In the last article, we introduced the concept of using a Reverse Neutral Density Graduated filter into post-processing via the Graduated Filter in Adobe’s Lightroom product. Today, we expand that examination by looking at a comparison of the effect compared to the glass filter.
First a shout out to my friend Alec Johnson for providing me with the sample images for today’s article. Thank you, Alec. Check out Alec’s work at his website.
In Alec’s original capture, the foreground was subdued to hold the detail in the sky.
In Alec’s second capture, he used a Singh-Ray Reverse Neutral Density Graduated Filter with a 1.0 stop rating. The Singh-Ray filter features a moderate transition zone at the typical horizon and tapers from a one-stop filter to nearly clear at the top. Depending upon how you frame your horizon and place the filter, some darkening can occur at the top of the frame – which Alec indicates happened here. The horizon is above mid-frame and the filter’s transition,when placed on the horizon would cause the entire top portion of the frame to darken somewhat.
It looks like Alec boosted his exposure by about a half stop to allow his foreground to jump out a bit in his final capture.
This is a Lightroom Virtual Copy of Alec’s original unfiltered exposure. I have increased the exposure until the foreground matches exposure with the second filtered capture. I can’t match it exactly but it is pretty darn close to a +0.50 Exposure slider. This gives us a good place to apply the Lightroom-based Reverse Graduated Neutral Density preset.
This is a virtual copy of the Lightroom boosted exposure with the Reverse Graduated 1.0 to 0.0 preset applied. After applying the preset, the constituent graduated filters were adjusted for the image’s framing.
Here is a quick before after view for comparison:Filtered in Field on the Left and Filtered in Lightroom on the right. I suspected the original captures varied in White Balance and this examination bears that out. With the exception of the warmth of the original filtered capture, the tonal values are pretty close. The remaining variance is easily explained by transition zone size and placement which is a very manual process in the field. Lightroom allows a greater precision in post on exactly how straight and where that transition occurs.
Here is the same image with software-corrected White Balance. Getting closer…
You will always hear me say that getting it close in the field is better than correcting in post –processing. This example is no different.
The Lightroom method has its advantages. You can adjust your filter after the fact for straightness, position, and Neutral Density value. It can be duplicated across many images. It doesn’t need to be kept clean like a glass filter. It isn’t subject to internal reflections like phantom moons and the like. You also don’t experience the cost of the filter, holding apparatus and bag space.
The Singh-Ray has its advantages as well. You can push those darker areas lighter in the field when you are actually blocking the bright light. Overall, your dynamic range increases at capture and that makes for cleaner post-processing and less noise by allowing your exposure to push farther right. And, if you are a SOOC fiend, you will be happier with your capture when using this filter properly.
If you carry the Singh-Ray’s by all means use them. You will get superior images to no filter. If you don’t have them, this Lightroom technique can give your post processing a leg up. In a Rikk-minded world, both have their place and there is strength in combining both.
I will be making my Reverse Graduated Filter Presets available in the next article so stand by! A little instructional video will be needed…
Rikk Flohr © 2014