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Sticky :: UV/Vis/IR Filters (You are here.)

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Best Basic Gear:  Goggles, Filters, Torches

Beginners might want to start with this topic. Then return here for more details.

 

Sticky :: UV/Vis/IR Filters

by Andrea G. Blum for UltravioletPhotography.com

[LAST UPDATE: 5 July 2024. Removing obsolete material.]

 

Note from Editor:

This Sticky began as a joint effort by the members of various forums who enjoy UV/IR photography. Thanks to everyone for their suggestions, comments, proofreading, lists, links, measurements, experiments and all round good fellowship.

 

Please PM Andrea B. on UltravioletPhotography.com with any corrections, additions or suggestions. Or write to rudbeckia at ultravioletphotography dot com.

 

Abbreviations:

  • IR = infrared
  • UV = ultraviolet
  • UV/IR = ultraviolet and/or infrared

[ultravioletPhotography.com does not endorse any specific products as a website. We simply offer reports, reviews and gear lists for your further investigation. Any opinions in such reports/reviews/lists belong solely to the poster writing them. UltravioletPhotography.com as a website receives no compensation or income from any source.]

 

 

CONTENTS

 

UV/IR FILTERS Introduction

  • Filter Care
  • Shooting with Shiny-sided or Dichroic Filters

FILTERS and GLASS: IR-PASS

  • Filters: IR-Pass
  • Filter Glass: IR-Pass

FILTERS and GLASS: UV-PASS

  • IR Leakage in Some UV-Pass Filters
  • Filters: UV-Pass with Minor or No IR-leakage
  • Filters: UV-Pass with Unknown IR-leakage
  • Filters: UV-Pass with Major IR-leakage (Dual Bandpass)
  • Filter Glass: UV-Pass
  • Filter Stacks: UV-Pass + IR-Block

FILTERS and GLASS: IR-BLOCK

  • Filters: IR-Block
  • Filter Glass: IR-Block

FILTERS: UV/IR-BLOCK (Visible Pass)

 

 

 

UV/IR FILTERS

Introduction

 

When referencing filter transmission and blocking ranges, the reasonable assumption is made that Visible light covers the range 400-700 nm, Ultraviolet light is the range 300-400 nm, and Infrared light has a 700-1100 nm range. These divisions cover the approximate range of a converted digital camera sensor.

 

The filters listed here are all pre-mounted and circular. Non-circular filters can of course be used in appropriate adapters and links to any such filters are welcomed. We have tried to give both a manufacturer's link for each filter brand and link to a transmission chart. Because Hoya or Schott glass is a reference standard and used in the manufacture of many filters, it is also discussed.

 

Please Note: Stated transmission ranges are approximate as charts may be difficult to read or not precisely accurate. Also, a manufacturer's transmission chart may be for a thickness standard that is not necessarily the thickness used by a finished filter supplier. Less reputable finished filter suppliers may provide a manufacturer's chart that is not valid for the thickness of their supplied filter.

 

Filter Care

 

Clean your filters carefully after use and before storage. Blow off any dust and particles with a bulb blower. Use a cleaning fluid that is made for use on coated filters. Clean and dry with a microfiber cloth or lens tissue because some coatings or special glasses are easily scratched.

 

Dust, pollen, perspiration and contact with stronger acids or alkalines can damage filters. Some filters may deteriorate over time from solarization effects due to overexposure to Ultraviolet light. Chemical changes such as oxidation of the glass or of the coatings can also occur especially on uncoated filter glass. And fungus can attack filter glass or filter coatings just as it attacks lenses.

 

If a filter becomes filmy or sticky or develops small crystals, clean it immediately to preserve it for future use. Oxidation on uncoated or unclad filters can be delayed by storing filters with dessicant packs. Using hydrogen peroxide or a fine-grade cerium oxide glass polish can remove light oxidation. Regular cleaning will prolong the life of all filters. Store filters as you would store your lenses - in a warm, dry place.

 

See more about filter care in the later section Filter Stacks: UV-Pass + IR-Block.

 

Shooting with Shiny-sided or Dichroic Filters

 

One problem with hard-coated, shiny-sided filters is that they can sometimes induce reflections and flare within the lens barrel and/or camera chamber from any entering light, but most particularly from off-axis light. The reflections can cause a general lack of contrast or create interesting annular patterns in the photo in addition to the typical aperture-shaped light blobs along a diagonal.

