Hoya Red Intensifier Review: An Affordable Light Pollution Filter for Astrophotography

Hoya Intensifier: An Affordable Light Pollution Filter

I don’t typically use filters for the type of astrophotography you see on Lonely Speck. Filtering for specific wavelengths of light is a common practice for astronomy and deep sky imaging. But most filters made specifically for astrophotography tend to be very specialized and very expensive. Luckily, there’s an option for those on a tight budget: the Hoya (Red) Intensifier Filter. In this short review, we test out the Hoya Intensifier while shooting the Milky Way from Trona Pinnacles, California.


Before trying the Hoya Intensifier, I had never used a filter for astrophotography. Other than the SharpStar2 for achieving precise focus on the stars, I didn’t know of an immediate reason to use a filter while shooting basic night photography.

Many dedicated astronomy filters are made to filter out everything but a very narrow band of light, specifically for targeting certain parts of the spectrum, like infrared or Hydrogen Alpha. These narrow band filters are usually best reserved for shooting on a full-spectrum camera or dedicated astronomy sensor. Other more common photographic filters like a UV filter, polarizer or neutral density filters don’t really provide any tangible benefits for astrophotography.

The Hoya Red Intensifier

The Hoya Red Intensifier (also just called the plain “Intensifier”) is a special application filter that’s intended to enhance red and orange colors, particularly for autumn foliage.

The Hoya Red Intensfier is also known as a Didymium filter. It filters out the yellow-orange portion of the spectrum from about 575nm to 600nm. The original application for a Didymium filter is to protect the vision of glassworkers from the bright yellow-orange color of the hot sodium in the glass. As I originally learned from Nick at Noctilove, this type of glass should make a good light pollution filter.


The Hoya Intensifier filters out yellow-orange light from about 575nm to 600nm (via hoyafilter.com).

 The part of the spectrum that the Didymium filter removes is also the exact color of most sodium vapor lamps, one of the most common sources of light pollution. Many city and suburban street lamps and industrial lighting use these yellow-orange lights. They’re slowly being replaced with LEDs in major cities, but sodium lamps are still one of the most common types of outdoor lighting. Being able to filter out most of this type of light should provides a distinct benefit for astrophotography.

Hoya Intensifier Filter for Astrophotography

At first glance, the Hoya Red Intensifier filter looks like a pretty plain filter. It’s a relatively clear looking filter but with a very subtle pink tint.

As far as I can tell, it appears that this filter does not have any anti-reflective coating as reflections off the surface of the filter glass appear to have no colored tint. A lack of coatings shouldn’t really affect most astrophotography but photographers should be aware when using it in other situations; it may cause unwanted reflections, particularly when shooting with very bright light sources in the frame.

Other than that, there’s nothing else to say about the appearance of the filter. It’s a pretty standard looking thing and comes in most common filter thread sizes from 49mm to 77mm.

Testing the Hoya Red Intensifier for Astrophotography

To test the Hoya Intensifier, I traveled with my girlfriend to Trona Pinnacles, California. It’s one of my favorite spots for astrophotography and is the site of our upcoming Lonely Speck Meetup 2016. Trona Pinnacles is a relatively dark sky location but there are still a few distict light pollution sources in the area: Ridgecrest to the west, Trona to the north, and Barstow to the South. Each of these towns create a mild orange glow visible in astrophotos.


Our test was made on a Sony a7S and two different lenses: the Voigtlander 21mm f/1.8 Ultron and the Sony Zeiss FE 55mm f/1.8 Sonnar T*. Each lens was fitted with a Hoya Red Intensifier for its respective filter size (58mm for the Voigtlander and 49mm for the Sony Zeiss).

Test shots were made in pairs: One set of shots was made with the filter removed and another identical set was made with the filter installed. The camera was set with identical settings for each set of shots. All photos were made with daylight white balance, manual exposure and manual focus. Let’s take a look at a first test shot:

Drag the center slider to see the result without (before) and with (after) the Hoya Red Intensifier filter.


This first test shot was made on the Voigtlander 21mm f/1.8 Ultron wide angle lens. The partially illuminated moon was still visible so the sky was naturally blue. As you can see, the filter noticably reduces the yellow glow created by the sodium vapor lamps of the mineral mining plant in Trona, California. The sky is darker and deeper blue and less hazy with the filter installed. Overall contrast is increased and you can see that the scene is slightly darker, likely since a portion of the ambient light spilling on the landscape is from the light pollution of Trona.

So far so good. The results were immediately noticeable, the filter seems to be doing its job of filtering out some light pollution.

Let’s take a look at another test image, this time of the Milky Way Galactic center, made after I had waited for the moon to set below the horizon.


