Nick Carver Photography Blog

Photography Tips, Tutorials, & Videos


Gear Review: The Slim UV Filter

I’m a fan of UV filters for DSLR cameras (here’s why). With a high-quality UV filter, you can get some peace of mind from a small investment without any penalty. High-end UV filters won’t degrade image quality regardless of what the Flickr forums tell you and they will protect the front of your expensive lens from sea spray, dirt, scratches, and even some serious falls.

I’ve also written about what I think is the best UV filter on the market (read that article here). So then what’s left? You know I’m for ‘em and you know what brand I like...

Well there’s one sneaky little option when it comes to purchasing a UV filter that you should know about: the slim UV filter.

The only difference between a slim UV filter and standard UV filter is that the slim version has no front thread on it. See, regular screw-in type photography filters have a male thread on the back that allows you to attach it to your lens (duh) and they usually have a female thread on the front of the filter that allows you to attach another filter on top of it, and another one on top of that, and another and another...

Gear Review: Slim UV Filter
Standard UV Filters have a front filter thread like this

The slim UV filter, on the other hand, typically does not have a front thread. You can’t attach a filter on top of a slim UV filter. They are basically flat on the front - the outer ring is flush with the glass.

The idea is that with ultra wide-angle lenses, there’s a risk of vignetting from a standard UV filter. Vignetting is when the corners of your photo are darkened because the filter sticks out in front of the lens too far. It’s like looking through a tunnel. So someone came up with the bright idea of slicing off that front filter thread to reduce vignetting. It’s a smart idea. And hey, it’s not like anyone was using that front filter thread anyway...

So some say that for wide angle lenses, you need a slim UV filter otherwise you’ll get vignetting. Well, not exactly. A standard UV on even the widest angle lens might create vignetting, it might not. Depends how they engineered the lens. For instance, I have a Canon 16-35mm lens on a full-frame camera, which is the widest angle available second only to fisheye. My standard B&W 77mm UV filter (not slim) creates no vignetting even at 16mm. Take a look:

Standard UV at 16mm
Even at 16mm, a standard UV gives me no vignetting

But maybe your wide angle lens does get vignetting with a standard UV filter. If that’s the case, you really have just 2 choices: either use a slim UV filter or don’t use one at all. Just remember that this filter is going to be on your lens all the time. So if you use a slim UV filter, your lens will no longer have a front filter thread available. And here’s the thing about having no front filter thread: you can’t use any other filters (goodbye polarizer and split ND filters) and you can no longer use a lens cap.

Sure, you could remove the UV anytime you want to use a polarizer or split ND, but that kind of defeats the whole point of having a UV filter to protect your lens. I’m betting that if there’s any time you’ll drop your camera, it’ll be when you’re trying to unscrew a UV and replace it with a polarizer. And sure, slim UV filters come with a replacement lens cap that slips over the top like a glove, but it’s going to pop off your lens much more often than a standard pinch cap.

So before you buy a slim UV filter, weigh the pros and cons of having no front filter thread in exchange for no vignetting. But most importantly, see if a standard UV filter is even going to create the vignetting you’re worried about.

And by the way, if you’re interested in learning more about filters for digital photography - a subject I’m very passionate about - check out my Filters for Nature Photography online course.

Photography Classes Orange County: Camera Filters


Photography Classes Orange County: Camera FiltersThe next session of my Filters for Outdoor Photography class is on Saturday, February 8th at 10:00am. This Orange County photography class meets just one Saturday at 10:00am-12:30pm. From UV filters, to polarizers, to split ND filters, to white balance, this class will teach you how to use all the most important camera filters for outdoor photography. I consider camera filters my most important tools for creating great landscape photos and they are an integral part to almost every type of outdoor photography. I've structured this class to not only teach you how to use these filters, but also to help you sift through the countless options at the local camera store so that you'll know exactly what to buy and what to not waste your money on.

Don't be fooled by the marketing of software companies - camera filters are just as useful in digital photography as they've ever been! Find out what filters Photoshop can never replace and which filters are most important to keep in your bag. Learn how to avoid blown-out skies in your landscapes with split NDs, how to get richer colors with a polarizer, how to mimic a warming filter with your white balance, what the real advantages to RAW files are, and more!

With a small class size of only 12 students max, you'll get personalized attention and you'll never be left behind. Plus, my photography classes Orange County are highly rated amongst previous students. Please browse through my Yelp reviews or read the testimonials on my website here to see what previous enrollees had to say.