 

Ideally with such shiny filters, the photographer remembers not to shoot contra jour. Move yourself or your photographic subject to prevent backlighting. Turning the shiny filter side outward to face the photographic subject, using a lens hood and rear mounting a small version of the filter all help mitigate potential reflection and flare problems. With a filter like the UV-pass BaaderU, just as one example, 98 times out of 100, you won't see any problem from its shiny side. But some hard-coated (industrial) filters with two very shiny mirrored surfaces cannot be adapted for general outdoor UV photography and are extremely difficult to use in the studio as well. Informal observations indicate that transmission of the desired wavelengths is not affected by which direction the shiny side of a filter is facing.

 

A dichroic filter also can create some concentric discoloration on the edges of a photo. It is often observed when the dichroic filter is used over a wide-angle lens but may also occur with longer focal lengths. Dichroic discoloration in a long focal length photo can be easily cropped away. In either a narrow-angle or a wide-angle photo, such discoloration can often be mitigated by a suitable monochrome or split-tone conversion and use of vignetting tools. An example can be found in one of the SEU Gen2 filter tests: Monochrome Conversions of Dichroically Discolored Photos

 

 

 

FILTERS and GLASS: IR-PASS

 

Note that "red leak" mentioned below in conjunction with IR-Pass filters is not a bad thing. Many IR photographers want a bit of red leak in their IR photos because it can be manipulated to give pleasing IR false colour by red/blue channel swapping or other processing techniques.

 

Filters: IR-Pass

Listing order is alphabetical by company. Order does not imply preference.

 

(1) Baader-Planetarium IR-Pass Filter #2458386

The Baader-IR transmits above 685nm, passes high red + IR and has some IR false colour capability. Transmission chart is not currently available. Baader filters may be found at many astrophotography and astronomy retail/online shops as well as at Baader-Planetarium.

(2) B+W 099, 092, 093 IR-Pass Filters

B+W 099 passes orange, red & IR, reaches 50% transmission at 550nm, has IR false colour capability.

B+W 092 ("dunkelrot") passes high red & IR, reaches 50% transmission at 695nm, has some IR false colour capability.

B+W 093 ("schwarzrot") passes IR only, reaches 50% transmission at about 830nm.

(3) Heliopan RG Series IR-Pass Filters

Heliopan IR-Pass filters are made with a Schott glass substrate.RG645/665/695/715 pass IR & red (in varying amounts) and have some IR false colour capability. RG780/830/850/1000 pass only IR.

(4) Hoya R Series, RM Series IR-Pass Filters

Hoya IR-Pass filters are made with a Hoya glass substrate, of course.R-70, R-72 pass high red & IR, reach 80% transmission at approx. 745/765nm and have some IR false colour capability. RM-90, RM-100 pass IR only and reach 80% transmission at approx. 1050/1200nm.The IR transmission cut-ins begin at 700/720/900/1000nm, respectively.These are the pre-mounted, circular filters which are commonly available.See the Hoya glass entry below for more information.

(5) LifePixel IR-Pass Filters for Internal Conversion of Camera

LifePixel is a retail camera conversion shop. There are five internal IR-pass filters used in their conversions: Deep BW (50% at ~825nm), Standard (~710nm), Enhanced Color (~665nm), Super Color (~600nm) and Super Blue (~275-460nm in UV/violet/blue and ~710+ in IR).

  • LifePixel Home page.
  • LifePixel IR-Pass Filters Transmission charts.On this FAQ page, scroll down to the question"What kind of filters do you use for conversions?" and click it to see charts.

(6) MaxMax X-Nite Series IR-Pass Filters

R + IR: X-Nite 630/665/715 with some IR false colour capability. X-Nite 780/830/850/1000 pass IR only. (These look like Schott glass numbers?)

(7) MaxMax BP Color Series IR-Bandpass Filters

This set of 3 IR-bandpass filters might enable an interesting RGB channel mapping from the IR band. Note that the shiny metallic surface of these filters indicates that they are dichroic. With a dichroic filter, transmission varies with incidence angle and can lead to variable wavelength performance across the filter, especially for wide angle lenses. Longer wavelength IR is more affected by this.

