Tuesday, April 26, 2011
Friday, April 22, 2011
The Power of Words
"The difference between the right word and the almost right word is the difference between lightning and the lightning bug."
--Mark Twain
--Mark Twain
Saturday, April 16, 2011
Tuesday, April 5, 2011
The Rule of Thirds and the Golden Ratio in Web Design and Photography
http://www.arsgrafik.com/rule-thirds-golden-ratio-web-design-photography/
เรื่องเก่าเอาเก็บไว้เล่าใหม่ค่ะ ^^ You can see how the rule of thirds influences web design even in basic blog layouts. When we designed our blog, we created a two-column theme to maintain order and minimize distractions away from the actual content. A two-column theme also allows for larger image sizes, and this site is (obviously) going to be graphically-focused so we need all the space we can get! In terms of the rule of thirds, you can see that our sidebar column takes up around a third of the page layout.
"We all know how important it is to create stellar image composition. But you don’t have to have an “artist’s eye” in order to wow your viewers—just follow these timeless techniques to ensure that your designs are spot-on every time.
The rule of thirds is commonly used in composition today, but the concept has dated back some 2,400 years to ancient Greece with the mathematical discovery of the golden ratio. Without getting into the nitty gritty of the equation, it shows that asymmetry and a 1:3 proportion are aesthetically (and scientifically) pleasing.
Nature abounds with the golden ratio, as you can see from the nautilus image above. My sketch on top of it further demonstrates the ratio. First, you see the outer rectangle with a geometric arc that intersects at pivotal points to create a spiral. Looking closer, you’ll notice that the outer rectangle is cut in two, giving us a square and another rectangle. The ratio repeats itself again and again in each rectangle, leading eventually to a “sweet spot,” where the rectangles grow smaller and become more concentrated.
There are a total of four sweet spots in the golden rectangle, depending on how you first begin constructing it—think about where that spot would be located if you were to flip this image horizontally and vertically.
It’s a good idea to keep these sweet spots in mind when framing and editing images. I’ve posted some of my own images below to show how the rectangle can be applied to photographs to make for some easy editing.
Notice how your eye goes directly to the boat in the sunset.
The rule of thirds and the golden ratio are important philosophies to remember when framing images, but don’t let them override your own creative spirit. There will always be exceptions to the rule, but as I learned long ago, you have to learn the rules before you can break them."
Hyperfocal Distance
http://www.dofmaster.com/hyperfocal.html
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"The concept of hyperfocal distance is easy to understand: focus a lens at the hyperfocal distance and everything in the photograph from some near distance to infinity will be sharp. Landscape photographs are often taken with the lens focused at the hyperfocal distance; near and distant objects are sharp in the photos.
Application of the concept leads to many questions: Which lenses are best for using hyperfocal distance focusing? What is the hyperfocal distance for a lens? How do I focus at the hyperfocal distance? Do I have to focus exactly at the hyperfocal distance? In this article we'll look at the basics of using hyperfocal distance to maximize depth of field in a photograph... Read more
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Where to focus (Hyper Focal Distance)
เรื่องการหาจุดโฟกัสในการถ่ายภาพแบบแลนด์สเคปนี้มีปัญหามานานและยังมีบ้างต่อไป แต่น้อยลง (ขอบคุณคุณJoe Panch ที่เคยแนะนำเรื่องนี้ไว้) หาที่เขียนดีๆ ให้เข้าใจได้ง่ายมานานเพิ่งเจอค่ะ เลยเอามาแปะเผื่อมีคนมีปัญหาเดียวกันจะสนใจ
by Jeff Revell, Canon 50D, From Snapshots to Great Shots, Peachpit Press, 2009, pp-182-183
"Large landscape scenes are great fun to photograph, but they can present a problem: where exactly do you focus when you want everything to be sharp? Since our goal is to create a great landscape photo, we will need to concentrate on how to best create and image that is tack sharp, with a depth of field that renders great focus throughout the scene.
I have already stressed the importance of good tripod when shooting landscapes. The tripod lets you concentrate on the aperture portion of the exposure without worrying how long your shutter will be open. This is because the tripod provides the stability to handle any shutter speed you might need when shooting at small apertures. I find that for most of my landscape work I set my camera to Aperture Priority mode and the ISO to 100 (for a clean, noise-free image).
However, shooting with the smallest aperture on your lens doesn't necessarily mean that you will get the proper sharpness throughout your image. The real key is knowing where in the scene to focus our lens to maximize the depth of field for our chosen aperture. To do this, you must utilize something called the "hyper focal distance" of your lens.
Hyper focal distance, also referred to as HFD, is the point of focus that will give you the greatest acceptable sharpness from a point near your camera all the way out to infinity. If you combine good HFD practice in combination with a small aperture, you will get images that are sharp to infinity.
There are a couple of ways to do this, and the one that is probably the easiest, as you might guess, is the one that is most widely used by working pros. When you have your shot all set up and composed, focus on an object that is about one-third of the distance into your frame. It is usually pretty close to the proper distance and will render favorable results. When you have the focus set, use your Depth of Field preview button to check the sharpness of all the objects in your scene. The button is located just under the lens release button and is activated once you have depressed the the shutter button partway."
