Purple Flowers on a Leaf

[crysmichelle]

So this is my first time posting, and I'll try to adhere to the posting format. I took this particular shot on Sunday, and it was fairly gray outside; lots of clouds and a little bit of rain. I used a Canon T2i with an 18-200mm IS lens really just trying to test out the macro capabilities as it's a new lens. Mostly I'm looking for thoughts on exposure...I feel that it looks good, but I haven't nailed down how to balance aperture with shutter speed. I also feel that my ISO is waaay too high at 3200. Any specific adjustments I should make?



Macro Purple Flower
Camera Canon EOS REBEL T2i
Exposure 0.001 sec (1/800)
Aperture f/9.0
Focal Length 200 mm
ISO Speed 3200
Flash Off, Did not fire

[mikesieber]

To my eye, it looks a bit underexposed. I think opening your aperture would have allowed more light to get in while blurring the background even more than it is.

And I agree that 3200 ISO is a bit high for shooting outside even on a cloudy day, although your camera is pretty good when it comes to image quality at higher ISO speeds.

Keep shooting and sharing

[chicagojohn]

Originally Posted by mikesieber

To my eye, it looks a bit underexposed. I think opening your aperture would have allowed more light to get in while blurring the background even more than it is.

And I agree that 3200 ISO is a bit high for shooting outside even on a cloudy day, although your camera is pretty good when it comes to image quality at higher ISO speeds.

Keep shooting and sharing

First, I really like the colors and sort of dreamy feeling of the large green leaf and rest of the green background. I think I pretty much agree with this, and the rule-of-thirds placement of the beautiful subject flowers.

I agree pretty much with mikesiber's comments. In addition, however, other things being equal, we should always be shooting at the lowest ISO possible to get a decent exposure.

Both aperture and shutter speed can be used to create desired effects; aperture significantly affects depth of field (the distance range from the lens that is in acceptably sharp focus) and shutter speed can be used to stop or show motion. But the only thing ISO does is increase the amplification of the data from the sensor and with that it also amplifies noise. So low ISO equates to image quality. The only time ISO should be increased is to allow a better balance between aperture and shutter speed as to the intention of the photographer.

Here the shot was at 1/800 s when it could easily be taken at 1/60 (maybe even 1/15 with an antishake system). But let's just go with 1/60. Here are the EV units of increased light exposure associated with this difference; 1/400, 1/200, 1/100, 1/60. That is +4 EV or 4 stops. Each stop doubles the light falling on the sensor.

Now, starting with 3200 ISO amplification, we could go down four EV like this; 1600, 800, 400, 200.

So this image could have received the same exposure as it has shot at ISO 200 and 1/60 s. Then you could go from there, if you wanted to, to adjust the exposure as mikesiber commented. The same effect, however, could be achieved by a levels adjustment in photoshop.