Overview of the preferred graphical formats

Type of graphics Bitmap or vector? Minimum resolution Colour model Format

Graph, map etc. Vector* 300 dpi RGB or black and white CDR (<=2018), EPS, AI (<=CS4)
(± just for preview PDF, bitmap)

Line (scanned) Bitmap 1200 dpi 256 greys TIFF (+LZW compression)

Grayscale (e.g. BSE images from microprobe) Bitmap 600 dpi 256 greys TIFF (+LZW compression)

Photo (black and white) Bitmap 300 dpi RGB or 16-bit greyscale (NOT ordinary greyscale, as it is restricted to 256 shades of grey only) TIFF (+LZW compression), JPG (low compression ratio)

Photo (colour) Bitmap 300 dpi RGB TIFF (+LZW compression), JPG (low compression ratio)

* Vector graphics is much easier to edit, results in best printing quality and the smallest files (including the final PDF of the whole article). As such it is strongly preferred to bitmap formats. Even for plates of photographs, the best results are achieved by combination of bitmap photographs with vector text annotations.
For more information, see Wikipedia: Vector graphics and Raster graphics.

Type of graphics	Bitmap or vector?	Minimum resolution	Colour model	Format
Graph, map etc.	Vector*	300 dpi	RGB or black and white	CDR (<=2018), EPS, AI (<=CS4) (± just for preview PDF, bitmap)
Line (scanned)	Bitmap	1200 dpi	256 greys	TIFF (+LZW compression)
Grayscale (e.g. BSE images from microprobe)	Bitmap	600 dpi	256 greys	TIFF (+LZW compression)
Photo (black and white)	Bitmap	300 dpi	RGB or 16-bit greyscale (NOT ordinary greyscale, as it is restricted to 256 shades of grey only)	TIFF (+LZW compression), JPG (low compression ratio)
Photo (colour)	Bitmap	300 dpi	RGB	TIFF (+LZW compression), JPG (low compression ratio)