SpyderCube – Essential On-Set Tool

My favorite white balance tool is by far the SpyderCube from DataColor. This little tool is always in my camera bag, and I find it invaluable on set, not only as a simple white balance reference, but as a lighting ratio reference, as well as a black point reference. DataColor has envisioned this tool as a complete post processing control reference and has a set of instructions for its use on the SpyderBlog , but I don’t follow all their suggestions in my own workflow – I will explain how I use the SpyderCube in the following…

The SyperCube is a small 1.5 in. cube, with neutral gray, black, and gray/white sides. There is a polished metal ball with a string loop at the top, so you can hang it off things (it makes a great Christmas ornament,) and a threaded socket on the bottom so it can be attached to a tripod or light stand – or fastened to the SpyderChecker target, as shown in this photo. There is also a small hole in one of the black faces that is a light trap that acts as an absolute black reference. The genius of this device is that you have a good reference for 8 different values for calibration or lighting purposes; key light gray, white and black, fill light gray, white and black, specular white, and absolute black. In the photo above the cube has been oriented so that one gray/white face is receiving the main light source, in this case a small softbox, the other gray/white face is receiving the fill light in the form of a pop-up reflector. In practice you can use the gray side as a white balance reference for your raw processing, but it can also be used for exposure control, as it is an 18% gray. * ( you could use a spot meter to measure the value from the lit gray side and set your exposure accordingly) The idea is to place the SpyderCube in the same light as your subject and take a photo – the polished ball will always show you the light source in a specular reflection – you can count the number of sources easily. In very controlled situations where you are placing the lights, this may not seem like a big issue, but where the SpyderCube really becomes helpful is in uncontrolled lighting situations.

On a recent assignment, I was charged with taking photos and video for a Jazz album recording project for Joeseph Tawadros’ up coming album. This was a real gorilla shooting assignment – no, or little control over lighting – though I did bring some Micro Lightpanels for supplemental lighting, most of the light was low level tungsten lighting inside the recording studio. I shot stills and video at 3200-6400 iso, the whole time! The recording studio had multiple light sources, mostly varying tungsten color temperatures from a low close to 2000k, to something closer to 3200k, plus a few cooler lights coming from various monitors, computer screens, etc… Overall, however the lighting was a pretty consistent intensity – this turned out to be a good thing because I never had time to set lights or make any real adjustments on the fly. I set the SpyderCube down on one of the tables near where the musicians were working and banged off a shot…

This is not an ideal placement because the wood table surface is reflecting into the shadow reference and that will affect the color balance there, but the absolute black is so dark that the reflection has no effect. Though I had my Sekonic light meter with me, and I could have taken a spot reading off the SpyderCube, most of my actual shots were going to be musicians dressed in dark clothing with a lot of shadows – I had to rely on my camera meter for the quick grab shots I had to capture and I was going to be cheating the exposure up a bit. If you zoom in on the camera back you can look at the little ball to see the various light sources affecting the scene…

I can see 4 main light sources with two different color temperatures at a glance. This can indicate that I might have a problem with shadows possibly being a different color than highlights due to the different directions of light. You can perhaps notice, in the previous full image of the cube, that the filled side has a warmer color – I white balanced off the lit side of the cube in Lightroom – on set this wasn’t obvious at all, nor did I have the opportunity to do anything about it. After a quick check, I realized that I would have to fix most issues in post!

This is a fairly typical shot from the recording sessions:

You’ll notice there is a lot of dark shadows that need detail – often there was some area in the shot that was more brightly lit, and so the dynamic range of the shot is such that its hard to favor the shadows completely – in this case, the control room is clearly visible behind them and it contributes to the story of the photo. Most of the time I was also shooting video and, after doing a custom white balance in-camera, I pretty much had to stick with one setting for everything and try to get a decent overall exposure within the frame. For the video, I used a slightly blue white balance card to cheat the white balance a little warmer – this is a common trick for video to prevent the footage from looking too cold. This also had a slight benefit for the high iso – my camera, a Cannon 5D mk II, has a tendency to go blue in the shadows at the highest ISO.

The SypderCube proved to be very helpful in rough calibrating the color shift in the shadows…

Even after using enough color noise reduction to to even out the color and suppress, just enough noise:

The RGB values for the deepest blacks are showing a purple bias! R=4.3, G=1.9, B=13.3

This purple bias is only present in the darkest shadow values, but it is in every shot in this case because everything was shot at the highest ISO settings! I needed a way to quickly determine the lowest shadow value and somehow neutralize that across multiple images – this looks like a job for the SpyderCube. Datacolor recommends using the Black slider in Lightroom  to clip the light trap hole to the black point – of course the black point in Lightroom indicated by the clipping indicators is zero. I never want to end up with a zero black point because that would guarantee that I’d lose important shadow detail in a print. Instead, I’d like to make the lowest value neutral without shifting the mid-tone neutral around. The SpyderCube easily locates the darkest point in the camera image – it will be in the light trap hole!

This value is lower than the first black example given above because here I can find the absolute darkest thing easily, without using clipping indicators to locate some area in a regular image! Now I want to get this point to be as neutral as possible and apply that to all the images from the session. The key is to adjust a little used slider in the Camera Calibration Panel…

I usually find that I have to re-do the white balance after adjusting the “Shadows” slider here – kind of bouncing back and forth until I find the best setting. I can almost never get a perfectly neutral black value, but I can definitely take the curse off enough that I get a good improvement in the captured images. You can see above that R & G are almost equal to each other and the B value has come down to striking distance of R & G – you can just barely see it visually in the dark face of the SpyderCube as well. Syncing this new “Calibration” with the rest of the shots, and going back to our black example from before…

We can see a big improvement in the shadow value “numbers”. While not perfect, this is certainly good enough for client evaluation and approval purposes. When selects are made I can further refine the black point adjustments in Photoshop with a simple curve or, for more serious shifts, use the technique I outlined in my post: “How to Desaturate Shadows in Photoshop, for 3D Contrast” The SpyperCube comes in handy for this as well – I’ll go through the steps using the SpyderCube below…

Process the adjusted SpyderCube shot into Photoshop…

From the bottom of the Layers panel, select “Solid Color ” from the Adjustment Layer icon menu…

I the resulting Color Picker dialog, select a neutral gray color – make sure R=G=B!

When the adjustment is in place, it will cover up the image. We will use “Blending Options” to control where the gray color is applied. Select “Blending Options” from the layer options fly-away menu at the upper right corner of the Layers panel…

In the resulting Layer Style dialog, drag the white triangle slider, in the “Underlying Layer,” to the left until you are only covering up the light trap hole of the SpyderCube…

Split the white slider triangle into two halves by option/alt dragging the triangle apart – pull the right half to the right until some of the gray blends smoothly into the dark face of the SpyderCube…

Change the layer blend mode to “Color” in the Blend Mode menu…

The beauty of this technique is that it insures black point neutrality without messing with the rest of the image. You can record an action based on the setting derived from the SpyderCube and apply it to multiple images from the shoot, or simply drag the blended adjustment from the SpyderCube image onto any other image in Photoshop.

Here are a few more images for the shoot, all shot at iso 6400…

So… I find the SpyderCube especially useful in these sort of situations to help speed up my workflow. This modest little device provides a lot of really valuable feedback on set and in post. Datacolor seems to really have the photographer in mind with a lot of their products, and its well worth checking out the SpyderLENSCAL, SpyderPRINT, SpyderCheckr, and the Spyder4 monitor calibrator…