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เอาข้อมูลที่อ่านมา กับที่มีคนเอามาฝากมาแปะรวมกันตรงนี้ค่ะ (ขอบคุณNapnik สำหรับข้อมูลเพิ่มเติมค่ะ)
From the link above: HFD from dofmaster.com
"The concept of hyperfocal distance is easy to understand: focus a lens at the hyperfocal distance and everything in the photograph from some near distance to infinity will be sharp. Landscape photographs are often taken with the lens focused at the hyperfocal distance; near and distant objects are sharp in the photos.
Application of the concept leads to many questions: Which lenses are best for using hyperfocal distance focusing? What is the hyperfocal distance for a lens? How do I focus at the hyperfocal distance? Do I have to focus exactly at the hyperfocal distance? In this article we'll look at the basics of using hyperfocal distance to maximize depth of field in a photograph... Read more
Where to focus (Hyper Focal Distance)
เรื่องการหาจุดโฟกัสในการถ่ายภาพแบบแลนด์สเคปนี้มีปัญหามานานและยังมีบ้างต่อไป แต่น้อยลง (ขอบคุณคุณJoe Panch ที่เคยแนะนำเรื่องนี้ไว้) หาที่เขียนดีๆ ให้เข้าใจได้ง่ายมานานเพิ่งเจอค่ะ เลยเอามาแปะเผื่อมีคนมีปัญหาเดียวกันจะสนใจ
by Jeff Revell, Canon 50D, From Snapshots to Great Shots, Peachpit Press, 2009, pp-182-183
"Large landscape scenes are great fun to photograph, but they can present a problem: where exactly do you focus when you want everything to be sharp? Since our goal is to create a great landscape photo, we will need to concentrate on how to best create and image that is tack sharp, with a depth of field that renders great focus throughout the scene.
I have already stressed the importance of good tripod when shooting landscapes. The tripod lets you concentrate on the aperture portion of the exposure without worrying how long your shutter will be open. This is because the tripod provides the stability to handle any shutter speed you might need when shooting at small apertures. I find that for most of my landscape work I set my camera to Aperture Priority mode and the ISO to 100 (for a clean, noise-free image).
However, shooting with the smallest aperture on your lens doesn't necessarily mean that you will get the proper sharpness throughout your image. The real key is knowing where in the scene to focus our lens to maximize the depth of field for our chosen aperture. To do this, you must utilize something called the "hyper focal distance" of your lens.
Hyper focal distance, also referred to as HFD, is the point of focus that will give you the greatest acceptable sharpness from a point near your camera all the way out to infinity. If you combine good HFD practice in combination with a small aperture, you will get images that are sharp to infinity.
There are a couple of ways to do this, and the one that is probably the easiest, as you might guess, is the one that is most widely used by working pros. When you have your shot all set up and composed, focus on an object that is about one-third of the distance into your frame. It is usually pretty close to the proper distance and will render favorable results. When you have the focus set, use your Depth of Field preview button to check the sharpness of all the objects in your scene. The button is located just under the lens release button and is activated once you have depressed the the shutter button partway."
อันนี้เป็นลิงก์สำหรับคนชอบคำนวณ
* :: Focus Pocus :: Depth of Field Calculators for Photographers
