Photography

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A Picture taken on fully automatic under tungsten light, notice the orange tinge to the picture and the fact that it is also underexposed (i.e. too dark) this is a common problem with all cameras
This picture is now taken with the white balance set to manual in the camera by setting it from a grey card, notice the fact that although the picture is still underexposed the white paper is now grey rather than orange

Photography is an entire subject that could take up a whole Wiki all by itself. What follows here are some hints and tips for beadmakers wishing to get good photographs of their beads or glass work.

It is generally regarded that the better your original image (off the camera) the better the final result will be. Yes you can adjust pictures in Photoshop afterwards but the final quality of the image will suffer (see final pictures). For the best image quality you should aim for an image that is as close to how you would like it before it even touches Photoshop. Then all you need to do in there is a bit of sharpening (perhaps) cropping and maybe adding a watermark.

Contents

Problems with glass

Generally speaking glass is actually quite a difficult subject to photograph due to its reflective nature, but given a few simple tips a bit of patience and some quite simple equipment it is possible to get very good results.

Basic Set-up

The same as above, but now with one stop of exposure compensation added. Notice that the white paper is still a slight shade of grey...we still need a bit more compensation
The same as above, but now with two stop of exposure compensation added. Notice that the white paper is now much closer to white, but interestingly now has a slight pink tinge. This is because the camera is not adjusting correctly for the white balance of the light as the exposure has changed.

The basic set-up required to photograph beads is actually very simple.

  • A light source (desk light or window).
  • White piece of paper.
  • A Digital Camera.
  • Tripod (if you have shaky hands, or not much light, or both)
  • Oh yes and some glass work to photograph.

You do not really need more than this to take basic good quality photographs of your work.

When taking pictures with this type of equipment it is important to set up the camera correctly to get the best shot, because if you just turn your camera on and take a picture you will generally be very disappointed with the result.

Just to make a point, all the pictures on this page were taken with no more than a white piece of card (balanced on a clothes airer) under a halogen ceiling spotlight. (OK the camera was a Canon EOS 20D but I could have (and have) got very similar results with a point and shoot camera, as long as it has white balance and exposure compensation adjustment)

There are two setting that are very important that you understand to be able to take good bead photographs.

  • White Balance
  • Exposure Compensation

White balance

What is white?

As many of you may know there are many types of white, our eyes are very good at compensating for different light colours and different shades of white, and we just know that something is white. Cameras on the other hand are dumb, and have to be told what white is, otherwise they will get it wrong. Therefore the white balance setting in a camera is to make sure white is actually a white and not yellowy orange or blue.

Most cameras do this automatically when you take pictures, but quite often get it wrong, especially if there is a lot of one colour in the scene. Higher end cameras will often allow you to take a picture of something grey or white and set the cameras white balance from that picture, many low end cameras often have this feature as well, so it is well worth checking your user manual for "Manual white balance".

If your camera does not have a manual white balance setting then what you must do instead is set the white balance to match the lighting conditions. Although auto mode is OK. It often gets things wrong, but if you are taking pictures with tungsten lights then set to tungsten. etc. Remember that direct sunlight is a different setting from shade, even though the light is coming from the same source. Shade is actually very blue in colour, so you should ensure that your camera is set to the correct setting.

White or grey?

In real life, due to the nature of white not always being pure white I would thoroughly recommend buying a grey card from the likes of Jessops. This is calibrated to be a mid grey (often called 18% grey card) and is ideal for setting the white balance and also for getting the correct exposure as the brightness of the card is also calibrated. But if you do not have one don't worry a piece of the whitest paper you can find will be fine.

Despite the fact that white balance makes sure that white is white it should not be confused with

Exposure Compensation

This ensures that white is white and not grey!!!

Basically this setting allows you to over/under expose your pictures, that may sound wrong but the reason you would need this is because all cameras have to work out the correct exposure for a given scene.

The problem comes when what you are photographing is a picture of a bead on a white piece of paper and this is certainly not typical, and the camera will under expose it. (as wrong as it might seem this is the correct behaviour as most scenes that you photograph will average out to a mid grey in terms of brightness).

Many people think that under exposed pictures like the ones shown on the right are due to not having enough light, but that is wrong, adding more lights will not solve this problem. To correct this you need to "fool" the camera into over exposing the image so that white paper actually looks white and not grey. (remember this is not to be confused with white balance as described above)

By changing the exposure compensation to add 1 or 2 stops, that picture of a bead on a white piece of paper will be white and not grey and the colours in you beads will be much more vibrant, thus removing the necessity to process all your pictures in Photoshop.

Results

The final version that has been slightly adjusted in a photo editor, to remove the slight colour cast, and brightened just a little bit
This is the original under exposed and incorrect white balance version of the photo, but corrected in a photo editor. This is as close as I could get it to the right look. Notice though that the colour is not as vibrant as the picture above and that the shadows have a slight orange tinge. The picture is also more grainy. Although this may be acceptable to you the correct version is far superior.

