A little while ago I was talking with a friend about the best way to photograph some greeting cards she had in her craft shop and wished to display on her website for potential online sales. I thought it might be useful to document the essential points.
I'm assuming the minimum of photographic gear and use of a smartphone to take (and perhaps edit) the pix.
I've listed here the important things to consider, and will expand upon them below :
- Even lighting
- Camera and card positioning
- Flat, parallel subject and camera planes
- Correct colour balance
- Correct focus
- Correct exposure
- Minimise blur due to camera movement ('camera shake')
- For maximum quality use manual settings if available
- Edit and crop
If we stick to the idea of keeping this as simple as possible then we should consider daylight first. A North facing window is best, with a table or other flat surface illuminated by its light. You can use artificial light, which comes into its own for larger artwork and consistent lighting across a large number of items that you want to present together as a set. For now we'll stick to using daylight for greeting cards.
The light should be from the side at a narrow angle to minimise reflections, especially for cellophane wrapped cards. In the pix here of the card you can see the bright spectral reflections on the right edge of the cellophane wrapper. The directionality of the light reveals the texture of the card and helps highlight the recessed colour detail in the die cut hole. See also the expsoure section for more discusion of the light fall off across the card.
Do not use the built in camera-phone flash or LED light. For cellophane wrapped cards you will have all sort of issues with reflections and hot spots.
I'd suggest laying the card flat on the table, with the camera-phone just far enough above it to fill as much of the frame as possible. If the card keeps opening then use a small piece of masking tape folded back on itself to stick the front and back of the card together. The important thing is to get the front of the card as flat as possible.
Keep it on the square
This is one of the most crucial bits when photographing two dimensional subjects like cards. First ensure the centre of the card is immediately beneath the lens on the camera-phone that will take the picture. You might want to double check exactly where the lens is, especially in these days of multi-lens camera-phones. the 'standard' lens is your best bet. The tele-lens will probably not include all the card whilst the wide lens might introduce bending of the card edges.
To minimise distortions the horizontal plane of the camera-phone needs to be perfectly level. If the camera-phone is titled to one side or its top or bottom is nearer the table than the other end then we get what's called keystone distortion. Just like when you tilt your camera-phone up to try and take in all of a tall building. Here's an example. I've added the red box better to see the convergence of the sides.
Example of keystone distortion due to tilted camera. The top of the card appears narrower than the base.
The easiest way to ensure your camera-phone is level is to use a pseudo spirit-level app. Here's an example.
Example Bubble Level app for android phones.
I'd strongly recommend some sort of baby tripod or support and a bracket designed to hold a phone as illustrated below. This is particularly useful when doing a series of cards as you can easily replace one with the next, line it up and continue shooting.
GorillaPod table top tripod with phone grip, set up on a table.
If you have the gridlines showing too in the camera app it will help with alignment of the card edges.
In photographic circles this is also known as White Balance. It means that the camera-phone sensor is registering greys and white correctly. The reason it might not is down to the light source. If we stick to our simple daylight scenario then the presence or absence of cloud, the time of day and the angle of the sun can all produce different coloured light. It could be too red or too blue, 'warm' or 'cool' as we say. Most camera-phones set this automatically like other, exposure related, settings. Some camera apps have a manual control setting, if so then you can most likely set the white balance here. You may see values such as 3400K or 5500K, these are degrees Kelvin. You can read more about colour temperature by searching on line or peruse the carton of an LED light bulb.
Remember that with virtually all camera-phones you can choose what to focus on by touching it on the screen. This is not so important when photographing a card because it is all in the same plane (i.e. flat). However, it is more important for exposure, as we discuss in the next point. Most camera apps make a good job of focusing, but depending upon phone to card distance it might be helpful to activate the macro setting.
Touch the phone screen over the most important detail of your card to base exposure on that area, rather than an empty white area. 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 nudge the exposure up a tad.
There may be a very slight difference in exposure between the edge of the card nearer the window and the further one. Move the whole set up away from the window to reduce this effect (go research the inverse square law if you want to find out more). If it's still very noticeable then use a piece of white paper or card on the opposite side from the window as a reflector to bounce light back and even up the exposure. Be careful the reflector does not create its own set of reflections in the cellophane wrapper. Adjust the angle of the reflector to minimise this.
The blur I'm thinking of here is not the same as not focusing properly. It refers to camera-phone movement (AKA camera shake), most likely when you are hand holding, which leads me to re-emphasise the recommendation to use a table top tripod and bracket. Even with a supported camera-phone you could still get movement by nudging the camera-phone when pressing the 'shutter button' 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.
Quality Product Summary
Full control of your camera-phone settings will give you the best quality results. This means setting the lowest possible ISO value, setting white balance manually and fully controlling exposure. You can also ensure that your flash is turned off (it will most likely produce hot spots in your photo, especially when the card is wrapped in a transparent cover). The screen capture below shows an example of the 'pro' settings you can expect in a modern camera app. Key things to note are: the ability to capture Raw files, the self timer set to three seconds, a low ISO value (100) for lowest noise (noise = grainy pix), White Balance (WB) adjustment and manual control of the shutter speed (here 1/100th of a second). The Gridlines are also shown which can be of great assistance in aligning the sides and/or top/bottom edges of the card with the image frame to minimise distortion.
Typical 'Pro' settings in camera-phone app
Use a tripod, ensure card and camera are aligned, set focus, take photo with the self timer to minimise vibrations.
Fix it in post
Use an editing app such as snapseed to make any post processing tweaks, such as cropping the image. It is also possible to alter exposure and white balance settings here and if you've really stuffed up, even minimise keystone perspective distortions. You can also use it to remove marks or imperfections, such as the dirty mark two thirds of the way down on the right hand edge of the card wrapper, visible in the final product image below. Generally however, it's better to attend to such things when taking the photo, but we all miss things.
The snapseed tools menu, only hinting at the power beneath.
Perspective correction, exposure control, white balance adjustments, cropping etc.
The final image, taken on a OnePlus 7T camera-phone and tweaked in Snapseed.