(8) Peca 900 Series IR-Pass Filters These filters are sold in a 62mm mount size. Peca 902/914 pass high red & IR and have some IR false colour capability. Peca 908 passes some violet/blue/UV below 450nm, but has no red or near-IR leak. Peca 904/906/910 pass IR only. Peca 912 is a wideband IR-pass between appox. 700-1200nm.

(9) Singh-Ray I-Ray IR-Pass FilterThis filter is advertised to transmit 90% of near-IR light between 700-1000nm. No transmission chart is currently available.

(10) Tiffen 87 IR-Pass Filter The filter transmits above 725nm, so is IR-pass only.

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Filter Glass: IR-Pass

Listing order is alphabetical by company. Order does not imply preference.

 

(1) Hoya R, IR, RM, RT Series IR-Pass Filter Glass

Hoya Candeo is a Japanese manufacturer of optical products including filter glass and pre-mounted, circular filters. Their glass is used by many photographic filter manufacturers. In addition to the R and RM series glass used in Hoya mounted filters listed above, the chart shows IR 76N, 80N, 83N and 85N glass with IR transmission cut-ins beginning at 760/800/830/850nm, respectively, and having a 60nm interval prior to reaching peak transmission (not given).

(2) Schott RG Series IR-Pass Filter Glass

Schott AG is a German manufacturer of optical products (and other products). Their glass is used by many photographic filter manufacturers. The Schott "RG" prefix denotes IR transmitting glass. The number indicates the wavelength where 50% IR transmission is reached.

R + IR: RG 9/610/630/645/665/695/715 with some IR false colour capability.

IR Only: RG 830/850/1000.

 

 

FILTERS and GLASS: UV-PASS

Editor's Note: I have decided to be out of the business of judging how much IR leakage any of these UV-Pass filters have. Learn how IR leakage can contaminate a UV photograph and be sure to examine the transmission charts for any filter you buy.

 

Dual Bandpass of UV+IR in Some Old UV Filters and in Filter Glass

The filter glass substrates used to make UV-pass filters are dual bandpass with significant transmission in the IR range. (Reference below Filter Glass: UV-Pass.) To create an UV-pass only filter, dichroic coatings, hard coatings or ionic layers are added to the filter glass to block IR. We recommend that you look for IR-blocking between at least OD3.5-OD4.0, (more is better), for use in digital UV photography.

 

Some older UV-pass filters created for use in astronomy or for use with UV-film do not reach the OD3.5 level of IR blocking because that was not needed when using IR-insensitive UV-film. For example, the old BaaderU, the ScheulerU or the B+W 403 will not work well for digital UV photography due to IR contamination. To use one of those dual-bandpass filters successfully for digital UV photography, you must stack it with an IR-blocker made from some type of blue-green glass such as the Schott 8612. (Reference below Filter Glass: IR-Block.)

 

Dichroic, hard-coated UV-pass filters or commercial ionic UV-pass filters are typically quite expensive. A less expensive approach to UV-pass filtration is achieved by stacking one of the Hoya or Schott dual-bandpass (UV+IR) filters together with a IR-blocker made from some kind of BG glass. This do-it-yourself stacking saves some money, but you must remember to frequently check your uncoated filter stacks for possible oxidation. It is mentioned above in Filter Care that hydrogen peroxide baths or fine-grained glass polish can remove early signs of oxidation.

 

 

Filters: UV-Pass with Minor or No IR-leakage

Listing order is alphabetical by company. Order does not imply preference.

 

(1) Baader-Planetarium BaaderU UV-Pass Filter #2458291 350FWHM60

This absorptive/dichroic UV-Pass filter transmits 78% at its peak of 350 nm. Its half-maximum range of greater than 39% transmission is between 320-380 nm. The BaaderU has a Schott UG11 absorptive substrate with dichroic (interference) coatings. The filter was developed for astronomy and may be found at many astrophotography and astronomy retail/online shops as well as at Baader-Planetarium. It is available mounted in 2" and 1.25" sizes.

 

Prior to photographic use, it is recommended that the BaaderU be reversed in its mounting ring so that the pink side faces the subject, not the sensor. When the pink side faces the sensor there can be increased internal flare off its highly reflective surface. The orientation of the filter does not seem otherwise affect the UV image although the pink side is supposedly more IR-reflective.

