Colour space gets confusing because two questions share one word: what you work in, and what you deliver. They have different answers.
Edit in a wide colour space and deliver sRGB. Work in Adobe RGB or ProPhoto at 16 bits to keep your options open, convert to sRGB for anything that will be seen on a screen, and ask the lab or designer what they want for print. Most colour problems come from giving the editing answer to the delivery question, or the reverse.
What do I edit in? and what do I deliver? sound like one question, and treating them as one is where most colour problems start.
What a colour space is
A colour space defines which real colours the numbers in a file stand for. The same RGB values describe a different colour in sRGB than in Adobe RGB.
Some spaces cover a wider range of colours than others. Wider is not automatically better: the same number of steps is spread across more colours, so each step is larger. In an 8-bit file that shows up as banding, which is why bit depth and colour space have to be decided together.
The three you will meet
sRGB is the smallest of the three and the default almost everywhere. Browsers, phones, social platforms and most consumer print services assume it, and a file with no embedded profile is usually treated as sRGB.
Adobe RGB is wider, especially in greens and cyans, and covers more of what a printing press can reproduce. That is why many print workflows use it.
ProPhoto RGB is wider still, wide enough to include colours no screen or printer can show. It only makes sense at 16 bits, where the extra precision prevents banding.
The rules
Edit in a wide space
Work in Adobe RGB or ProPhoto at 16 bits. That keeps your options open: colour you discard cannot be brought back, and every adjustment does less damage when there is headroom.
Deliver for the destination
Web, social, email, anything seen on a screen: sRGB.
Upload an Adobe RGB file to a platform and the numbers get read as sRGB, which makes the image look flat and dull. It is one of the most common colour mistakes, and one setting on export avoids it. Export settings for Instagram covers the rest of a social export.
Prints from a lab: ask the lab. Some want sRGB, some want Adobe RGB, and some supply their own ICC profile. Their answer is the one to follow.
A client working with a designer: ask the designer. They may want Adobe RGB, a specific CMYK conversion or the layered original.
Your archive: keep the master in your working space at 16 bits. Delivery files can be regenerated from it. The master cannot be regenerated from them.
Convert, do not assign
These are different operations, and one of them changes colours in a way people do not expect.
Convert recalculates the numbers so the colours look the same in the new space. On export, this is what you want.
Assign changes the label and leaves the numbers alone, so the colours shift. It is occasionally the right fix for a file tagged with the wrong profile. It is almost never right on export.
Embed the profile
Always. Without one, every application has to guess, and most guess sRGB.
Two problems worth recognising
"My photos look flat online." Nearly always an Adobe RGB or ProPhoto file uploaded without conversion. Convert to sRGB on export.
"The print does not match my screen." Usually the monitor rather than the colour space. A hardware-calibrated display is the dependable fix, and soft proofing — previewing with the printer's profile applied — shows which saturated blues and greens will not survive before you pay for paper.
Telling us where the file is going
A file prepared for a screen and a file prepared for paper are different files. When you send work for High-End Photo Retouching, say in the brief where each frame will be used and which profile the lab or designer has asked for. The Editorial / Campaign package lists delivery for web or print, and the brief is where that choice gets made.
Label what you deliver
When a client receives files for more than one destination, the colour space should be obvious from the folder, not something they have to find in a metadata panel.
Name the folders for their purpose, such as "web-sRGB" and "print-AdobeRGB", and never mix the two in one folder. If a designer is involved, add a one-line note saying which profile is embedded and that the files have been converted, not assigned.
It takes a minute. It prevents the most common complaint about delivered files: an Adobe RGB print file posted online that looks flat, followed by an email asking what went wrong with the edit.
Common questions
What colour space should I edit in? Adobe RGB or ProPhoto at 16 bits. Colour you discard cannot be recovered, and adjustments do less damage when there is headroom.
What should I deliver for web use? sRGB, converted on export with the profile embedded. Browsers, phones and social platforms assume it.
What should I send a print lab? Whatever the lab asks for. Some want sRGB, some want Adobe RGB, and some supply their own profile; follow their answer rather than a general rule.
What is the difference between converting and assigning? Converting recalculates the numbers so the colours stay the same. Assigning changes the label without touching the numbers, so the colours shift. On export you almost always want to convert.
Should I use ProPhoto RGB? Only at 16 bits, and only if you have a reason. It includes colours no screen or printer can show, and at 8 bits that width causes banding.
Related reading: RAW vs JPEG for Professional Retouching and How to Fix Mixed Lighting and Wrong Skin Tones.
BeEdits Editorial Team
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A photography post-production company: high-end retouching, creative editing and scalable production support for photographers, studios and brands.