Sometimes we get so hung up on sharpness that we forget just how great a bit of blur can be. Dial in a long exposure setting on your camera and motion blur can give an ethereal look to waterfalls, and smooth the surface of rivers, lakes or even the sea. Elsewhere, long exposures are also great for blurring passing vehicles and pedestrians, effectively erasing them from bustling city scenes. But how can you use a really slow shutter speed in bright daylight, without getting massively overexposed images?
The answer comes in the form of the ND neutral density filter. Sometimes a stop ND filter will be too powerful. For example, you might want to take portraits on a sunny day, using a wide aperture to give a tight depth of field that blurs the background. Many manufacturers now make ND filters in a large range of stopping powers, from a single stop to 10 stops or even more. Many manufacturers now make ND filters in a wide range of stopping powers, from a single stop to 10 stops or even more — you may need to get two or three different densities to suit your needs.
These are constructed from a pair of polarizing filters and, when one is rotated against the other, you can typically adjust the stopping power between two and eight stops. Regular ND filters tend to enable better image quality for stills photography and are more straightforward to use, while fader filters are generally more popular with videographers.
A major buying consideration is whether to go for square filters that mount in a holder and attach to the lens via an adaptor ring, or to buy circular screw-in filters. A range of basic adapter rings can also make it easier to use square filters with a variety of lenses that have different attachment thread sizes. This is because the viewfinder image can be very dark with the filter fitted, even under bright sunlight.
Square filters are therefore more straightforward to use, as you simply need to slide them in and out of the holder, rather than repeatedly screwing them onto the lens and unscrewing them again.
However, with digital cameras becoming increasingly proficient in Live View mode, it can be easier to fit the filter and then to use the rear LCD or electronic viewfinder, if featured for shooting.
Construction quality is good, based on a slim-profile brass mount with a black anti-reflective coating. As usual, larger sized filters are more expensive to buy, and not all densities are available in all sizes.
Performance is good overall, but we experienced a noticeable red color shift during our tests. Cokin made the square filter system famous, as well as bringing creative filters to the masses. While many Cokin filters are plastic or resin, these are made from Schott mineral glass with a nano-structure metallic alloy coating, to optimize light transmittance while minimizing reflections.
They proved very effective in our tests, with minimal color shift. Based in Wales, the Formatt Hitech company manufactures a wide range of high-quality filters, and its Firecrest ND filters come in a wider range than most. For starters, you can choose between square or circular options.
Square filters are available in five popular sizes to fit pretty much any holder type, and in everything from 1-stop to stop densities, in single-stop increments.
Then there are Firecrest 13 and 16 options, with stop and stop ultra-high-density ratings respectively. Again, single-stop increments are available between 1-stop and stop, while the stop and stop circular filters are available in 72mm, 77mm and 82mm sizes. They preformed extremely well in our tests, with excellent color accuracy.This traditional style of filter utilises a holder that attaches to the front of your camera and then enables you to slot in your desired filter.
Be that grad, ND, polariser or otherwise. This style of system is ideal for landscape photographers. This type of filter system has the advantage of the flexibility and is available in a variety of sizes and formats to suit your camera type.
All systems in the category work in much the same way, with some slight variations in the design. The system is based around a holder that with the addition of an adapter screws onto the front of your lens. Once in place filters can be slotted or clipped onto the front.
Lee has a long history of producing high-quality premium filters and supplies their range to both the photographic and film industry. The system is simple and easy to use with the ability to stack filters adjust exposure times as you need.
Although Lee is an aspirational brand they cater well for all levels of photographer with the premium glass and also an entry-level resin range. Both ranges use the same filter holders.
If you think that Benro just makes tripods the think again. Not only that but the filters are available in both Glass and Resin. Benro have also made the desision to release two different filter holders for the popular mm format. The budget FG is of an all plastic design and is aimed at those just getting into using filter systems. The new holder clips in the mm filters and then using a turn screw enables you to raise and lower them with accuracy.Neodymium - A METAL Is Used to Make MAGNETS!
This system is ideal for use with ND Grads enabling you to easily align the grad with horizons without having to battle with the filters with cold hands.
Cokin are the name that many people will know when it comes to filter systems. They meet that fine balance between quality and price. Recently the entire range has had an overhaul and the old names, design and quality have all been upgraded to meet the high-resolution demands of the digital camera.
The simplicity of the range is aimed at Pro Photographers who know exactly what they need to get the job done. They have a decent sized range and the quality of the glass is right up there amongst the best. This quality is also reflected in the price. The Hybrid Pro filters essentially combine neutral density and polarizer filters into one. The Hybrid Pro filters range for interchangeable lens cameras uses a multi-coated, anti-reflective glass within a lightweight aluminium frame.
Accessory Reviews. Best camera filter systems in Physical filters can make a huge difference to you image quality. From balancing to extending exposure here are the Best Filter Systems you can buy today. Buyers Guide. Thursday January 30, By Ali Jennings. Camera filters come in a variety of types: screw-in, square, rectangular and even software.It is used in safety glasses for glassblowing and blacksmithingespecially with a gas propane -powered forgewhere it provides a filter that selectively blocks the yellowish light at nm emitted by the hot sodium in the glass, without having a detrimental effect on general vision, unlike dark welder's glasses.