อันนี้ลิงก์ต้นกระทู้จาก pantip.com ค่ะ แต่บางทีคลิ้กแล้วหาหน้าไม่เจอจากทางนี้ แปะไว้ก่อน เผื่อกลับมาแล้วเข้าได้
http://topicstock.pantip.com/camera/topicstock/O3001253/O3001253.html
Starburst Effects - เทคนิคถ่ายดวงอาทิตย์ให้เป็นแฉก
http://www.earthboundlight.com/phototips/starburst-effects.html
วันก่อนหาข้อมูลเรื่องนี้อยู่ แล้วพอดีวันนี้คุณ MyColor เอาฉบับภาษาไทยมาฝาก เลยมาแปะไว้เพื่อง่ายต่อการสืบค้นนะคะ -- ข้อมูลภาษาไทยบ่งถึงข้อจำกัดว่าถ้าเราใช้กล้องแบบคร้อปเซนเซอร์ (cropped sensor หรือ ASP-C) ก็จำเป็นต้องใช้ใช้เลนส์ที่กว้างมากๆ อย่าง 10-20 มม ไปเลย แต่ภาษาอังกฤษอธิบายเรื่อง diffraction ไว้ให้เห็นความสัมพันธ์ระหว่างรูรับแสงกับ focal length ของเลนส์ในการเอามาสร้างใ้ห้เกิดแสงแฉก -- คงต้องอ่านเองนะคะ มิบังอาจแปล เดี๋ยวผิด เพราะไม่ได้เข้าใจลึกซึ้ง
เทคนิคถ่ายดวงอาทิตย์ให้เป็นแฉกๆ จาก fisheyecamerah.com
"เห็นภาพถ่ายย้อนแสงดวงอาทิตย์เป็นฉากประกายแบบนี้แล้ว คุณอยากถ่ายภาพแบบนี้บ้างไหม? ถ้าอยากมาเริ่มกันเลยครับ อันดับแรกคือ คุณจำเป็นต้องมีเลนส์มุมกว้างพิเศษ ลำพังเลนส์คิทที่คิดมากับกล้องเช่น 18-55 มม. แม้ว่าช่วง 18 มม. จะมีองศารับภาพกว้าง แต่กับกล้องที่ไม่ใช่ฟูลเฟรม ต้องคูณทางยาวโฟกัสเพิ่ม 1.5 หรือ 1.6 เท่า จะเทียบเท่ากับเลนส์มุมกว้างประมาณ 28 มม. ซึ่งน้อยเกินไปสำหรับการถ่ายภาพประเภทนี้ แต่ถ้ากับกล้องฟูลเฟรม เลนส์ที่เหมาะสมอยู่ในช่วงทางยาวโฟกัส 20 มม. ลงไปจนถึงเลนส์ตาปลาที่ให้มุมภาพกว้างสุดๆ ถึง 180 องศา ส่วนกล้องที่ไม่ใช่ฟูลเฟรม หรือใช้เซ็นเซอร์ขนาด APS-C ต้องมีเลนส์มุมกว้างประมาณ 12 มม. ลงไป เช่น ซูม 10-22 มม. เป็นต้น สำหรับกล้องพานาโซนิคและโอลิมปัสที่ใช้เซ็นเซอร์ขนาด 4/3 ต้องใช้เลนส์ทางยาวโฟกัสต่ำกว่า 10 มม. เช่นกัน
ลำดับต่อไปคือ ต้องถ่ายภาพในวันที่ท้องฟ้าแจ่มใส ไม่มีเมฆ ลองดูภาพตัวอย่างทั้งหมด จะเห็นว่าท้องฟ้าเป็นสีน้ำเงินเข้มอย่างสวยงาม และต้องถ่ายในช่วงเวลาประมาณสามโมงเช้าไปจนถึงสามโมงเย็น เนื่องจากช่วงเวลาดังกล่าวดวงอาทิตย์อยู่ในตำแหน่งสูงพอสมควรและมีแสงแดดจัด เมื่อทุกอย่างพร้อม ต่อไปก็ต้องมองหาซับเจคท์หรือจุดสนใขในภาพ ถ้าเป็นไปได้ควรมองหาวัตถุที่มีการสะท้อนแสงมากๆ หรือมีลักษณะโปร่งแสง เนื่องจากการถ่ายภาพจะปรับค่าแสงเน้นไปทางอันเดอร์ หรือไม่ก็ถ่ายซับเจคท์ให้เป็นซิลลูเอทหรือเงาดำไปเลย
สำหรับการวัดแสง ไม่จำเป็น เพียงแค่ปรับโหมดบันทึกภาพไปที่แมนนวล (ปรับความเร็วชัตเตอร์และรูรับแสงเอง) แล้วใช้กฏซันนี่ 16 คือ ตั้งความไวแสง ISO 100 ความเร็วชัตเตอร์ 1/125 วินาที รูรับแสง f/16 เท่านี้ก็ใช้ได้ ไม่ว่าจะไปถ่ายภาพที่ไหน ความสว่างของดวงอาทิตย์ในวันที่ท้องฟ้าปรอดโปร่งจะใกล้เคียงกัน หากเป็นกล้องนิคอนที่มีความไวแสงเริ่มต้น ISO 200 ให้เปลี่ยนความเร็วชัตเตอร์เป็น 1/250 วินาที หรือเปลี่ยนรูรับแสงเป็น f/22 อย่างใดอย่างหนึ่ง
จบเรื่องการวัดแสง ก็มาถึงขั้นตอนสุดท้ายคือ มุมมองและการจัดองค์ประกอบภาพ แน่นอนว่าเราต้องการถ่ายภาพให้เห็นดวงอาทิตย์ ดังนั้นต้องระมัดระวังเรื่องการมองดูภาพในช่องมองให้ดี แสงสว่างจ้าของดวงอาทิตย์อาจส่งผลเสียกับสายตาของเราก็เป็นได้ หากที่กล้องมีฟังก์ชั่น Live View ให้ดูภาพจากจอมอนิเตอร์ LCD แทนการดูในช่องมองภาพ หรือใช้วิธีการคาดคะเนมุมภาพโดยไม่ต้องดูจากช่องมอง หากต้องการดูภาพให้ช่องมองจริงๆ ให้ดูอย่างรวดเร็วแล้วกดชัตเตอร์บันทึกภาพทันที อย่ามองแช่เป็นเวลานานๆ เหมือนการถ่ายภาพตามปกติ ถ้าถ่ายภาพด้วยกฏซันนี่ 16 แล้วพบว่า ดวงอาทิตย์สว่างจ้าเกินไป ไม่ปรากฏเป็นแฉกเหมือนภาพตัวอย่าง ให้ถ่ายอันเดอร์ลงไปอีก 1 สตอป จะปรับความเร็วชัตเตอร์สูงขึ้น หรือปรับรูรับแสงเล็กลงก็ได้ อย่างใดอย่างหนึ่ง ลองดูนะครับ แล้วคุณจะพบภาพที่แปลกใหม่อย่างที่ไม่เคยถ่ายได้มาก่อน"
Starburst Effects - Photo Tips @ Earthbound Light
Starburst Effects - Photo Tips @ Earthbound Light
Starburst Effects
Turning the sun into a starburst can add a special something to a photograph. Making it happen though can seem like blind luck, but there is a secret to increasing your odds.