 

With a dichroic filter, transmission varies with incidence angle and can lead to variable wavelength performance across the filter, especially for wide angle lenses. Be sure to read above: Shooting with Shiny-sided or Dichroic Filters. A conversion suggestion for wide-angle dichroic discoloration is mentioned there.

 

Editor's Note: I have seen some vignetting with the BU on some lenses because of its 2" size. This might be cured with different step-rings or rear mounting.

 

(2) Kolari Vision UV Bandpass Filter 365FWHM40

This absorptive/dichroic UV-pass filter transmits 50% at its peak of 365 nm. Its half maximum range of >25% transmission is between 340-380nm. The minimum OOB rejection is 3.5O OD with an average of 4.3 OD. Substrate info is not provided. On a wide-angle lens the KU will not have the peripheral colour banding sometimes seen with filters having dichroic coatings.

 

Filters: UV-Pass with Unknown IR-leakage

 

I'm going to list here a new UV-Pass filter which has not been tested by any of our members but for which the specifications look good.

 

(1) Astrodon UVenus UV-Pass Filter

Astrodon has discontinued their Astrodon-Schuler UV-Pass filter. They are now offering a hard-coated UVenus filter which has an average UV transmission of about 90% between 325-381 nm. The filter has a fused silica substrate. The non-UV leakage is given as less than .1% between 420-1100nm, but we have not yet had anyone test this filter for photographic use. It is available in a 1.25" mounted size and a 49.7mm unmounted size.

.

 

Filters: UV-Pass with Major IR-leakage (Dual Bandpass)

 

Listing order is alphabetical by company. Order does not imply preference.

 

RECOMMENDATION: You must stack an IR blocker over these filters for use on a digital camera. See "IR Leakage in Some UV-Pass Filters" above.

 

(1) B+W UV Black 403 UV-Pass Filter

This dual bandpass filter transmits 320-385nm (50% bandwidth) with a large IR bump around 740nm (approx 50% transmission). Most visible light is blocked although there is still a 10% toe at 400nm, so a bit of violet/blue is leaked. The 403 must be used with an IR-block filter to prevent IR contamination of a UV photograph. This filter has a UG1 substrate. Note that some of the English translations are incomplete in the following links.

(2) MaxMax X-Nite 330 UV-Pass Filter

This filter transmits up to 78% UV between 240-400nm with a peak at 330nm and a 10% IR leak around 720nm. MaxMax recommends that it be used with their X-Nite BP1 filter to prevent IR contamination of a UV photograph. This will affect UV transmission below 300nm in case you have a lens that can transmit UV that low.

(3) Peca 900 UV-Pass Filter

This filter transmits approximately 250-400nm with a 25% IR bump around 715nm. It must be used with an IR-Block filter to prevent IR contamination of a UV photograph. (A Peca UV-Pass 901 is listed but the link is broken for its transmission chart.)

.

 

Filter Glass: UV-Pass

Listing order is alphabetical by company. Order does not imply preference.

 

It is important to briefly discuss the types of glass commonly used as substrates in UV-pass filters to better understand their construction and characteristics. View the linked transmission charts directly for the most accurate analysis of each type of glass.

 

(1) Hoya U Series UV-Pass Filter Glass

Hoya Candeo is a Japanese manufacturer of optical products including filter glass and pre-mounted, circular filters. Their glass is used by many photographic filter manufacturers. The number indicates the peak UV wavelength of each filter.Currently only U-330/340/360 are listed by Hoya. The U-325C and U-350 seem to no longer be produced.Uncoated or unclad glass may be prone to oxidation. Store U-glass with a dessicant and regularly polish it with a cerium oxide glass cleaner.

  • U-330 Maximum UV transmission of approx. 85% for 2.5mm thickness between 230-400nm.Leaks small amount (less than 10%) of violet/blue between 400-420nm.Big IR leak beginning at about 650nm, peaking at 50% around 720nm.
  • U-340 Maximum UV transmission of approx. 78% for 2.5mm thickness between 260-400nm.Leaks IR between 680-740nm, peaking at 3% around 720nm.WARNING: There is yellow-green visible leakage from thin versions of U-340 filter glass. For example, at a 1.0mm thickness you can easily see the U-340 greenish leak. Go thick when purchasing U-340 glass for use in UV-pass work.
  • U-360 Maximum UV transmission of approx. 72% for 2.5mm thickness between 290-400nm.Leaks IR between 700-800nm, peaking at 10% around 740nm.