The strong infrared light emitted by the superheated forge gases and insulation lining the forge walls is also blocked thereby saving the crafters' eyes from serious cumulative damage such as glassblower's cataract. The usefulness of didymium glass for eye protection of this sort was discovered by Sir William Crookes. Didymium photographic filters are often used to enhance autumn scenery by making leaves appear more vibrant.
It does this by removing part of the orange region of the color spectrum, acting as an optical band-stop filter. Unfiltered, this group of colors tends to make certain elements of a picture appear "muddy". These photographic filters are also used by nightscape photographers as they absorb part of the light pollution caused by sodium street lights.
Didymium was also used in the sodium vapor process for matte work due to its ability to absorb the yellow color produced by its eponymous sodium lighting. Didymium is also used in calibration materials for spectroscopy. Didymium was discovered by Carl Mosander in Mosander did as well as could be expected at the time, since spectroscopy had not yet been invented.
Didymium had not been difficult to find, since it was providing the pinkish tinge to the salts of ceria when in trivalent form. During the period when didymium was believed to be an element, the symbol Di was used for it. In the illustration of Mendeleev's first attempt at a periodic table, shown on the right, the atomic weights assigned to the various lanthanides, including didymium, reflect the original belief that they were divalent.
InPer Teodor Cleve deduced that didymium was made up of at least two elements. Then inCarl Auer von Welsbach succeeded in separating salts of the last two component elements,   which were soon named praseodymium and neodymium.
The name of "didymium" lived on in untruncated version, partly due to the use in glassblower's goggles.
During World War Ididymium mirrors were reportedly used to transmit Morse Code across battlefields. The name "didymium" continued to be used in the rare earth metal industry. In the US, commercial "didymium" salts were what remained after cerium had been removed from the natural products obtained from monaziteand thus it contained lanthanumas well as Mosander's "didymium".These PTFE filters offer superior handling and minimal fiber slough-off compared to glass and quartz filters.
Naturally hydrophobic, the media will separate aqueous from non-aqueous phases of mixtures. Related Products: Teflon Filter.
The 90mm holder…. Related Products: Filter Funnel 90mm. These borosilicate glass Sintered Funnels have a porous filtering plate. They come in three sizes and two levels of porosity. Related Products: Sintered Glass Funnel. The 47mm holder is the standard size for microbiology and uses a 47mm filter membrane. Related Products: Vacuum Filtration Kit. It is also recommended for HPLC solvent filtration.
Complete set includes a borosilicate glass funnel, anodized aluminum spring clamp, vacuum base with sintered disc, and ground joint flask. Membrane filters are not included.
Switching from LEE to NiSi Filters: Was it a Mistake?
Filter diameter…. Related Products: Vacuum Filter Flask. Related Products: 47 Mm Filter Holder. Suitable for aqueous and organic solvent filtration. The funnel seal ensures that the sample does not bypass the membrane and that particulates are retained on the surface of the membrane.
The sintered …. Related Products: Vacuum Filter Holder. The No.Sometimes you hear words that sound like element names, like didymium, coroniumor dilithium. Yet, when you search the periodic table, you don't find these elements.
Didymium is a mixture of the rare earth elements praseodymium and neodymium and sometimes other rare earths. The term comes from the Greek word didumusmeaning twin, with the -ium ending.
The word sounds like an element name because at one time didymium was considered to be an element. In fact, it appears on Mendeleev's original periodic table.
Swedish chemistry Carl Mosander discovered didymium in from a sample of ceria cerite supplied by Jons Jakob Berzelius. Mosander believed didymium was an element, which is understandable because the rare earths were notoriously difficult to separate at that time. The element didymium had atomic number 95, the symbol Di, and an atomic weight based on the belief that the element was divalent.
Didymium was known to be responsible for a pink color in ceria salts. Per Teodor Cleve determined didymium must be made of at least two elements in InLecoq de Boisbaudran isolated samarium from a sample containing didymium, leaving Carl Auer von Welsbach to separate the two remaining elements in Welsbach named these two elements praseodidymium green didymium and neodidymium new didymium.
The "di" part of the names was dropped and these elements came to be known as praseodymium and neodymium. As the mineral was already in use for glassblower's goggles, the name didymium remains.
The chemical composition of didymium is not fixed, plus the mixture may contain other rare earths besides just praseodymium and neodymium.
In the United States, "didymium" is the material remaining after cerium is removed from the mineral monazite. While the ratio of neodymium and praseodymium varies, didymium usually contains about three times more neodymium than praseodymium. This is why element 60 is the one named neodymium. There are reports that didymium glass was used to transmit Morse Code messages across battlefields in World War I. Share Flipboard Email.
