and local adjustments before judging sharpening, noise reduction and finishing effects. This is a useful working order, not a requirement to move every slider.

Exposure and tone. Exposure works in stops: +1 doubles linear-light values and −1 halves them before subsequent tone shaping. It changes the rendering, not the number of photons captured. Raising an underexposed shadow makes both its signal and its noise more visible. No adjustment can reliably reconstruct the original texture and colour where the relevant sensor channels all clipped.

Set Exposure for the important subject. Highlights and Shadows shape broad bright and dark regions; Whites and Blacks establish the endpoints. Contrast increases or reduces separation around a fixed pivot. Frames’ pivot is 50% linear light, not the 18% reflectance of a photographic grey card. The tone curve then provides finer control. A steep section increases separation; a flat section compresses it. Lifting the black endpoint gives a matte rendering, while crushing dark values together can hide texture.

Colour has several dimensions. Hue describes the colour direction; saturation describes intensity relative to neutral; lightness describes how light or dark it appears. They interact in a rendered image. Begin with white balance if the light is giving neutrals an unwanted cast. Temperature corrects along an approximate illuminant axis, and Tint corrects across green–magenta. On RAW files, a higher kelvin setting assumes bluer illumination and compensates with a warmer rendering. Rendered JPEG and HEIC files instead receive relative warmth and tint changes.

Vibrance changes colour intensity selectively; Saturation makes a more general change. Neither is an object selection. The Colour mixer adjusts matching colour bands wherever they occur; use a layer when a similarly coloured object should stay unchanged. RGB channel curves can change hue as well as brightness: red opposes cyan, green opposes magenta, and blue opposes yellow. Strong colour changes may exceed an output gamut, so inspect the intended delivery as well as the working preview.

Detail is a tradeoff. At 100%, compare fine hair or fabric with a smooth shadow. Luminance noise reduction suppresses brightness speckle; Colour NR suppresses coloured speckles. Both estimate a cleaner signal and can sacrifice small real features. Sharpness increases edge contrast rather than creating new optical resolution. Detail is a decoder-specific treatment, not a universal radius or a measure of recovered information. Moiré reduction suppresses false patterns caused by sampling repetitive fine structure; it cannot uniquely recover what the sensor failed to sample.

RAW Highlight recovery works in the decoder and may use surviving channel information. The downstream Highlights slider reshapes already decoded tones; it is a different operation. RAW Local tone map controls the decoder’s shadow boosting, separately from Frames’ Shadows and Clarity. Only controls supported by the file and selected decoder are shown. RAW balance and Detail are global; they establish the decoded base before masked adjustments.

Practise by comparing. Move one slider far enough to recognise its effect, then bring it back to a useful amount. Use the group bypass to compare and Undo to reverse an experiment. Use versions for different interpretations. Inspect both the whole composition and a 100% detail view; evaluate grain and sharpening again at the final output size. A stronger adjustment is not inherently a more accurate or more expressive photograph.

The field guide’s application-specific explanations follow Frames’ processing. For background, see Apple’s RAW local tone mapping documentation and the ICC’s discussion of white balance and colour rendering.

See White balance, The tone curve, How a RAW file becomes a picture, What a mask is.