GoingManual.com It's time to take control!    Home    Tutorials    Photography Forum  Photography Tutorial Introduction Part I – Gear The Camera  -  Focus  -  Resolution  -  MegaPixels Vs Print Size  -  Sharpening Semi auto settings  -  Aperture Priority (Av)  -  Shutter priority (Tv) Zoom and Focal Length  -  A Note About Sensor Size Other Camera Features  -  Viewfinders  -  Lens Hood  -  LCD screen  -  White Balance Extra Equipment  -  Tripod  -  Cable Release  -  Filter systems  -  Polarizer and ND filter  -  External Flash  -  Studio Lighting  -  Reflectors Part II – Capturing The Scene Your First Manual Photo  -  It's All About Exposure  -  The Light Meter  -  Exposure Explained  -  Controlling Exposure Creative Effects  -  Aperture and Depth Of Field  -  DOF Preview  -  Shutter speed Putting it all Together  -  ISO  -  Ap. & Shutter Relationship  -  Stop for a minute  -  So What?  -  The Bulb Setting Metering the Scene  -  18% of Everything Metering modes  -  Matrix  -  Average  -  Center weighted  -  Spot or semi-spot Taking Meter Readings  -  Expose for your subject  -  Sunsets and sunrises  -  Reflecting sun  -  Night Exposures  -  Moon  -  Green Foliage  -  Bright or White Scenes  -  Dark or Black Scenes Understanding Your Histogram  -  Flash Metering Composition Lead in The Viewer Eye  -  Point of Focus  -  Fill the frame  -  The Rule of Thirds  -  Moving Subjects  -  Print and frame Sizes Different Styles Learn by doing  -  Giving and Getting Critique  -  Portraits  -  Groups  -  Children  -  Shooting Outdoors  -  Silhouettes  -  Macro  -  Products  -  Landscapes  -  Sports and Action  -  Panning  -  Rear Sync Flash  -  Abstract  -  Long Exposures  -  Black and White A few Other Useful Things  -  Blown Out Skies  -  Neutral Density Filters  -  Polarizing Filters  -  Electronic noise You're Half Way There! Part III The Digital darkroom  -  Computer hardware  -  Card Reader  -  Printers  -  Mouse Post Processing  -  The Ethics of Altering  -  Choosing Your Program  -  Tutorials   Photoshop Tutorials   Photoshop Primer   Saving Your Image   Adding a Border   Using Levels   Using Curves   The S-Curve   Correcting White Balance   Improving Saturation   The Clone Tool   Correcting Lens Distortion   Blending Multiple Images   Black and White Conversion   Sepia Conversion   Reducing Noise   Cropping for Different Print Sizes   Sharpening   Working With RAW Files   The Gimp Tutorials   The Gimp Primer   Saving Your Image   Adding a Border   Using Levels   Using Curves   The S-Curve   Correcting White Balance   Improving Saturation   The Clone Tool   Correcting Lens Distortion   Blending Multiple Images   Black and White Conversion   Sepia Conversion   Reducing Noise   Cropping for Different Print Sizes   Sharpening   Working With RAW Files   << Putting it all Together The Bulb Setting >> Stop For a Minute Have you heard the term 'stop' used in photography and were so confused you did just that? Well you're already halfway to understanding it. It's a tricky concept and unfortunately we're still in the bit you'll probably have to read again. Stick at it as once you get through this, we can get to the fun stuff. The increments in the previous sequences are called 'stops'. Here's the important bit. Each increase in one stop will double the amount of light that reaches the sensor. Each decrease in one stop will halve the amount of light. Here a few examples of what I mean. Changing the shutter speed from 1/60s to 1/30s halves the shutter speed. It's slower so it lets in more light. If it's half the speed then twice as much light comes through. This is stopping up by one stop, doubling the amount of light using the shutter speed. Changing 1/30 shutter speed to 1/60 doubles the shutter speed so it halves the amount of light. This is 'stopping down' by one stop, halving the amount of light. Change 1/30 to 1/125 and you've stopped down the shutter by 2 stops (doubled the shutter speed to 1/60 and doubled again) Change 1/500 to 1/2000 and again you've stopped down the shutter by 2 stops, 1/500 > 1/1000 > 1/2000. Changing the aperture from f/11 to f/8 makes the aperture wider by one f stop (remember f/1 is wholly open) so more light get in. This is 'stopping up', increasing the aperture by one f stop. Tip: You can stop up or down buy changing the shutter speed, aperture, ISO or a combination of all three. So What? You frame your scene and adjust the aperture and shutter speed. The light meter's needle is in the right place, indicating a correct exposure. You take your picture but it's not the kind of shot you were after. You might want to change the aperture for creative effect and shorten the depth of field, blurring out the background. Remember to shorten the depth of field we have to widen the aperture. If we make the aperture wider by 2 stops (stop up by 2 stops), we can increase the shutter speed by 2 stops (stop down by 2 stops) and we still have a correct exposure. Take a moment to grasp this concept it's all about using the camera settings to control how much light gets to the sensor. It will give us the creative control we want. Here's a real life example. In 'fully auto' your camera produces a blurry image, so you decide to have a go at a manual shot. You review your cameras settings and see it was choosing the auto settings of 1/30 and f11. The problem is 1/30s is too slow to handhold resulting in unwanted blur. We could use a tripod or alternatively, increase the shutter speed. About 1/60s is an OK speed to hand hold at. What effect will this have on our exposure? Well, we've doubled the shutter speed from 1/30 to 1/60. A faster shutter speed means less light. Twice the speed is half the light reaching the sensor. That's a loss of one stop. We need to stop up the aperture by one stop to compensate and increase the light reaching the sensor. If 1/30s and f/11 was correct according to the light meter in fully auto, then in manual, 1/60 at f/11 will now read one stop underexposed. To get a correct exposure increase the aperture by one stop from f/11 to f/8. Now our camera would be set at 1/60 at f/8. The needle in the light meter will be back in the middle and we can now take our photo without getting the 'hand shake' blur. We loose some DOF but the trade off is worth a sharp image. We have another alternative, which might prove easier for now. Set your camera to Tv, (shutter priority), and use a shutter speed of 1/60s. The camera will then select the best aperture it can based on the available light. ISO can help us achieve our desired shutter speed or aperture setting. In the previous shutter speed examples of the water running over the stones, the settings for the fast shutter speed was 1/125s, f/5.6 and ISO 800. There is still a little blur in the water but the aperture for that lens is as wide as it will go. If we can't increase the size of the aperture we can increase the sensors sensitivity to light. Changing the ISO from 800 to 1600 doubles the sensitivity of the sensor and so is a one stop increase. This allows us to increase the shutter speed by one stop which will halve the light reaching the sensor. The result is 1/500s, f/5.6, ISO 1600 which is the same exposure as 1/125s, f/5.6 and ISO 800. Remember though higher ISO means more grainy noise in your image. << Putting it all Together The Bulb Setting >>

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