
I love my lenses, but lenses on their own don’t make the photo. Sometimes you want to see what’s behind the reflection that is being produced on the surface of the water, but sometimes you want to see what is being reflected instead. Maybe you are taking a landscape photo and you need the sky to gradually be darker to ensure that you don’t exceed the sensor’s dynamic range.
There is a specific filter for each of the situations described above, you just need to know which one is the best suited one for it.
Most of my lenses have both of those. The two exceptions are: Big Bertha (150-600mm) – in which the cheapest MC UV filter I could find costed me more than $100 – and the Sigma 20mm, which has a domed shaped lens, thus not allowing me to screw in any filters. None of what I will say below will apply to these two lenses.
I have invested some money in filters so far, but the two most used filters for me are the CPL and MC UV. For a long time, I used my Nikkor 24-85mm as my main lens. I have bought an extensive set of polaroid filters for it: MC UV, CPL, Warming, Fluorescent and Variable ND… and a few Infra-Red filters. But the more I took photos, the more I started drifting away from this lens.
My most used lens now is my prime Nikkor 50mm. Because I started using it so much, I started investing in better quality filters for it. I bought myself a Hoya CPL (NXT Plus) and it has made a difference. I know it’s not the top of the line in the Hoya family, but it does make a significant difference compared to others. So much that I started looking at the next level up: Hoya Evo Antistatic CPL Circular Polarizer Filter (Dust / Stain / Water Repellent Low-Profile Filter Frame). The price difference is significant: the Evo is 33% more expensive than the NXT Plus for my 58mm. I still want it, because of all the things it repels).
But my obsession with the 50mm won’t stop there, I want to replace the Polaroid MC UV with a Hoya one. Why? To have the most used filters for this lens in the same family. I have a MC UV and CPL pair by Gobe, which is also a decent brand, but Hoya excels in the quality, clarity and the extra bits of the filter.
I may, or may not, also get Warming and Fluorescent filters (not Hoya) for it.
I would like all my lenses to have the Hoya MC UV + CPL combo mentioned above.
And then we go into landscape photography… where we have my wide angle Nikkor lens (18-35mm) and I may also use my 50mm lens. This is where the more complex and artistic filters come into play.
So far, we have been talking about ROUND filters, that fit on the end of the lens and it becomes an invisible part of it; we only see the effects of the filter, rarely even noticing the filter is there. But landscape photography (and even architecture photography) can benefit greatly from having interesting filters applied while shooting the photo, instead of the post-process.
At this point I have come to a stand still:
Should I, or should I not buy a square/rectangular filter set?
I have been doing research on the filter sets, most of them are ND or graded ND (from no ND to an ND). This is the sort of filters that would allow for darker skies to not throw out the dynamic range in the photo. It also allows for long exposure photos where the sky is significantly brighter than the rest. Those kits, even the starting ones, are significantly expensive, some going beyond $1500.

I guess, to answer the big question above, I should ask:
- What can square filters do that circular ones can’t?
- Why are they so expensive?
- Why do professional photographers use them?
I have found a couple of pages (here and here) about the differences.
Having looked at the pros and cons and the use cases, I think I need to assess in my personal usage:
- How often am I going to use ND (Neutral Density) and GND (Gradient Neutral Density) filters to take landscape, architecture and/or long exposure photos?
- Do I really need to use filters on my Sigma 20mm lens? (Nisi has a specific holder adaptor for that lens)
- How often will I super-impose multiple filters? (Super-imposing circular filters generally causes vignettes on the photos)
- Will I be able to get (and use)”creative filters” for my work?
These are questions that I will need to think about the answer before making such a buy. I have to say that I would LOVE to put a filter on my Sigma 20mm, but the filter holder kit from Nisi specific for that lens (no filters come with the kit, it’s just the holder adapters and the filter adapters) costs $650 – for 150 mm filters – on Amazon. For all other lenses (that do not have a domed lens) that use 100 mm filters, I could probably get a 100mm kit with 2 filters for $730.
Note: I hold no rights over the photo of the Nisi filter in the post, the photo was taken from Amazon AU site.
Note 2: The prices provided are Nisi filter at Amazon AU site.
Note 3: The effect in the hero image/banner is a Lightroom preset/edit instead of a physical lens filter.