Okay- Apologies for being so long. I haven’t been distracted, I’ve just underestimated how much work this would take. This article kept growing and growing… I’m now calling it a mega-article. I might end up doing these now and again, but I’ll definitely prepare ahead of time. I started researching and testing for this back in autumn, but didn’t really plan to write it until January. I didn’t feel like delaying it part-way through, so spent the last month writing and polishing it.
Okay… on to the article:
A couple of months back, I wrote about how disappointed I was with a UV filter that I purchased. It was nice, didn’t seem to distort my photos at all, and was lightweight. There was only one problem… it did not block ultraviolet light at all. I mean, at ALL.
I CAN CHECK THESE THINGS!!!! UV COATING MIGHT BE INVISIBLE TO THE NAKED EYE, BUT IT SHOULDN’T BE FOR MY CAMERA!
Honestly, I was a little angry at the time- maybe not as much as I pretended to be in the post, but I still felt cheated. However, since the store I bought it from has a good refund policy, I got over my anger quickly.
Still, I was wondering just how much of an issue is this. So, I thought I’d take a look. I went around to a few stores and bought some different brands of UV-blocking filters(which I’m just going to refer to as UV filters for this post). I specifically DID NOT look for online ones- the filter I bought are all the ones available in my local stores to a general consumer. More importantly, all the stores have a good return policy, so I could return them until I found a good one.
This isn’t going to be as much as a rant this time; I’m going to try to do this all professional and sciencey. For this, I will use the scientific process as I learned it in school: Question; Hypothesis; Methodology; Boredom; Getting angry with American spelling being the default for Spellcheck; Turnign Spellcheck off; reelizing that I’m a bad speller; Getting distracted by trying to change the Spellcheck language; Forgetting what I’m writing; Making some bad jokes; Eventually trying to make my ramblings into a semi-coherent blog post; Conclusion.
Question: Do UV-blocking filters work?
Hypothesis: UV-blocking filters might work, unless they don’t. Or not.
Methodology: I’m going to evaluate the filters on several criteria. Each criteria will be on a scale from one to five.
1st– How does the packaging look? A good package is not only clearly informative, it can also be a work of art, implying the use for the product and who is it geared for. A professional, minimalist package would appeal to professionals, while an elaborate package appeals to people who delight in the wonders of photography and improving their skills. The packaging score will then count for 0% of the final score, because I really don’t care about packaging.
2nd- How good is the protective case? Does it protect the filter, and is it easy to carry? This isn’t quite as useless as packaging, but if anyone is buying a UV filter solely for the protective case, there are cheaper options, like maybe buying an object called a ‘protective case’. I’m including this criteria because someone might be interested, and obviously not because all the filters I tested were completely worthless and I need some way of ranking them other than price. This counts for 5% of the total score.
3rd- Is the lens shiny and shimmery? This sounds like a joke, but I’m actually (semi-)serious about this; Several good UV filters I’ve seen have a strange tint to them, almost like an oily sheen, showing colours that change depending on the position of the sun and the angle the filter is being viewed at. If the lens doesn’t seem to reflect light oddly, It doesn’t bode well for how well it blocks UV light. The results are another 5% of the final score.
4th- How do the filters look through my full spectrum camera? My camera(A Canon Rebel T3i) has been modified with a full spectrum filter, allowing it to see into the Ultraviolet range. Not to brag, but my camera is probably much better than yours is at picking up ultraviolet light… And I really don’t mean to brag, because most photos look so much better WITHOUT ultraviolet light. That’s the whole reason for a UV filter.
What am I judging by? A good UV filter should look clear to the naked eye, but opaque or reflective in the UV range. Can my camera see any difference in the filter outside the visible range?
Unlike last time, I’m going for several types of pictures. I’ll take a photo with my short pass filter(which allows in UV, Violet, and some blue light), and one with the short pass filter combined with a Schott UG11 filter(which will block visible light entirely, only allowing in UV light from about 370-390 nm). A five means it appears black or completely reflective.
