Correct settings for exporting grayscale heightmap from Photoshop?

[Kekswalker]

Might be a stupid question, but I've been following the guide on map modding on the wiki and also one here on the forum but still could not figure out how to correctly export my heightmap from Photoshop so the map editor accepts it. When trying to load as a standalone heightmap onto the existing world map in the editor, it just gives me errors;
The original heightmap is using 2 bpp, 1 channel, mine hower is 2bpp, 3 channels, whatever that means. I'm not experienced in any of this and basically tried this as a hobby.

What could be the problem?

 

[Stauffenberg13]

8 bit grayscale image works for me.

 

[Kekswalker]

8 bit grayscale image works for me.

Doesn't seem for me, not sure what I'm doing wrong
This is the error message I always get, no matter what I try:

 

[Dingus17]

3 channels suggests its RGB, might be wrong. Make sure your not just using grays but that the image is actually in the grayscale format.

 

[Kekswalker]

3 channels suggests its RGB, might be wrong. Make sure your not just using grays but that the image is actually in the grayscale format.

Ok, so I went back and tried some stuff, until it finally worked. In case anyone else in the future has the same issue and doesn't know what they're doing as well, here's what I did:

The image mode itself in Photoshop is definitely set to grayscale, the only problem is when exporting it to png Photoshop just applies some crap to it I don't actually want for the image.
This happens when using "Quick Export as PNG", "Export as...", and in most cases of "Save for Web (Legacy)", however I found a setting that finally worked for me. Smarter people might have immediately known where to look and what to use, my method of choice was trial and error.

The settings I ended up using that worked were the following: