As landscape photographers, we rely on our filters to cut down the dynamic range of a scene. As we become serious, we want our filters to be durable, scratch resistant, 'neutral' (no color cast) and gives the highest possible image quality. Lee offers a wide range of quality filters that is affordable to most photographers.
Lee has two types of Neutral Density (ND) filters: ProGlass and Resin.
Resin is like high quality plastic. They are light and durable. They don't shatter like glass. They are cheaper than glass and is made of resin. Since they are cheap, they're a great way of filtering light on a budget before you go after the more expensive ones.
ProGlass on the other hand is heavier. They feel more solid. But since they're glass, they shatter when dropped on solid floor. Glass filters are more expensive that resin and are considered 'better'.
But better in what? By how much?
Lee’s resin filters are about $80-$100 cheaper than it’s glass counterpart. Add a little bit more cash on the difference and you’ll get a new GND or ND filter. This is really a tough choice balancing between image quality and cost. ProGlass is very tempting.
Stacking Neutral Density Filters
I happen to have a pair of Lee 0.9 Resin filter and a pair of Lee 0.9 ProGlass filter. The photos below show a control photo with four (4) other photos stacked with either a pair of resin or proglass Lee filter:
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| Control Photo, No Filters |
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| Lee 0.9 Resin Neutral Density (ND) Filter |
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| 2 x Lee 0.9 Resin Neutral Density (ND) Filter |
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| Lee 0.9 ProGlass Neutral Density (ND) Filter |
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| 2 x Lee 0.9 ProGlass Neutral Density (ND) Filter |
Looking at the photos above, the difference are very subtle. I can say that image quality (IQ) is not affected. Even if there are 1 or 2 filters (resin or proglass) at the front of the lens, all photos are sharp. Thus I don't question this area.
In terms of color, both resin and proglass maintain color integrity. The colors shown by Lee Resin filters are close to that of the control photo. This is very acceptable. There maybe a slight color shift, but it's negligible and can be ignored. This color shift from the resin filters can be clearly detected by side by side comparison with the control photo. The colors of Lee ProGlass filters are the closest to the control photo. Although I favour the colors of ProGlass, I could live with the results of the resin filters.
Just an experiment, I mixed a Lee 0.9 Resin ND filter with a Lee 0.9 ProGlass ND filter. The result below is excellent: |
| Mix of a Lee 0.9 Resin Filter and a Lee 0.9 ProGlass Filter |
Stacking Different Filters
I believe the challenge comes when mixing different filters together. You don't usually stack 2 or 3 0.9 (3 stops) filters together. You usually stack a Grad ND, ND, and CPL altogether. I got a bunch of commonly used filters and stack them to resin and ProGlass.
Heliopan 105mm Circular Polarizer (CPL) is one popular filter. It cuts down reflections when rotated properly. I borrowed this CPL and the results are below. Note that when mounting a Heliopan 105mm CPL, you can only add one (1) more square filter. A friend of mine hacked his filter holder to accommodate 2 square filters. But commercially (without hacking or DIY), you can only mount 1, thus I only tested with either one (1) resin or one (1) ProGlass ND filter.
Control Photo:
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| Control Photo, no filters |
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| Heliopan 105mm CPL |
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| Heliopan 105mm CPL + Lee 0.9 Resin ND Filter |
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| Heliopan 105mm CPL + Lee 0.9 Prolass ND Filter |
Heliopan's 105mm CPL is a highly regarded CPL filter. Comparing Control and the CPL gives a very similar result in terms of sharpness. What differs are the colors. CPL managed to saturate the blue sky and enrich the colors a bit (see the glass and leaves).
An added bonus with a CPL is that it cuts down reflections from transparent medium (e.g. glass). In this case, water is the transparent medium. Since the reflections are reduced, the details beneath the water can be seen.
Another useful filter is either the soft edge or hard edge Neutral Density filters. Since I don't have a clear cut horizon, I used a Lee 0.6 soft edge ND filter. Below are the results:
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| Control Photo at St Mary's Cathedral |
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| Lee 0.6 Resin Grad ND Filter |
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| Lee 0.6 Resin Grad ND + Lee 0.9 Resin ND |
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| Lee 0.6 Resin Grad ND + Lee 0.9 ProGlass ND |
Looking closely at the photos, I don't have an issue with sharpness. Lee does make quality filters! With a Lee 0.6 Graduated Neutral Density (ND) filter in front of the lens, the sky darkens a bit. I first inserted a Lee 0.9 Resin ND, followed by a Lee 0.9 ProGlass. ProGlass is better and is closest to the control photo, but the resin is trailing in close. Without photos to compare it to, you won't see the slight color shift from the resin.
When I was shooting at St. Mary's Cathedral, I had with me the following filters:- Hitech 0.9 ND filter (3 stops)
- Hitech 1.8 ND filter (6 stops)
Hitech is also a popular among filters. Although I believe that Lee has more quality, other photographers are satisfied with Hitech. For the sake of comparison, I added some photos here taken with Hitech filters.
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| Lee 0.6 Resin Grad ND + Hitech 0.9 ND |
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| Lee 0.6 Resin Grad ND + Hitech 1.8 ND (6 stops) |
I don't see any significant sharpness drop. For the Hitech 0.9 ND, it's pretty close with the control photo. For the 6 stop (1.8 ND), Hitech introduces a strong bluish and greenish color cast. This can still be recovered at post. But keep in mind that Hitech offers a 6 stop, in which Lee only introduces this filter recently (Little Stopper). It is a bit unfair to compare Hitech's 6 stop as the higher the filtering power, the more/stronger the color cast it introduces.
For more comparisons, please refer to the photos below:
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| Control Photo at Darling Harbour |
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| Lee 0.6 Resin Soft Grad ND Filter |
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| Lee 0.6 Resin Soft Grad ND Filter + Lee 0.9 Resin ND Filter |
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| Lee 0.6 Resin Soft Grad ND Filter + Lee 0.9 ProGlass ND Filter |
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| Control Image at Long Reef Reserve |
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| Heliopan 105mm Circular Polarizer (CPL) only |
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| Heliopan 105mm CPL + Lee 0.9 Resin ND filter |
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| Heliopan 105mm CPL + Lee 0.9 ProGlass ND Filter |
*Note - for photos above taken at Long Reef, please don't compare sharpness on the grass and clouds. It's windy that time.
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| Control Photo at Long Reef |
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| Lee 0.9 Resin ND Filter |
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| 2 x Lee 0.9 Resin ND filter |
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| Lee 0.9 ProGlass ND Filter |
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| 2 x Lee 0.9 ProGlass ND Filter |
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| 3 x Lee 0.9 ProGlass ND Filter !! |
Final Thoughts
Lee's ProGlass Neutral Density filters are better than it's Resin counterpart. I don't see any difference in sharpness between ProGlass and Resin and I don't see any degradation of sharpness from both when compared to a control image.
Where ProGlass shines is color integrity. There is minimal to no color shift when using a ProGlass. When you stack ProGlass with each other, they produce very similar color results. The photo above shows 3 stacked 0.9 ProGlass filters which you could directly compare to a 1 or 2 stacked 0.9 ProGlass filters. Mixing ProGlass with other filters (e.g. CPL, Grad ND) holds it own and does not pose any issues.
Although ProGlass is better, Lee's Resin filters are trailing close behind. For me, the slight color shift of resin filters is not noticeable on the field. Even if you make a side by side comparison, the difference is not that big. When stacked with each other, resin filters tend to degrade more quickly than ProGlass. I don't see any issues when mixing resin filters to other filters (e.g CPL, Grad ND)
Again, Lee's ProGlass is better than Lee's Resin filters. In my opinion, the difference is not that huge, but for someone who wants ultimate image quality, ProGlass is the way to go. Given the funds, I'd go with ProGlass. But if you're short in cash with many other filters lined up to be bought, Lee's Resin filters are fine.
I use Lee's Resin filters and I don't have the urge to upgrade to ProGlass.
