Transparency in a TIFF file

[fabiano.cudazzo]

Transparency in a TIFF file, both Photo and Design, is not displayed.
Thank you

tumor growth.tif

[Old Bruce]

We need to have an Affinity Document with a Transparent background set up in order to Export a TIFF with transparency. If I open your tutor growth file it shows transparency and if I place it in a Photo Document with a transparent background (check the transparency box in the New dialog) I can then export it as a TIFF with Transparency (using the 16bit PNG preset), If I place your file in a Photo document without transparency then I cannot export it with transparency.

[joe_l]

15 minutes ago, fabiano.cudazzo said:

Transparency in a TIFF file

Confirmed. V1 opens them showing the transparency. Placing this file in V2 gives no problem.

[fabiano.cudazzo]

thank you soo mutch

[lacerto]

Obsolete.

[walt.farrell]

On 12/1/2022 at 12:13 PM, lacerto said:

A TIFF file can have transparency both straight (unassociated alpha) and premultiplied (associated alpha). Affinity apps v1 would open both kinds of transparencies and make the former kinds of images to associated alpha transparencies without an alpha channel, while version 2 apps do not (they still place both kinds of images similarly, "as (normally) expected", applying the transparency)

I am not sure but I suppose this is a deliberate change and can be useful in certain scenarios. The following clip shows how the unassociated alpha can be loaded to image alpha in Photo 2 (and thus "restore" version 1 behavior):

Edit: Another user in that other thread pointed out my mistakes in trying to use your approach:

1. I didn't have the Background layer selected.
2. A right-click is required.

So, I no longer have a question for you, @lacerto.

---

There's a TIFF file in the first post of the topic I've linked to below that seems to have a problem related to an unassociated alpha channel.

But when I try what you showed in your video I don't get the same popup choices you got when I click on that channel. Your video is from 2.0, I think. Has something changed in 2.1, perhaps?  Thanks.