Download - Teacher: Kenji Tachibana Digital Photography I. Aperture – Lens Opening 14 slides Copyright © 2003 – 2009 Kenji Tachibana.

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Teacher: Kenji TachibanaDigital Photography IDigital Photography I.

Aperture – Lens OpeningAperture – Lens Opening

14 slides14 slides

Copyright © 2003 – 2009 Kenji Tachibana

Teacher: Kenji TachibanaDigital Photography IDigital Photography IAperture: Lens opening (f/stop)Aperture: Lens opening (f/stop)

MMechanics: echanics:

Light enters the camera through the lens opening Light enters the camera through the lens opening referred to as the aperture. Lens opening are set to referred to as the aperture. Lens opening are set to specific sizes called f/stop.specific sizes called f/stop.Correct exposure is a balance of two (2) things: Correct exposure is a balance of two (2) things: 1.1.Lens opening controlled by f/stop.Lens opening controlled by f/stop.2.2.Lens open duration controlled by shutter speed.Lens open duration controlled by shutter speed.

Both share whole stop setting such as:Both share whole stop setting such as:

F/stops like: 2.8 F/stops like: 2.8 44 5.6 5.6 8 8 Speeds like: 1/125 1/60 1/30 1/15 Speeds like: 1/125 1/60 1/30 1/15

Teacher: Kenji TachibanaDigital Photography IDigital Photography IAperture: Lens opening & f/stopAperture: Lens opening & f/stop

Whole Stop: Whole Stop:

Whole stop Whole stop differencedifference means that the amount of light means that the amount of light entering the lens either doubles or halves. It doubles entering the lens either doubles or halves. It doubles when going from f/4 to f/2.8. It halves when going when going from f/4 to f/2.8. It halves when going from f/4 to f5.6.from f/4 to f5.6.

DoublesDoubles HalvesHalves

More lightMore light Less LightLess Light

Teacher: Kenji TachibanaDigital Photography IDigital Photography IAperture: Lens opening & f/stopAperture: Lens opening & f/stop

FF/Stop: Range/Stop: Range

The compact digital aperture range usually goes from The compact digital aperture range usually goes from f/2.8 to f/8 which is a 3 whole-stop range as shown f/2.8 to f/8 which is a 3 whole-stop range as shown below.below.

F/2.8F/2.8 lets in the most amount of light. And lets in the most amount of light. And f/8f/8 lets in lets in the least amount of light.the least amount of light.

Teacher: Kenji TachibanaDigital Photography IDigital Photography IAperture: Lens opening & f/stopAperture: Lens opening & f/stop

FF/Stop: Compact digital limits/Stop: Compact digital limits

You can’t let in more light through the You can’t let in more light through the bigbig lens opening lens opening than the ‘than the ‘wide openwide open’ f/2.8.’ f/2.8.

Wide-OpenWide-OpenFully Stopped-DownFully Stopped-Down

You can’t let in less light through the You can’t let in less light through the smallsmall lens opening lens opening than the fully ‘than the fully ‘stopped downstopped down’ f/8.’ f/8.

DSLR lenses have different wide open and fully DSLR lenses have different wide open and fully stopped down settings of f/3.5 wide open to stopped stopped down settings of f/3.5 wide open to stopped down f/22 .down f/22 .

Teacher: Kenji TachibanaDigital Photography IDigital Photography IAperture: Lens opening & f/stopAperture: Lens opening & f/stop

FF/Stop: Dangerous limits/Stop: Dangerous limits

Stay away from the limits. It tends to give less than Stay away from the limits. It tends to give less than optimal image quality results.optimal image quality results.

Avoid using f/2.8 (DSLR f/3.5) or f/8 (DSLR f/22). Wide Avoid using f/2.8 (DSLR f/3.5) or f/8 (DSLR f/22). Wide open can suffer from soft edge detail. The fully stopped open can suffer from soft edge detail. The fully stopped down image can have an overall loss of image quality.down image can have an overall loss of image quality.

Teacher: Kenji TachibanaDigital Photography IDigital Photography IAperture: Lens opening & f/stopAperture: Lens opening & f/stop

FF/Stop: Increments/Stop: Increments

Whole stops are sub-divided into 1/3 stop increments Whole stops are sub-divided into 1/3 stop increments as shown below.as shown below.

2.82.8 I II I 4 4 I I I I 5.6 5.6 I II I 88

3.23.2 3.63.6 4.54.5 55 6.36.3 7.17.1

Teacher: Kenji TachibanaDigital Photography IDigital Photography IAperture: Lens opening & f/stopAperture: Lens opening & f/stop

FFraction Notations: raction Notations: Human eye is 1.0Human eye is 1.0

1 1 1 1 1 1 1 1 1 1 1 1

2.82.8 4 4 5.65.6 8 8 1111 1616

1/2.81/2.8 1/41/4 1/5.61/5.6 1/81/8 1/111/11 1/161/16

1÷2.81÷2.8 1÷41÷4 1÷5.61÷5.6 1÷81÷8 1÷111÷11 1÷161÷16

1:1:2.82.8 1:1:44 1:1:5.65.6 1:1:88 1:111:11 1:161:16

Teacher: Kenji TachibanaDigital Photography IDigital Photography IAperture: Lens opening & f/stopAperture: Lens opening & f/stop

FF/Stop: Useable range/Stop: Useable range

The high image quality f/stop range on a compact digital The high image quality f/stop range on a compact digital is from large is from large f/3.2f/3.2 to small to small f/6.3f/6.3 lens opening. lens opening.

