[cybmole]

it seems that whenever I do an epub to epub conversion ( e.g. in order to regularise margins, styles..), any drop caps look very different before and after the conversion.

e.g. a retail epub has a dropcap that extends thru 1st 3 lines of each chapter.
style:
span.dropcaps3line
{
font-size: 4.6em;
float: left;
line-height: 0.75em;
margin-top: 0.0em;
margin-bottom: 0.0em;
margin-left: 0.0em;
margin-right: 0.05em;
}
after calibre conversion - the drop cap is raised & smaller - it extends above 1st line & does not reach 3rd line

the style is now
.dropcaps3line {
float: left;
font-size: 2em;
line-height: 0.75em;
margin-bottom: 0;
margin-left: 0;
margin-right: 0.05em;
margin-top: 0
}

why has calibre halved the font size ?

as I said at start, this is not an isolated case, but this is the 1st time I have actuully examined both before and after styles.
also, I can't see anything in the above to explain why the drop cap now appears higher than it did before

a typical 1st line of chapter is
<p class="nonindent"><span class="dropcaps3line">T</span>he

all that is different in style nonindent is that I have an extra css line that changes margin bottom from 0 to 0.1em during conversion. I can't see that affecting position of dropcap.