InDesign 2025 transparency and drop shadow issues

Forum|Forum|8 months ago
July 2, 2025
3 replies
287 views

iMac 2017, Ventura 13.7.6, InDesign 2025

Applying a small transparent caption frame over a full page greyscale image causes the whole image to lose contrast when transparency is applied.

Also when applying drop shadow to an item on a spread, greyscale images on that page and adjacent page also lose contrast. These images do not contact the drop shadow item in any way.

I cannot see any change to CMYK images.

Is this a bug - any advice please?

Phil in Welland, UK

Bug

Abhishek Rao

Community Manager

Hi @philipb31687500,

Thanks so much for sharing the details. I see that Eugene suggested checking your transparency blend space (under Edit > Transparency Blend Space), which is often the key reason for contrast changes in grayscale images when using transparency or drop shadows. Could you please try that and let us know if it helps?

Also, could you confirm the exact version of InDesign 2025 you're using, for example 20.4.1 or 20.4?

If possible, it would be really helpful if you could share a short screen recording showing the issue happening on your layout, so we can review it in detail.

Looking forward to your update!

Abhishek

P

philipb31687500Author

Participant

Try again!

Thanks all for the replies.

Blend space is Document CMYK.

The greyscale images originate as scans supplied to me for printing and arrive already as greyscale, or sometimes as RGB. So in Photoshop Image>Mode>Greyscale.

InDesign is 20.4.1.

What I find difficult to understand is how a greyscale image can change when it is nowhere near where the transparency is being applied.

The suggestions made did cause me to make an experiment and change the greyscale to CMYK. And that seems to work. Don’t understand why!

Please see the short screen recording, with the image duplicated - one in CMYK and original in greyscale.

Many thanks again, and suggestions welcomed. Hope the movie works…smaller now.

Phil

rob day

Community Expert

What I find difficult to understand is how a greyscale image can change when it is nowhere near where the transparency is being applied.

Grayscale images display on the CMYK Black place when the Transparency Blend Space is CMYK, and Overprint Preview is turned on, or when there is any transparency on the spread. Most CMYK press profiles display 100% Black as something less than absolute black, which is what will happen on press. A rich black (black plus CMY percentages) will appear as a darker value on press.