(2) Schott UG Series UV-Pass Filter Glass

Schott AG is a German manufacturer of optical products (and other products). Their glass is used by many photographic filter manufacturers. The Schott "UG" prefix denotes UV transmitting glass.Uncoated or unclad glass may be prone to oxidation. Store UG-glass with a dessicant and regularly polish it with a cerium oxide glass cleaner or give it an overnight H2O2 bath.

  • UG1At 1mm thickness, this glass transmits about 80% UV (at peak) between 275-425nm,passes some violet/blue between 400-425nm,is flat between 425-675nm in the Visible range,passes some red between 675-700nm, andpasses large amounts of IR (50% at peak, 5% minimum) from 700nm onwards.
  • UG2A Info to be added.
  • UG5At 1mm thickness, this glass transmits the most UV, up to 98%, between 225-400nm,passes varying amounts in the Visible range (50% or more at max and 1% at min),passes large amounts of IR (70-80%) starting at 700nm.
  • UG11At 1mm thickness, this glass transmits up to 92% UV between 235-410nm,passes only a tiny amount of violet/blue,is flat between approx. 400-650nm in the Visible range,passes some red (1-20%) between 675-700nm, andpasses moderate amounts of IR (1-20%) starting at 700nm.

(3) Chinese ZWB Series UV-Pass Filter Glass

Warning: Unfortunately we cannot at this time wholeheartedly recommend inexpensive ZBW UV-pass filter glass sold on Ebay because of problems with excessive striations, pits and other flaws reported by members. There also seems to be some problems with Visible leakage. (Please remember that the occasional little bubble in good filter glass or lens glass is not considered a problem.)

Update: 24 August 2021. There seems to have been some improvement in the ZBW manufacturing. Some members are reporting that their ZWB filters perform well. There are still reports of excessive striations or other flaws along with refusals by the sellers to refund money. Check the forum posts to see latest discussions about ZWB filter glass.

 

(4) Other Filter Glass Manufacturers: Kopp Glass, Newport Industrial Glass

There are a lot of other optical glass manufacturers besides Hoya and Scnott. Here are two which we know about because we like their glass equivalencies charts.

.

Filter Stacks: UV-Pass + IR-Block

Manufactured, coated UV-pass filters are usually expensive. It is possible to save a bit by making a DIY stack of mounted UV-pass glass together with some type of mounted blue-green IR-blocking glass. Currently the preferred choice for IR-blocking is Schott S8612, if you can find it. If not then look for Schott BG glass. There are some possible drawbacks to stacked filters which you should be aware of.

  • Chemical changes such as oxidation can occur on uncoated glass. Oxidation can be delayed or prevented by storing stacked filters with dessicant packs. An overnight hydrogen peroxide bath or a cerium oxide glass polish can remove light oxidation. Regular cleaning will prolong the life of stacked filters.
  • A filter stack can induce flare. If it should occur, try a lens hood and don't shoot into the light.
  • A filter stack may have reduced transmission of desired wavelengths. There will be more layers of glass and some air between the filters.
  • A filter stack may require longer exposure times. As a consequence of the preceding point, a UV flash may be necessary. But then, a UV flash is almost always useful in UV photography with any filter.
  • The UV-pass glass and IR-block glass much be carefully matched to suppress IR leakage. Study the glass transmission charts carefully to match up the IR-leaky ranges in your choice of UV-pass glass with an IR-block glass which suppresses that range - but which may very well leak elsewhere.
  • IR leakage cannot always be fully suppressed without coatings. Even the best manufactured UV-pass filters may leak tiny amounts of IR, so the goal is to reduce IR-leak by enough that its effects are negligible on the UV photo. This goal can be aided by choosing thick enough IR-blocking glass which is yet not so thick that exposure times become painful.
  • A filter stack can cause loss of fine detail. I'm not sure what causes it specifically, but this can look like faint fog on or around fine details.

Here are some filter stack experiments I made with some known IR-leaky UV-pass filters. The results were good.

