Thursday, June 9, 2011


Well spring is over at least here in the desert.   It is close to 100 today .  I know there is no humidity.  All that humidity thing means is you don't know your dehydrating.  It also means those beautiful weeds have wilted.  You know the ones.  The ones that are treated with roundup.   Of course, there are those others that need more attention than a 2 year old at the county fair.   They need watering, fertilizing and pulling those other flowers called weeds.

Well I'm going to be talking about ISO, shutter speed, and F-stop again.   Just in case you had forgotten I will be talking about light since it is thing we photograph no matter the subject.

Flower 1.   (Weed to some)

THis is an old photograph taken with something called film.  It is one of my favorites.   I do not know the ISO, shutter speed, or F-stop.  I just love the simplicity.  It is straight on and the flower is not perfect, but the light I just love. It is hard to catch white and still find detail like this.  I suspect that it was taken in the evening not too long before the sunset.   The hour just after the sun rises and just before it sets are usually the best for taking photographs like this one.  The light has a soft glow to it.

Flower 2 or are they weeds.

ISO 100, F-stop 7.1, 1/1600   Same type of flower, but taken several years later.   I took this because I just wondered what they would look like from the ground.  We always look down on them and frequently pull them.  Since, the flower is not going to run off why not take more than one picture  explore all the angles and all the ways light hits them. 

Flower three.

ISO 200, F 8, 1/40.   Remember that discussion about the best light, this was taken at about noon bright sunshiny day, so much for rules.  Yes I have to admit I have worked this pretty hard in photoshop.  I don't do that very often, but so much for rules.  If I would have just shot the photograph the flower would have been underexposed.  Remember there was bright light.  So I got close enough to the flower that only it was showing.  I recorded the shutter speed and the F-stop.  I framed the photograph and snapped the shutter.  The building in the background was now overexposed and did show in the photograph.  

Flower 4

ISO 100, F-stop 5, shutter Speed 1/50  Here is I used the same principal except in reverse.  This time I was at a dinner party, that is potato chips in the background when I took this.  The flowers however were in the light and the background was dark.  The lesson is cameras only see about two stops of light.   I know some of you are saying what?   Two stops?  Let's just say we have a camera set up to shoot at these settings ISO 400, Shutter speed  1/250, and F-stop 8.   Now let's say we want to adjust the settings by a stop.  We could change the ISO to 800 and leave the other settings alone.  About twice as much light would get to the sensor and the adjustment would be 1 stop.  So in the example we increased the light by one stop.  We could decrease it by changing the ISO to 200.  The ISO would be decreased by one stop.  We could do the same thing with the shutter speed or the F-stop.  To increase by a stop double the shutter speed to 1/500 or decrease it by cutting in half to 1/125,  and with the F-stop to increase by a stop set it to F-4 or decrease it by setting it to f 16.  In the two flower examples I used this principal to my advantage.  It can be a problem such as photographing a group of people some in the shade and some not. 

Flower 5 

ISO 100, Shutter Speed 1/2500, F stop 1.4  THis photograph has been cropped for two reasons.  The first reason is because I like it that way.  The other reason is to draw attention to the center of the flower.  I did this by choosing an F-stop of  1.4 and creating a shallow depth of field.  You can see that hardly any of this photograph is in focus.   Usually I will not use an F-stop less than F4.  This is a rule of thumb.  The only thing to keep in mind is the closer you get to the subject the narrower the depth of field at the same F-stop.   As an example (I am now going to make up numbers, but the theory is good)  at F-stop 1.4 and at about 12 inches from the subject there may only be 1/2 inch in focus, but at 20 feet there may be 12 inches in focus.   In other words the closer to the subject the narrower the depth of field, and the further away the wider the depth of field.

Next time sports, and from then on it will be my travels and photographs like this:
  Well maybe not like this, but the things I photograph. 

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