The aperture of a lens is formed by an overlapping arrangement of blades that open and close to control the amount of light reaching the film. A spreading of light known as diffraction along the boundaries between these blades at small openings results in the starburst effect. The smaller the opening, the more pronounced the effect.
As was mentioned last week, a lens's aperture number is a ratio between the diameter of its opening and its focal length. As such, if a lens is set to an aperture of f/22, it has an opening with a diameter that is 1/22 of its focal length. Contrary to you might think at first, if you keep the diameter of the opening the same but increase the focal length, the aperture doesn't stay the same. Take a 50mm lens and set it to f/22. Then take a 100mm lens (twice the focal length) and set it so that its opening is exactly the same size as the 50mm lens. The aperture of the 100mm lens would be a ridiculous f/45 (double that of the 50mm lens), in order to maintain the same ratio (50 divided by 22 is the same as 100 over 45). Since there is no such thing (generally speaking) as an f/45 lens for an SLR, you will likely need to settle for an f/22 aperture on that 100mm lens which would be a bigger hole than would f/22 on that 50mm lens.
Sunset on First BeachSo, in order to get more chance of diffraction, you should use a small lens opening, and you will get a smaller opening if the lens you use is a wide angle lens instead of a telephoto, since by definition this will give you a smaller focal length and therefore a smaller lens opening for a given aperture.
The number of streaks in the starburst depends on the number of blades in the aperture. The diffraction occurs at each point where two blades overlap and spreads in both directions from the center of the lens outwards. Lenses that have an even number of blades will yield starbursts that have the same number of streaks as blades since each streak will have a counterpart from the opposite aperture blade that lines up with it exactly. If a lens has an odd number of aperture blades (as most actually do) you will end up with twice as many streaks as aperture blades since no overlap will occur.
As you probably already know, along with all the other "special effects" filters currently available, you can buy so called "starburst" filters, so all this may sound like more bother than it's worth. In my experience though, these filters rarely yield optimal results. They allow you to create starbursts even when they wouldn't normally occur. And wouldn't really rather have the real thing anyway?
Update 12/12/2004: If you shoot with digital, you might not want to go all the way to f/22. Diffraction though that small of an aperture can start to soften an image more on digital due to the smaller sensor size. You can still get great starbursts at f/16 though.
วันก่อนหาข้อมูลเรื่องนี้อยู่ แล้วพอดีวันนี้คุณ MyColor เอาฉบับภาษาไทยมาฝาก เลยมาแปะไว้เพื่อง่ายต่อการสืบค้นนะคะ -- ข้อมูลภาษาไทยบ่งถึงข้อจำกัดว่าถ้าเราใช้กล้องแบบคร้อปเซนเซอร์ (cropped sensor หรือ ASP-C) ก็จำเป็นต้องใช้ใช้เลนส์ที่กว้างมากๆ อย่าง 10-20 มม ไปเลย แต่ภาษาอังกฤษอธิบายเรื่อง diffraction ไว้ให้เห็นความสัมพันธ์ระหว่างรูรับแสงกับ focal length ของเลนส์ในการเอามาสร้างใ้ห้เกิดแสงแฉก -- คงต้องอ่านเองนะคะ มิบังอาจแปล เดี๋ยวผิด เพราะไม่ได้เข้าใจลึกซึ้ง
