diff --git a/lib/redeyereduction/redeyereductionimageoperation.cpp b/lib/redeyereduction/redeyereductionimageoperation.cpp
index 15a79841..8622142b 100644
--- a/lib/redeyereduction/redeyereductionimageoperation.cpp
+++ b/lib/redeyereduction/redeyereductionimageoperation.cpp
@@ -1,118 +1,118 @@
 // vim: set tabstop=4 shiftwidth=4 noexpandtab:
 /*
 Gwenview: an image viewer
 Copyright 2007 Aurélien Gâteau <aurelien.gateau@free.fr>
 
 This program is free software; you can redistribute it and/or
 modify it under the terms of the GNU General Public License
 as published by the Free Software Foundation; either version 2
 of the License, or (at your option) any later version.
 
 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.
 
 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 
 */
 // Self
 #include "redeyereductionimageoperation.h"
 
 // Stdc
 #include <math.h>
 
 // Qt
 #include <QImage>
 #include <QPainter>
 
 // KDE
 #include <kdebug.h>
 #include <klocale.h>
 
 // Local
 #include "document/document.h"
 #include "document/abstractdocumenteditor.h"
 
 namespace Gwenview {
 
 
 struct RedEyeReductionImageOperationPrivate {
 	QRect mRect;
 	QImage mOriginalImage;
 };
 
 
 RedEyeReductionImageOperation::RedEyeReductionImageOperation(const QRect& rect)
 : d(new RedEyeReductionImageOperationPrivate) {
 	d->mRect = rect;
 	setText(i18n("RedEyeReduction"));
 }
 
 
 RedEyeReductionImageOperation::~RedEyeReductionImageOperation() {
 	delete d;
 }
 
 
 void RedEyeReductionImageOperation::redo() {
 	QImage img = document()->image();
 	d->mOriginalImage = img.copy(d->mRect);
 	apply(&img, d->mRect);
 	if (!document()->editor()) {
 		kWarning() << "!document->editor()";
 		return;
 	}
 	document()->editor()->setImage(img);
 }
 
 
 void RedEyeReductionImageOperation::undo() {
 	if (!document()->editor()) {
 		kWarning() << "!document->editor()";
 		return;
 	}
 	QImage img = document()->image();
 	{
 		QPainter painter(&img);
 		painter.setCompositionMode(QPainter::CompositionMode_Source);
 		painter.drawImage(d->mRect.topLeft(), d->mOriginalImage);
 	}
 	document()->editor()->setImage(img);
 }
 
 
 void RedEyeReductionImageOperation::apply(QImage* img, const QRect& rect) {
 	const qreal radius = rect.width() / 2;
 	uchar* line = img->scanLine(rect.top()) + rect.left() * 4;
 	const qreal shadeRadius = qMin(radius * 0.8, radius - 1);
 	const int width = rect.width();
 	const int height = rect.height();
 	for (int y = 0; y < height; ++y, line += img->bytesPerLine()) {
 		QRgb* ptr = (QRgb*)line;
 		for (int x = 0; x < width; ++x, ++ptr) {
 			const qreal currentRadius = sqrt(pow(y - radius, 2) + pow(x - radius, 2));
 			qreal k;
 			if (currentRadius > radius) {
 				continue;
 			}
 			if (currentRadius > shadeRadius) {
-				k = (currentRadius - shadeRadius) / (radius - shadeRadius);
+				k = (radius - currentRadius) / (radius - shadeRadius);
 			} else {
-				k = 0;
+				k = 1;
 			}
 
 			QColor color(*ptr);
 			const int red1 = color.red();
 			int red2 = ( color.green() + color.blue() ) / 2;
-			red2 = int(red2 * (1. - k) + red1 * k);
+			red2 = int((1 - k) * red1 + k * red2);
 			color.setRed(red2);
 			*ptr = color.rgba();
 		}
 	}
 }
 
 
 } // namespace