Photographing White Birds

[Gatorgirl]

Can someone please tell me what the trick is to photographing white birds or birds with white on them? I have photographed them at all times of day & on overcast days & the photos never look right. There never seems to be enough detail in the feathers. I'm using a Canon Powershot SX10IS. It's almost as good as a DSLR. I can set the f-stop & shutter speed just like on a DSLR or any SLR for that matter.

Thanks for the help.

Kim

[jamesfc]

Hi Kim,
Great question! Photographing white feathers can be a challenge. The first thing you need to make sure you haven't overexposed the bird. It is easy to do, so check your histogram and make sure that the exposure isn't clipping. You may have to drop your exposure compensation down a little. On the other hand, if the bird is filling the frame, then the camera is going to have a tendency to underexposure, so you need to actually boost the exposure! Keep the eposure for the white areas as close to the right of the histogram as possible without clipping.

Make sure the primary light (assuming the sun) is coming from behind you. Art Morris recommends that your shadow point toward the bird. I prefer the light to be a bit more to the left or right to give some dimension to the feathers.

Finally, in photoshop, if there isn't much detail in the whitest area of the feathers, copy these areas to a new layer and set the layer mode to Linear Burn. Adjust the opacity of this layer to until it looks good. The linear burn will help increase definition in the feathers

Hope this helps and welcome to the forum!!

[Gatorgirl]

Thanks Jim. I'll have to look at the instruction book & see how to find & use the histogram. I love the camera but am totally unimpressed with the instruction book. I had to contact Canon to find out how to change to different scenes in the SCN mode. I also need to get a good book on Photoshop. I can do basic editing but stuff like layers & linear burn are beyond me.

Now, how do I get the birds to hold still while I check the histogram?

[jamesfc]

Hi Kim, the histogram is one of the most important aspects of digital photography and there should be a menu function, or button to display the histogram. The histogram is essentially a graph of the luminance of your capture. SInce digital images are linear (not curved like film), the most detail is contained in the brightest parts of the capture, which is the rightmost part of the graph. Ideally, you want data in this part on the histogram. This is what Michael Reichmann refers to as "exposing to the right". Please read his essays at http://www.luminous-landscape.com.

Histogram

histo-yellow.jpg (5.3 KiB) Viewed 16572 times

The above is an example of a histogram and often covers 4-5 stops of the captured exposure.

For using linear burn in Photoshop, copy part (or all) of the image to a new layer and under the layer mode (defaults to "normal"), use the drop-down and set it to linear burn. Then you can add a layer mask and/or use opacity to adjust it to taste!

[Lug1]

So in your example of the histogram one could say that image was slightly underexposed?. < The largest peak to the left> of center. To compensate you would +1/3 stop?

Bob

[jamesfc]

Hi Bob!
Actually - don't look at the peak, that is showing you where most of the tonal values are. Instead you want to look at the edges. See how the histogram approaches, but doesn't go over, the right side? These are the highlights and it is important to try to get this as close to that right edge as possible, without going over the edge. In this instance, I wouldn't add any additional compensation as any more would likely push it over, which is known as "clipping". Once the data goes over that edge, it is lost forever (actually the histograms are based on JPEG images, so if you are shooting RAW, you do have a little more room!!).

The same applies to the left side, but the way photo sensors works (CCDs and CMOS chips), 50% of the detail is contained in the first stop from the right side. So, if you don't have any values up there due to an underexposure, you have thrown away 50% of the detail! The other 50% is contained in the remainder of the histogram.

histogram

histogram2.jpg (31.57 KiB) Viewed 16563 times

Hopefully this illustrates it better - I divided the histogram into the five stop range that it covers. The first stop on the right contains 50% of the detail - the remaining 4 stop contain the rest of the detail - the remaining 50%. So, if you don't have any luminance values in this upper section - you are not recording the maximum detail that you could be! However, you can go right up to that right hand edge, but no further as then you will be clipping, and in the case of the original white bird, you will lose detail and the resulting image will be pure white with no detail. This is OK for clouds, sun, bright lights, etc., but not something that you want to maintain detail!

Remember to view the histogram in the context of the scene that you are recording. If it is a dark scene, the histogram is going to have most of the peaks on the left, if it is a bright scene, most of the peaks will be on the right. The histogram above is likely that of a fairly average scene with an equal balance of bright and dark areas, so it looks like a bell-curve. The important thing is to record the brightest items that you wish to maintain detail go right up to that right edge, without going over.

By the way, if your camera has highlight warnings on the LCD (sometimes called the "blinkies"), this will also help show you what areas of the image have been clipped, or gone over the edge. Again, if it is something bright (like highlights or clouds, etc.) then I wouldn't be too concerned. However, if the white bird is flashing, then there will be no details in those feathers!

Does that help?

[Lug1]

Yes Jim thank you for the clarification. Since I have gone out shooting with you guys I have learned to utilize the histogram almost exclusively. I have gotten alot better although in some tough light situations I still have a bit of an issue. Just need to keep practicing. I have had better luck with my uploads too so I must be doing something right. Hopefully I will continue to get better.

Regards
Bob

[jamesfc]

We need to get together for photography again soon!

I looked back and thought I should perhaps explain the reason for the 50% detail in the right side for electronic chips. For ease of discussion, let's assume an 8 bit image (yeah, I know most of mine are "2 bits", but that's another matter entirely! ). Considering a single color channel, 8 bits would result in a maximum value of 255 (0 - 255), which would be fully saturated. Any value higher than this would be clipped to 255. That's the highest number that can be stored.

OK, that represents full saturation (pure white if all 3 channels are saturated) so reducing the exposure by 1 stop would result in a value half of our 255 value (since a 1 stop reduction cuts the amount of light in half) and would be about 128. Therefore, that first section on the histogram on the right where I indicated is the first stop of the 5 stop range covered by the histogram, contains half of the maximum value allowed!! The other 4 sections, or stops, contain the other 128. By cutting each value in half as we proceed to the left means that the darkest section - the first stop on the left, only contains a maximum value of 16!!! The numeric values of each stop ranges from left to right are 0-15, 16-31, 32-63, 64-127 and 128-255! Hopefully that shows that it is important to get some exposure values up there in that first stop indication on the right, without going over the maximum value. The first 4 stops are values from 0 - 127 and the final stop on the right represents the final 128, fully 50% of the maximum value!!

That's why it is important to push that histogram as far to the right as possible, without going beyond the right hand edge! Keep in mind this is somewhat of a simplification, but hopefully it better explains the concept.

[veronicacarter]

Provided information is very useful after long time waiting I was success to captured one photos of white pigeon .

[jamesfc]

Yes you did! As you can see, due to the limited dynamic range of our sensors, the background grass is darker in order not to blow out the white feathers on the dove. However, on my monitor, the dove looks white and not grey so I would say the exposure is correct for this image!