เทคนิคถ่ายดวงอาทิตย์ให้เป็นแฉกๆ จาก fisheyecamerah.com"เห็นภาพถ่ายย้อนแสงดวงอาทิตย์เป็นฉากประกายแบบนี้แล้ว คุณอยากถ่ายภาพแบบนี้บ้างไหม? ถ้าอยากมาเริ่มกันเลยครับ อันดับแรกคือ คุณจำเป็นต้องมีเลนส์มุมกว้างพิเศษ ลำพังเลนส์คิทที่คิดมากับกล้องเช่น 18-55 มม. แม้ว่าช่วง 18 มม. จะมีองศารับภาพกว้าง แต่กับกล้องที่ไม่ใช่ฟูลเฟรม ต้องคูณทางยาวโฟกัสเพิ่ม 1.5 หรือ 1.6 เท่า จะเทียบเท่ากับเลนส์มุมกว้างประมาณ 28 มม. ซึ่งน้อยเกินไปสำหรับการถ่ายภาพประเภทนี้ แต่ถ้ากับกล้องฟูลเฟรม เลนส์ที่เหมาะสมอยู่ในช่วงทางยาวโฟกัส 20 มม. ลงไปจนถึงเลนส์ตาปลาที่ให้มุมภาพกว้างสุดๆ ถึง 180 องศา ส่วนกล้องที่ไม่ใช่ฟูลเฟรม หรือใช้เซ็นเซอร์ขนาด APS-C ต้องมีเลนส์มุมกว้างประมาณ 12 มม. ลงไป เช่น ซูม 10-22 มม. เป็นต้น สำหรับกล้องพานาโซนิคและโอลิมปัสที่ใช้เซ็นเซอร์ขนาด 4/3 ต้องใช้เลนส์ทางยาวโฟกัสต่ำกว่า 10 มม. เช่นกัน
ลำดับต่อไปคือ ต้องถ่ายภาพในวันที่ท้องฟ้าแจ่มใส ไม่มีเมฆ ลองดูภาพตัวอย่างทั้งหมด จะเห็นว่าท้องฟ้าเป็นสีน้ำเงินเข้มอย่างสวยงาม และต้องถ่ายในช่วงเวลาประมาณสามโมงเช้าไปจนถึงสามโมงเย็น เนื่องจากช่วงเวลาดังกล่าวดวงอาทิตย์อยู่ในตำแหน่งสูงพอสมควรและมีแสงแดดจัด เมื่อทุกอย่างพร้อม ต่อไปก็ต้องมองหาซับเจคท์หรือจุดสนใขในภาพ ถ้าเป็นไปได้ควรมองหาวัตถุที่มีการสะท้อนแสงมากๆ หรือมีลักษณะโปร่งแสง เนื่องจากการถ่ายภาพจะปรับค่าแสงเน้นไปทางอันเดอร์ หรือไม่ก็ถ่ายซับเจคท์ให้เป็นซิลลูเอทหรือเงาดำไปเลย
สำหรับการวัดแสง ไม่จำเป็น เพียงแค่ปรับโหมดบันทึกภาพไปที่แมนนวล (ปรับความเร็วชัตเตอร์และรูรับแสงเอง) แล้วใช้กฏซันนี่ 16 คือ ตั้งความไวแสง ISO 100 ความเร็วชัตเตอร์ 1/125 วินาที รูรับแสง f/16 เท่านี้ก็ใช้ได้ ไม่ว่าจะไปถ่ายภาพที่ไหน ความสว่างของดวงอาทิตย์ในวันที่ท้องฟ้าปรอดโปร่งจะใกล้เคียงกัน หากเป็นกล้องนิคอนที่มีความไวแสงเริ่มต้น ISO 200 ให้เปลี่ยนความเร็วชัตเตอร์เป็น 1/250 วินาที หรือเปลี่ยนรูรับแสงเป็น f/22 อย่างใดอย่างหนึ่ง
จบเรื่องการวัดแสง ก็มาถึงขั้นตอนสุดท้ายคือ มุมมองและการจัดองค์ประกอบภาพ แน่นอนว่าเราต้องการถ่ายภาพให้เห็นดวงอาทิตย์ ดังนั้นต้องระมัดระวังเรื่องการมองดูภาพในช่องมองให้ดี แสงสว่างจ้าของดวงอาทิตย์อาจส่งผลเสียกับสายตาของเราก็เป็นได้ หากที่กล้องมีฟังก์ชั่น Live View ให้ดูภาพจากจอมอนิเตอร์ LCD แทนการดูในช่องมองภาพ หรือใช้วิธีการคาดคะเนมุมภาพโดยไม่ต้องดูจากช่องมอง หากต้องการดูภาพให้ช่องมองจริงๆ ให้ดูอย่างรวดเร็วแล้วกดชัตเตอร์บันทึกภาพทันที อย่ามองแช่เป็นเวลานานๆ เหมือนการถ่ายภาพตามปกติ ถ้าถ่ายภาพด้วยกฏซันนี่ 16 แล้วพบว่า ดวงอาทิตย์สว่างจ้าเกินไป ไม่ปรากฏเป็นแฉกเหมือนภาพตัวอย่าง ให้ถ่ายอันเดอร์ลงไปอีก 1 สตอป จะปรับความเร็วชัตเตอร์สูงขึ้น หรือปรับรูรับแสงเล็กลงก็ได้ อย่างใดอย่างหนึ่ง ลองดูนะครับ แล้วคุณจะพบภาพที่แปลกใหม่อย่างที่ไม่เคยถ่ายได้มาก่อน"
Starburst Effects - Photo Tips @ Earthbound Light
Starburst Effects - Photo Tips @ Earthbound Light
Starburst Effects
Turning the sun into a starburst can add a special something to a photograph. Making it happen though can seem like blind luck, but there is a secret to increasing your odds.
The aperture of a lens is formed by an overlapping arrangement of blades that open and close to control the amount of light reaching the film. A spreading of light known as diffraction along the boundaries between these blades at small openings results in the starburst effect. The smaller the opening, the more pronounced the effect.
As was mentioned last week, a lens's aperture number is a ratio between the diameter of its opening and its focal length. As such, if a lens is set to an aperture of f/22, it has an opening with a diameter that is 1/22 of its focal length. Contrary to you might think at first, if you keep the diameter of the opening the same but increase the focal length, the aperture doesn't stay the same. Take a 50mm lens and set it to f/22. Then take a 100mm lens (twice the focal length) and set it so that its opening is exactly the same size as the 50mm lens. The aperture of the 100mm lens would be a ridiculous f/45 (double that of the 50mm lens), in order to maintain the same ratio (50 divided by 22 is the same as 100 over 45). Since there is no such thing (generally speaking) as an f/45 lens for an SLR, you will likely need to settle for an f/22 aperture on that 100mm lens which would be a bigger hole than would f/22 on that 50mm lens.
