Exposure Pentagon in Macro photography

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anvancy
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Exposure Pentagon in Macro photography

Post by anvancy »

I always had this question in mind specific to macro photography.
As we start to go at 1:1 and beyond, two new factors start to play a big role in how we photograph macro. So the trinity becomes a pentagon.

The effective aperture - Post 1:1, this plays a crucial role in two things. Actual depth and light loss. Because at say 2x your effective aperture is F24 instead of F8, you have to rethink how your light is going to hit and how sharp should be the photo.

Focal plane - this will decide how the overall image will look? After you have hit the proper working distance, any minute movements translates into major shifts in focus area/focal plane which in turn can ruin or make your shot. I have observed this when taking photos of insect eyes close. One minute jerk in the hand and the focus is gone somewhere else.

What I am also thinking is how these two interact with each other. I always thought when you are doing good macro range photos, the effective aperture affects in that focal plane and also causes the "circle of confusion" principle. I have to be precise how I am going to light the insect in that focal plane, with the effective aperture in play and at what angle.

This is all a random thought,but will like some expert views on this.

Anvancy
www.anvancy.com

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MarkSturtevant
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Post by MarkSturtevant »

Reasonable enough. Not sure if you are including shutter speed in your parameters. Of course that effects things since one relys on a fast shutter speed to negate the effects of slight movements. But slower shutter is useful to recover compensate for light loss due to aperture and focal length.
Mark Sturtevant
Dept. of Still Waters

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