For photographers who export for galleries, phones and print labs. Checked against CullTone on 20 Oct 2026.
A colour space is the range of colours a file is allowed to describe, and the meaning of its numbers. The same red pixel, value 255, is a different red in sRGB and in Adobe RGB. Send a file in one space to a screen that assumes another and the colours shift, usually toward flat and dull.
The horseshoe is every colour of light people can see, plotted on the CIE 1931 chart. Each triangle joins the red, green and blue of one colour space; a file in that space can only describe colours inside its triangle. The fill is a rough guide to the hues, not an accurate picture of them, since no screen can show the whole horseshoe.
| Space | Where it comes from | What it's for |
|---|---|---|
| sRGB | HP and Microsoft, 1996 | The web, phones, most screens, most consumer print labs. The default whenever a file has no profile. |
| Display P3 | Apple, from the cinema P3 primaries | Recent iPhones, iPads and Macs, and many newer phones. Richer reds and greens on screens that can show them. |
| Adobe RGB (1998) | Adobe, 1998 | Print. Reaches further into cyan and green, which some printers can reproduce. |
| ProPhoto RGB | Kodak | Editing headroom. So large that part of it lies outside the colours people can see. |
Here is our position for client galleries: deliver sRGB, even to couples with the latest phones. A file in sRGB looks right everywhere, including the places nobody checks: an old laptop, a smart TV slideshow, a messaging app that strips the profile out of every photo it forwards. A file in Adobe RGB or Display P3 looks richer on a screen that reads its profile and duller on one that doesn't, and you have no control over which screen the family uses.
Wide-gamut screens do show more, and for some work, such as saturated stage lighting, a P3 file genuinely looks better on a phone that supports it. We just don't think that gain is worth one aunt seeing a grey, flat version of the bride's sari on a cheap tablet.
CullTone's finished JPEGs are sRGB. If you want a wider space for a particular job, finish those frames in your own editor from the XMP sidecars (Lightroom handoff).
Many consumer labs expect sRGB and convert everything else, sometimes badly. Some professional labs accept Adobe RGB and get a little more cyan and green out of it. The only reliable answer comes from the lab itself, so ask which space they want and whether they publish a printer profile you can soft-proof with. That one email costs you two minutes; a reprint of an album costs far more.
A sensible pipeline works in a large space while editing, so nothing gets clipped halfway, and converts once at the end to the space the output needs. Converting from a large space to sRGB squeezes colours that don't fit, and the deepest saturated reds and greens of a stage show or a garden can lose some separation there. That is a fair trade for a file that looks the same on every screen. For the other half of file quality, read bit depth: RAW against JPEG.
Full-size sRGB JPEGs at quality 95, in a client gallery that opens in any browser.