Sunset on First BeachSo, in order to get more chance of diffraction, you should use a small lens opening, and you will get a smaller opening if the lens you use is a wide angle lens instead of a telephoto, since by definition this will give you a smaller focal length and therefore a smaller lens opening for a given aperture.
The number of streaks in the starburst depends on the number of blades in the aperture. The diffraction occurs at each point where two blades overlap and spreads in both directions from the center of the lens outwards. Lenses that have an even number of blades will yield starbursts that have the same number of streaks as blades since each streak will have a counterpart from the opposite aperture blade that lines up with it exactly. If a lens has an odd number of aperture blades (as most actually do) you will end up with twice as many streaks as aperture blades since no overlap will occur.
As you probably already know, along with all the other "special effects" filters currently available, you can buy so called "starburst" filters, so all this may sound like more bother than it's worth. In my experience though, these filters rarely yield optimal results. They allow you to create starbursts even when they wouldn't normally occur. And wouldn't really rather have the real thing anyway?
Update 12/12/2004: If you shoot with digital, you might not want to go all the way to f/22. Diffraction though that small of an aperture can start to soften an image more on digital due to the smaller sensor size. You can still get great starbursts at f/16 though.
The Life-saving F/16 Rule for Landscape Photographers
http://www.lightstalking.com/sunny-f16-rule
แปะไว้กันลืมค่ะ
The Life-saving F/16 Rule for Landscape Photographers
photo: Lake Mystic by Tad Cholinski
For a lot of us, landscape photography is one of our favourite past-times. Being out with nature doing the hobby you love, really is something we enjoy.
It can get a little frustrating if we’re not producing the standard of shots that we would like to however.
Luckily, there’s a quick and easy rule that can save your daytime landscapes (or any other daytime shot for that matter), at least in terms of exposure and light.
It’s called the f/16 Rule and is sometimes known as the Sunny 16 Rule.
It’s basically a way of ensuring a reasonable shot under sunny conditions without recourse to a light meter.
The basic rule states to shoot at an aperture of f/16 with a shutter speed of 1/125 when shooting on ISO 100 film.
Or f/16 with a shutter speed of 1/ISO setting (or as close as your camera settings will allow)
For example, let’s say you were shooting on 400 ISO film.
The formula would be f/16 and 1/400 speed.
With ISO 800, it would be f/16 and 1/800 speed.
See also:
http://en.wikipedia.org/wiki/Sunny_16
แปะไว้กันลืมค่ะ
The Life-saving F/16 Rule for Landscape Photographers
photo: Lake Mystic by Tad Cholinski
For a lot of us, landscape photography is one of our favourite past-times. Being out with nature doing the hobby you love, really is something we enjoy.
It can get a little frustrating if we’re not producing the standard of shots that we would like to however.
Luckily, there’s a quick and easy rule that can save your daytime landscapes (or any other daytime shot for that matter), at least in terms of exposure and light.
It’s called the f/16 Rule and is sometimes known as the Sunny 16 Rule.
It’s basically a way of ensuring a reasonable shot under sunny conditions without recourse to a light meter.
The basic rule states to shoot at an aperture of f/16 with a shutter speed of 1/125 when shooting on ISO 100 film.
Or f/16 with a shutter speed of 1/ISO setting (or as close as your camera settings will allow)
For example, let’s say you were shooting on 400 ISO film.
The formula would be f/16 and 1/400 speed.
With ISO 800, it would be f/16 and 1/800 speed.
See also:
http://en.wikipedia.org/wiki/Sunny_16
Sunday, April 3, 2011
Road Trip: The Redwood Highway
Road Trip: The Redwood Highway
In 1912, it took at least two days and a ferry ride to drive from San Francisco to the giant redwoods of northern Mendocino County, traversing some 160 miles of deeply rutted switchbacks and radiator-busting hills. Today, thanks to the Redwood Highway—the northern stretch of U.S. Route 101, which turns 101 this year—in four hours you can get to a tree big enough to drive through. But slow down. Now, as then, the road to (and through) some of the world’s tallest trees is best experienced as a pilgrimage with adventure-worthy way stations. Here are a few of the new and old-time treasures worth pausing for. (All are in area code 707.)
Photography by Peter Buranzon
Link: www.viamagazine.com
In 1912, it took at least two days and a ferry ride to drive from San Francisco to the giant redwoods of northern Mendocino County, traversing some 160 miles of deeply rutted switchbacks and radiator-busting hills. Today, thanks to the Redwood Highway—the northern stretch of U.S. Route 101, which turns 101 this year—in four hours you can get to a tree big enough to drive through. But slow down. Now, as then, the road to (and through) some of the world’s tallest trees is best experienced as a pilgrimage with adventure-worthy way stations. Here are a few of the new and old-time treasures worth pausing for. (All are in area code 707.)