You can see the results of these above techniques in the last photograph in the series above, but I personally would tweak them a little bit in Photoshop (see the two photographs on the right).

The final two pictures are quite similar but the first one is a very slightly corrected version of the best shot from the series, this was just to correct the small amount of colour cast that was there and to brighten it just a bit more, this is because +2 stops was not quite enough, but my camera only allowed me to add 2 stops. I could have used manual mode to get it spot on, but we will go into that later.

Note that it is possible to get the pictures even better from the camera, but beware that if you push the exposure too far, then you are in danger of burning out the image, and you will then loose highlights (which you will not be able to get back). It's much better the leave a bit of headroom in the image and then adjust out that little bit in Photoshop as you are in complete control over the amount you can change the exposure by.

To show the difference in getting the picture right first time the final picture on the right is a photoshopped version of the very first badly underexposed and incorrect white balance picture at the top of this page.

Although this may not look too bad, the colour vibrancy and accuracy of the colours to the original beads is not as good, also the grain of the camera's sensor is also visible and detracts from the image. Basically the picture is just not as sharp or as crisp, especially when viewed large or printed.

Remember to click on the images to see larger versions...

Manual Exposure

If your camera has a full manual mode (i.e. allows you to set both shutter speed and aperture together and separately then this is the way to go.)

If you don't have a grey card (as described above) and you want to get a good approximation for 18% grey for metering you can do a lot worse than using the back of your hand....(assuming you are a white skinned Caucasian that is) I'll tell you how to do this, but I would suggest getting a grey card anyway, they are also useful for white balance as described above and don't cost very much...

Basically, set up your photo studio lighting as usual. Set your camera to full auto mode then fill the frame with your hand and take a picture of the back of your hand (in the same position as the bead would be), remember try to ensure that as much of your hand fills the fame as possible, don't bring your hand closer to the camera than the bead will be, so that the lighting is the same as it would be for the bead picture, so zoom in with the camera to the level that you would want to photograph anyway.

Now note down the shutter speed and aperture values that your camera decided to use to take this shot. (for example 125th second at f5.6)

Now, change your camera to manual mode and dial in the same settings as those noted above. Now any pictures you take should be exposed correctly for the scene, assuming the lighting does not change that is.

Don't worry, the camera will probably be desperately trying to tell you the picture will be over exposed... but don't believe it... It's lying... honest (after all what does it know, it's only a camera, it isn't as educated as you in glass bead photography)

And that's it... if you do have a grey card (and again I strongly suggest you do) then you do exactly the same thing as above but replace your hand with the grey card... well... keep your hand attached to your wrist, just put the card in front of your camera where you hand once was. (I think you understand!)

The grey card's usage is not just restricted to setting the exposure while taking pictures, It is sometimes also very useful to leave a bit of the grey card visible in the corner of a shot so that when you come to crop and edit your shots later you can double check both the white balance and the exposure in Photoshop as the grey card should read at mid point grey in Photoshop and with an even white balance. You can click it with the eye dropper tool to select the white balance setting and all three of the red green and blue values should be 127.

Technical bit - Why can't I just edit in Photoshop?

Well.. of course you can, but if you have managed to read through the information above then you should now know why photoshopping your images to correct these basic problems is a bad idea... but for a technical reason then read on.

But if you are easily geeked out then stop reading now!

One of the problems is with dynamic range... a picture on a computer can only store a limited number of colours. In fact although it can represent over 16.7 million different colours it can only store a paltry 256 levels of grey. This is because each colour is made up of varying quantities of red green and blue. Each of these 3 primary colours is represented by a byte (with a value ranging from 0 to 255) the problem comes when grey is concerned. Grey is made up of equal values of each colour. So 50% grey has a value of 127 for red 127 for green and 127 for blue. As you can see (or perhaps not) as they have to be the same you can therefore only have 256 different levels of grey. This restriction is also true for other colours, but is generally not noticeable in the same way.

To cut to the chase, if you take a picture where you have not correctly set the camera for white balance and brightness then when you edit in photoshop it has to stretch the colours and levels that are available in the picture to make it look right, this ultimately reduces the quality of the end result, because you have less colours and shades in the picture than you should have, you can really notice it in greys and gently shaded areas as mentioned above so by only using a few of the available colours in your original image by not exposing correctly, then you are starting out from a bad position and the end result will never be as good.

Light cubes

To help with photography and reduce reflections you can use a light cube.

These are translucent boxes, usually made from cloth, that allow you to photograph your work in an easy way. You still need to follow all the instructions above, but be warned that unless you introduce deliberate reflections your glass will appear dull or matt

Further information

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