This second test shot above was made with the Sony Zeiss FE 55mm f/1.8 Sonnar T*. Each image was made with the camera set to daylight white balance and by stacking 30 exposures to reduce noise. Images are normalized for brightness but post processing is otherwise identical between test images.

And below is a comparison of completely unedited images (exported straight from RAW) that should give you a good idea of the difference the Hoya Red Intensifier can make:


hoya-intensifier-light-pollution-filter-before-after-2 hoya-intensifier-light-pollution-filter-before-after-1[/twentytwenty]

If you’d like to see these as straight-out-of-camera RAW files, check out the download link to a zip of 3 before and after pairs of shots shot using the Hoya Red Intensifier. The files included in the .zip below are unedited and exported directly to DNG.

Want to see some RAW before/after files?
Download a .zip of RAW files (65.9MB)

The advantages of the filter become a lot more apparent when shooting the galactic center. The Hoya Red Intensifier seems to have almost completely neutralized the yellow/amber hues caused by the distant town of Barstow. The image with the filter installed shows more variety in color, especially when it comes to the blue, red and orange nebula of Rho Ophiuchi around the star Antares. The photo without the filter still looks acceptable but editing the shot to include a good balance of color would be a lot more difficult to achieve due to the orange tint. Overall, the filter really seems to have made a positive difference in the results and I’m super happy with how pronounced the faint colors are when they aren’t drowned out by light pollution.

What about in heavily light-polluted areas?

In the comments below, Anthony Roggio asks: “Any shots with this filter in a heavily light-polluted setting? Somewhere near a major city maybe?”

I shot the following sample of the constellation Orion in Simi Valley California, near Los Angeles. It’s a pretty heavily light polluted area and the photos from the location initially had a lot of amber tint to them.
[twentytwenty] hoya-intensifier-suburban-light-pollution-beforehoya-intensifier-suburban-light-pollution-after[/twentytwenty]

The light pollution filter seems to have completely neutralized the amber tint. I still think that the light from Los Angeles was too intense to really start to get some of the faintest nebula detail from the constellation Orion, but it’s neat to see how the filter removes the amber glow.

More Samples Made with the Hoya Red Intensifier Filter

I continued to shoot for the rest of the night with the Red Intensifier filter installed. Overall I’m very happy with how much staturation is apparent across the sky. Nebula are colorful, airglow (the green glow) is saturated and the bright light pollution on the horizon seemed greatly diminished from what I am typically familiar with at Trona Pinnacles. Here are a few more examples made with the filter installed:





Conclusions and Verdict

The results of using the Hoya Red Intensifier on the night sky is subtle but tangible. I very much prefer the results with the filter installed. I never thought I’d find myself thinking a filter as being essential for astrophotography but I think I’m going to keep using one on all my lenses. It’s cheap, it reduces light pollution, it works. Highly Recommended!

Hoya Red Intensifier Pros:

  • Greatly reduces the effect of light pollution, neutralizes yellow tinge from Sodium lamps
  • Affordable
  • Available in most common filter thread sizes (49mm-77mm)

Hoya Red Intensifier Cons:

  • Does not appear to have any anti-reflective coating
  • No square version available for filter systems
  • Reduces some light transmission

Hoya Red Intensifier Verdict:
Highly Recommended! (4.8/5)

Lonely Speck PureNight

We saw some of the shortcomings of the Hoya Intensifier and the requests by many photographers for a square version of the filter so we’re trying to make our own intensifier called the PureNight. PureNight will be multi-coated for better anti-reflective properties and our first run will be available in square 85mm and 100mm sizes. PureNight is available for pre-order now. 

Lonely Speck PureNight Light Pollution Reduction Filter




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89 Responses

  1. rick colman September 26, 2017 / 10:33 am

    Would resuilts be similar for a “converted camera” that passes H-alpha as well as visible?

  2. Dustin C Mills August 26, 2017 / 4:16 pm

    Would the Haida Clear-Night NanoPro 77mm filter be comparable?

  3. Kellye June 25, 2017 / 3:19 pm

    Has anyone ever tried this filter for fireworks?

  4. Eric Watson May 2, 2017 / 11:03 pm

    can you put a clear MRC nano coating filter in front of the Hoya filter to cut out glare and ghosting? B+W makes a clear 007 MRC nano filter.

  5. Olivier March 28, 2017 / 5:39 am

    Hi Ian,
    Here, in France, Tiffen filters aren’t available. Hoya Red Intensifier seems to end at 77mm and I need a 82mm to fit to my Canon 16-35 f/2.8. B&H charges too much for shipping to France.
    I’ve find a Kenko 82mm Red Enhancer (https://www.amazon.com/Kenko-82mm-Enhancer-Camera-Filters/dp/B0001DQJZQ). Is it similar ?
    Thanks for your reply

  6. R. Hipwell. March 13, 2017 / 12:24 pm

    Just a note about your opening description of the ” Hoya red intensifier”

    I find myself annoyed and greatly disappointed after wasting £66.00 on one of these after reading this article.

