Saturday, 30 November 2013

Using Axial Lighting for Photographing Coins


Axial lighting is ideal for photographing coins; with it there are no actual shadows, only brighter and darker areas, depending on how much light is reflected back to the camera.

Here’s my setup for photographing coins using axial lighting.


Coin Photography Tutorial
Coin Photography Tutorial


The setup is very easy to make, make a foamcore box, keep one of the sides and top open,  line rest of the box with black velvet (it absorbs stray light preventing unwanted reflections and increasing contrast). Mount a thin piece of glass in it at a 45-degree angle and you are ready to roll.

The camera is mounted on a copy stand, aimed down into the open top of the box.

When light is shined from the open side of the box, it strikes the glass and is reflected down to to the coin which rests on the bottom. The effect is as if the light were coming directly from the axis of the camera lens.

The photo given below shows the results of this lighting...


How to photograph coins
How to photograph coins


With this lighting, any surface perpendicular to the lens reflects the light brightly. Any surface angled away from this axis shows up as increasingly darker.

The light in this case is a focused LED flashlight. The narrow beam also helps to avoid stray reflections. The important thing to remember is to place the light parallel to the sensor plane.

Coin Photography - Axial Lighting Setup
Coin Photography - Axial Lighting Setup


If you are using continuous light sources it is much easier as you can change the tilt angle of the glass and observe the lighting change and thus find the best lighting that suits your need.

To check the angle of the light, substitute a small, flat mirror for the coin. The light should be bright and clearly visible in the viewfinder of the camera.

Enjoy: Jim Salvas

Related Reading


  1. Infinity Focusing – What is it? How does it work? How to manually set a lens without a distance scale to Focus on Infinity?
  2. DIY Flash Extender for Macro Photography
  3. Relationship Between F-Stop Numbers and the Size of the Diaphragm Opening Explained
  4. Making Sense of the Odd Progression of the F-Stop Scale?
  5. Complete Guide to Choosing Macro Lenses

Friday, 29 November 2013

Infinity Focusing – What is it? How does it work? How to manually set a lens without a distance scale to Focus on Infinity?

Infinity Focusing
Infinity Focusing

What does Infinity Focus Mean?


In photography, infinity focus is when the lens forms a sharp image of an object an infinite distance away from the camera.

How Does Infinity Focus Work?


Infinity is the distance from which light rays striking the lens appear as parallel rays rather than diverging rays. Therefore when you are focused at infinity any objects located farther from the point of focus would also be in acceptable focus, there is no need to adjust focus.  Thus Infinity on a camera lens is a point at which no more adjustment needs to be made for objects that are further away to be in focus.

The reason why this work is because when the camera lens is focused at a point very far away; the lens perceives the light rays as parallel rays as it is unable detect any further narrowing of the angle of the beams of light being focused. So anything from infinity onwards will be in focus as far as the lens is concerned.

When would I want to use infinity focus? What's its purpose?


Infinity focus is used for when shooting something that is hard to focus on especially at night or in dimly lit situations.  Examples would be fireworks, a lightning storm (way off in the distance), astrophotography or distant landscapes.

How to focus at infinity?


Some lenses feature a distance scale and they have this infinity symbol printed on them. It is easy to set these lenses to infinity as all you have to do is align the focus to the infinity symbol.  This is usually done by turning the lens focusing ring either all the way to the right or all the way to the left. As usual Nikon and Canon lenses work in opposite directions to each other.

Beware Some Lenses can Focus Beyond Infinity



How to Focus at Infinity
How to Focus at Infinity


Yes it is true some lenses could indeed focus beyond infinity. This is found mainly on moderately new lenses. The reason why lenses could focus beyond infinity is because the point of focus changes with amongst other things the temperature of the lens. So this feature is helpful to get accurate focus even if high temperatures distort the lens and shift the infinity focus-point.

Another reason for making lenses with travel beyond infinity is to make matters easier for the lenses auto focus mechanisms as additional travel beyond infinity makes sure that the AF motor will not bump against a hard stop while attempting to focus on infinity. This is reason why most Canon lenses go past the infinity mark.

For all lenses that just stop sharply at infinity setting infinity focus means to turn the focusing ring all the way to the right or the left (depending on camera make). Pay attention to the type of lens you are using if you are using a lens that could go beyond infinity you might need to turn the focusing ring all the way to the right or left (depending upon your camera make) and pull back the focus slightly to get it right at infinity.

