Routine Test Renders Surprise Result!

For someone who enjoys testing and preaches it world wide, I should have known better.

This all started when I agreed to shoot a volleyball “skills” video for my daughter. “Skills” videos are part of a student athlete’s resume in their quest for a scholarship to a University. Volleyball is a fast game and very difficult to get close enough for a power hit and then wide enough to see the result of that “spike” in one shot.  My solution was to design a bracket that holds TWO CAMERAS, one tight and the other wide to capture two shots at once. During a match, this rig will be setup behind the baseline of the volleyball court.

Here’s the “sketch up” I gave to a local machinist.

Next - which cameras to shoot with? For the wide shot, I’ll mount the Lumix GX7 with a 12-35mm zoom. For the tight shot I’ll use the Canon 70D with a 70-200mm zoom.  (I assumed that this was my very best long lens option)  Solid choice, but after thinking about the cost of replacing the latter system if taken out by an errant volleyball - I decided to dust off my trusty Canon XA-10 for a long lens comparison test.

Surprisingly, the sizes were roughly the same at the long end of each zoom lens. Somehow, I just assumed that the camcorder would be tighter at maximum zoom. For the focus test, I taped a $5 bill on the wall and lit it for an F 2.8. Both cameras were zoomed in to fill the frame with the bill and set at the highest picture quality for 60 fps. After carefully scrutinizing the critical focus for each camera - the shots were recorded.

Upon importing, I noticed a startling difference right away. Had I mixed up the cards? Nope. The XA-10 shot seemingly looked much sharper and tonally better than the 70D! Bemused by this, I reshot the test only to get the same results. Happy that the XA-10 looked so good, but super concerned that the 70-200 or the 70D was damaged in some way - I headed off to our first rate camera store.

The first thing the tech/sales guy did was put my zoom lens on a brand new 70D and shot a still at 200mm of a focus chart at 2.8. He looked at the playback and then enlarged the image, studied it closely, showed it to me and then proclaimed, “Great lens, want to sell it?”

Next step – verify the alignment and clarity of the sensor in the 70D by shooting a RAW photo of the $5 bill. While attempting to import the test photo, Photoshop stopped me cold as you can’t manipulate US currency on their platform. So I switched to a ¼ page real estate advertisement.

Here is the focus test still photo from the 70-200 lens on the 70D camera body:

I should mention that this ad is only slightly bigger than a $5 bill and is printed as black and white for tonal consistency between the still and video formats. As you can see, this quick test is very sharp and to me, confirms that the sensor is in alignment and that the lens flange is square and properly distanced. 

For the last time, I reshot the video side by side comparison test with the real estate ad and here are the results:

To my eye, everything about the XA-10 clip looks better, type is sharper, grass – though never sharp to begin with, resolves better than the 70D clip. And what isn’t evident is how much noisier the 70D is compared to the XA-10.

The XA-10 has a great reputation and is reasonably expensive, but compared to a fine camera body in the 70D and a world class zoom lens, you have to admit – these test results confirm that the long lens camera for this project should be the Canon XA-10. Are you as surprised as I am? Keep testing! The results may surprise you too!

Return To Musings