Can you provide the file for testing?
Or provide a screenshot displaying more information for each of the two Type Layers.
What happens of you copy the texts from both Type Layers and paste them into newly created Type Layers?
I marked this thread to follow hoping to see an answer, as it's interesting. It went a day before getting any response, so please keep bumping it till you get a meaningful answer.
I have since deleted offending layers, but I did try a number of solutions prior to starting anew. If text was copied from the heavier layer and pasted into the lighter layer, the result was lighter. However, if I simply copied the entire layer, it would remain heavy. I tried resetting every option I could think of, including using system layout, turning off anti-aliasing, removing all formatting and restarting, but the differences remained.
I still see inconsistent results when switching the anti-aliasing options, but I haven't been able to replicate the variance in two identical layers. I'm wondering whether this was caused by the fact that I use a retina display (2x pixel density) Macbook Pro with a 1x pixel density external Apple Thunderbolt display. The image was originally created while using the external display, and the discrepancy arose when I was disconnected from the external monitor and only using my Macbook Pro. Dragging a window between the two displays automatically changes the zoom level from 100% to 200%, and I'm sure other factors can get affected.
For now, I'm simply using whichever anti-aliasing option looks most legible for a particular typeface, knowing that I'll likely have to make changes to text weights when I code. It's not an ideal solution because I'm designing something that will look different in a browser, but unfortunately the text rendering in Photoshop is still unable to match that of browsers (especially for high-density displays, but that's a different issue altogether, and one I hope is addressed in future updates).
If anyone has experienced similar issues before and has any insight, I'd love to hear it.
I'm wondering whether this was caused by the fact that I use a retina display (2x pixel density) Macbook Pro with a 1x pixel density external Apple Thunderbolt display.
I suppose that might produce an issue when viewing the document in Photoshop. Did you try saving out and comparing the JPG (or whatever format you use) image?. It is very rare for us to see a totally unique issue on this forum, and rarer still to find no similar issues with Google, but your post was new to me.
I have the exact same problem. However, i just use an iMac. No external screens. I truly believe this must be a PS bug.
See my post in the forums, here: Re: Photoshop Font Rendering Changes While Working (Problem)
Check the video too, and see how those particular actions there affect the font. But if i transform the text layers directly, not the folders with other re-renderable elements, the font anti-aliasing is preserved.
Out of curiosity, do the font changes its size+line-height randomly too? Like, from 16pt to, say, 16.09pt?
I still don't have a good solution to it. I just avoid transforming text layers with other objects.
Did you ever find a solution to this? I'm encountering something similar where a font layer from an older file appears much different than a font layer in a new file.
Everything about the following text layer are identical. Same font, color, rendering style. There's no "faux bold" applied or anything else. The only difference is the one on the left was created in a file about 2 months ago and the one on the right is from a new file.
Anything new I type appears like the one on the right. However, I have a bunch of files for this client dating back a few months that have fonts rendering like the one on the left. So frustrating.