How to manually set a lens without a distance scale to Focus on Infinity?


It’s much easier than you expected'

if its day time, just point the camera towards a distant object, a tree, post, or even clouds and let the camera auto focus. Once focus is achieved either lock focus or shift the lens to manual focus.

If it’s dark find a distant light source and focus on it, you could always use the moon if its visible, modern cameras auto focus systems are so good that they could easily focus on the planets or even the stars.

If in doubt, point your camera towards any distant light source, shift to live view, zoom your LCD display and turn focus ring till you get the light source in perfect focus.

Zoom Lenses and Infinity Focusing


One thing to remember while using infinity focusing on zoom lenses is that there are two types of zoom lenses Parfocal and Varifocal.


Parfocal Zoom Lens
Canon EF 24-70mm f/2.8L II USM - Parfocal Zoom Lens


Parfocal lenses do not shift focus when the focal length is changed. So once you have set a parfocal zoom lens to infinity you need not re adjust it even if you zoom in or out.

Varifocal Zoom Lens
Canon EF 24-105mm f/4 L IS USM - Varifocal Zoom Lens


Varifocal zoom lenses focus at infinity at different positions on the focus mechanism depending on the focal length selected; so if focal distance is changed you need to re  adjust the focus.

Related Reading


  1. DIY Flash Extender for Macro Photography
  2. Relationship Between F-Stop Numbers and the Size of the Diaphragm Opening Explained
  3. Making Sense of the Odd Progression of the F-Stop Scale?
  4. Complete Guide to Choosing Macro Lenses
  5. DIY Flash Modifier

Thursday, 28 November 2013

DIY Flash Extender for Macro Photography


Anyone who has tried shooting close up or macro using the pop up flash on top of the camera might have encountered this problem at some time. When working distance is very small (usually in millimeters with high magnification) the lens blocks the light from the flash, casting a shadow of it on the subject and ruins the shot. This is more pronounced with longer lenses or with a close up attachment, as I had fitted here.


diy flash extender
diy flash extender


In the example given above the first picture (on the left) is taken using our diy flash extender and the one on the right is taken without it.

A quick fix solution to the problem is to extend the flash forward, so it provides light near the end of the lens. To extend the flash what I have used is a simple disposable paper coffee cup attached to the pop-up flash. This brings the light source forward and by leaving the domed plastic cap on the cup, provides a diffused light source close to the end of the lens.

This is how the set up looks.


diy flash extender for macro photography
diy flash extender for macro photography


Our diy flash extender is made from a paper coffee cup, cut a hole on the side of the cup near the bottom. The hole should only be large enough to let the pop up flash head in.

Probably worth mentioning, I have not used anything other than gravity to hold the cup on the camera here. In a studio situation, nothing more is really needed. But if going out and about, a couple of rubber bands will hold it in place. I use one around the base of the cup and hooked under the eyecap on the viewfinder, with a second around the lens and cup.

When we compare the 2 shots there are some obvious side effects to our techniques. Firstly, the amount of light is reduced, which is not such a bad thing when working in this close as you have plenty of flash power. The second is that due to the reduced light and the fact that the light is passing through the plastic lid of the cup, there is also a strong color cast to the picture. This is easy to fix by setting a custom white balance to match the light, or in editing afterwards; no big deal if you shoot RAW. I left it unaltered here to show the effect.

For longer lenses you will need some attachment that is longer enough to get the light where you need it (a Pringles can could be a good choice if you could find a way to cut through the metal base of the can).

Have been playing a bit more with extending the pop-up flash for close up work and decided to do a comparison between using a paper coffee cup and a Pringles tube version.


diy flash extender for macro photography using pringles can
diy flash extender for macro photography using pringles can


Hopefully this shot shows how simple this is to do. The only modification required to the Pringles tube, is to cut a hole for the pop-up flash to fit into. On my Canon, the hole is a 45mm by 20mm rectangle, though you might need to vary this for different cameras. Then it just slots onto the top and is retained at the rear by a rubber band which is hooked under the rubber eye cup on the viewfinder to hold it securely in place.