 

 

FILTERS and GLASS: IR-BLOCK

IR-block filters find use in multi-spectral photography, are used as hot mirrors or are needed as IR suppressors when stacked with IR-leaking UV or Visible filters of various types. Many of the older manufactured IR-block filters are not so great at supressing all the IR. However, recently Schott has developed some new and better IR-block glass for use as an internal hot mirror in digital equipment. Ideally we shall soon see some manufactured filters made with this.

 

Filters: IR-Block

Some of the manufactured IR-block filters listed here do a rather poor job of completely suppressing the IR. The benefit of listing them here anyway is that you can avoid buying them if it is pure IR-blocking which you need. They may still be useful in filter stacks if their IR suppression interval matches another filter's IR leaking interval.

 

(1) B+W 489 IR-Block Filter

This filter, having a KG3 substrate, has a gradual slope between 700-780nm, so it transmits approximately 50% IR at 700nm. It is not recommended as an IR-block for use in UV work.

  • Schneider Kreuznach Home page of parent company. (In German)
  • B+W Photo Filters General information.
  • B+W Filter Types
  • [/b] [/i]Home page of U.S. subsidiary of Schneider Kreuznach.
  • B+W Filter Handbook PDF. B+W 489 is on page 27. Transmission chart is on page 61.

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(2) Kenko DR655 Deep-Red Cut IR-Block Filter

This filter transmits from 350-700nm with a very steep slope between 650-700nm, so cuts IR very effectively. It cuts violet/blue by half between 400-450nm. Between 450-650nm the chart is bumpy. This is an interference (dichroic) type filter.

(3) MaxMax X-Nite CC1, X-Nite CC2, X-Nite BP1 Color Correction or IR-Block Filters

The CC1, centered at 483nm, transmits between 310-700nm reaching below 5% transmission at 700nm and mostly suppressing the 700-900nm range. After 900nm, IR leakage climbs again. The CC1 might work well as an adjunct when stacked with some IR-leaky UV-Pass filters if the transmission charts match up.The CC2, centered at 500nm, allows significant IR leakage, transmitting between 70-40% IR between 700-800nm.The CC1 and CC2 filters are meant to be used on cameras whose Visible colour is altered by removal of the internal IR blocking filter. However, the CC2 looks a little dicey to me.The BP1 transmits between 350-700nm with a sharp right-hand slope down to 10% at about 660nm. Between 700-800nm IR leakage appears to be below 2.5%. After 800nm, IR leakage rises again. However, the BP1 works fairly well as an adjunct when stacked with the MaxMax XNite 330C UV-Pass filter.

.

(4) Tiffen Standard Hot Mirror IR-Block Filter

Transmits 380-700nm then slopes down to about 780nm, so leaks some UV and leaks some IR with additional bumps past 780nm. No transmission chart is available from the manufacturer. We do not recommend this for use on a broadband converted camera.

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Filter Glass: IR-Block

Listing order is alphabetical by company. Order does not imply preference.

 

(1) Schott BG Series, S Series, VG Series IR-Block Filter Glass

Schott AG is a German manufacturer of optical products (and many other things). Their glass is used by many photographic filter manufacturers. The Schott "BG" prefix denotes blue or blue-green glass, and "VG" denotes green glass.There are many Schott IR-block glass types not mentioned here. I've tried to choose the glass most often found as a substrate in manufactured filters. And I've listed some of the newer IR-supressing Schott glass - the newest version being VG20.

The older Schott IR-block glass is labeled BG 38/39/40/42. It transmits both UV and Visible wavelengths between approximately 300-700nm. The right shoulders of the transmission curves vary in their slopes and cutoff points.At the 700nm mark BG 39/42 in 1mm thickness are the best IR supressors at a .01% level with BG39 transmitting slightly more Visible light.

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The newer Schott IR-block glass is labeled BG 60/61/62/63/64. It differs from the older versions above by the addition of a protective coating against corrosion. The glass transmits both UV and Visible wavelengths between approximately 300-700nm. The right shoulders of the transmission curves vary in their slopes and cutoff points.At the 700nm mark BG 60/61/62 in 1mm thickness are the best IR suppressors at a .01% of lower level with BG61 transmitting slightly more Visible light.

.

A very good Schott IR-blocking glass is S8612. At the 700nm mark the IR supression is at a .01% level for a 1mm thickness. S8612 has a high UV and Visible transmission at a peak of 98%. Currently S8612 is the preferred choice for IR-blocking here on UVP.