Anne Marie Helmenstine, Ph. Chemistry Expert. Helmenstine holds a Ph. She has taught science courses at the high school, college, and graduate levels. Facebook Facebook Twitter Twitter. Updated November 01, Today, didymium is not an element, but is instead a mixture of rare earth elements. These elements had not been separated from each other in Mendeleev's time. Didymium mainly consists of praseodymium and neodymium.
Didymium is used to color glass, make safety glasses that filter yellow light, prepare photographic filters that subtract orange light, and to manufacture catalysts. When added to glass, the right mixture of neodymium and praseodymium produces a glass that changes colors depending on the viewer's angle. Although you may have never heard of didymium, you may have encountered it:.
Didymium and its rare earth oxides are used to color glass. The glass is important for blacksmithing and glassblowing safety glasses. Unlike dark welder glasses, didymium glass selectively filters out yellow light, around nm, reducing the risk of Glassblower's cataract and other damage while preserving visibility. Didymium is also used in photographic filters as an optical band-stop filter.We purchase every product we review with our own funds — we never accept anything from product manufacturers.
Photographers love to shoot beautiful nature scenes that show blue sky, open water, and forested areas. And while these landscapes seem like an easy scene to shoot with no fast-moving subjects, it occasionally ends in disappointment. With bright sunlit photos that have a lot of sky in them, the photos sometimes end up washed out. One way to bring vibrancy back to this style of photo is with a polarized lens filter.
The polarizing filter alters the way the camera measures the light from the scene. The filter reduces the effects of glare and reflections, preventing hot spots and washed out areas. You must pick the right size of polarizing filter to fit your lens.
Best ND grad filters: 8 top models tested
The filter has threads that match the threads inside the edge of the lens. Manufacturers create specific filters to fit specific lenses. It has to match the diameter of the lens. Each lens should have its diameter marked in millimeters on the front end of the lens. The number usually will be signified with a circle and a diagonal or vertical line through it. Common sizes are 52mm or 67mm. Other cameras make use of a filter bracket. This attaches to the end of the lens and holds the polarizing filter in front of the lens glass.
Some photographers keep lens filters attached to the lens at all times. This protects the lens from scratches. Some photographers think of a polarizing filter like sunglasses for the camera.
All polarizing lens filters are round in shape, but you can purchase either a linear or a circular filter. This term refers to the way the filter works instead of the shape. The linear filter blocks glare better than the circular filter. The circular filter allows you to use the autofocus and auto exposure features of your camera. The linear filter inhibits the measurements the camera uses to set these automatic features, leaving them ineffective. When using a circular polarizing filter, you often can change the way the filter affects your photos by just twisting it a little bit inside the lens.
This alters the way the filter blocks the light, ensuring you can find the right level for each photo. Some polarizing filters have a color tint in them, which can result in incorrect colors in your photos.
Sintered Glass Filter
With certain lenses, a filter with a thick rim can cause vignetting in the image. This is the loss of color quality and image sharpness at the edges of the photo. Thinner rims on the polarizing filter are preferred to avoid vignetting, but these filters usually cost more. These filters will have wider rims, which may cause some problems with vignetting when used with a wide-angle lens. Additionally, they may not have high quality glass. However, they will work fine for everyday, amateur photography.
The majority of photographers can have an acceptable level of image quality with a mid-range polarized lens filter. Expect a good quality of glass in the filter and small thickness in the rim.
These filters will have very thin rims, outstanding glass, and excellent build quality. Only advanced amateur and professional photographers can take advantage of the quality of these high-priced filters. We also should mention that the polarized lens filters will have varying costs based on the diameter of the filter. Understand that using a polarizing lens filter blocks some of the light in the scene from entering the lens. Polarizing filters are not useful in every photographic situation.About one year ago I was contacted by a Chinese brand named NiSi and invited to test their products.
This is my experience with their filter system and filters one year later. The NiSi Filter System provides a positive impression straight out of the box. The filter holder is contained in a beautiful leather box, just like the filter pouch.
Still, it is worth mentioning that the presentation is beautiful and it looks exclusive right away. However, if it takes too much space you can just remove the holder and leave the box at home. Since the clips are so small I was afraid that the filter holder would fall off the adapter. Also, the NiSi Filter Holder has one of my all-time favorite features.
Either you need to screw the Polarizer on the lens and attach the holder outside, which usually results in vignetting. When I evaluate filters there are two main things I look for; colorcast and quality of the glass. This was my biggest worry in the beginning since, as I mentioned, I was already pleased with my current system. Worst of them all, despite being a great filter otherwise, is LEE Filters. I had used LEE Filters for years and had gotten used to the heavy blue color cast.
Even though I initially had no intent of switching from LEE. But I would consider it if I found the color cast to be significantly less and the quality of the glass to be no less. My biggest surprise when taking the first image with my new NiSi Stop ND Filter was that there was absolutely no color cast. I honestly had to rub my eyes a few times to make sure I saw it correctly.
No heavy blue color cast, no bright yellow. Another benefit of the NiSi filters is that the filters are of glass, not resin. This makes them more durable, harder to scratch and most importantly… easier to clean!
Again, the NiSi filters are glass, not resin, which makes them harder to scratch and damage.