As can be seen, this is a bit long for use with the 18-55mm kit lens on the camera and for really close macro work, may cause problems. A little further away though, it works fine, as can be seen below.


pringles can macro diffuser result
pringles can macro diffuser result

A giftwrap ribbon rosette being used as a test subject for an extender on the cameras pop-up flash. This one is taken with a Pringles tube placed on the flash to bring the light source forward and diffuse it.This prevents a shadow being caused by the cameras lens when working in close and also softens the shadows which are typical when using the on-board flash. It should be noted, that the addition of the tube does introduce a very slight hint of color to the image, but that is easily dealt with by using a custom white balance setting, or correcting in editing which was done here. The color shift is less with the Pringles tube, than with the paper cup version of this.

Also shown below, is a similar shot taken with a paper coffee cup version of the extender for comparison.


paper coffee cup macro flash diffuser result
paper coffee cup macro flash diffuser result


Hopefully this will be useful to some of you. 

Steve Bennett

Related Reading


  1. DIY Flash Modifier
  2. DIY Flash Diffuser for Macro Photography Made from Coco Cola Cans
  3. How to Make a DIY Ring Flash Video Tutorial


Wednesday, 27 November 2013

Relationship Between F-Stop Numbers and the Size of the Diaphragm Opening Explained


After we published this article Making Sense of the Odd Progression of the F-Stop Scale? I got a handful of e-mails mainly asking doubts like;

  • Do f-stop numbers represent a specific size of lens opening?
  • Do all lenses set to a specific aperture let in the same amount of light? etc

So in this post we will discuss the relation between f-stop numbers and the actual diaphragm openings.

What is a Diaphragm?



Iris Diaphragm
Iris Diaphragm animation courtesy: Wikipedia


In photography, a diaphragm is a device that controls effective diameter of the lens opening and is called the “aperture” or “iris” of the lens. Diaphragm is located within the lens and is made up of a series of metal blades that form a circle. The adjustable diameter of the aperture is how the camera regulates the amount of light that pass through the lens to the sensor.

How are F-Stop numbers and Aperture Diameters Related?


The formula to find f-stop is:

f-stop = focal length / diameter of lens opening


What are F-Stops?


F-stops are a measure of the aperture of a lens; they express the ratio of focal length to apparent lens aperture. F-stops tell us how wide the opening of the iris is.

What is Focal Length?



Focal Length
Focal Length


Focal length of a lens is the distance between the optical center of the lens and the sensor plane.

So when trying to figure out the actual diameter of the diaphragm opening we should also consider the focal length of the lens in addition to the f/number.

f/2 = focal length / 2 
f/4 = focal length / 4 
f/5.6 = focal length / 5.6 and so on.

Let us try the formula on two different lenses one a 50mm and another 100mm.


Canon 50mm f/1.8 and Canon 100mm f/2.8 both set to f/2.8
Canon 50mm f/1.8 and Canon 100mm f/2.8 both set to f/2.8


f/2 for a 50mm lens will be a lens opening of 25mm. (50/2). And
f/2 for a 100mm lens will be a lens opening of 50mm. (100/2).

It is clear that when the focal length increases so does the diameter of the diaphragm. In this case when focal length increased from 50mm to 100mm the size of the diaphragm doubled from 25mm to 50mm.

But to determine the amount of light reaching the sensor shouldn’t we be considering the area of the circle instead of its diameter.

Let us have a look our two lenses, the 50mm and the 100mm

The 50mm lens when set to f/2 has a diameter of 25mm or radius of 25/2 = 12.5mm and
The 100mm lens when set to f/2 has a diameter of 50mm or radius of 50/2 = 25mm.

Applying the formula A=πr^2 (read π r squared)

The area of our 50mm lens set to f/2 will be 3.14 x 12,5² = 490,6 mm² and
The area of our 100mm lens set to f/2 will be 3.14 x 25² = 1962,5 mm²

From the above example it is clear that at an aperture of f/2 the 100mm lens has a diaphragm opening which is 4 times bigger than the 50mm lens which is also set to f/2 (1962.5 / 490.6 = 4).

Why is the Aperture area 4 times bigger when the focal length is doubled?


The aperture is 4 times bigger because the area varies in relation to the square of the radius. So doubling the radius is the same as saying 2² which is 4.

How does two diaphragm sizes one 4 times bigger than the other let in the same amount of light?


It might sound confusing at first but the answer to this question lies partly in mathematics and partly in physics.  First focal length plays an important role in deter mining the amount of light and then there is the Inverse Square Law.

