diff --git a/camerapreview.cpp b/camerapreview.cpp
index 99d7ed6..8257b03 100644
--- a/camerapreview.cpp
+++ b/camerapreview.cpp
@@ -14,28 +14,28 @@ CameraPreview::CameraPreview(QWidget *parent):cameraname(""), camera(nullptr), Q
     QWidget *controls = new QWidget(this);
 
     width = new QSpinBox(controls);
-    width->setSingleStep(4);
-    width->setMinimum(4);
+    width->setMinimum(32);
     width->setMaximum(2048);
+    width->setSingleStep(32);
     width->setValue(width->maximum());
     connect(width, SIGNAL(textChanged(QString)), SLOT(updateWidth(QString)));
 
     height = new QSpinBox(controls);
-    height->setSingleStep(4);
-    height->setMinimum(4);
+    height->setSingleStep(32);
+    height->setMinimum(32);
     height->setMaximum(1536);
     height->setValue(height->maximum());
     connect(height, SIGNAL(textChanged(QString)), SLOT(updateHeight(QString)));
 
     xoffs = new QSpinBox(controls);
-    xoffs->setSingleStep(4);
+    xoffs->setSingleStep(8);
     xoffs->setMinimum(0);
     xoffs->setMaximum(2047);
     xoffs->setValue(0);
     connect(xoffs, SIGNAL(textChanged(QString)), SLOT(updateXoffs(QString)));
 
     yoffs = new QSpinBox(controls);
-    yoffs->setSingleStep(4);
+    yoffs->setSingleStep(8);
     yoffs->setMinimum(0);
     yoffs->setMaximum(1535);
     yoffs->setValue(0);
@@ -57,12 +57,11 @@ CameraPreview::CameraPreview(QWidget *parent):cameraname(""), camera(nullptr), Q
     this->layout()->addWidget(controls);
     //setPrimaryCamera(devicename);
     qDebug() << "Camera preview constructor";
-    takeStill();
 }
 
 
 void CameraPreview::setCamera(QString &device){
-    qDebug() << "update camera! ";// << device.toStdString();
+    qDebug() << "update camera! " << device;
     cameraname = device;
     if (camera != nullptr) {
         qDebug() << "camera is not nullptr! ";
@@ -81,7 +80,26 @@ void CameraPreview::setCamera(QString &device){
         msgBox.exec();
         return;
     }
+    int64_t max_height = camera->sensorHeight();
+    int64_t max_width = camera->sensorWidth();
+    std::cerr << "set spin box values " << max_width << " " << max_height << std::endl;
+    width->blockSignals(true);
+    height->blockSignals(true);
+    xoffs->blockSignals(true);
+    yoffs->blockSignals(true);
+    width->setMaximum(max_width);
+    width->setValue(max_width);
+    height->setMaximum(max_height);
+    height->setValue(max_height);
+    xoffs->setMaximum(max_width - 1);
+    xoffs->setValue(0);
+    yoffs->setMaximum(max_height - 1);
+    yoffs->setValue(0);
     label->setText(device + " - " + camera->userName());
+    width->blockSignals(false);
+    height->blockSignals(false);
+    xoffs->blockSignals(false);
+    yoffs->blockSignals(false);
     takeStill();
 }
 
@@ -89,12 +107,14 @@ void CameraPreview::setCamera(QString &device){
 void CameraPreview::takeStill() {
     qDebug() << "Take Still image!";
     if (camera != nullptr && camera->isOpen()) {
-      MyImage mimg;
+      ImageSettings s = camera->getImageSettings();
+      MyImage mimg(s.width, s.height);
       bool valid = camera->grabFrame(mimg);
       if (!valid) {
           qWarning() << "Grabbing from camera failed!";
           return;
       }
+      qDebug() << "Grabbed image from camera succeeded!";
       QImage img(static_cast<uchar *>(mimg.data()), mimg.width(), mimg.height(),
                  QImage::Format::Format_Grayscale8);
       QPixmap mpm = QPixmap::fromImage(img);
@@ -115,7 +135,7 @@ void CameraPreview::updateWidth(QString s) {
     // if (xoffs->value() + width->value() > 2048) {
     //     xoffs->setValue(2048 - width->value());
     // }
-    validate(width, xoffs, 2048);
+    validate(width, xoffs, camera->sensorWidth());
     updateROI();
 }
 