    I found out that it is NOT, that is NOT, a true Didymium filter.

    How did I find this out? I tried to use it to photograph “glass work” this being heating and manipulation of Borosilicate glass rods and tubes.
    This filter not being Didymium is totally useless as it does not work at the 589nm wavelength that is sodium flare.

    The difference between it and the glassworker’s glasses was nothing short of astonishing. A true Didymium filter removes all of the yellow flare.
    This filter took a tiny glare off but left at least 80% of the yellow sodium light behind.

    I believe this to be very important. As much of your article mentions glassworks and is stunningly misleading to anyone in need of a true Didymium filter.

    You should really amend it as it is basically wrong.


    • Ian Norman March 14, 2017 / 2:34 pm

      From what I understand, a glassworking Didymium filter is simply thicker and provides more filtration. I never recommended using the Hoya intensifier for glasswork, I merely mention another application of Didymium glass. Also, “much of [my] article”? I literally say “glassworkers” once.

  7. John Q December 1, 2016 / 12:33 pm

    Should I remove the UV protective filter before us this filter?

    • Ian Norman December 1, 2016 / 12:57 pm

      Yes, I would recommend removing a UV filter before using the intensifier.

  8. Marco Lanciani September 26, 2016 / 3:37 am

    Hi Ian,
    thank you, very interesting article.
    That you know of, are there solutions for lenses like the nikkor fisheye 10.5 2.8 DX, which uses rear filters?
    If your project goes ahead, please consider also filters for fisheye lenses: they are smaller and might be cheaper.

  9. Danny September 8, 2016 / 4:48 am

    I don’t know if I should be thankful or should I be hating you for the tips about this filter… I have been searching all over and different brands to try to get one on 82mm and there is no way to find them

  10. Tudor Vlad September 6, 2016 / 4:18 pm

    Great article.
    My question is how would this filter work with a T adapter going into a 2” focuser ?
    Is there a specific size I need to go for ?
    The camera is a Canon T5.


  11. Roger August 29, 2016 / 9:22 am

    I used the Hoya Red Intensifier this weekend and it looks like it filters the yellow out of the sky quite nicely. I see one interesting issue when I look at my images though — some of the brighter stars exhibit a star streak or a single spike in a circular pattern around the edges of the frame. Adjacent less bright stars do not exhibit any trail or spike. My camera was polar aligned and Polaris was actually to my back for the shots I took so I am wondering if there is a defect in the filter or if this behavior is to be expected. I did not notice anything odd when I shot with the filter in the daylight. Any thoughts? Here is a link to the image: https://flic.kr/p/LBK2Xq

  12. Nat August 21, 2016 / 4:25 am


    Upon examining the performance of the filter in light polluted areas I have ordered a 67mm version of this filter. I would have preferred 77mm but then knowing that it’s not coated, using a hood would be a good idea and I can order a bigger size later for tele lens work. Shipping to Istanbul is already problematic as we can no longer use PayPal around here 🙁

    My question is have you measured the amount of light loss using the filter (for astro work). Any color filter will have some light loss. The aim even is to have a light loss of unwanted light but still there should be some light loss (of star brightness or milky way dust). I’m wondering how significant this light loss is? Or in other words to get a similar star brightness and detail, how much do you need to increase the iso (or shooting time).

    It may also be that once you filter out unwanted light, even if there’s a light loss your signal to noise ratio (of signals which matter to you) will increase so there may be no need to increase the exposure in camera when you can do it more cleanly in post.

    Astro phorograhy in Istanbul is very difficult as you need to travel more than 100km just to get in a less light polluted zone. Hoping that the filter will help with that.

    • Christian Fiore November 8, 2016 / 6:08 pm

      Judging from his RAW samples, it’s roughly 2/3 stop loss.

  13. William Shaw August 12, 2016 / 3:17 am

    Looks like the supply in smaller sizes is improving again. Amazon US lists a few Hoya 67mm in stock (and will ship to UK) and both Adorama and BH suggest supply imminent.

    On another matter: IRIX lens have at long last shown some astro shots taken with their forthcoming 15mm F/2.4 on their Flickr site. This looks interesting as it claims to have an infinity focus lock and to take 95mm screw filters. No idea when you can buy it though, they said spring, then summer, and now that’s nearly over. Maybe Ian could put it on his list to review. It looks like it will come in priced a bit more than the Samyang but those features and the 2.4 aperture are all nice to have.

