## How to get the best results printing white text with small font-size on a rich black background

I need to produce a document that has a flat rich-black (C60, M50, Y40, K100) background and text that is white on top. The text is set at 7pt in a monospaced font (PT Mono Regular 400).

## Compute White Underprint Values

I want to print this motif on a grey hoodie using DTG, how would I compute the color values for the white underprint to make the colors on grey fabric approximate the colors in the image? My intuition is, after converting to CMYK (assuming no pixel has positive values in all four channels), I subtract the K value of the background grey from the K value of each pixels, the negative K values give me exactly the intensity of the white underprint needed to represent the color. Is that somewhat correct?

[EDIT] My back of an envelope calculation went like following. Assume for simplicity that every layer tranlucent print of color S ∈ {C, M, Y, K} lets light of color A ∈ {R, G, B} pass at rate S(A). Assume further that the fabric reflects light of color A at rate F(A), and a layer of white print on the fabric with opacity w reflects light of color A at rate w + (1 – w) F(A). So a standard CMYK conversion of the RGB image with corresponding values r, g, b would tell us what values c, m, y, k approximate a ~ (c C(A))² (m M(A))² (y Y(A))² (k K(A))² for (a, A) ∈ {(r, R), (g, G), (b, B)}. We want to find values c’, m’, y’, k’, w to approximate a ~ (c’ C(A))² (m’ M(A))² (y’ Y(A))² (k’ K(A))² (w + (1 – w) F(A)) for (a, A) ∈ {(r, R), (g, G), (b, B)}. To have the grey being transparent, we must further assume that approximating a := F(A) gives all zeros.

## How many inches/mm is left as margin on a standard A4 paper?

Is there a standard length of margin left that works for all printers? On my note taking app I want to know how much space to leave so that when I export to PDF and print (on HP, Brother, Epson, you name it) none of the text is left out.

## illustrator printing

It is true there are specific special conditions in which white may
actually be a colour of ink or toner explicitly called for – but this
is an atypical workflow relative to the vast preponderance of prints –
and bluntly – spot colours, separations, Pantone definitions and so on
are the province of the industry of professional graphic designers and
print shops – of which you clearly are not part.

## What is the recommended way to design a standee for print, in terms of dimensions?

I need to design a standee 3×4 feet (36×48 inches at 300 DPI). The main element would be a 10-15 MB photo (4000×5000 pixel dimensions approx.) inside it and a text heading and 1-2 design elements. The problem: When I create a document in either Photoshop or Illustrator for print (36×48 inches, 300 DPI), it … Read more