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The Canon XL1 S is an ideal platform for exploring the potential (and necessity) of camera filters.

The skilled DV shooter knows the Curse all too well — the impenetrable blacks, the blown-out highlights, the hard ugly edges around objects. These are a few of the shortcomings we've had to put up with in exchange for the economy and opportunity that DV offers.

Yet despite the compromises inherent in the low-cost format, there is hope for breaking the DV Curse, and the solution may be as simple as selecting the correct camera filter. Two years ago in the December 2000 issue of Video Systems, I observed that DV shooters were increasingly being asked to do first-class work with little more than prosumer equipment. This observation would appear even more true today, as shooters seek ways to tone down the format's brassiness. This effort is made more difficult by most cameras' lack of tweakability. Most DV models are essentially closed boxes, thus, sadly excluding the shooter from critical compression decisions.

The Origins of the DV Curse

The DV curse stems in large part from the camera manufacturers' incentive to discard bits. The capturing, transferring, and storing of fewer bits translates into slower, smaller (and therefore cheaper) hard drives, camera transports, and interfaces. Using FireWire, for instance, rather than more expensive SCSI. DV's high efficiency (and high compression) sparked the current revolution on the desktop, bringing low-cost digital video to the masses.

Unfortunately, the popular DV25 format's high 5:1 compression means some 80% of the original picture data must be discarded. Obviously your camera is making some very tough decisions with respect to retaining picture information. Compared to DigiBeta with its relatively benign 2.2:1 compression, or Digital-S (D-9) at 3:1, your $3,000 DV camera has to work a lot harder to achieve a pleasing, artifact-free image than its far pricier cousins.

The issue then becomes who is making these crucial compression decisions. One would think that the shooter (whose career is on the line) ought to wield this essential power. But few cameras in the $3,000 to $3,500 price range offer shooters the ability to precisely tweak compression parameters. This leaves us, the more adept DV shooters of the world, in a terrible bind if we want to rigorously control image texture to achieve our storytelling goals.

Fortunately, the correct camera filter can go a long way toward helping the shooter achieve this necessary control. It can also help overcome one sobering and inescapable fact: that you spent only a few thousand dollars on a camera that is expected nevertheless to do the work of a less-compressed system costing 10 or 20 times more.

The Engineers' Notions

Breaking the DV Curse requires an understanding of the engineers' ideas that went into designing your camera. DV, like the other popular codecs ranging from JPEG to HD, utilizes a strategy known as discrete cosine transform (DCT).

DCT is predicated on certain engineers' notion of redundancy. Some of us can probably recall holding up a strip of film negative to check for a scratch or read an edge number. We may have noticed over any given stretch of film that one frame hardly seemed different from the next. In other words, there seemed to be a lot of redundancy from frame to frame.

Engineers also recognized substantial redundancy within a frame. In a typical winter scene, say on the East Coast, a seemingly uniform grey sky might cover a large portion of the frame. The sky is not really uniform, of course, but actually contains subtle variations in color and texture. But alas, this is the shooter speaking here, not the engineer.

And therein lies the problem: the shooter/artist versus the engineer. Sure, we all love engineers, and some of us even know them as friends. But the engineer has an entirely different obligation, namely to fulfill his duty to his employer and discard pixel data. This is his primary responsibility, and he is under intense pressure to jettison bits and reduce file size without the viewer or you noticing the missing details and nuances.

So engineers divided the DV frame into 8×8 pixel blocks that could be meticulously scrutinized. The 64 pixels inside each block are profiled in a process called “quantization” whereby pixels of roughly the same value are rounded off, declared “redundant,” and then discarded. Whoa. Now I'm feeling faint. Considering DV's high compression, this dogged search for redundancy is bound to lead to some less-than-satisfactory decisions.

But it gets worse. Based on decades-old assumptions, many engineers believe that humans inherently lack the ability to discern detail in shadows. So this is where engineers look to maximize compression. Oh God, no! This is why deep, impenetrable blacks are so characteristic of DV. Discarding shadow detail is the DV camera engineer's bread and butter.

On the other hand, as a shooter, I am paid, indeed I am judged, by my ability to retain subtle details in the shadows. After all, aren't shadows the essence of the great masters' brilliance and the basis of all visual storytelling? Retaining shadow detail is the shooter's bread and butter, and as a shooter/artiste extraordinaire I have a problem with engineers making such crucial decisions for me.

Different Cameras

It's curious that DV cameras should respond so differently to the same filter. Depending on size and density of a camera's chipset, the quality of the optics, and engineers' pre-conceived notions, what seems to work on one model camera may work poorly or not at all on another. The Black Pro-Mist filter, for one, produces highly variable results in DV cameras. This could be due to the microscopic dot-structure of the filter, which tends to throw some cameras' DSPs for a loop. Some models simply think the filter is “dirty” and try to correct for it! The result on screen is not pretty.

