From ecbbb3686c5d0ceb1176b4c97cd684c7defeca1a Mon Sep 17 00:00:00 2001
From: Koen Hufkens <koen.hufkens@gmail.com>
Date: Fri, 19 Jan 2024 20:49:13 +0100
Subject: [PATCH] docs

---
 vignettes/foto-background.Rmd | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/vignettes/foto-background.Rmd b/vignettes/foto-background.Rmd
index f65dcc1..4297bbd 100644
--- a/vignettes/foto-background.Rmd
+++ b/vignettes/foto-background.Rmd
@@ -178,4 +178,6 @@ p  <- ggplot(df) +
 
 print(p)
 
-```
\ No newline at end of file
+```
+
+Note that decreasing the number of pixels in the analysis will reduce the spectra size. With fewer features used in the PCA to discriminate different textures results will be less nuanced. Also note that the `foto` package discards the low order features (applies a low pass filter) to remove the underlying image mean. This can be turned of if desired.