In this section I would like to present my findings regarding the behaviour of my filters when used against a bright light source.
This is the subject:
The Zeiss Planar T* 50/1.4 lit with the 5’500K lamp from the colour cast tests.
I used my CREE flashlight (“torch” for the other English faction) with a 3,3V Li-Ion battery (puts out about 300lm) to simulate the sun in a really bad spot in the image frame. I then set up my camera and experimented with the placement of the “sun” until I got the maximum amount of flare (Thank you Canon for live view!).
The pictures were shot at f/5.6, because I forgot that flaring is reduced when stopping down, but I got more than enough flares to show off.
The camera settings were not always identical (due to different absorption ratios of the filters) but I tried to adjust brightness to the same level in all images, despite the sometimes massive haze that was induced by the “sun”.
The pictures were processed identically as to reduce highlight clipping and adjust white balance (you’ll see the colour cast introduced by the filters again).
Color-Ultron no filter
First off, the Color-Ultron isn’t really a great performer regarding the handling of flare, with some haze – reducing contrast – and intense light rays but only some small blobs.
Samyang 35mm f/1.4 no filter
The Samyang is a good performer contrast-wise, although it produces weird prismatic shapes when aimed directly at the light source. Keep in mind that my test was aimed at producing the strongest flares possible. In reviews, e.g. by Lenstip, the Samyang fared quite well.
Let’s start with the UV filters
And here are the images with the Cree aimed directly at the lens, held in place by an almost antique Joby Gorillapod on a light stand.
The Hoya HD Protector again shines with a really nice performance and almost no additional flare.
The cheap Hama UV390 filter performs even worse than the K&F UV filter but both are quite astonishingly terrible at their job.
The Rollei Skylight filter performed okay but I guess you can see its age and the lack of good coatings, but the haze and the manifestation of blobs isn’t as bad as with the UV filters.
We don’t need to talk about the purple (FDL) filter. It’s bad, but then again it was never intended to be used in sunlight or aimed at the sun. It’s supposed to be used indoors with artificial lighting.
The K&F Concept CPL
You can see that the polarizer reduces the intensity of the flashlight only (the brightness on the Zeiss is approximately the same) and especially its reflection on the stone floor. I guess it works as a polarizer after all. On the other hand, the polarizer introduces nasty blobs and an additional flare-ray that rotates with the polarizer.
What about the ND filters from the chinese slide-in system TIAN YA?
Here are the samples for the Hoya HD CPL (at 90°), the Haida ND3.0 1’000x filter and the TIAN YA ND Grad.
Again, the polarizer works at reducing reflections off the stone floor. Contrary to the cheap K&F polarizer though, the Hoya HD CPL doesn’t introduce any noticeable flares in addition to the already present ones.
The Haida ND3.0 fares quite okay with just a few blobs and no major hazing or any other weird stuff going on.
The TIAN YA ND Grad is absolutely unusable against bright light. I cleaned it before this test but I would expect such a result from a filter smeared with greasy finger prints.
As you can see when looking at the images without any filters attached to the lenses, I didn’t go easy on my test subjects.
Regarding flares it seems obvious that the quality filters from Hoya’s HD series are worth their money. And I will certainly keep on putting Protector filters on my lenses.
The cheap UV and Skylight filters in my test can finally be ruled out and should be avoided for digital photography.
The Haida ND3.0 filter performed quite well and will certainly do good enough for my requirements but “serious” landscapers might want to invest in the “real thing” from LEE Filters.
The TIAN YA solid ND filters are just okay but I might not be using the K&F solid NDs much. I will also stay away from the TIAN YA ND grad.
The K&F Polarizer is perfectly useable if you’re not shooting against a light source. For instance, using it in the woods might be quite rewarding.