    • Edward De bruyn August 13, 2016 / 12:42 pm

      Also good news here for the 77mm, mine ordered and delivery and service is OK !!!
      So still 29, 30 minus 1 for me 🙂
      See mail from Event Cameras after a question to mail me regarding disposability of the 77mm:
      Good morning. Just wanted to let you know that we do have the 77mm Intensifiers back in stock. We received 30 piece in total so we should be in stock for at least a couple days. You can find them on eBay here: http://www.ebay.com/itm/Hoya-77mm-Intensifier-Red-Enhancer-Filter-MPN-S-77INTENS-/232046845529?
      Please let me know if you have any additional questions.
      Deven Morgan
      Event Cameras

  14. max August 8, 2016 / 2:33 pm

    sorry if you posted this somewhere else, but is your A7S modded (spectrum enhanced) or stock? You’re getting some nice emission nebula signal (lagoon nebula especially in your third sky shot) and I’m just wondering if that’s reflective of the performance of the native sensor (and IR rejection filter) or a camera mod job (if modded, by who?). BTW, from the spectrum you posted it looks like this filter has a significant dip in the ~530nm area which is doubly ionized oxygen – a big emission nebula line. Could explain the subdued nebulosity in your Orion shot. Still looks nice for landscapes but maybe not as good as a dedicated broadband nebular filter

  15. Gary July 27, 2016 / 6:52 pm

    Hi Ian,

    Sorry if this appears as a duplication. I tried commenting yesterday but it didn’t seem to take.

    I’d love to get into astrophotography and it looks like a filter like this is the way to go. Have you had good results with any other similar equipment?

  16. TF July 6, 2016 / 11:03 pm

    Get review. I can’t find one in 46mm (for an Olympus 12mm f/2). Any suggestions?

    • Joe August 9, 2016 / 1:04 pm

      You can get a step up ring adapter. The Hoya intensifier is available in 49mm so just get s 46 to 49mm step up ring adapter and you are good to go. The step up ring is less than $10 on amazon

  17. Ray June 23, 2016 / 5:10 am


    Thanks for a nice review. However, this is far from being a new idea – you should really have given credit (or at least a nod) to some other people and businesses who have done it some years before you and who gave you the idea. Unfortunately you didn’t, and it’s clear that this has led some of the commenters here to think you came up with the idea (e.g. Allen Bluedorn: “Hi Ian. What a great find!”)

    There are numerous examples on the web of astrophotographers who were already using Redhancer/Intensifier/Didymium/Neodymium filters for deep sky photos. I am one of them – see my 2013 comparison shots here for example:

    …but I in turn learned about the idea from the astronomical equipment manufacturer Baader, who created the original “Moon and Skyglow filter”:
    Link …”*Transmits a maximum of light, while blocking unwanted skyglow and many street light emissions.”

    • Ian Norman June 23, 2016 / 7:09 am

      I never claimed to have developed this idea. I originally learned about using a Didymium filter from an article on Noctilove and decided to test it myself in the context of landscape astrophotography for our readers. I think it was a good find.

    • James July 16, 2016 / 11:03 pm

      If everyone follows your suggestion, there is no article over the internet. Like Ian said, he never claimed he invented or found a new way. Not exactly sure where your envy came from.

    • Heidi September 9, 2016 / 8:22 am

      His post never claimed he founded the idea. He said he found the product and was testing it for himself.

  18. Anthony Roggio June 17, 2016 / 9:15 am


    Thanks for the reply. I traversed the entire Interwebs, and in my travels I was only able to find a 72mm Hoya Red Intensifier rather than the 77mm I needed. After much consideration, I decided to not experiment with the Tiffen because your results with the Hoya were so outstanding. I ended up purchasing the 72mm Hoya and a step-down ring adaptor. I’m hoping the vignetting won’t be too terrible when attached to my Samyang 16mm f/2.0 lens.

    Also, that is an outstanding idea creating your own universal Didymium filter as there is clearly a relatively sizeable market for it. I believe after you posted the article regarding the Hoya, those filters completely disappeared from every single outlet they were available through, both online and in stores.

    I can’t wait to try it out on my upcoming trip. Should open up more possibilities of places to go that are a little bit closer to home in areas where the light pollution would normally be a little too noticeable to achieve high quality results.

    Anthony R.

  19. Yusuf June 16, 2016 / 6:44 pm

    Ian do you think you will have same eary samples of the glass your sourcing?

    • Ian Norman June 23, 2016 / 9:48 am

      I’ll post samples of the results from the prototypes before I open orders.

  20. Anthony June 15, 2016 / 2:29 pm

    In your expert opinion, do you believe that a Tiffen Enhancing filter is basically the same thing as the Hoya Red Intensifier? I cannot for the life of me find a 77mm Hoya anywhere on the entire Internet, or even at any local shops. Would love to get my hands on one prior to a trip I am going to take to the Sierra Nevada’s in early July.

