Help - Chromatic Aberrations Voigtlander 10.5

I have a question i just purchased my second lens for the BMPCC and i get very different results in the area of color aberrations. My first lens was a voigtlander 17.5mm (i've had for a while) my new lens is a voigtlander 10.5mm. On a shoot last weekend i used both lenses indoors with LED lights. There was a poster 4ft x 3ft with black text on white background. Taken from about the same distance, on a fixed tripod. The 17.5 did fine. the 10.5 was horrible. Each word on the poster was a different color some green some blue, some red, some were a mixture. None were black text. Do the lights im using only effect only the 10.5? Does the 10.5 not work with the BMPCC? Im on limited budget any help would be appreciated. Is my lens broken? Did the seller send me a lemon? Have i spent my money on the wrong lens?

Sincerely no offense intended. I've never seen anything like that from a lens. Return the lens.


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It's not a chromatic aberration. It's a severe moire. It means that your lens is too good (too sharp) for this camera. Maybe some effects ow PWM LED controller are present too but I am almost sure it's not so. Unfortunately all Blackmagic cameras suffer from this effect due to absence of an optical low pass filter.

I had this problem many times but I've never expected so serious problem.

Blackmagic intentionally omitted the OLPF in their cameras since it negatively affects the image quality in most situations. Your situation is exceptional.

1) To exclude any problems from LED try using maximum angle and/or other lights.

2) Change the distance from the object.

3) Use some external optical low pass filter.

4) Slightly spoil a focus.

5) Sell this lens and buy something of less quality and correspondingly cheaper.

6) Buy a 4K (4.6K) BM camera. The more pixels the less the effect.

7) 3CCD, 3CMOS and Foveons should not suffer from it by design. But they have their own problems. Lots of problems.

8) If nothing helps buy something maximally expensive with maximal pixel count from any well known brand. If they interpolate correctly then the effect would be suppressed almost fully. The price would be the loss of cinema RAW, and the MP4 format quality is OK for 99.9 per cent of all humans.

PS. I am not a professional cinematographer. I am a Russian physicist so I possibly understand the physics of the process.

PS. I am not a professional cinematographer. I am a Russian physicist so I possibly understand the physics of the process.

Anatoly, I'm really glad to have you on this forum!

BTW : If you use RAW, try different color interpolation methods in your RAW processor. Different methods give different artifacts and some methods may give a satisfactory image.

Thanks, Anatoly. I never thought it was traditional chromatic aberration, but just something very weird with the glass (imperfections in the glass?). I've never seen moiré do that, but appreciate your astute judgment.


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It's not a chromatic aberration. It's a severe moire. It means that your lens is too good (too sharp) for this camera.

Interesting to hear this. Years back I can remember taking a verbal beating from some shooters because I presented video tests that were shot with a wide convertor and common lens. I was derided for you cheap lenses on my Blackmagic camera. I made the same point you make here, suggesting that some lenses can contribute to image problems because they are too good. I am not a physicist, however, and had nothing to back that up.

Looks like moire...

Perhaps consider adding a tracking mask and eliminating the saturation; effectively creating a perfect white balance. Then, add some tint back to the image to match surrounding shots...

Doesn't look like moire...

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