I'm creating a simple color layer with several layers of text and the text, while looking good on iphone, on my MacBook Pro it seems to come out fuzzy.
The base file is tiff and I'm exporting as png, 1080x1080 pixels with 600dpi, sometimes 1000dpi.
Should the base file be .psd?
Should I export as pdf, then come back for png or jpg (the 2 formats Instagram allows)?
Should I lower the dpi and/or increase the size, or what?
Attached is a file that would show the fuzzy edges around text when viewed on my monitor. Tho it looks fine here, it don't on Instagram or, especially badly, on Facebook.
DPI is irrelevant on the web. It's all absolute pixels. The rest could be anything from color management issues to files getting dynamically compressed by your service provider to save bandwidth. Also, a text treatment with mostly solid color areas will always look bad on some devices, be it for inherent limitations of how e.g. JPEG compression works or the files getting resampled for display purposes. A lot of that is beyond your control, so just accept it.