    • Ian Norman June 16, 2016 / 1:00 am

      Yes, I believe that the Tiffen should give very similar but maybe not identical results. All of them use Didymium in the filter and that should affect the spectrum similarly. Color balance might be slightly different between glass manufacturers.

      On another note, and for others follwing this thread, I’m in the process of trying to source raw Didymium glass for manufacturing square style light pollution filters myself as a new Lonely Speck product alongside the SharpStar2. I’m still in talks with glass manufacturers but I have made good progress at finding ones that I think will be relatively economical, maybe even competitive of I can get enough demand. There’s still a lot to do (testing, packaging, etc.) but we’re going to try to make it happen.

  21. Edward De bruyn June 9, 2016 / 1:56 pm

    Just got two filters, one of them was Hoya. The Hoya seems to work almost to good…
    Incredible, the stars are back even in a light polluted sky.
    For me (Belgium) it was impossible to get buy this filter in Europe, so ordered the filter (52mm) at EventCameras.com and had the filter after 14 days without any problem!!!
    So ordred immediately some other diameters, don’t like to change them to much in the dark…
    Also working on a possibility to mach such kind of filter to the Samyang 14mm, should say work in progress….but I’m almost very confident it will be OK.
    Will only test and work with Sony A7, A7r or A7s in the first place…
    So it’s 22:47 and still rather clear, I’ll have to wait another hour or two (Belgium) to get darker a sky…impatient and we will see.

    Sorry about the incomplete website..

    Norman: Learn a lot form you and thank you for sharing your experience !!!!

  22. Arda Ates June 8, 2016 / 8:22 am

    In London It’s totally out of stock. Couldn’t find it anywhere in any size.
    Thanks Ian :p

  23. John Link June 2, 2016 / 4:10 pm

    Yes, if you purchase this filter and it looks green or blueish don’t worry. Its just the lighting you are viewing it under.

    Thanks to Event Cameras for pointing this out:
    The Red Enhancer is the only Hoya Intensifier that receives the red “Intensifier” sticker that is in the upper left hand side of the filter case.
    The UPC code on the back of the filter case, which should be: 024066017345.

    • Roger August 19, 2016 / 2:47 pm

      Sure enough mine looks green indoors and blue outdoors. UPC and sticker are correct. Histogram indicates that there is more red and green with the filter on than without. Is that to be expected? I would have expected only more red.

  24. Bryan May 31, 2016 / 9:30 am

    Nice review Ian. I just bought some for my setup. A 77mm and a 67mm. They are not the Hoya ones though. They are made by SunPak.

  25. James Watson May 30, 2016 / 2:29 pm

    Hello Ian,
    Which would you recommend for M.W. shots, Samyang 14mm that cannot use this filter or Samyang 16mm that can use a 77mm version of this filter. Thank you.

  26. Andy May 27, 2016 / 11:27 am

    Thank you Ian for this interesting article. As I already have a few LEE filters (including the holder) I wonder if there’s a LEE filter that could do the same job as the Hoya Enhancer Red / didymium.

  27. Emil May 19, 2016 / 9:13 am

    I actually asked a friend of mine in the States to buy it and send it to me in Europe.

    Endeed Ian, your disturbed the force 😀

  28. stephane May 17, 2016 / 4:25 am

    hello !
    thanks !
    on Amazon, I can not find a filter diameter 77mm …

  29. Jim Abels May 16, 2016 / 6:21 pm

    Thanks for the info Ian. I’d love to test this out in New Jersey. There is plenty of light pollution out here but I’ve found ways to still capture the Milky Way. By using some of your ideas, I’ve captured and processed the heck out of the images to get basic details in orange/red areas on a lp map. This filter should help a lot in the heavily polluted areas. Once I get my copy, I will test and report back. You can see my work on IG @jimabels I found a source of the filter here: link

  30. Steve Baldwin May 10, 2016 / 10:44 am

    Hi Ian
    Seems that both Amazon and B&H are out of stock of the 77mm version. Only B&H seem to think they will have stock in the next few weeks. Are there any other outlets in the US who sell it? In the UK I have been told it is discontinued!
    Many thanks for a great article.

    • Ian Norman May 10, 2016 / 10:54 am

      I think I disrupted the standard flow of Hoya Intensifiers around the world with this article. Before I published, it was in stock everywhere! I’ll try asking B&H what they know about getting in more stock…

    • William Shaw May 12, 2016 / 3:56 am

      I asked the UK Hoya distributor Intro2020 to consider importing the enhancer. They said they’d need to look at an order of 10 before they’d quote a price. “discontinued” = “not worth our while”? I will be very interested to know if Ian has any luck sourcing square or bigger ones at a sensible price. I wonder if the makers would sell more if they highlighted the didymium suppression of yellow street lights rather than droning on about enhancing somehow.