This is where you don’t want to mess up, as this is 35% of the final score.
5th- Does it block any non-uv light? Finally, I’ll check the filters with a Zomei 680 nm infrared filter… because… because maybe they forgot whether ultraviolet light wavelengths were shorter or longer than visible light. I’m sure it’s a mistake that anyone could make, even a professional company selling their filters in a chain store… look, the filters all suck, and I’m really reaching for some way to evaluate and rank them. If they block IR light, then maybe they at least put a little effort into designing the filter.
Once again, I’ll use a 5 point scale. 10% of the total, this time.
For numbers 4 and 5, I’m taking these photos on sunny days when possible. I’m not all taking the photos on the same day, because it really shouldn’t matter much to the final result. I took the photo when I purchased the filter, or the nearest bright day. There might be less UV light on one day than on another, but if the glass can’t block UV light an any significant amount, it should look transparent regardless.
6th- Florescent lighting. Because it seemed like a cool way to double check my results, I’m copying this video. I’m using a black light, and seeing if the filters cast a shadow. If they do, they are blocking the ultraviolet light, preventing the paper from fluorescing. If they do not cast a shadow, it means six more weeks of winter.
The filter on the left is clear, but because of those ‘off colour reflections’, it appears blue in this photo under normal light. I’m using a fluorescent black light for this; It is the same distance from the paper in each photo. These photos were taken in my laboratory, a dark room with no windows and all other illumination turned off to ensure a controlled environment. It is for this reason that I designed my laboratory to…
…it was my bathroom. I went into my pitch-black bathroom with a camera and UV lights. I don’t know what that says about me. I also don’t know what to say to anyone who walked into my bathroom to find a black light and a camera on a tripod.
My technique evolved through this test. Originally, I tried to have the filters stand, to better see the shadow behind them, but due to the long exposure, that didn’t turn out well. Eventually I just laid the filters flat down on the papers. The good filters look very dark, but that is not the filter itself. The filter is clear and the paper can be seen through it, but it casts a shadow on the paper beneath(technically, it blocks the florescence, but to the eye, it appears to be casting a shadow).
Every filter blocked at least a small amount of light from hitting the paper in this test. In some cases, the difference isn’t noticeable in the photo I took, but was to the naked eye. However, UV light can be absorbed by ordinary glass, so a faint light reduction isn’t enough for me to say the filter actually works. I have a working UV filter to compare them to, remember.
The score for blocking florescence counts for 35% of the final again.
A side note: I also borrowed a short-wave UV light used for rockhounding(purportedly emitting most light in the 270 nm UV-C range, but I can’t confirm that). I didn’t post these results, as I needed such a long exposure that the photo didn’t look good and every filter tested performed pretty much identically, but I’ll cover this in brief here. In the below photo, I have my unknown lens, the BG40(designed to let near UV light through), and a JYC filter, under a regular incandescent light.
The BG40 does appear blue in real life as well, but the unknown filter is clear(looking a bit like a polarized filter), but has off-colour reflections, so it appears blueish as well. The JYC is clear both in the photo and to the naked eye.
With a UV-C lamp:
The unknown lens’s coating easily beats the other two, but it is the only filter with verifiable UV blocking abilities. Clearly, The BG40 blocks more than the JYC. At these wavelengths, I think that the glass itself is blocking most of the florescence. The Schott has the thickest glass, and it outperforms all the UV filters I reviewed. The thinner the glass, the less florescence they blocked. There were no exceptions other than my my controls(specifically, the eyeglasses and the unknown filter).
So, the UV-C light did result in a more of a shadow than the regular black light, but you camera should never need to worry about that. There’s another reason I didn’t include this in the detailed reviews. The atmosphere blocks almost all UV-C light. There’s not much data on how much damage UV-C light can cause to the human body, because so little of it reaches us. To sum up, if there is enough UV-C light to get past your camera’s lens and hot mirror, and affect the camera sensor, my review is not going to be much help. You do not need a better filter. Instead I suggest you turn off the camera, go to the emergency room, and rethink your life.