Before the digital age, the Black Pro-Mist filter was de rigeur for analog Betacam shooters. So were an assortment of low contrast, fog, and double fog filters that found ongoing acceptance by many film DPs. The double fogs in particular had virtually no relevance to DV — until now. The advent of the Panasonic AG-DVX100 and 24p production have dramatically changed the rules of the game for the DV craftsman.

The Tests

With the support of Tiffen, I recently evaluated five current DV models in the $3,000 to $4,000 price range: Sony's DSR-PD150 and VX-2000, the Canon XL1 S, the JVC GY-DV300, and Panasonic's AG-DVX100. All of these cameras are capable of producing excellent images. Of course, the trick is exercising the appropriate craft, which includes selecting the appropriate camera filter.

It's important to bear in mind that no single filter is appropriate all the time. A strong backlight, for example, tends to exaggerate a filter's diffusion effect, so a lower grade may be desirable under such circumstances. As with everything in life, good taste should be your guide. My recommendations for each camera model are based on my view of the world that camera filters ought not to be used in a heavy-handed way. The filter should be treated as a finishing touch, to give an image the correct patina for the story you're telling, like icing on a cake.

Virtually all genres of programming can benefit from the use of an appropriate filter. For DV interiors, a light tasteful diffusion is almost always desirable, even on documentary projects. For exteriors, camera diffusion is usually less critical, although shooters would be wise to monitor contrast and fine detail level to avoid compression and other artifacts.

Canon XL1 S

Despite improvements in the updated model, the DV Curse remains very much alive in the XL1 S. Shooters with this model should consider a camera filter of some sort an imperative. In the early stages of the DV revolution, this simply meant applying a Black Pro-Mist as a matter of course. Today, we know this is not the best choice for the XL1 S, as the Black Pro-Mist tends to produce a murky, unflattering look even at minimal 1/4 and 1/8 grades.

A better option for XL1 and XL1 S cameras is Tiffen's 1/2 Black Diffusion/FX. As I observed two years ago, the resultant image is tasteful and sharp. The diffused look is not at all obvious. This is an excellent filter for interior use with the XL1 S. For interviews it's a natural.

For exterior use, I recommend the 1/2 Soft/FX, although even at this weakest grade the effect may be a bit much for nonfiction applications. The Soft/FX produces a selectively diffused look with little or no loss of contrast, while the Black Diffusion/FX maintains sharpness along with the diffusion. For the DV shooter, that's an incredible combination!

One word of caution if you're considering the Black Diffusion/FX for your XL1 S (or other small-format DV camera). Like any filter or net with an embedded image pattern or etchings, the Black Diffusion/FX should not be used with the lens at the full wide-angle and stopped down beyond f4. In other words, you must maintain an f4 or larger aperture to prevent the filter element pattern from appearing on the screen. This can be especially problematic for exteriors.

Sony DSR-PD150

Compared to other 8-bit cameras in this price range, the Sony DSR-PD150 produces a more tasteful image — even before any diffusion is applied. The camera does exhibit a noticeable hue shift, however, particularly with bright red objects. A red rose, for example, might appear more orange, like a day lily, under high-key conditions.

Your choice of filter will do little to eliminate such camera defects, so shooters should understand the nature of such deficiencies and how they creep into the picture. Obviously, your filter can only do so much, and that is primarily to add a tasteful finishing touch. For PD150 shooters, the 1/8 Black Pro-Mist offers just such visual panache, and can be considered an excellent all-around filter for the DSR-PD150. While I don't generally recommend the heavier grade Pro-Mist and Black Pro-Mist filters for DV cameras, the slight diffusion and flare introduced by the 1/8 grade add a nice overall look in Sony models.

The 1/4 Black Diffusion/FX also performed well on my PD150 in a simple interior setup, but the 1/8 Black Pro-Mist may prove a more practical choice. The Black Pro-Mist, devoid of surface etchings, eliminates the risk of seeing an etched pattern on screen — a distinct advantage for “run-and-gun” type shooting projects.

For exteriors with the PD150, the 1/2 Soft/FX is the obvious choice for most projects. It's a solid performer, and offers the PD150 shooter the desired slight image softening with virtually no loss of contrast. For the DV shooter who must use a variety of camera models, there is probably no better all-around, general-purpose filter for exterior shooting.

Sony VX-2000

You might confuse the appearance of this consumer model with the more costly PD150, but you sure won't confuse the quality of its images. The punishing blacks and obvious presence of the DV Curse are not for the faint of heart. The VX-2000 is a camera that needs something — whether you opt for the Pro-Mist, Warm Pro-Mist, Black Pro-Mist, Black Diffusion/FX, or Soft/FX. One of these options is essential.