  31. Dave Rosenthal May 9, 2016 / 11:26 pm

    Hi Ian,
    Thanks so much for all your hard work, great information and willingness to share. I just received some Hoya intensifier filters ordered from B&H for my Sony a6000 setup and was a little confused. They both have a slightly bluish hue to them; not pink and yet they say “didymium” on them and seem to help filter out night sky light pollution with a quick test. Is it possible that not all of them have the pink tint? I am just trying to make sure I have the correct ones. The part #’s ordered were 62mm – B&H # HOE62 or MFR # S-62INTENS and 49mm – B&H # HOE49 or MFR # S-49INTENS.
    The spectral response appears to be correct looking on Hoya’s website.

    Thanks again for all your help…

    • Ian Norman May 10, 2016 / 11:03 am

      So I looked into this a little bit more and it seems that with the two intensifiers that I own (both are S-XXINTENS part numbers), the color of the filter appears different under different light sources. Indoors, or under incandescent lights, it appears distinctly pink. Outdoor, under sunlight or shade, it appears blue. Is this perhaps the cause of the difference you are seeing? Either way, I probably wouldn’t worry about it too much if it seems to be working properly.

    • Dave Rosenthal May 11, 2016 / 8:52 am

      Hi Ian,
      You are correct!! I checked again this morning indoors and it has a slightly pink hue. Interestingly enough I walked around the house and it was pink in some rooms and blue in others…and varied depending on background. Just in case others are questioning it..

      Thanks again.

  32. christopher May 8, 2016 / 2:12 pm

    I recently tried the Hoya Intensifier filter on a Rokinon 24mm f/1.4 during an astro excursion in Northern New Mexico. I was very impressed with the light pollution filtering abilities of this filter. Just bought the 67mm thread version for my 12mm lens.

    • Ian Norman May 24, 2016 / 7:05 am

      Awesome to hear! I’m certainly liking mine!

  33. James Watson May 5, 2016 / 3:46 pm

    Which would you recommend for M.W. shots, Samyang 14mm that cannot use this filter or Samyang 16mm that can use a 77mm version of this filter. Thank you

  34. Anurag Daware May 4, 2016 / 9:28 pm

    Hi IAN,
    I see there 2 types on amazon website:
    Hoya 77mm Intensifier Red Enhancer Filter
    Hoya 72mm Red Intensifier Glass Filter
    Except the mm difference, which one are you reffering to?

    • Ian Norman May 5, 2016 / 12:47 am

      Those are the same from what I understand, except for their different sizes of course.

  35. José May 4, 2016 / 9:13 am

    Ian, thank you very much for the valuable information!

    I have a few questions if anyone cares to advise. I’m from Europe but I have a friend who should be going to the US soon and may be able to get this filter for me.

    I would love to try this on my Samyang 14mm (no filter threads). Since the clip-on version doesn’t seem to exist for now, at least at a reasonable price, would it be in any way viable to somehow attach a 77mm one in front of the lens – cheap DIY style ?

    Some of you mention vignetting. So for instance if I want to use this filter on a 52mm lens, should I do the obvious and buy the 52mm size, or would it be better to buy a bigger version and use step-up rings to make up for the difference?

    Thank you very much in advance for any help on this!

    Best wishes,

    • Emil May 19, 2016 / 9:20 am

      Hi Jose,

      14mm Sammy is to wide and the front element is big to use 77mm filter on it. You will have severe vignetting and I am not sure if it worth doing this. You might consider to use different type of lens.


  36. Abuko May 3, 2016 / 11:23 pm

    I’m using the Tokina 11-20 which runs 82mm filters. This only goes up to 77mm. Any good options for 82mm?

    • William Shaw May 4, 2016 / 3:56 am

      New, but for a price, there is still some Tiffens around in size 82: link

      But I’d suggest loitering on ebay looking for used Tiffen or Singh-Ray to try to get sensible cost. A Tiffen 82 went for $56 back in Dec.

    • Ian Norman May 4, 2016 / 4:04 am

      I would suggest the Tiffen that William Shaw mentioned. In the meanwhile, I’m contacting manufacturers to see if I can maybe get some of these in bulk, perhaps even in a square filter size. The Tiffen Cokin P one is ridiculously expensive and I want to find a cheaper alternative.

    • Abuko May 4, 2016 / 8:38 pm

      Thank you, William and Ian!

  37. Wim April 29, 2016 / 4:32 am

    Great post Ian!

    The Hoya Intensifier seems impossible to get in Europe. Amazon doesn’t ship here, and B&H changers almost double the price for shipping and customs handling.

    I see German made B+W filters include a Red Enhancer filter in their offering, i.e. the B+W F-Pro 491 Redhancer Filter. Judging from a graph I found in a review, it seems to block out the same parts of the spectrum as the Hoya. Cannot find a lot of info on it though, but I assume it would allow the same application as the Hoya?