- Solar Living Center Born in the 1970s as a supply shop for back-to-the-landers, this sprawling collective, on the east side of Highway 101 in Hopland, has become mainstream green—while still a source of solar power equipment, advice, and inspiration. Visiting kids love the playground’s solar-powered water feature and carousel—where else can they ride a spawning salmon? The hay bale–insulated homes, demonstration gardens, and informational displays impress even non-hippie grown-ups. Shop for 300-count organic cotton sheets, solar-powered coolers, and camping ovens among hundreds of eco-themed books, games, and unusual gifts. 13771 S. Hwy. 101, Hopland, 472-2450, solarliving.org.
- Grace Hudson Museum Head into downtown Ukiah, near the intersection of South State Street and Clay to explore the bohemian family life of successful 19th-century artist Grace Hudson and her physician-anthropologist husband, John. Today the engaging museum’s collection of intricate Pomo baskets is prized at least as highly as Grace’s paintings of her Pomo neighbors. 431 S. Main St., Ukiah, 467-2836, www.gracehudsonmuseum.org.
- Montgomery Woods State Reserve From the Hudson museum in Ukiah, continue north on State Street to Orr Springs Road, then turn left. The world’s seventh-tallest tree is said to live among these never-logged redwoods, 15 curvy miles northwest of downtown. A few miles of well-tended, fern-fringed trail loop through a boneyard of ancient, hollowed-out redwoods ringed by a cathedral of offspring 300 feet tall. New facilities including picnic tables, parking, and a bathroom were just completed in fall 2010. 937-5804, parks.ca.gov.
- Hot springs On the road back to 101 from Montgomery Woods you’ll pass on the right Orr Hot Springs, a rustic, clothing-optional resort with shade gardens, a communal kitchen and camping area, and a couple of private cottages and yurts, along with the soaking tubs. 13201 Orr Springs Rd., Ukiah, 462-6277. Call for prices. History buffs and those who like their public soaks swimsuit-mandatory may prefer Vichy Springs Resort, a 5-minute drive into the eastern hills from downtown Ukiah along Vichy Springs Road. It has updated rooms and cottages along a creek, plus a pool big enough to swim laps. The main draw: naturally carbonated hot springs and soaking tubs. Nineteenth-century notables including Teddy Roosevelt, Mark Twain, and Jack London enjoyed soaking here, too. Rooms from $105 for AAA members (ask for the February special). 2605 Vichy Springs Rd., Ukiah, 462-9515, vichysprings.com.
- Ridgewood Ranch: Home of Seabiscuit Christ’s Church of the Golden Rule now owns this oak-shaded ranch south of Willits, where legendary 1930s thoroughbred Seabiscuit trained and is buried. Two Saturday mornings a month, from June through October, horseracing fans can visit his restored stud barn and training grounds and meet a few of Seabiscuit’s descendants in a docent-led tour; free guided nature walks are offered in spring. Call or check the Web site for dates and to make reservations. 459-5992, seabiscuitheritage.org.
- Mendocino County Museum/Roots of Motive Power In downtown Willits, turn east off 101 onto Commercial Street. Exhibits include treasure from a 19th-century sailing ship wrecked off the Mendocino coast, a re-created local diner from the 1930s, and a hippie van from the ’70s complete with velvet-draped bed, Turkish rugs, and a stuffed boar’s head. The attached steam/diesel machine museum and library offer tours of mighty locomotives and logging equipment. 400 E. Commercial St., Willits, 459-2736, mendocinomuseum.org and rootsofmotivepower.com.
- Chandelier Drive-Thru Tree Willits calls itself the “Gateway to the Redwoods,” but Leggett, 45 miles up the Redwood Highway, may hold a firmer claim. In the 1930s, one Leggett resident and his friends chiseled a hole in a 315-foot redwood that’s big enough (just barely) to drive through in a Ford Escape. Stock up on redwood tchotchkes in the gift shop—pen sets, yo-yos, music boxes, earrings, and so on—or buy a living redwood seedling. 67402 Drive Thru Tree Rd., Leggett, 925-6363, drivethrutree.com.
- The Peg House Whether you turn for home here or head north into the really big woods, this general store and café, built in the 1960s with hand-hewn beams and without nails, is the place to stop for espresso, grilled tri-tip sandwiches, maté tea, and fresh-baked “mookies” (muffin-cookies). Across the road from Standish-Hickey State Recreation Area in Leggett. 925-6444, thepeghouse.net.
Photography by Peter Buranzon
Link: www.viamagazine.com
Starburst Effects - Photo Tips @ Earthbound Light
Starburst Effects - Photo Tips @ Earthbound Light
Starburst Effects
Turning the sun into a starburst can add a special something to a photograph. Making it happen though can seem like blind luck, but there is a secret to increasing your odds.
The aperture of a lens is formed by an overlapping arrangement of blades that open and close to control the amount of light reaching the film. A spreading of light known as diffraction along the boundaries between these blades at small openings results in the starburst effect. The smaller the opening, the more pronounced the effect.