2.82.8 3.23.2 3.63.6 44 4.54.5 55 5.65.6 6.36.3 7.17.1 88

Avoid using apertures smaller than f/6.3 if you want Avoid using apertures smaller than f/6.3 if you want maximum optical sharpness. Aperture range from f/7.1 to maximum optical sharpness. Aperture range from f/7.1 to f/8 suffer from lower resolution because of light diffraction. f/8 suffer from lower resolution because of light diffraction. Use the wide open f/2.8 on emergencies only because of Use the wide open f/2.8 on emergencies only because of lower image quality.lower image quality.

Teacher: Kenji TachibanaDigital Photography IDigital Photography IAperture: Lens opening & f/stopAperture: Lens opening & f/stop

FF/stop: Toy camera range/stop: Toy camera range

The f/2.8 to f/8 are the default lens 3-stop range found The f/2.8 to f/8 are the default lens 3-stop range found on most compacts. And even that limited 3-stop range is on most compacts. And even that limited 3-stop range is available only on the wide zoom setting. available only on the wide zoom setting.

The telephoto is limited to 1.4-stop range going from The telephoto is limited to 1.4-stop range going from about f/4.5 to f/8. A simple explanation for this has to do about f/4.5 to f/8. A simple explanation for this has to do with the light travelling further to reach the sensor when with the light travelling further to reach the sensor when the ‘longer’ telephoto zoom setting is used.the ‘longer’ telephoto zoom setting is used.

Teacher: Kenji TachibanaDigital Photography IDigital Photography IAperture: Lens opening & f/stopAperture: Lens opening & f/stop

FF/stop: Comparison/stop: Comparison

The f/2.8 to f/8 are the f/stops for the largest and the smallest The f/2.8 to f/8 are the f/stops for the largest and the smallest apertures on a most compact digitals. The range is a limited 3 stops.apertures on a most compact digitals. The range is a limited 3 stops.

CompactCompact 2.82.8 | | | | 44 | | | | 5.65.6 | | | | 88 Wide OpenWide Open Stopped DownStopped Down

DSLRDSLR 3.53.5 | | | | | | 5.65.6 | | | | 88 | | | | 1111 | | | | 1616 | | | | 2222Wide OpenWide Open Stopped DownStopped Down

The f/3.5 to f/22 are the f/stops for the largest and the smallest The f/3.5 to f/22 are the f/stops for the largest and the smallest apertures on a most DSLR’s. The range is a much larger 5.3 stops. apertures on a most DSLR’s. The range is a much larger 5.3 stops. A more expensive ($1,500?) lens can be purchased with an f/2.8 A more expensive ($1,500?) lens can be purchased with an f/2.8 wide open aperture and that would result in a 6 stop range.wide open aperture and that would result in a 6 stop range.

Teacher: Kenji TachibanaDigital Photography IDigital Photography IAperture: Lens opening & f/stopAperture: Lens opening & f/stop

SSummary:ummary:

It’s through high image quality that an Image Maker It’s through high image quality that an Image Maker conveys love for the medium. Although high image conveys love for the medium. Although high image quality without a meaningful story is usually not that quality without a meaningful story is usually not that interesting. It would be like looking at a never-used interesting. It would be like looking at a never-used chrome plated car engine, a waste of resources…chrome plated car engine, a waste of resources…

Turn to the next slide for a bonus point opportunity

Teacher: Kenji TachibanaDigital Photography IDigital Photography IBonus Assignment:Bonus Assignment:

Three Things Learned:

Write 3 paragraphs about three new things learned from this ‘Digital Camera’ PowerPoint show.

File Name: firstnameLearnAp (kenjiLearnAp.doc)

Due Date: Turn in next class if you want to earn the bonus points.

Use: Turn to the next slide to see the Word™ layout and requirements.

Teacher: Kenji TachibanaDigital Photography IDigital Photography IKnowledge Gained Writing Format:Knowledge Gained Writing Format:

Student Name: First and Last

Assignment: I LearnedClass: Art 114 or 115

Digital PhotoCampus: South Campus

Date: Actual creation date

Report Title: Aperture

Learned 1:In the slide x, I learned that ….. ……… ………… ……….. ……. ….. ….. ….. ….. ….. …..

Learned 2:In the slide x, I learned that ….. ……… ………… ……….. ……. ….. ….. ….. ….. ….. …..

Learned 3: In the x, I learned that ….. ……… ………… ……….. ……. ….. ….. ….. ….. ….. …..

Use Ariel 12 or 13 font and don’t double space (conserve paper please).And use Word’s ‘default’ page layout with 1” x 1” x 1” x 1” margins

Right aligned Right aligned the header infothe header info

Center align Center align the titlethe title

Left aligned the Left aligned the paragraph titlesparagraph titles

Don’t include Don’t include gray textgray text

Don’t include Don’t include the red textthe red text

Teacher: Kenji TachibanaDigital Photography IDigital Photography I

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