    • William Shaw April 29, 2016 / 6:33 am

      Wim – are you sure about Amazon – they sent mine to the UK from the US without any problems at all. Maybe UK is not part of Europe… I found the B+W thing on the web but no-one who could supply it, and it appears Tiffen are not producing enhancers any more – my attempt to order one kinda vapourized.

      The only other option I found, although it is a LOT more expensive: the Singh-Ray enhancer does the job of cutting the street-light yellow – my 95mm just arrived and I think it is more neutral in its colour balance than the Hoya (the yellow acquires a magenta-ish tinge if you look at a street light through the Hoya, and this is absent from the Singh-Ray). Singh-Ray is an (expensive) option if you must have larger or square, or low-profile options to address vignetting concerns. Though on my Nikon 20/1.8 there is no vignetting from the Hoya 77mm. For the money it is clearly a great choice, as Ian’s great review points out. I’d be very interested to hear more affordable solutions for sizes above 77mm and rectangular shapes. I saw a rumour somewhere that Optolong were working on clip-ins for Nikons – anyone heard that or know if it’s real?

    • Michael May 3, 2016 / 11:22 pm

      Hi all
      I tried to get an Hoya Enhancer red as well here in Germany. From the german importer for Hoya it isn’t available due to “economical” reasons. Importing from US is quite expensive.
      Unfortunately the B+W 491 Redhancer is not in the production range at B+W anymore, but it seems few dealers have it in stock. I found one used in very good condition.
      The B+W 491 is also made from Didymium glass and shows a similar absorbance spectrum.
      I will give a try on my Samyang 12 mm and my Fuji X-E2.


      @Ian: GREAT!!!!!!

  38. Allen Bluedorn April 27, 2016 / 2:04 pm

    Hi Ian. What a great find! Thank you for writing this review about it. One question I have is do these filters significantly reduce the amount of light transmitted through them? Circular polarizes typically reduce light transmission by two stops or so, and I wonder if these intensifiers reduce light transmission too (other than that filtered out, obviously). I would guess that they do a little bit, but if it is only one-eight or one-fourth of a stop, that wouldn’t make much difference. And given the post processing challenges with this tyPe of photography, I agree that the better the out-of-camera image, the easier the pp will be.


    • Ian Norman April 27, 2016 / 11:10 pm

      Hey there Allen!

      The intensifier seems to perhaps diminish light by 1/3 of a stop at the most. But it depends. It’s very subtle and almost intangible for regular daytime shooting. For astro, when there’s a significant light pollution source present in the photo, the effect seems greater just because you no longer have such a significant source of light (the light pollution) hitting the sensor. Even so, it’s not enough of a change to warrant alternative exposure settings.

    • Allen Bluedorn April 28, 2016 / 6:46 am

      Hi Ian. Thank you for that information. As I hoped, it is a difference small enough that it doesn’t makes a difference. I will be ordering one shortly, and rest assured that I will do so by using one of the links on Lonely Speck. Got to support the home team!


  39. SethRyan April 27, 2016 / 1:51 pm

    I will pick one up; thanks for the write up. This should be a big help especially in the less than ideal conditions for night sky viewing on the East Coast.

  40. Matt Selby April 27, 2016 / 10:54 am

    Interesting post, I definitely think the shots with the filter look better, but I can’t help thinking this is just filtering out the red hues giving you a cooler image which looks better for astrophotography, and also something one can remove in PP. The other thing about a circular filter is I would have to use it on my 24-70mm lens which isn’t really wide enough for shooting the MW @ 24mm, I’d usually use my Nikon 14-24mm f2.8 but that lens doesn’t allow circular filters.

    • Ian Norman April 27, 2016 / 10:58 pm

      It’s certainly giving a cooler image in this case, but only because it’s removing the light pollution. The Galactic center remains warm and bright with oranges and yellows still present. Also, subtly colored nebulae still retain their color. In normal daytime shooting, the filter shows no effect on white balance at all.

      The advantage over trying to remove light pollution in post is that we will have better results earlier. The result straight out of the camera ends up having a better signal to noise ratio. Here the light pollution is a form of noise that obscures the part of the image that we care about.

      I, too, am looking for a good square filter or similar solution for lenses outside the range of thread sizes.

    • Don May 5, 2016 / 12:13 pm

      I had a similar question as Matt, Ian. What is the advantage of optical filters versus twerking color balance in PP? Your discussion about signal to noise ratio seems essential, here. I was wondering if you could elaborate. If true, would the shadows (i.e. the black background) exhibit lower noise using the intensifier as compared to using a digital filter in adobe? Take, for example, the overhead shot of Los Angeles or one of the other shots that is saturated with warm color.

      It would be interesting to see how a good post-process image compares with an image that was treated with the optical filter.

