color appears different in textcolor versus cell background

In a table that has colored cells, I'm now asked to make some text on white background with the same colors that were used in the colored cells. However, in the mre below, it appears to me that the text color is much lighter than the background of the cell.

\documentclass[letterpaper,landscape,american,11pt]{article}
\usepackage[scaled=0.8]{helvet}
\renewcommand{\familydefault}{\sfdefault}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{array}
\makeatletter

\providecommand{\tabularnewline}{\\}
\makeatother
\usepackage[left=1in,right=1in]{geometry}
\usepackage{xcolor}
\usepackage{colortbl}

\definecolor{gray1}{HTML}{dcdcdc}
\definecolor{blue1}{rgb}{0.2617188, 0.6328125, 0.7890625}

\begin{document}

A little puzzle: the blue cell background looks considerably
darker than the blue letters, which are the same color.

We are pretty sure they are the same color because in row 3,
column 2, the cellcolor and textcolor are set to the same value.

\begin{tabular}{|c|c|c|}
\tabularnewline
Default Cells & are white & w/black FG\tabularnewline
\cellcolor{white}White BG Black FG&
\cellcolor{blue1}{Blue BG Black FG}&
\cellcolor{white}\textcolor{blue1}{White BG with Blue FG: VERY FAINT!}\tabularnewline
Blue FG on Blue BG in neighbor cell: &
\cellcolor{blue1}\textcolor{blue1}{Blue } &
\cellcolor{white}\cellcolor{white}\textcolor{blue1}{{\textbf{Blue bold}}}
\tabularnewline
\end{tabular}

\end{document}


Please look at row 2 column 3 for the text that appears pale to me, in comparison to the vivid blue in the neighboring background. Row 3 column 2 is blue text on blue background, where the it appears the colors of text and background are same.

I thought there must be some error caused by \color and \textcolor, but I don't think so. The colors are same, but they appear differently when drawn on "Narrow" letters surrounded by white. When I write colored text on same-colored background the difference seems to disappear.

I have fiddled with the colors and it appears I need to dial down the RGB combinations for color intended for text quite a bit if it is going to appear similar to cell background color. Seems odd.

Here is the question: Is this a "known problem" in manuscript preparation that has a known fix? Given an RGB value for a background shade, is there a systematic transformation that makes text appear similar in color to many people?

• What's the question? You can see from the blue-on-blue the colours are the same. So, what exactly do you want to know? If it is about why they look different, the question is off-topic for this site. If it is why LaTeX uses the same colour, it is because you told it to. If it is why LaTeX doesn't use a different colour, it is because you didn't ask. – cfr Jan 28 '17 at 2:04
• I've added a more clearly stated question. – pauljohn32 Jan 28 '17 at 3:25
• This might be better asked on the graphics design SE. But I don't think there could be a general solution because it will depend on the font. – cfr Jan 28 '17 at 3:51