Certain TIFF files don't display properly, looks correct in Photoshop/Irfanview

[immewnity]

I've come across a handful of TIFF files, created in an old version of Photoshop (Photoshop 7.0), that don't open properly in Affinity Photo. I don't really know how to explain it, so I've attached a comparison below, along with a sample file. This shows in the current version of Affinity Photo (1.9.1) and the previous build (1.9.0), have not tested in earlier versions.

Sample file: EX_Team_Rocket_Returns_Mewtwo_Booster.TIF

Comparison:

[Gnobelix]

Hello @immewnity,

 

open the TIF files in Photoshop and delete the alpha channel 1,
then the TIF files should open properly in Affinity Photo.
According to my knowledge, can Photoshop save alpha channels in TIFF files and  Affinity-Photo not.

 

Cheers

 

EX_Team_Rocket_Returns_Mewtwo_Booster-2.tif

[Chris B]

Hi—sorry what am I missing? The file opens up and look right to me in Affinity Photo without removing the Alpha channel. The only difference is that glow down the left-edge:

I'm certainly not seeing what you showed in your comparison screenshot 😮 

[Komatös]

For a proper comparison, a screenshot of both Photoshop and Affinity Photo would be helpful.

For a quick screenshot (Windows 10), press the Windows key and the Print key. The screenshots should be found in the Pictures 

[Joachim_L]

34 minutes ago, Chris B said:

The file opens up and look right to me in Affinity Photo without removing the Alpha channel.

Which version did you open? The repaired one from Gnobelix or from the OP? Even with the same beta the original image opened wrong.

[Komatös]

@Chris B Open the file from the first posting. Then go to the channels and invert the background alpha channel.

[2:3]

8 hours ago, Komatös said:

@Chris B Open the file from the first posting. Then go to the channels and invert the background alpha channel.

... that works, thanks.

But it only shows either background and foreground. What if there is information on both channels? How do I show / combine both? 

[Chris B]

😳 I was sure I opened the file from immewnity... Inverting does work but ideally we'd like to open the file and have it just work. I will pass this back to the developers.

[2:3]

34 minutes ago, Chris B said:

😳 I was sure I opened the file from immewnity... Inverting does work but ideally we'd like to open the file and have it just work. I will pass this back to the developers.

I remember I had that same issue with placing Tifs wit an alpha channel in Publisher some time ago. I was hoping that was solved, therefore I searched for that again.:

In fact it does not work properly at all – there is a bright halo left around the selected shape.

Last year I was told that: "The bright halos are because RGB values have been brightened by the broken TIFF importer. The TIFF importer seems to assume that the file's RGB values have been premultiplied with black where alpha is not zero, and so it un-premultiplies where alpha is not zero, hence the bright halos when alpha is filled. (Someone at Serif should have debugged this years ago!)"

see my topic here: 

 

I don't know if that has been passed to the developers?

Because I have 1000s of tifs from 25 years with all kind of channels here, that I cannot open in AP, I would be very interested in a solution.