The newest Schott IR-block glass is VG20, a green glass. At the 700nm mark the IR suppression is already at the 1E-04% level for a 1mm thickness.

  • Schott VG20 PDF. Data sheet with transmission charts.

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(2) Hoya C Series Color Compensating Filters

Hoya Candeo is a Japanese manufacturer of optical products including filter glass and pre-mounted, circular filters. Their glass is used by many photographic filter manufacturers.The C Series glass is manufactured for use in digital devices to suppress IR contamination. The C types - C500S, E-CM500S, C5000, CM5000, CD5000 - all have similar transmission between 310-700nm reaching about 85-90% transmission of visible light between 400-550nm, then dropping to about 50% transmission between 600-620nm. The E-CM500S, with about 3% transmission at 700nm, appears to be the best at suppressing IR between 700-1100nm.

 

 

FILTERS: UV/IR-BLOCK (Visible Pass)

Listing order is alphabetical by company. Order does not imply preference.

 

Just call them Visible bandpass filters. They are necessary if you want to use a full spectrum camera for Visible light shots or for UV-induced fluorescence in the Visible range. Small leakage on the UV side is not as troublesome to a Visible photo as IR leakage can be. Here is a good reference: UV/IR-Block & IR-Block Filters on a Converted Camera. {Add URL.} As stated there, the bottom line is that for accurate converted-camera visible colour under a UV/IR-block filter you must:

  • pre-measure white balance in-camera against a white/grey card, and
  • make a converter colour profile for your particular camera+lens+filter combination.

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(1) Baader-Planetarium UV/IR-Cut Filter 2" #2459210A = Version A

This filter transmits 410-680nm with the only IR bump way out there past 1200nm. Very minor UV leakage. It is considered one of the best UV/IR blocking filters. Cuts some blue between 400-410nm. Baader filters may be found at many astrophotography and astronomy retail/online shops as well as at Baader-Planetarium.

ADDED 23 May 2023:  The Baader UV/IR-Cut filter stacked with Schott BG 38 provides a slightly better color rendition by tapering the left (violet-blue) and right (red) shoulders. Some magentas, pinks and blue tones look better with this stack.

 

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(2) Astronomik UV/IR-Block Filter

This is a filter made primarily for astronomical use. It transmits quite a lot of UV, so it would not be suitable as a UV/IR block filter when making UV-induced Visible fluorescence photos. It appears to block IR quite well.

.

(3) B+W 486 UV/IR-Block Filter

This is an interference (dichroic) type filter. It has a 10% transmission toe at 700nm. Its left-hand shoulder transmits some UV between 360-400nm so it may not be suitable for UV-induced Visible fluorescence work.

.

(4) Heliopan Digitalfilter #8025 UV/IR-Block Filter

The filter transmits 325-710nm, so seems to allow UV and leak a little IR. It is probably not suitable for UV-induced Visible fluorescence work.

.

(5) Marumi UV-IR Cut UV/IR-Block Filter

This filter transmits 400-700nm with a very, very sharp slope between 380-400nm and 675-710nm. There is the tiniest IR bump at 750nm and larger IR bump way out past 1075nm.

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(6) Peca 700, 916, 918 UV/IR-Block Filters

Peca offers three UV/IR blockers. Each transmits 400-700nm, but varies in how the near-IR and near-UV is handled. Evaluate the charts carefully to determine whether you will get the needed UV/IR suppression for your particular use.

  • Peca Home page.
  • Peca IR-UV Filters List.
  • Peca 700 Transmission Chart
    The 700 filter reaches an 80% transmission of UV between 360-400nm. It transmits 80-90% IR between 700-725nm and leaks varying amounts of IR past 775nm with about 2.5% peaks. It must be stacked with IR-blocking glass.
  • Peca 916 Transmission Chart
    The 916 cuts UV well but again it leaks 80-90% IR between 700-725nm and leaks varying amounts of IR past 775nm with about 2.5% peaks. So it must be stacked with IR-blocking glass.
  • Peca 918 Transmission ChartThe 918 filter cuts some red in the 650-700nm range with about a 2% leak at 700nm and a minor bump around 850nm. It has minor UV leakage between 375-400nm.
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