7th: Price. Because if you’re going to buy something useless, go for the cheapest one. 10% of the final score.
I’m not judging the price based on how expensive the item is, but rather is the price reasonable compared to the quality of the filter. A UV filter that blocks no light and costs $25 is gets a lower score than a UV filter that costs $40 and blocks a good portion of UV light.
Finally, I am specifically NOT judging how the filter might distort a visible photo or how well it protects the camera lens. Other photographers review with these criteria, and they definitely did a better job than I would have. That’s not what I care about; as I mentioned last time I wrote about this, that isn’t the point for me. There are filters that exist solely to protect the lens- they are called ‘clear filters’ and do not even claim to block ultraviolet light. If these filters are claiming to do it, they’d better live up to the advertising.
So, onto the reviews. I’m testing several filters. Each filter is being given its own page to review; there are links by the names.
Again, click on each name above or below for a detailed review.
Conclusions: … Well, I have no idea how I’m going to present this. I think it’s unethical to change the review standards after the review, but I probably should have refined my criteria farther, adding catagories such as ‘is it actually designed to fit on a camera’.
You know what.. I don’t care anymore. I’m stinking with my seven criteria(packaging, protective case, shininess, UV blocking(from Full Spectrum Camera), other light blocking (from a full spectrum camera) UV blocking(from black light), price). By these criteria, the top three UV blocking camera filters are:
1- My Eyeglasses: Okay, they’re not technically a camera filter, but, as I mentioned, I didn’t judge by how well it fits on a camera. I also specifically mentioned that I’m not judging by how much the filter distorts the picture… and I have bad eyes, so it’s REALLY distorted. My glasses are nicely protected in a hinged case. They have the violet coating, so my eyeglasses do an excellent job at blocking UV light, and performed the best in every UV based test. The resulting photo might be awful and blurry, but it is an awful photo that I can be positive has no UV light pollution! Congratulations, eyeglasses! You win the Parallel Views award for top UV filter of 2019!
2- The Mystery Filter: No packaging or protective cover, only the empty void. The mystery filter is good at blocking UV light, but my eyeglasses seem to be better. However, the mystery filter also blocks infrared light, something that my eyeglasses do not. It does not fit my camera, but possibly it would fit a camera? If your camera has a lens diameter between 55-58 mm, and maybe is slightly warped so that it is an oval, you’re in luck! This would be number one, but I have no idea how I got it, what it costs, what I had to give up in order to obtain it, or how to get another one, which means it drops a rank.
3- Schott BG40: I forget what the packaging looked like. I’m not going to blame my bad memory, so it must be Schott’s fault that the package isn’t memorable; it loses points for that… but again, I don’t care about packaging. The protective case protected the filter from damage from the nemesis of cameras everywhere: my dog. It wins on that front. The lens isn’t shimmery, but it is blue, so it gets middle score. Now, I wouldn’t recommend it as an ultraviolet filter, as the Schott BG40 is awful at blocking ultraviolet. To be fair to it, though, every filter below this one is also awful at blocking it, and unlike them, the Schott BG40 is specifically designed to ALLOW Ultraviolet light through, so it has an excuse. the Schott BG40 excels at blocking infrared light, which it is intended for, and none of the filters below even do that. it at least blocks something well, and it isn’t being sold as a UV filter. To be serious, the Schott BG40 isn’t cheap, but it is useful for a full spectrum camera and is one of my most used filters.
So, the top three UV blocking filters are the three controls I used. Not only that, but the Schott BG40 was only used as a control to set the lowest possible bar for the UV filters to beat. If they cannot beat a filter specifically designed to let UV light through… this isn’t going to go well, is it? Okay, onto numbers 4 and beyond.
Do I really have to?
