Preview background removal turns black on website upload

First, make sure that the file is png and not jpeg; jpeg files do not support transparency at all.

Preview should have asked you if you want to convert to png, so that is probably ok, but still worth asking, to be sure.

Second, where are you seeing the image?

To correctly ascertain if the background is or is not transparent you will need to see the image composed on top of something. Perhaps in the context where you are seeing it the image is rendered against a black background?

dmichael.wagner wrote:

This was a photo taken with my iPhone, Airdrop onto Mac, open in Preview, click the remove background icon, convert to png, save, import into Photo or any website and it comes out with a black background.

I've confirmed the general Preview setting is white

Perhaps you need to go into more detail. I just tried all of that, and this was the result:

I took a photo on my iPhone 11 Pro. Then I airdropped that to my Mac. It showed up as an HEIC file. I opened that with Preview and removed the background. That worked as expected. Then I chose "Export" from the "File" menu. I selected "PNG". I made sure "Alpha" was checked. I clicked "Save" and it worked as I expected.

I didn't upload the file to any websites other than this one. It imports into Photos exactly as it looks here. Are you doing something differently?

Curiously, when I initially did the export, it defaulted to "JPEG". I did use that earlier. I looked at that again and when I selected "JPEG", it still had an "Alpha" setting, but it was disabled, and checked. JPEG, like many other formats, has many varieties. Perhaps Tahoe now supports some new JPEG-XL or something that has transparency support. I don't know. But when I exported to JPEG, I did get a black background, almost as you describe.

https://discussions.apple.com/content/attachment/28fc724c-5c2a-47d0-b08a-1f56d969cf77

But I have to say "almost as you describe", because your image actually has two backgrounds. There is a black border around the red object. But then there is a white border around that. So clearly, something else is going on with your image that you haven't yet described.

dmichael.wagner wrote:

I confirmed the setting in "Preview" was set to white. I looked for transparent and or translucent and this is not an option.

It sounds like you're talking about Preview's window background colour. Obviously transparency can't be an option for this because it's designed to show transparency in the image itself. This has nothing to do with the background removal feature.

What kind of image did you start with? Preview is designed to work with images taken with your iPhone camera. There's no guarantee that anything else is going to work. I can't even get the "Remove background" option to be enabled unless I started with an iPhone image.

The most likely explanation here is that you have an image that is close enough to a recognizable "photo" for Preview to attempt to remove the background. But something about that particular image causes the background to be black instead of transparent when uploaded to websites. For example, I can easily see this happening with a GIF image. Maybe 20 years ago, this kind of thing was a regular occurrence.

The remove background feature definitely works. It just doesn't work with whatever image you started with. While GIF is an extreme example, there are many other types of images and image options that could generate the same end results.

There are a couple of ways of replacing the background with transparency in a PNG, and Preview is one:

• https://osxdaily.com/2023/01/19/how-to-remove-the-background-from-images-on-mac-with-a-quick-action/
• https://osxdaily.com/2013/01/27/make-a-transparent-image-png-or-gif-easily-with-preview-for-mac-os-x/

Affinity Photo seems to have transparency options here, too:

• https://nextdesignr.com/affinity-photo-transparent-background-tutorial/
• https://affinityrevolution.com/how-to-remove-white-backgrounds-in-affinity-photo/

Which website, what upload, and who is managing the website and whatever code the webserver might be running?

dmichael.wagner wrote:

why does my background turn black when uploading to a website after I remove the back ground in preview

I have no idea what it is your are trying to describe here..are you asking about transparent background?

Not all file types or websites are going to play nice. Do something different if this is an issue.

specific website all websites ?

file type?

Screenshots?

the most used interface for screenshots —

Shift Command 3

Shift Command 4

Take a screenshot on Mac - Apple Support

I would eliminate any background, don't use the newer "Shift Command 5" if it provides an issue.

Set default options here and compare your results:

Shift Command 5 make changes to suit your needs

Take screenshots or screen recordings on Mac - Apple Support

screenshot default is .png it supports transparency ..

You can change this from the Terminal.app copy and paste:

defaults write com.apple.screencapture type png && killall SystemUIServer

Preview.app itself has Settings for viewing on your screen...

FWIW I was able to remove the black background using Preview.