Fits 72 dpi

@nordiclightphoto DPI is a measure for how many dots per inch will be used when printing an image. It has no effect on the actual file that is produced when saved. If you intend to print the images then you can convert them to TIFF and modify the DPI value with an external tool. 

So Wouter, does that mean that I can leave it at 72 DPI in APP and not lose any data, then increase it before I save a final version if I will print it? I tested at both 72 & 300 DPI and saw that the file size seems identical. Or even leave it at 72 DPI and increase it in e.g. PS, if I am going to do some final touchups there?

@mfc Mark, yes that is correct.

Thanks. And I forgot to add that my first impression of the new features is fantastic - I just have to learn how to use them. I can already see that much more of my processing both should and is going to be done in APP than I have been! A great release...

@wvreeven Thanks Wouter.  So what you are saying is that when I use a FITS file in PS / Affinity Photo (it can read FITS files) the resolution is not comprised?  Or do I need to bump up the DPI in APP when exporting it as a tiff?  I have seen that by the export you can increase the DPI.

In other words FITS is resolution independent?   

@nordiclightphoto As a matter of fact, ALL image dimensions are DPI independent. DPI only defines how the image will be printed. Not how many pixels there are in the image. A higher DPI only means that the printed image will be smaller on paper. If the DPI is too low then you'll see the individual pixels on paper.

When processing astronomical images, the only thing that matters is the spatial resolution of the telescope/camera combination, how well guiding has been performed, seeing etc. But a camera always produces the same number of pixels and that number only changes if the camera is binned or if the image is scaled. DPI is completely independent of this.

@wvreeven Thanks Wouter.  Will keep this in mind