Monday, October 29, 2012

Fooling with the Flash


Boy, I do not like the pop up flash on my camera.Thanks to the reading (and seeing some of your blogs- thanks!) I do understand how the flash can be used to manage shadows, illuminate a subject, or as fill light to even out the exposure. But I'm afraid the pop up flash on my camera is doomed to remain a little used accessory.

One thing I learned these weeks is that if I set the white balance for the appropriate conditions, and then use the flash, the flash will override the white balance. So if I want to use the pop up flash I might as well set the white balance to auto, and that lessens the control I have over my shots.

I went out on a partly cloudy day with the white balance set for shade. I wanted to emphasize the warm yellow leaves on the trees around the block. The first photo is the one I took without the flash.

I took this one with the flash, even though I knew I was too far away for it to have any real effect. I think it looks tepid and dull. This is when I began to realize the connection between the pop up flash and a manually set white balance.




I knew that to use the flash properly, I had to get close to my subject. I really like how this photo came out. Because of the flash, the light on the leaves almost sparkles, and the shadows the leaves are making on each other are visible, but not too dark.








Many of the experiments I did with the flash resulted in washed out shots like this one.







 I like the no flash picture better.













If you want soft shadows, use the flash. If you want sharp shadows, don't use the flash because it will add light and soften the shadows.

It's fun to play with the flash. These are some pictures I made by shooting into a mirror and a pane of empty glass. The first picture has nothing over the flash. Then I used a paper napkin to drape over the flash and I like how it looks. They are pretty abstract.


Sunday, October 14, 2012

White Balance

I have always felt I could pretty much ignore this setting on my camera, which turns out to be mostly true, for everyday photos. But not entirely!  My camera, with it's white balance set on AUTO, makes good guesses about true color. But this assignment showed me that I can help the camera out by using the settings to make its job easier. 







I took this photo before I knew anything about white balance settings. I had just painted this room and wanted to show my son, who lives in D.C.  The AUTO white balance setting did a good job.  It's close enough to the actual color of the paint and I was mostly satisfied.








For the first photo I took for this assignment, I left the WB setting on AUTO for comparison purposes. 


It was a cloudy day, so next I set the WB to SHADE to warm the colors up a little bit. My camera doesn't have a setting for CLOUDY but I figured this would have the same effect. I think the color looks unnatural; it's too yellow.


I wanted to see what the camera would do if I told it that I was using incandescent light - here is the result. The camera compensated by toning down the warm tones from the picture and the resulting shot is very cold and blue. Pretty awful.



After I understood the effects you can get by overriding the camera's AUTO white balance settings, I played around with some apples.
This is the same room as the first photo, so if you look at the wall behind the table you can see that the AUTO setting captured the color most accurately. The FLUORESCENT setting added warm yellow tones, and the TUNGSTEN setting removed them and made the wall look blue.



tungsten      


auto

fluorescent     


Now, what if you wanted to created a particular effect? I did that here. I put the lens on Macro close-up, used a tripod and a super slow shutter speed to take this shot of some shells and things in a thick, bubbly glass vase.  I was going for a dreamy, other-worldly kind of feeling. On the first shot I set the white balance to compensate for the incandescent light. The second shot has the white balance on AUTO. Which one looks more magical?




Monday, October 8, 2012

Learning about ISO settings -

  I am beginning to understand exactly how the ISO setting is related to aperture and shutter speed. The sensor is the part of the camera that records the available light. The aperture determines how much light will hit the sensor, and the shutter speed determines for how long the light will hit the sensor. SO - the ISO setting determines how sensitive the sensor is to the light. In other words, the ISO setting determines how bright your image is going to be.
   Deciding which ISO setting to use depends on multiple factors: the effect you want to achieve, the amount of light available, whether you want to use a particular aperture setting, and how much noise you're willing to accept in the digital image.

f5.6   1/42   ISO 64

  

   For this first set of images,  I decided to leave the aperture set at 5.6, so that I could see the relationship between a variable shutter speed and ISO.  Here is a shot taken at the lowest ISO my camera allows me to use. The shutter speed is not slow enough for camera shake to be a problem, */and at this ISO the sensor is not as sensitive to light as it would be at a higher setting. Note the deep shadows.

f5.6   1/75   ISO 100


                                                                                                                                                   
Here is a picture shot at a more commonly chosen ISO, 100.  On a sunny day, which this wasn't, this setting would give you a clean crisp shot with no noise, and a slightly faster shutter speed. I noticed that as the ISO setting rose, the shutter speed shortened.  The color in the first photo is a little more saturated than in this one, but this is still acceptable.




f5.6  1/140  ISO 200

It's a little boring to keep taking the same shot but I thought it would be good for comparison purposes.  Here, the ISO setting is doubles, which caused the shutter speed to roughly double too, to compensate for the increased sensitivity of the sensor.






f5.6  1/250  ISO 400

You can see the mathematical relationship developing here. Every time the ISO doubles, the shutter speed comes close to doing the same. This is because the sensor is becoming more sensitive to light, so the shutter must shorten the time that light is allowed to hit it.







f5.6  1/480  ISO 800



With the ISO set at 800, this photo is beginning to look washed out. The colors are less intense and the detail is less fine.









f5.6  1/1000  ISO 1600


Again, the ISO has doubled, and the shutter speed is more than twice as fast. The color is duller yet, almost a gray green, and the yellow flower in the center is much paler.









f5.6  1/2000  ISO 6400


I've jumped to the last photo - the highest ISO I could get. At this setting the sensor is extremely sensitive to light, so the colors are not accurately captured. The shutter speed and aperture would both have to be changed to get proper exposure, and even then it might not be possible with an ISO setting this high. If you enlarge this picture you will see enormous noise, or what would be called grain if this were taken with a film camera.




These last two photos show the effects you can get by playing with the ISO setting. The picture on the left had an ISO setting of 100. The one on the right is ISO 800.  To me, the one on the left looks fresh and bright, while the one on the right looks old and faded.