diff --git a/reader.cpp b/reader.cpp
index 86c9a66..bcfbf47 100644
--- a/reader.cpp
+++ b/reader.cpp
@@ -1034,7 +1034,7 @@ void reader::on_nextBtn_clicked()
         }
         else {
             mupdf::pdf::pdfPageNumber = mupdf::pdf::pdfPageNumber + 1;
-            if(ui->pdfScaleSlider->value() != 0) {
+            if(ui->pdfScaleSlider->value() != 1) {
                 mupdf::convertRelativeValues = true;
             }
             setup_book(book_file, mupdf::pdf::pdfPageNumber, true);
@@ -1075,6 +1075,9 @@ void reader::on_previousBtn_clicked()
         }
         else {
             mupdf::pdf::pdfPageNumber = mupdf::pdf::pdfPageNumber - 1;
+            if(ui->pdfScaleSlider->value() != 1) {
+                mupdf::convertRelativeValues = true;
+            }
             setup_book(book_file, mupdf::pdf::pdfPageNumber, true);
             setupPng();