Here's what a previous student had to say about my classes:

"I have taken a course at our community college and a few on line courses and have not found any to be as informative and easy to understand as Nick's instruction."

- Sheri P.

Don't wait until this class fills up! Reserve your seat today for just $39! More details about this course including enrollment information can be found here.

Common Misconceptions: You Don’t Need Filters for Digital Photography

The Misconception:
Photoshop (and other image editing programs) have replaced traditional filters. I can do everything in Photoshop that photographers used to do with filters.

Why This is Wrong:
Whether you're talking about a digital sensor or a piece of emulsion, photography is all about recording light. The whole purpose of traditional filters is to alter the light on its way to the sensor or film so as to achieve an effect. Using Photoshop to mimic a filter is simply "pushing pixels." It's altering ones and zeros. It's trying to change the light after the fact.

Let's take graduated neutral density filters for instance. There are the real deal and there are imitations built into software like Lightroom. The way true graduated ND filters work is by darkening the light coming from the sky as it makes its way to the sensor. The way the "graduated ND filter" in Lightroom works is by darkening blown out pixels to make the sky appear darker. So with the real McCoy, the bright light is tamed down so that the sensor can actually record the sky in all its detail and color. With the cheap imitation, a blown out sky with no detail at all is artificially darkened without ever recovering much more detail.

Check out this side-by-side example. The image on the left was taken with no filters and the image received almost no post-production work. The image on the right is my attempt to digitally mimic a graduated ND filter on the exact same file. I used the dodge and burn tool in Photoshop along with gradients, layers and curves. It took about 10 minutes to do all that work to just one image.

Graduated ND ImitationYou'll see that the sky is a bit darker and there is a little bit more detail, but it's really no replacement for the real deal, as illustrated below. In the next comparison, take a look at how much better the image is when I utilized a simple traditional graduated ND filter. The image on the left is the same one as above - no filters with heavy post-processing. The image on the right is the picture taken correctly with proper filters with almost no post-processing work. Time spent on the computer for the image on the left: about 10 minutes. Time spent on the computer for the image on the right: about 10 seconds.

Digital Grad ND vs Read Grad NDLook at can actually see detail in the sky! With a simple $40 filter and zero time spent in Photoshop, I went from a blown out sky with no detail to a beautiful sky with lots of detail.

No filters vs a Grad ND

So you can see that my Photoshop imitation of a grad ND doesn't even hold a candle to the real grad ND. It doesn't recover detail in the sky, it doesn't capture the color in the clouds and it doesn't preserve the quality of the original file. More work with worse results. I don't know about you, but I like to worker smarter, not harder.

Here's another variation on this picture that, again, utilizes true grad ND filters and received almost no post-processing.

Using Graduated ND Filters

Same goes for circular polarizers. Those filters cut through reflections on everything from water to windows to foliage. There is no replacement for that in the computer!

The Truth:
Filters are just as important today as they were with film!  There's no replacement for altering the light on its way to the sensor. And no matter how much money you spend on Photoshop and all its plugins, no piece of software can travel back in time to the moment you clicked the shutter and alter the light before it hits the sensor. Especially when it comes to blown out pixels, Photoshop just can't work miracles. If pixels are blown out, there is literally no detail to be recovered. And if you're thinking, "But Nick, what about HDR." Well...don't get me started.

My Thoughts and Rants:
I don't know where this idea started that just because everything's digital now, we don't need traditional filters anymore. I have a sneaking suspicion that it's all rooted in marketing from image-editing software companies. They want you to buy software, so they market their products as a replacement for filters. Just like diet pills trying to convince you it's a replacement for proper nutrition and exercise.

But regardless of where it came from, this mentality drives me nuts! To me, it's like using software to correct a horrible, pitchy musician who really has no business singing in the first place. Instead, let's ditch the software and just get someone who can actually sing. Is that really such a novel idea these days? What would the world be like if we never used Auto-Tune or Photoshop ever again? All the horrible musicians and photographers would drift out of sight like dregs at the bottom of a dirty bucket of water. Then all the actual talent would float to the top. Oh, also all of our supermodels and celebrities would suddenly look flawed and human. God forbid!

Bottom line is this: using software to mimic proper use of filters out in the field is the work of incompetent photographers. They can operate software, but they can't operate a camera. But don't fret if you fall into this category. We were all incompetent photographers at one point. But don't turn to software to fix your images - just become a better photographer through study and practice! Then you can save the $600 you would have spent on Photoshop for something really valuable, like filters and a tripod...or your mortgage.