Panasonic’s AG-DVX100 is the first DV camera that performs well with filters originally intended for 16mm and 35mm film cameras. Gentle grades of these filters work best.

Compared to the DSR-PD150, the VX-2000 stands to benefit from increased filter strength. For example, the higher flare from the 1/4 Black Pro-Mist helps cut through the extra deep blacks. You'll have to put up with the resultant murkiness, but consider this the price for brightening the shadows.

Also, bear in mind that this camera naturally runs a bit cooler than either the PD150 or PD100A. For this reason, you may want to opt for the 1/8 or 1/4 Warm Pro-Mist. In interior setups, the filter's added warmth will significantly help skin tones, and thus the credibility of your subject (if that's your goal). Of course, as is the case with any warming filter, be sure to white balance your camera with the filter removed to avoid simply negating the filter's warming effect.

If you're seeking a more polished look for dramatic titles, the Black Diffusion/FX is an excellent choice. It adds a beautiful overall finish without the potential murkiness of the Black Pro-Mist. For exteriors, the Soft/FX will also work well on the VX-2000. However, you may want to select one grade up from my PD150 recommendations.

JVC GY-DV300

With its 12-bit processor and 410,000-pixel CCD, the JVC GY-DV300 exhibits markedly improved performance over earlier DV models, including the company's own DV500. Compared to that of the earlier generation, highlight detail is noticeably better in the DV300. It can be further refined via a series of user-selectable menu options useful for controlling critical compression parameters. These parameters include the valuable Black Stretch option to improve shadow detail, and a Soft Detail feature to prevent clipping.

Despite these advances, the DV300 also benefits from proper filter selection. The 1/2 Black Diffusion/FX adds a flattering touch to DV300 images, and it could be considered an excellent default filter for most interiors.

For portraits and interviews where a hint of grandeur (or glamour) is desired, the Gold Diffusion/FX filter is an absolute knockout. This is a very pretty filter with an incredible finish and professional gleam. In my evaluation, the 1/2 Gold Diffusion/FX is the filter of choice for current-generation 12-bit cameras like the GY-DV300.

However, I repeat my earlier warning to shooters employing such filters. The Diffusion/FX has a surface with a pronounced etched pattern that may become visible in strongly backlit scenes or when shooting with the lens stopped down. (Shooting stopped down is never a good idea anyway, due to lens performance issues.)

If visibility of the surface pattern is a concern, the 1/2 Soft/FX and 1/2 Warm Soft/FX are excellent alternatives to the Diffusion/FX. The Soft/FX is particularly effective outdoors, where shooters can shoot freely and unimpeded. The DV300 is a camera whose footage normally looks very good, but with the correct finishing filter it can look fantastic.

Panasonic AG-DVX100

With all the hype surrounding this breakthrough camera, it may be difficult for the curious shooter to separate fact from fiction. Let's just say the DVX100 represents a quantum leap forward in DV imaging. Shadow detail and lens performance are both exceptionally good, especially for a DV model in this price range. Like the DV300, some of this improvement may be attributable to the new 1/3in., 410,000-pixel CCD. Then again, part of the reason may simply be the better-than-average Leica optics and increased resolution afforded by the 24p scanning mode.

The integrated lens shade of some DV models, like the JVC GY-DV300, make mounting a professional matte box system difficult.

The DVX100 is the first DV camera that actually prefers filters originally intended for 16mm and 35mm film cameras. For vintage shooters like myself, who remember the good/bad old days, that's great news. I happen to have an Anvil case filled with fogs, double fogs, and Softnets. And guess what? These old filters (in the gentle grades) look great on the DVX100! Think 16mm — not 35mm — and you'll have a great handle on what works on this baby.

One word of caution to unimaginative shooters with a one-size-fits-all attitude. This is not a Black Pro-Mist kind of camera. The low-contrast and flare characteristic of the Black Pro-Mist will detract significantly from the inherent good looks of the Panasonic's footage.

For interviews and dramatic interiors, I liked Tiffen's venerable old Softnet 1B (a “black” net). This filter imparted an overall pleasing texture akin to something we might associate with a 1930s or 1940s period production. The Softnet 1S (“S” stands for skin) produces a comparable look, but with enhanced flesh tones — a clear choice when working with sensitive celebrities.

The Softnet seems like a throwback to vintage film shooters, but here it is again, very much alive on the DVX100. If you want a contemporary look, the Black Diffusion/FX is also an excellent choice. In particular, the 1/2 grade will produce a nice, flattering finish at 24p.