  41. Karan April 27, 2016 / 8:33 am


    Can you check on this.

    Thank you.

  42. Ilan David April 25, 2016 / 4:04 pm

    I can’t seem to find the Voigtlander 21mm Ultron filter (58mm) on Amazon or B&H . i see the blue one but not the pink. Can you please specify the UPC #?
    Is it this one?

    • Ian Norman April 25, 2016 / 10:57 pm

      That’s the one.

  43. Tarun April 24, 2016 / 7:07 am

    How is the vignetting on this ? I recently gave a try at 77m optolong UHC filter to remove LP but had heavy vignetting .

    • Ian Norman April 24, 2016 / 11:23 am

      I have noticed absolutely no vignetting caused by the filter.

  44. William Shaw April 22, 2016 / 2:37 pm

    I have been using the 77mm Hoya red enhancer on my Nikon 20mm/1.8 for a month now over in the UK, in my back garden which has a yellow street light nearby. It works really well! The manufacture of didymium filters does seem to have declined since computer-based image processing has become so easy, but I find it really useful to kill the yellow fuzz at the initial stage. They are not sold directly in the UK – the Hoya distributor does not import them – but you can get them from the US.

    I have been struggling to find larger didymium sizes. The Tiffen 95mm seems to have been discontinued and I have been trying to source the Tiffen 4inx4in square to use with the Cokin Z system – I am not sure if one is on the way right now. Singh-Ray have literally just sent me one of their enhancers to try – their web site wording suggests it works slightly differently from the Hoya, but some e-mails confirm it does suppress the yellow, so I am giving it a go on a trial. They also make some low-profile ones that might mitigate possible vignetting on UWA lenses. They do a range of larger round and square sizes, at (for a serious price!)


    Anyway, they do a 95mm that will fit on my current 200-500 Nikon, the Zeiss 15/2.8 and the interesting forthcoming IRIX 14/2.4 – I’d be interested to know if other astros have had luck with the Singh-Ray version. They do a range of sizes – it’s a shame the bigger ones are so expensive.

    As far as I know the “LPS” filters use a totally different mechanism which does not work on UWA, but the didymium recipe seems fine, as per Ian’s photos. My Sinbh-Ray is due next week so I will be trying it on the next cloud/moon free night after.

    • Ian Norman April 22, 2016 / 8:15 pm

      Some very useful information here William!

  45. James Probus April 22, 2016 / 1:28 pm

    Is the use of this filter at all redundant considering that Lightroom can make adjustments to mimic these same effects? Is it worth it get better looking photos right out of the camera? Thanks!

    • Ian Norman April 22, 2016 / 8:18 pm

      I think that it’s still very helpful to use the filter, particularly because it seems so specifically targeted towards removing the most problematic colors, something that’s not very easily done in post without affecting other parts of the image. Getting the image as good as possible in camera will usually always yield better final results.

  46. Ugo Cei April 22, 2016 / 12:30 am

    Hi Ian and thanks for the review. I would like to buy this filter, but I’m a bit confused as to which one I should actually get, as there are red, blue, green and other variants of the intensifier. I guess I should get the blue one, but the one that looks pink in the photos is the red one, so I’m not really sure. Can you please clarify?

    • Ian Norman April 22, 2016 / 5:27 am

      Hi Ugo! It is actually the Red Intensifier.

    • Ugo Cei April 22, 2016 / 11:47 am

      Interesting… so the red intensifier will filter out the yellows, if I understand correctly.

    • Ugo Cei April 22, 2016 / 11:52 am

      Alright, I had some Amazon gift certificates to spend, so I ordered a 67mm one for my Samyang 12mm. Bring on those night skies!

    • Ian Norman April 22, 2016 / 8:20 pm

      Yes, the red intensifier actually filters out the yellowish orange part of the spectrum.

  47. Sriram Murali April 21, 2016 / 7:14 pm

    Absolutely wonderful. I’ve learnt a lot from you in terms of best lenses to use for astrophotography, post processing methods and now this! I commend your attitude towards sharing valuable information with others and people hardly do that these days to the level that you do. You are indeed a great man. Thank you!

  48. Vincent April 21, 2016 / 5:22 pm


    does this work for UWA lenses? what’s d difference between this filter n the LPS filter. it’s a known fact that the LPS filter don’t work well on lenses <35mm.

    • Ian Norman April 21, 2016 / 10:30 pm

      Yes it seems to work just fine on the 21mm which is considered “super wide”. I think it would work fine on shorter lenses as long as the lens has a filter thread.

  49. Anthony Roggio April 21, 2016 / 4:38 pm

    Any shots with this filter in a heavily light-polluted setting? Somewhere near a majoy city maybe?

    • Ian Norman April 21, 2016 / 11:01 pm

      I just updated the post for you Anthony!

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