dpullum wrote:
Variable IR filter has negatives: "Although the concept is intriguing in reality though the results are quite poor and it’s all due to physics. The way these filters are made is by taking a simple variable ND filter, which is a sandwich of 2 types of polarizers and adding a red longpass filter on top of the stack. At this point some of you may already have figured out the issues just from reading the previous sentence. That’s right, all the problems you experience with variable ND filters transfer over and are made worse with the capture of two different light spectrums, visible and infrared.
https://www.lifepixel.com/photography-gear/variable-infrared-filters
The dreaded cross pattern is just as bad here, gets progressively worse the stronger IR effect you dial in. Also, because of the qualities of stacked polarizing filters you also induce a lot of softness to the image, washing out fine detail considerably..."
Variable IR filter has negatives: "Although t... (
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After using it and looking at the results in post, you are right in your observations. Funny enough, though, I step on these files so much in PS, the limitations are not so evident...though softness is for sure. But if I create a piece and hang it on a wall, well, very few would geek to our extant, eh? ;0)