Batch Action Changes 8 bit Images to 16 bit

[Outtacontext]

I created an action to prepare an image for printing. It includes a step to flatten the image. My Photoshop file starts as an 8 bit image. If I manually run the action the result is also 8 bit. 

However, if I batch run the action in Photoshop (File >Automate) all the images end up as 16 bit!!

What's happening?? And how do I get Photoshop to stop converting 8 bit to 16 bit? I've also noticed that when I open an 8 bit file, Photoshop converts it to 16 bit. 

One more question: is changing the bit depth lossless? I know the color differences between 8 bit and 16 bit images. But if Photoshop is going from the original 8 bit to 16 bit, and then I convert it back to 8 bit, will the image quality degrade from the original 8 bit image?

Thanks. 

[PECourtejoie]

Hi, can you check if you did forget configuring an 8>16 action in the Scripts Events Manager.. of the File>Automate menu?

The 16>8 bit jump usually adds a bit of dithering, in order to smooth gradients created in 16bits, to avoid stairstepping.

[Outtacontext]

Can you post a screenshot of where that is?

[Bojan Živković]

[Outtacontext]

Here's the dialogue box for Batch Action in my Photoshop. I don't see what you're referring to.

[Outtacontext]

I just noticed that it's also changing an 8 bit PSD to a 16 bit TIFF if I just manually run the action!!

I've been having problems lately with 8 bit images opening as 16 bit and I don't know why.

[Outtacontext]

Even if I don't use an action and do the file manually, flattening the 8 bit PSD, enlarging the canvas to give it a white border and then saving it as a TIFF, after I do that, and without closing the file, it shows it's an 8 bit TIFF. But when I close and reopen it, it's suddenly a 16 bit TIFF! As I said, this has been happening for the last couple weeks. I changed my MacOS from Big Sur to Monterey, but that's the only change I've made. I noticed it with Photoshop 2022 and Photoshop 2023.

I think it's saving it as an 8 bit, but when I open the TIFF it's opening in Camera Raw and that is converting it to 16 bit.

IS THERE ANY WAY TO OPEN A TIFF DIRECTLY WITHOUT OPENING IT THROUGH CAMERA RAW?

[D Fosse]

[PECourtejoie]

Ah, yes, @Outtacontext your username is relevant to the thread: Do you see the camera Raw dialog when you reopen the tiff?

At the bottom, click the hyperlink to change to 8bits.

[Bojan Živković · Accepted solution]

Here is visual what should be done because this step can not be skipped when opening .raw files.

[Outtacontext]

Thank you, Bojan!

[Test Screen Name]

When you open in Camera Raw things beconme 16 bit. So don't open in Camera raw. Open the normal way (with Open from the File menu).

[Outtacontext · Accepted solution]

Okay, this problem has been solved. Apparently, opening my 8 bit tiff files automatically into Camera Raw when I open them in Photoshop was converting them to 16 bit. I had a great Adobe rep who showed me how to turn off the preference that makes a tiff open in Camera Raw. And it's all working fine now.

[D Fosse]

I had a great Adobe rep who showed me how to turn off the preference that makes a tiff open in Camera Raw.

By @Outtacontext

You didn't need an Adobe rep for that, I showed you how in a screenshot above.

[Outtacontext]

Yes, thanks. At the time, I was under a big deadline and I didn't understand the image you provided. So, I need help right away. As it turns out, the images were 8 bit. Only when I opened them to check did they become 16 bit.

Anyway, I do appreciate all the help all of you provided.

[Johan32304666waz7]

The problem is not actually solved - the tiff files are still corrupt if you (or a client) wants to open them in another photoshop. I´ve been having problems with this issue many years now... Please solve this one, Adobe!