Guide: Photographing 2D Artworks With A Digital Camera (Bridge or DSLR. Info Does Not Include Smart Phones)

17 May

(Most of the following work, writing and knowledge is not my own and I don't pretend that it is. It's a bullet point guide to help visualise what is needed when taking photographs of artwork. In all likelihood there are mistakes that need correcting. Do let me know if you see any below. Ax)

00 - Clothing

Wear all black or dark coloured long sleeved clothing. In the past I've been surprised when a white reflection that appeared in an image that I couldn't place turned out to be light reflecting off of my arm and t-shirt onto the painting I was trying to photograph.

01 - Initial Room Set Up - (If everything's perfect)

Need a large enough space to allow for a wide range of movement.
Remove as much clutter as possible from the space.
The perfect surrounding walls are covered in black paint or fabric. Can hang black fabric from ceiling and cut a hole to allow camera lens and sensors to poke through if changing the walls is not an option.
The wall’s behind the artwork needs to be in a neutral colour - white to mid-grey, at a push black will work. Strongly coloured rooms can create colour tinting which may not easily be remedied outside of any post production work.
All room lighting is switched off, doors closed and windows blacked out/covered.
All metallic objects/ surfaces need to be covered in black fabric, black electrical tape or removed to stop unwanted reflections and glare.
Take photos at night as this will decrease the likelihood of unwanted external light causing problems.

02 - Placing Artwork

Make sure the wall is truly vertical, if not you may need to compensate (angle the camera so it's perpendicular to the surface) or find an easel to place the work on.
Place artwork at a height that is comfortable to work around.
Make sure the art work's top is horizontal and its sides are vertical with a spirit level.
Secure artwork on the wall in a way that wont be visible within the shot unless it's needed to be seen.
Measure the mid-point of the work to the ground. Note this down as this is the height the centre of the camera's lens will need to be off of the floor.

03 - Camera Settings

Set the camera's settings to manual (M).
Set ISO to 100 (or lowest possible ISO setting) the lower the setting the sharper the quality of the image and less noise intrudes.
Set f-stop to f8 it allows for a relatively good depth of field ( f-stop can be between f10 and f6 depending on camera used. Too high an f-stop setting can impact negatively on shutter speed and diffraction blur can impact on sharpness. Too low an f-stop and the depth of field will be too shallow and the outside corners of the painting may fail to be in focus) .
Set camera pixel resolution to highest setting for camera.
Set camera to shoot in RAW files... (when converting photo to JPEG within camera a lot of information is lost which RAW files keep)
Set 'sharpness' to 'standard' setting.
Switch off all the camera's extra "bells and whistles" as these can introduce unwanted visual artifacts into the photograph.
Use a 50mm lens or greater (up to 80mm) . Smaller lenses will introduce 'barrelling' which can't be fixed easily outside of the likes of Photoshop. Fixed lenses are better than zoom lenses as there is less glass internally than a compound zoom lens, so less blurring and distortions appear within the resulting shot.
Use a remote shutter release cable, wifi/ blue tooth remote shutter release, or set the camera's shutter timer to auto-release at 10 seconds to help avoid any camera shake made by touching the camera's shutter release button.
If using batteries make sure they are charged up and that replacements are available if needed.

04 - Tripod

Make sure the camera is attached securely to the tripod
Raise the tripod so the camera lens is at the measured midpoint of the painting
Make sure the camera is leveled horizontally and is vertically in line with the painting, you want it to be perpendicular to the plane of the painting
Move the camera both away and towards the artwork until the view screen frame is filled with the painting as much as possible without distortion.
Be aware of any distortions.(see below)

Note: this diagram below of 'key stoning' helps to show what to expect when the camera is not positioned correctly. The arrows point in the direction the camera needs to move to correct the distortion problem.

Note: If 'barrelling' occurs (see image below) this suggests too small a lens is being used and/or the camera is too near the artwork. Make sure the camera lens is 50mm or more if possible (up to 80mm), then try moving the camera away from the art work. When happy try making the artwork fill as much of the camera's viewing frame as possible. There may be slight barrelling that occurs naturally (especially with zoom lenses) which will need to be sorted post-production in the likes of Photoshop.

05 - Lighting

The lights should be placed at a 45° angle (or greater) with respect to the camera (so each light is separated by an angle of > 90° (greater than 90 degrees) . Very obtusely-angled lighting is referred to as “raking light'. It’s great not only for avoiding glare, since the angles are so extreme that they are often outside the family of angles for reflection, but also for showing texture if a painting's surface is a feature that needs to be highlighted), and half way between the art and the camera, this will give an even, diffused light

Type of lights - led, tungsten, halogen, etc. - I'm not going to go into the specifics but LED seems to be winning out in all that I am looking as it's comparatively low in energy usage, and low in heat emission, with a controlled and stable light yield. Obviously the brighter the light the better but brightness can be compensated for by lengthening shutter speed for less bright sources. Several seconds shutter speed is to be expected.