As was mentioned last week, a lens's aperture number is a ratio between the diameter of its opening and its focal length. As such, if a lens is set to an aperture of f/22, it has an opening with a diameter that is 1/22 of its focal length. Contrary to you might think at first, if you keep the diameter of the opening the same but increase the focal length, the aperture doesn't stay the same. Take a 50mm lens and set it to f/22. Then take a 100mm lens (twice the focal length) and set it so that its opening is exactly the same size as the 50mm lens. The aperture of the 100mm lens would be a ridiculous f/45 (double that of the 50mm lens), in order to maintain the same ratio (50 divided by 22 is the same as 100 over 45). Since there is no such thing (generally speaking) as an f/45 lens for an SLR, you will likely need to settle for an f/22 aperture on that 100mm lens which would be a bigger hole than would f/22 on that 50mm lens.
Sunset on First BeachSo, in order to get more chance of diffraction, you should use a small lens opening, and you will get a smaller opening if the lens you use is a wide angle lens instead of a telephoto, since by definition this will give you a smaller focal length and therefore a smaller lens opening for a given aperture.
The number of streaks in the starburst depends on the number of blades in the aperture. The diffraction occurs at each point where two blades overlap and spreads in both directions from the center of the lens outwards. Lenses that have an even number of blades will yield starbursts that have the same number of streaks as blades since each streak will have a counterpart from the opposite aperture blade that lines up with it exactly. If a lens has an odd number of aperture blades (as most actually do) you will end up with twice as many streaks as aperture blades since no overlap will occur.
As you probably already know, along with all the other "special effects" filters currently available, you can buy so called "starburst" filters, so all this may sound like more bother than it's worth. In my experience though, these filters rarely yield optimal results. They allow you to create starbursts even when they wouldn't normally occur. And wouldn't really rather have the real thing anyway?
Update 12/12/2004: If you shoot with digital, you might not want to go all the way to f/22. Diffraction though that small of an aperture can start to soften an image more on digital due to the smaller sensor size. You can still get great starbursts at f/16 though.
Starburst Effects
Turning the sun into a starburst can add a special something to a photograph. Making it happen though can seem like blind luck, but there is a secret to increasing your odds.
The aperture of a lens is formed by an overlapping arrangement of blades that open and close to control the amount of light reaching the film. A spreading of light known as diffraction along the boundaries between these blades at small openings results in the starburst effect. The smaller the opening, the more pronounced the effect.
As was mentioned last week, a lens's aperture number is a ratio between the diameter of its opening and its focal length. As such, if a lens is set to an aperture of f/22, it has an opening with a diameter that is 1/22 of its focal length. Contrary to you might think at first, if you keep the diameter of the opening the same but increase the focal length, the aperture doesn't stay the same. Take a 50mm lens and set it to f/22. Then take a 100mm lens (twice the focal length) and set it so that its opening is exactly the same size as the 50mm lens. The aperture of the 100mm lens would be a ridiculous f/45 (double that of the 50mm lens), in order to maintain the same ratio (50 divided by 22 is the same as 100 over 45). Since there is no such thing (generally speaking) as an f/45 lens for an SLR, you will likely need to settle for an f/22 aperture on that 100mm lens which would be a bigger hole than would f/22 on that 50mm lens.
Sunset on First BeachSo, in order to get more chance of diffraction, you should use a small lens opening, and you will get a smaller opening if the lens you use is a wide angle lens instead of a telephoto, since by definition this will give you a smaller focal length and therefore a smaller lens opening for a given aperture.
The number of streaks in the starburst depends on the number of blades in the aperture. The diffraction occurs at each point where two blades overlap and spreads in both directions from the center of the lens outwards. Lenses that have an even number of blades will yield starbursts that have the same number of streaks as blades since each streak will have a counterpart from the opposite aperture blade that lines up with it exactly. If a lens has an odd number of aperture blades (as most actually do) you will end up with twice as many streaks as aperture blades since no overlap will occur.
As you probably already know, along with all the other "special effects" filters currently available, you can buy so called "starburst" filters, so all this may sound like more bother than it's worth. In my experience though, these filters rarely yield optimal results. They allow you to create starbursts even when they wouldn't normally occur. And wouldn't really rather have the real thing anyway?
Update 12/12/2004: If you shoot with digital, you might not want to go all the way to f/22. Diffraction though that small of an aperture can start to soften an image more on digital due to the smaller sensor size. You can still get great starbursts at f/16 though.
Friday, April 1, 2011
Neutral Density Filters
Neutral Density Filters by singleservingphoto.com
This is a great and comprehensive, easy to understand guide to Neutral Density Filters.
"Sometimes when you’re shooting in broad daylight you may have a reason to use a longer exposure than you can achieve from your smallest aperture and lowest ISO setting. That’s where neutral density (or ND) filters come in.Click on link above to read full article.
ND filters have been widely written about, so I don’t intend to flog a dead horse here. Still, while shopping for ND filters today, I realized that this whole numerical rating system they use is kind of confusing, and I always wondered why some manufacturers will say ND.3, while others simply write 0.3, and yet others come out and plainly state “one stop.”...
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