ID 14.0.2 sometimes switches to CMYK Proof (Proofing OFF). Why?

[craftycurate]

Hi

I am creating an InDesign document which uses an RGB palette created with Adobe Color and imported into the current document via my Library. All colours display correctly on screen until:

- I overlay a coloured shape (using an RGB swatch) using Multiply blend mode

- Place a transparent PNG (but NOT an opaque PNG)

The behaviour does not happen if I

- Place an opaque PNG or a JPG, or PSD

When I do either of these, the screen view switches to CMYK proof colours (much duller), even though View | Overprint Preview and View | Proof Colours are OFF.

Once the colours have been dulled in this way, and I export to interactive PDF, the colours show up correctly in the PDF, so this is just a display issue in Indesign.

if I delete the placed transparent PNG or switch the coloured shape's Blend Mode back to "Normal", the problem disappears and colours are displayed correctly, as RGB.

The project deliverable is a digital only PDF so I am working entirely in RGB, and have no need or desire for print proofing, so this behaviour is obstructing my workflow, as I don't want to have to guess what the output will be. I need the screen colours to match the interactive PDF output.

If anyone would please suggest what is happening here and how can I fix this buggy\weird behaviour. It might be my lack of knowledge, and if so, I hope to learn what is happening, but I've worked on similar projects in the past with similar InDesign features used and have never seen this before.

Any help appreciated!

Thanks
Richard

[Test Screen Name · Accepted solution]

Check your transparency blend space for the document. What you describe so clearly is exactly what will happen if it is set to CMYK.

[craftycurate]

Thanks for getting back. That's fixed it! It would make sense as both actions that cause the effect involve transparency.

Cheers

Richard