Recommended colour/ light temperature in kelvin - daylight (4000-5000k),
Colour balancing is not as much of a problem as it used to be. Using 'custom white balance' correction within camera will sort things out as will knowing the type of lighting or the colour temperature of the lighting being used which can be manually selected in the camera.

What's better, light boxes or lights that are being diffused and reflected by or through umbrellas? Thankfully this following article answers this question. ^[*17] - "A Guide to Choosing Umbrellas and Softboxes" (which has confirmed for me that soft boxes are correct to go with. Umbrellas have a tendency to bounce light all around a room whereas soft boxes are a lot more focused. The light is also a lot more diffused and in turn even as it is coming from soft boxes that often have a double layer baffle, whereas umbrellas can have hot spots over an umbrella's surface which provide an uneven light).

Placement of reflectors (2 sheets of foam board) bounces light so to fill areas that are lacking.

Needing a cheap option to bounce light around? Use large sheets of white polystyrene insulation sheeting to help reflect light over any dark spots on the work. Hold the sheets, pin, suspend or clamp near the top and/or near the underneath of the work.

A more professional option are reflectors that can be bought from any photographic equipment merchant (eg this white grey, mirrored, silvered, and gold reflector)

06 - Glare Appearing On Paintings? Correct By Using Polarised Filters and Gels

Polarising filter gel sheeting to place over the front of light-boxes - (example of sheeting on EBay) The important thing is making sure the gels are not too close to the lights, which can warp or melt them, and that the polarisation lines etched onto the surface of the gels are aligned in the same direction in the front of both lights.

This is easy to check by simply holding one gel over the other one and rotating them. When they become transparent, they are aligned; when they turn black, they are out of alignment.

A 'linear' polarising filter for over the lens (note it's not a 'circular polarising filter', this matters hugely. It's specifically linear so to marry with the linear polarising nature of the gels) (example of a filter on Amazon)

Look through your viewfinder and rotate the polarising filter on the front of the camera lens until you see the painting darken slightly and the glare magically vanish!

If you are having difficulty seeing exactly when the glare disappears, move the camera closer to the painting to adjust the lens filter. Once the filter is adjusted properly, you won’t have to change this setting when you move back or shoot additional paintings.

(Showing how glare can be substantially reduced using a linear polarising filter lens and polarising gel sheeting)

This following Youtube video ^[*19] is a perfect example of just how much glare can be removed by the use of polarising film and a lens filter

07 - How to Adjust 'Custom White Balance' Settings
Using 'White, Black & Grey Colour Cards' Or 'The Passport Checker'

The Digital Black/White/Grey Colour Balance Cards

Interesting note: the grey is not a 50% ratio of white to black it's 18% grey (favouring white). It's the setting that a camera is registered to search for when finding a neutral colour to automatically adjust white balance). Don't use 'auto white balance' use the 'custom white balance' setting when colour correcting in camera.

A grey card is also useful if you are having problems getting the correct exposure settings, for example - if the object being photographed is too light or too dark and the camera's light meter reading suggests an incorrect exposure setting. Video^[*22]

It's in post production when both the black and white cards become very useful. After taking a photo of the desired image take one extra shot with the 3 cards in front and this will help in setting base points for white, black and greys in the Photoshop filter 'curves'. Also see - https://en.wikipedia.org/wiki/Gray_card.

'The Colour Passport Checker'

The following video ^[*23] is a thorough introduction in how to use this little bit of kit for colour correction and light balance during a shoot and in post production.

08 - Take The Photo

Clean the camera lens and filter with a lens cleaning cloth
Focus your image (manually or with auto focus). If having problems with focusing place a sheet of newspaper directly in front of the work this will help give your camera something with clear edges to focus upon.
When setting focus aim at around 1/3rd of of the way in from the outside edge. When focusing it's good to be aware that with depth of field what will be in focus in front of that point will be the central 1/3rd of the painting and behind will be the outside 2/3rds
Now's the point to set exposure / shutter speed. Change the shutter speed to an appropriate setting. When happy take 3 shots, one shot at ideal speed then one setting either side (1 stop slower and one stop faster) this allows for corrections of any problems that can't be perceived until involved in post-production processing. (Remember to place the Colour passport or the black/white and grey card in front of the artwork for that extra shot for post production)
I have also learnt a new trick to make the resolution of the photograph of the painting in post processing to be even more detailed and sharp. "Image averaging". Take 5 photos with exactly the same settings, then in post processing average out the noisy differences. See the following YouTube video for more information"Better Than HDR? Try Image Averaging for Better Results"