@@ -123,7 +143,7 @@ void CameraPreview::updateXoffs(QString s) {
     // if (xoffs->value() + width->value() > 2048) {
     //     width->setValue(2048 - xoffs->value());
     // }
-    validate(xoffs, width, 2048);
+    validate(xoffs, width, camera->sensorHeight());
     updateROI();
 }
 
@@ -131,7 +151,7 @@ void CameraPreview::updateHeight(QString s) {
     // if (height->value() + yoffs->value() > 1536) {
     //     yoffs->setValue(1536 - height->value());
     // }
-    validate(height, yoffs, 1536);
+    validate(height, yoffs, camera->sensorHeight());
     updateROI();
 }
 
@@ -139,16 +159,18 @@ void CameraPreview::updateYoffs(QString s) {
     // if (height->value() + yoffs->value() > 1536) {
     //     height->setValue(1536 - yoffs->value());
     // }
-    validate(yoffs, height, 1536);
+    validate(yoffs, height, camera->sensorWidth());
     updateROI();
 }
 
 void CameraPreview::validate(QSpinBox *origin, QSpinBox *dest, int limit){
+    qDebug() << "validate";
     int val = ensureDivbyfour(origin->value());
     origin->setValue(val);
     if (origin->value() + dest->value() > limit) {
         dest->setValue(limit - origin->value());
     }
+    qDebug() << "validate done";
 }
 
 int CameraPreview::ensureDivbyfour(int val) {
@@ -160,6 +182,7 @@ int CameraPreview::ensureDivbyfour(int val) {
 }
 
 void CameraPreview::updateROI(bool emitSignal) {
+    qDebug() << "Update roi with signal: " << emitSignal;
     QImage img = pm.toImage();
     double scaling = 800.0 / img.width();
     img = img.scaledToWidth(800);
@@ -176,20 +199,24 @@ void CameraPreview::updateROI(bool emitSignal) {
     int rheight = round(height->value() * scaling);
     qPainter.drawRect(rxoffs, ryoffs, rwidth, rheight);
     bool bEnd = qPainter.end();
-
     QPixmap npm = QPixmap::fromImage(img);
     setImage(npm);
     if (emitSignal) {
         emit roiUpdated(xoffs->value(), yoffs->value(), width->value(), height->value());
     }
+    qDebug() << "update ROI done";
 }
 
 void CameraPreview::setSize(int w, int h) {
+    qDebug() << "set size " << w << " " << h;
     width->setValue(w);
     height->setValue(h);
-    validate(width, xoffs, 2048);
-    validate(height, yoffs, 1536);
+    if (camera != nullptr && camera->isOpen()) {
+        validate(width, xoffs, camera->sensorWidth());
+        validate(height, yoffs, camera->sensorHeight());
+    }
     updateROI(false);
+    qDebug() << "set size done";
 }
 
 QString CameraPreview::device(){
@@ -198,12 +225,14 @@ QString CameraPreview::device(){
 
 ROI CameraPreview::getRoi() {
     ROI r;
+    uint32_t max_height = camera->sensorHeight();
+    uint32_t max_width = camera->sensorWidth();
     r.x = xoffs->value();
     r.y = yoffs->value();
     r.width = width->value();
     r.height = height->value();
-    r.height = r.height > 1536 ? 1536 - r.y : r.height;
-    r.width = r.width > 2048 ? 2048 - r.x : r.width;
+    r.height = r.height > max_height ? max_height - r.y : r.height;
+    r.width = r.width > max_width ? max_width - r.x : r.width;
     return r;
 }