Last time we looked at taking a close up photo of a flat subject, in that instance it was a greeting card. Now we expand into 3D, but still apply the cheap and cheerful approach. Here is our subject, he stands 68mm tall. We use window light, some bits of white card and a pedal bin bag...
Figure 1 :: The final product.
As before here is a list of the key things we need to consider.
- Background and setup
- Camera positioning
- Lighting, shadows and reflections
- Correct colour balance
- Correct focus
- Correct exposure
- Minimise blur due to camera movement ('camera shake')
- Shoot RAW for maximum quality
- Edit and crop
Background
Keep it simple usually works best. A simple white background gives a minimum of distractions from your subject. The key points are to make it seamless and free of distracting detail and consistently and evenly white. Figure four lower down shows the effect of a textured background (in this case I was trialling unwound kitchen roll). One way to achieve the seamless look is to use an 'infinity cove' (or curve). Figure two shows one of the set ups I tried that shows the infinity cove/curve from the side.
Figure 2 :: infinity cove in profile.
This is using an A4 sheet of heavy white paper taped to a box at the top and another sheet of white A4 beneath. If you get things better aligned than I did then you can have the box sitting on the lower sheet too so that the whole thing can be slide around and rotated on the table to try different angles to the window. Using a longer sheet of paper with more horizontal expanse before beginning the bend upwards makes it easier to keep stray shadows to a minimum.
The pile of books are there to provide additional height to the whole thing if you have a table top tripod that will not go low enough, I also experimented with the tripod and camera-phone on a stool, as you can see from other pix. This worked best in minimising a shadow from the camera-phone itself onto the subject.
Figure 3 :: Camera-phone and GorillaPod on a stool for lower angle.
Camera position
The angle of the phone to the subject is very important. it will have a significant effect on how the subject appears.
Figure 4 :: Foreshortened subject due to angle.
In Figure four from a higher camera-phone angle the subject appears to be foreshortened. Incidentally you can also see the textured, non-seamless background and uneven lighting from left to right in this example.
Light and dark and shiny
Too much light and you lose detail in the lighter tones of the subject. Too little light and you not only lose detail in the darker shadowy parts but your white background will start to go grey as well. With a glossy, shinny subject you often get to see lots of stray reflections of your window, bits of gear and sometimes even yourself.
Figure 5 :: Shiny reflections should be avoided or minimised at least.
Figure five taken with the window light coming in directly from camera-left shows the issue of glare and stray reflections along the subject's right side and as vertical bands along the front surface. You can see the setup in figure six, in which my assistant is making some last minute adjustments to the camera-phone position, with his head...
Figure 6 :: Window sill setup with assistant.
Other things to note here are that the camera-phone is upside down and is balanced by the GorillaPod resting two of its legs against the window. This was to get the lens as low as possible and level with the subject. I am using the pedal-bin liner, split open for maximum surface area, as a diffuser for the light. As you might infer from Figure five, it's not doing a great job in that particular location.
On camera right is a piece of folded card acting as a reflector. You can also see two of them in Figure three. In a studio setting they are called V flats and are typically at least two metres tall. Both the full size and table top versions as seen here are great for moving around your subject to bounce light into the shadows. You can also use black folded card as a flag to diminish light reflections and enhance a shadow, for improved modeling and shaping.
This window sill type of arrangement is worth trying out but I decided that the ergonomics of the layout, directionality of the light from camera-left and precarious balance of the phone was a bit too troublesome to pursue.
To minimise discernable reflections in bright shiny parts of your subject it is best to provide as large as possible diffused light source, wrapped around the camera-phone position. To create this I was using the split pedal-bin liner, stretched over and taped to a support, in this case ironically the arm of an anglepoise type lamp. You can see some of it in Figure seven. Double up for even more diffusion. Also, the larger the diffused light source in relation to the subject, the softer the shadows will be.
Figure 7 :: Top view of set up with diffused light source.
Colour or White Balance
The fidelity of colours for art and craft subjects is likely to be very important. That is why getting the White Balance correct is critical. Figures eight and nine are examples of what things will look like when the white balance is set incorrectly.
Figure 8 :: White balance set to 3400K (degrees Kelvin).
In Figure eight the white balance has been set too low, resulting in an image that is too blue and cool.
Figure 9:: White balance set to 6900K .
In figure nine the white Balance is too high at 6900K, resulting in a warmer, slightly red image. As an aside it should be noted that in non-colour critical work it is not uncommon to tweak the White Balance away from the 'correct' value to achieve a pleasing effect.
Experiment with the auto White Balance on your camera-phone to see how accurate it is. If necessary learn how to change the camera app to manual in order to fine tune the White Balance.
Focus
Touch the phone screen over the part of the subject upon which you want to focus. In this example it was the face of the cat. If you forget to do this the camera app will guess what you want to be in focus. It will often be right, but it is best not to leave it to the vagaries of an algorithm.
Exposure
Having touched the phone screen to identify the point of focus most camera apps will then let you slide your finger up and down the screen to increase or decrease exposure. Slight adjustments might be useful to compensate for the guesswork your camera-phone is doing, especially if there are large expanses of white card. If the white bits are looking a bit grey (i.e. under-exposed) then slide your finger to raise the exposure.
Keep it sharp
As I said in the previous blog item. Even with a supported camera-phone you could still get movement by nudging the camera-phone when pressing the 'shutter release' on screen. Eliminate the chance of this by setting the self timer in your camera app to a short interval like three or five seconds. This will allow vibrations from contact with the camera-phone to die away before the picture is taken.
RAW quality
The best quality image from your camera-phone app will be of type Raw. This will often be the default setting when you switch the app to manual or 'Pro' mode. The file type may be proprietary to your make of phone but is more likely to be a .DNG file, which is Adobe's Digital Negative Raw Image file type. This can be opened by all popular editing software and phone apps such as Snapseed. It cannot however, be uploaded directly for inclusion in websites, where .JPG and . PNG are the standards. i recommend you use this format for the highest possible quality, if you want to do any subsequent editing of images, then save or export to a .JPG file.
Editing
In an app such as Snapseed you can crop your image just as you want it (to remove the masking tape holding down the edges of the infinity curve card for example), make slight adjustments to exposure, contrast and detail sharpness and even change the White Balance if you didn't get it right at the taking stage.