This brings me to my most enthusiastic recommendation: Ira Tiffen's little-known tour de force, the Gold Diffusion/FX. This filter in the 1/2 grade is the perfect complement to the new Panasonic camera, adding a nicely modeled, three-dimensional finish to interior scenes. Flesh tones in particular assume a special vibrancy that easily mimics the highest-end camera and format. If somehow we manage to fully break the DV Curse, ingenious filters like the Gold Diffusion/FX will undoubtedly be the reason why.

For exteriors, the DVX100 seems to prefer the #1 Soft/FX, a filter that offers a pleasant enhanced look without introducing flare or sacrificing contrast. Of course, the double fog has never been a real option for DV shooters, but it is again with the DVX100. Feature film DPs have used the double fog filter for years to add atmosphere to daylight scenes. On the DVX100, Tiffen's 1/8 Double Fog offers shooters a nice, tasteful alternative to the conservative Soft/FX.

Great Filters, But No Way to Mount Them

It happens that many current cameras, including the Panasonic and JVC, seem to ignore shooters' need to mount filters. These cameras may offer terrific performance, but the Panasonic model in particular offers no easy way to affix a professional matte box. The provided lens shade looks cool, but its open design is completely useless, negating the point of a lens shade in the first place. So you say remove the offending “shade” altogether? No problem. Its bizarre interface would seem to preclude mounting much of anything — except that lens shade. Grrr.

The JVC DV300 is no better in this regard, with a molded plastic front hood that also precludes a professional filter holder. Someday camera designers will make it a point to consult with shooters to avoid these kinds of issues. But for the moment, many DV shooters will have to resort to clumsy screw-in filters — not the ideal solution when working hastily under pressure or in harsh climates.

The Lesson in All This

Of course, it is possible to address the DV Curse without the benefit of an optical filter at all. The advanced menu options in some cameras permit shooters to change the look and feel of their images. But the gross settings typical of DV cameras affecting such parameters as shadow detail, gamma, and color matrixing generally do not allow the degree of control that shooters require and that clients increasingly demand.

It is also difficult to recreate the effect of a camera filter using software. In the real world, a camera filter affects images in a highly variable and often unpredictable way. Consider the complexity of ambient light striking the thousands of tiny “lenslets” in the Soft/FX filter. The character of the light — its color, direction, and intensity — will greatly influence the filter's effect as the light passes through and around the image elements in a delicate interplay. It's not a process that lends itself well to generalized solutions in software. Perhaps someday it will be possible — even with a $3,000 DV camera — but not right now.

The DV shooter today requires a range of filters appropriate for a specific camera. This is critical because the format can be cruel and unforgiving, requiring a shooter's constant vigilance. As more of our work is encoded for DVD, image control becomes even more critical as the blurring of DV's harsh lines is essential for good MPEG-2 compression.

So, dear shooters, with the correct camera filter, go forth and shoot. And may the DV Curse not be with you.

Camera/Tiffen filter recommendations

CAMERA	INTERIOR	EXTERIOR
Sony VX-2000	1/4 Warm Pro-Mist1	#1 Warm Soft/FX1
Sony DSR-PD100a*	1/8 Black Pro-Mist 1/4 Black Diffusion/FX2	1/2 Soft/FX
Sony DSR-PD150	1/8 Black Pro-Mist 1/4 Black Diffusion/FX2	1/2 Soft/FX
Canon XL1*	1/4 Black Diffusion/FX (Black Pro-Mist not recommended)	1/2 Soft/FX
Canon XL1 S	1/4 Black Diffusion/FX2 (Black Pro-Mist not recommended)	1/2 Soft/FX
JVC GY-DV300	1/2 Black Diffusion/FX2 1/2 Gold Diffusion/FX2	1/2 Soft/FX
JVC GY-DV500*	1/4 Warm Pro-Mist1 #1 Warm Black Diffusion/FX1,2 (nonfict.) #2 Warm Black Diffusion/FX1,2 (dramatic)	#1 Warm Soft/FX1
Panasonic AJ-215*	1/2 Warm Black Diffusion/FX1,2	1/2 Warm Soft/FX1
Panasonic AG-DVX100	1/2 Black Diffusion/FX2 1/2 Gold Diffusion/FX2 1B Softnet2 for period look	#1 Soft/FX (nonfiction) 1/8 Double Fog (dramatic)
*Indicates models previously discussed in Video Systems, December 2000.
1Integrates Tiffen “warming” filter #812. To prevent negating the effect of the warming filter, be sure to white balance with the filter off.
2Always be cautious when using any filter with an etched or embedded pattern, as such elements may appear on screen, especially when shooting stopped down or at wide-angle. Consider the Soft/FX as an alternative in such cases.

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For More Information

Tiffen
www.tiffen.com

B+W Schneider
www.schneideroptics.com/filters

Hoya Filters via The Filter Connection
www.2filter.com.

Cokin Filters
www.cokin.fr

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