Experimenting with the Helix
Camera Testing: A How To Guide
Camera testing can be a very personal endeavor as the results one person is after may not be the same results that another person is after. It seems that no matter how carefully a test is done, there will always be critiques of how a test was conducted, and how someone else could have done it better, or that the test should have been done differently. My goal in this post is to show some test scenarios, explain how to set them up, so that you can more effectively test out your camera system for comparison or in preparation for production.
Letus Color Temp & ND Fader Test
Portland Lens Test 2011
Check out the footage for yourself and download the R3Ds after the jump...
IR ND Filtration + EPIC
As cameras get more and more sensitive to light, infrared (IR) pollution becomes a bigger issue as stronger neutral density filters are used to maintain exposure. IR pollution ends up changing the color rendition of the entire image and can result in some VERY funky color shifts. (I have seen dark green leaves change to magenta for example.) These color shifts can be next to impossible to get rid of once they are recorded into the digital image. There are creative ways to get rid of this in post, but many of these solutions - like rotoscoping and painting out the problem - are cost prohibitive. Besides, a "problem" like this should have been corrected in the camera at the time of filming, not left to post. Always remember this mantra, and practices it daily: "Fix it in camera, NOT in post."
Let's explore this in detail after the jump ...
Epic + HMI (Mag Ballast)
[HIGHLY RECOMMEND WATCHING IN FULL SCREEN]
Just because it works in theory doesn't mean it will work in practice. And just because it works in one application, that doesn't mean it will work in another application - which is why testing durring preproduction is SO important and should NEVER go over looked. I recently spent a day camera testing in preparation for a short film I was shooting for Director Shawn Nelson and it was during one of the camera tests that we stumbled upon some interesting results when shooting with the Epic and HMI's that use a magnetic ballast. What I had thought would be safe speeds on the camera turned out to not be safe at all ...
More after the jump.
Zeiss ZF.2 Lens Test Chart
[HIGHLY RECOMMEND WATCHING IN FULL SCREEN]
Charts are not very sexy I know - but they are very useful. I completed this test to evaluate where these lenses perform the best so that I can get the most out of them. When wide open, the chromatic aberration, and the slight softness that the lenses produce means that for my tastes, I'll be using them stopped down at least one stop. Once they are stopped down by one stop, everything looks sharp, and the chromatic aberration goes away. The 85mm seems to be the worst offender, as the image is not clear until around T4 / T5.6. And both the 28mm and 35mm seem to hold up better then the 50mm or the 85mm. Overall, I'm happy with the results as they bear out what I have experienced first hand when using these lenses in a production environment. I'll be using these lenses in the T2.8 - T8 range going forward.
Download the stills after the jump.
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