For some time now, I've been keen to experiment with some in car video camera work, and not long ago I finally bit the bullet and ordered in a mount from Camzilla. The mount turned up a couple of days before the weekends round of the Australian Top Alcohol and Pro Stock Bike championships at the Perth Motorplex. After testing it out in my 18 second ambulance on the way home from work one day, I decided to try fitting it to a couple of cars over the course of the weekend. The first car I put the mount and camera setup into was Belinda Hay's "Mrs Canada" 383 powered VN Commodore Super Streeter. This car runs regularly in the low 11 second zone and this particular pass was completed in 11.3 seconds.
After a quick look at the footage on the back of the camera, I decided to check out the Super Sedan lineup for something a little quicker. It didn't take long before I spotted Norbert Claite's low 9 second capable "Wild Ute", a 454 cube Big Block Chev powered Ford Falcon ute. Whereas I had mounted the camera to the passenger window glass in Belinda's Commodore, in Norbert's car I decided to fix the mount to the floor. The video from Norberts car gets a little shaky at times, which I put down to vibration in the floor rather than the mount itself, which is not only part of the testing process, but also a better result than some other video I've seen shot.
The camera is a Canon (of course) Legria FS200, it's about a middle of the range consumer camera, there's a lot of cheaper stuff out there and a lot more expensove stuff. This particular one is a model without an internal hard drive (as those often fail prematurely when used in cars a lot, due to the constant vibration), it does have image stabilisation, but I suspect the IS would be even better on a more expensive camera.
The mount is a Camzilla mount, these are assembled from components from a company called Ram mounts, and they look and feel like very solid gear. This mount uses 3 large suction cups to attach it to a flat (or almost flat) surface - it can handle slight curves, like a car window. The company claim you can use these mounts on the outside of cars as well as the inside, but aside from the wind noise problems that creates, I'm still not game doing that just yet.
Thanks to both of the teams for putting up with me trying out different locations in their cars to get these shots.
Wednesday, February 3, 2010
Friday, November 27, 2009
For some time now, I've been pondering the concept of 'stacking', with regards to teleconverters for camera lenses. Recently I had the opportunity to borrow a 2x converter to supplement my 1.4x converter, and make this experiment possible.
Other people who had done similar experiments (usually bird photographers shooting smaller targets at longer distances) had reported that the loss of sharpness with the 2 converters stacked, made the exercise almost useless.
This experiment was conducted using a Canon 70-200 f/2.8L (non-IS version) fitted to a Canon EOS 1D Mk III, with a Canon 1.4x TC II and a Canon 2.0x TC II fitted between lens and body. You can only fit the converters one way round, as the rear of the 1.4x is flat, and both the converters have a short nose that fits inside the rear of the lens.
The following photo was not resized at all (it is resized for display here, but I've provided a link to the original image), only cropped down from the 1D Mk III's 10.1 megapixels. As a side note, using 2 converters does screw with the camera's brain a little, the lens seems slightly slower to focus, but still quicker than the Sigma 50-500 that I was comparing the results with. Also, the EXIF info suggests this photo was shot with only the 2x TC fitted to the 70-200L, focal length as a result is reported at 400mm, when it was actually around 560mm.
For comparison, here's a similarly treated shot, again, only cropped, not resized (except for display in this post), out of my Sigma 50-500mm (aka The Bigma).
My conclusion? Previous photographic evidence by other photographers has shown that stacking converters is probably not a good idea for bird photography, and it's probably something to be avoided where possible, as there is definatley some loss of sharpness occuring, however, when shooting motorsports, which typically involves larger targets moving at speed, the sharpness of the image is sometimes not that critical anyway, as there tends to be a bit of motion blur even at higher shutter speeds.
Would I do it again? Probably, if I had the gear at my disposal.
Would I use stacked converters over a Canon 100-400L with a 1.4x TC? Probably not, but I don't have a 100-400L or a 2x TC, so this is a bit of an irrelevant question.
Would I use stacked converters over my Sigma 50-500? I don't know. The results are close, but the winner for me has always been the Sigma's ability to zoom all the way from 50mm to 500mm, and perform pretty capably all the way through. However, the reason I'm thinking about this at all, is because my Sigma is failing, and I'm not sure it's worth repairing or replacing with another Sigma lens.