First off, they’re all useless… None of them block UV light. . None of them shimmer, none of them block any light in the infrared range or ultraviolet range, none of them cast a shadow under a black light. They might look like they block a little bit of light in my photos, but even dollar store reading glasses block more UV light (As shown in my previous post).
Technically, the score is as follows (JYC at 25%, Hoya at 21.5%, Platinum at 14%, Techpro at 12%, Vivitar at 8%, and Bower at 7%). They are all complete failures. As a result, I’m dropping criteria 3-6. Instead, forget what I just said about not changing my review criteria. I’m throwing any half-assed attempt at objectivity out the window, and ranking them on how annoyed I was with them. With these results?
4- Nothing: A last minute contender! If you want a filter just to protect your camera, that’s fine, but it’s not what I’m judging by. By my criteria, a filterless camera blocks almost as much UV light as these filters do. It is also much cheaper and more portable.
5- JYC: No packaging; it came wrapped in bubble wrap taped to cardboard. It blocks no ultraviolet light, no infrared light, nothing. It is, however, very cheap, giving it the #5 place. I’m pretty sure it isn’t diseased, so it comes out top out of the filters I am actually reviewing. I do have a few uses for it, none of which involve blocking UV light.
6- Vivitar: It is completely worthless, and might block even less light than other filters, if that is even possible. However, it came in a kit with some actually useful filters.
7- Platinum: Professional looking package, and that’s it. The foam padding is nice for the filter. Does it block anything? no, it does not.
8- TechPro: Boring packaging, good protective case. It is a bit more expensive than #7 by three dollars, but the case is smaller and easier to fit in a pocket. Don’t ask about the lens. It’s another useless piece of glass. You’re buying a $24 protective case, be happy with that.
9- Bower: The package is very pretty, and is FULL OF LIES. Unfortunately, the protective case is too large for the lens and it slides around. It was on sale for $10 CDN, so it doesn’t get the last place. If I had bought it at the full price, it would be bottom of the list. Actually, it still is, as I’m pretty much down to judging irrelevant minutiae to rank these camera filters and they are all failures.
9: Hoya: It might be a bit better than the others at blocking UV light, or it might just be that I bought it midwinter, a month after I bought the others, and the sun was lower on the horizon even at midday. Either way, that very slight, possibly nonexistent, improvement isn’t worth the extra price. Hoya has a good reputation, and the complete failure of the lens and the price mean it gets last place.
Really? what am I supposed to say? Steal my glasses? Ask a Forseken One? Buy one of these completely useless filters? They aren’t even filters. They don’t filter anything!
…Look, if you have a digital camera, it is pretty much designed to block UV light from the beginning. The lens is designed to block most of the light(and probably has UV-blocking coating as well), the hot mirror inside will catch whatever gets past the lens, and the sensor isn’t sensitive to the light, so even if anything got to the sensor, your camera probably wouldn’t detect it. So, why would you need an extra filter?
…In fact, why did I need an extra filter? Why did I keep buying them? Is there something wrong with me? I tried so hard to find something good, and now I’m just sad and depressed. I’m surrounded by failure, and the only memento of my optimism is a bunch of returned item receipts.
…I hate my life. I’m going back to showing pretty pictures. At least they are worth looking at. See you all in a week or whenever.
To be serious for a moment: There’s a lot of humor(or at least my attempts at it) in this post and the linked reviews. My first drafts were fairly serious, but I found it boring both to write and to read(every UV filter tested had about the same results, and there was no fun way to write the same thing over and over). I added the humor just to make the article more entertaining. However, when it came to the actual tests conducted, I was serious with my methodology, and checked the results several times at different times of day and under different conditions. I also tested the filters with a triple stacked Schott UG11, Schott BG 40, and my short pass filter combination to ensure that I had cut out all infrared and visible light leakage; it did not change the results, but the longer exposure meant It was a lot harder to hold the filter in place, so I went with a double-stacked BG40 and UG11 filter combination instead. I did not fake any of my tests or my photos, and my only adjustments were in removing dust from the camera lens and adding labels.