diff --git a/src/render.rs b/src/render.rs
index dcd175f..46af665 100644
--- a/src/render.rs
+++ b/src/render.rs
@@ -60,7 +60,9 @@ struct RenderSteps<'a> {
 
 impl<'a> RenderSteps<'a> {
     fn render(state: &'a SimSnapshot, measurements: &'a [Box<dyn AbstractMeasurement>]) -> RgbImage {
-        let mut me = Self::new(state, measurements);
+        let width = 768;
+        let height =  width * state.height() / state.width();
+        let mut me = Self::new(state, measurements, width, height);
         me.render_scalar_field(10.0,  false, 2, |cell| cell.mat().conductivity().mag());
         me.render_scalar_field(100.0, true,  0, |cell| cell.mat().m().mag());
         if false {
@@ -73,16 +75,20 @@ impl<'a> RenderSteps<'a> {
         me.render_measurements();
         me.im
     }
-    fn new(sim: &'a SimSnapshot, meas: &'a [Box<dyn AbstractMeasurement>]) -> Self {
-        let w = sim.width();
-        let h = sim.height();
+    fn new(sim: &'a SimSnapshot, meas: &'a [Box<dyn AbstractMeasurement>], width: u32, height: u32) -> Self {
         RenderSteps {
-            im: RgbImage::new(w, h),
+            im: RgbImage::new(width, height),
             sim,
             meas
         }
     }
 
+    fn get_at_px(&self, x_px: u32, y_px: u32) -> &Cell {
+        let x_sim = x_px * self.sim.width() / self.im.width();
+        let y_sim = y_px * self.sim.height() / self.im.height();
+        self.sim.get((x_sim, y_sim).into())
+    }
+
     //////////////   Ex/Ey/Bz configuration ////////////
     fn render_b_z_field(&mut self) {
         self.render_scalar_field(1.0e-4, true,  1, |cell| cell.b().z());
@@ -104,8 +110,8 @@ impl<'a> RenderSteps<'a> {
     }
 
     fn render_vector_field<F: Fn(&Cell<mat::Static>) -> Point>(&mut self, color: Rgb<u8>, typical: Flt, measure: F) {
-        let w = self.sim.width();
-        let h = self.sim.height();
+        let w = self.im.width();
+        let h = self.im.height();
         let vec_spacing = 10;
         for y in 0..h {
             for x in 0..w {
@@ -121,11 +127,11 @@ impl<'a> RenderSteps<'a> {
         }
     }
     fn render_scalar_field<F: Fn(&Cell<mat::Static>) -> Flt>(&mut self, typical: Flt, signed: bool, slot: u32, measure: F) {
-        let w = self.sim.width();
-        let h = self.sim.height();
+        let w = self.im.width();
+        let h = self.im.height();
         for y in 0..h {
             for x in 0..w {
-                let cell = self.sim.get((x, y).into());
+                let cell = self.get_at_px(x, y);
                 let value = measure(cell);
                 let scaled = if signed {
                     scale_signed_to_u8(value, typical)
@@ -162,15 +168,15 @@ impl<'a> RenderSteps<'a> {
 
     fn field_vector<F: Fn(&Cell<mat::Static>) -> Point>(&self, xidx: u32, yidx: u32, size: u32, measure: &F) -> Point {
         let mut field = Point::default();
-        let w = self.sim.width();
-        let h = self.sim.height();
+        let w = self.im.width();
+        let h = self.im.height();
         let xstart = xidx.min(w);
         let ystart = yidx.min(h);
         let xend = (xstart + size).min(w);
         let yend = (ystart + size).min(h);
         for y in ystart..yend {
             for x in xstart..xend {
-                field += measure(self.sim.get((x, y).into()));
+                field += measure(self.get_at_px(x, y));
             }
         }
         let xw = xend - xstart;
@@ -211,25 +217,25 @@ pub trait Renderer {
     }
 }
 
-pub struct NumericTermRenderer;
-
-impl Renderer for NumericTermRenderer {
-    fn render(&mut self, state: &SimSnapshot, _measurements: &[Box<dyn AbstractMeasurement>]) {
-        for y in 0..state.height() {
-            for x in 0..state.width() {
-                let cell = state.get((x, y).into());
-                print!("           {:>10.1e}", cell.ex());
-            }
-            print!("\n");
-            for x in 0..state.width() {
-                let cell = state.get((x, y).into());
-                print!("{:>10.1e} {:>10.1e}", cell.ey(), cell.bz());
-            }
-            print!("\n");
-        }
-        print!("\n");
-    }
-}
+// pub struct NumericTermRenderer;
+// 
+// impl Renderer for NumericTermRenderer {
+//     fn render(&mut self, state: &SimSnapshot, _measurements: &[Box<dyn AbstractMeasurement>]) {
+//         for y in 0..state.height() {
+//             for x in 0..state.width() {
+//                 let cell = state.get((x, y).into());
+//                 print!("           {:>10.1e}", cell.ex());
+//             }
+//             print!("\n");
+//             for x in 0..state.width() {
+//                 let cell = state.get((x, y).into());
+//                 print!("{:>10.1e} {:>10.1e}", cell.ey(), cell.bz());
+//             }
+//             print!("\n");
+//         }
+//         print!("\n");
+//     }
+// }
 
 pub struct ColorTermRenderer;
 
@@ -316,16 +322,7 @@ impl MultiRenderer {
     }
 
     pub fn render(&mut self, state: &SimState, measurements: &[Box<dyn AbstractMeasurement>]) {
-        let max_width = 1980; //< TODO: make configurable
-        //let max_width = 100;
-        if state.width() > max_width {
-            let dec = (state.width() + max_width - 1) / max_width;
-            let snap = state.snapshot(dec);
-            // XXX: measurements are messed up by rescaling
-            Renderer::render(self, &snap, &[]);
-        } else {
-            Renderer::render(self, &state.snapshot(1), measurements);
-        }
+        Renderer::render(self, &state.snapshot(1), measurements);
     }
 }