Inverse square law



Inverse Square Law image courtesy: Wikipedia


Inverse square law states that some physical quantity or strength is inversely proportional to the square of the distance from the source of that physical quantity.

To put matters simply as per Inverse square law, the power of the light will be inversely proportional to the square of the distance.

For example

When a distance of 2 is squared we get 4 the inverse of which is ¼. Meaning when light travels double the distance the power of light is reduced to ¼.

Summing Up


To conclude let us state some bare facts.

  1. F-stop numbers does not refer to any particular size of aperture it is the ratio of focal length to apparent lens aperture.
  2. Same f-stop number when set on different focal length lenses will have different diaphragm sizes.
  3. Same f-stop numbers set on different lenses will let in exactly the same amount of light irrespective of the size of their aperture opening.
  4. At any aperture when focal length is doubled the size of diaphragm increases 4 times.

Related Reading


  1. The Sunny 16 Rule for Macro
  2. Macro Photography - Seven Secrets for Stunning Macro Shots
  3. Macro Photography – Gearing Up for Macro Perfection
  4. Macro Photography Subjects - Seeing Everyday Objects in Macro
  5. Macro Photography – Light It Right

    Tuesday, 26 November 2013

    Making Sense of the Odd Progression of the F-Stop Scale?


    We all know that aperture of a lens is marked with f/stop numbers that work in stop values where numbers in the progression represent doubles and halves. If you look at a standard f/stop series the values are:

    f/1, f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22 and f/32.

    It is clear that the numbers themselves are not doubles and halves then on what basis are these values used.


    Aperture
    Aperture


    Why such a weird progression of numbers?



    Area of a Circle
    Area of a Circle


    The f/stop sequence represents the varying hole size in a lens (the aperture) through which light passes. Each aperture allows twice as much or half as much light to pass as the preceding or following aperture. The aperture is in the shape of a circle and to make each aperture double or halve the amount of light the area of the circle should be doubled or halved. F-stop numbers are actually fractions and thinking of them as fractions is the easiest way to understand why the larger numbers represents smaller lens openings and vice versa ( ½ is a lot larger than 1/22). Thus f/2 represents a fairly large hole that admits a lot of light while f/22 is quite a small opening admitting only a small amount of light.

    If you look closely at the aperture scale you will find that each number is 1.4 times the preceding.


    Since apertures are holes in the lens which is circular in shape we could use the following formula to calculate the area of a circle.

    Area of a Circle (A) = πr^2  (kindly read "r^2" as r squared)

    Where A = Area, r = radius, π = 3.14

    So 2 πr^2 = πx^2. Solve for x and you get the square root of 2 (which is 1.414) times the radius.

    For example


    Lens Aperture
    Lens Aperture


    Let us assume that at a given aperture the size of the lens opening (read area of the circle) is 3.14.

    i.e πr^2= 3.14 that translates to 3.14 x r^2= 3.14 so r^2= 3.14/3.14 = 1. Therefore r = √1 = 1.

    so we have a circle with an area of 3.14(mm or cm or any other measure) and a radius of 1 (again any measure).

    Now let us see what happens when we double the area of the circle.

    New area = 3.14 x 2 = 6.28 now let’s find out the radius of our new circle

    6.28 = 3.14 x r^2 i.e. r^2 = 6.28/3.14 = 2 therefore r = √2 = 1.4

    Thus it is clear that the diameter varies as the squared root of the area. When we double the area the diameter will be 1.4 times (which is √2 )  larger and that is how the aperture scale is built using the multiplication function.

    f/1 x 1.414 = f/1.4
    f/1.4 x 1.414 = f/2
    f/2 x 1.404 = f/2.8
    f/2.8 x 1.414 = f/4 and so on….

    Wow the f stop sequence of numbers.

    Monday, 25 November 2013

    Complete Guide to Choosing Macro Lenses


    Macro Lenses
    Macro Lenses


    What is a macro lens?


    There are many lenses out there in the market which have a symbol of a small flower indicating macro. However those lenses are not macro lenses in true sense. In order to qualify as a true macro lens it should be able to produce life size (1:1) magnification on the camera sensor. Any lens which is capable of reasonable subject magnification but is not capable of achieving 1:1 is called close up lenses and not macro lenses.

    What is Life Size (1:1) Magnification?


    Magnification or magnification ratio is the ratio between the size of the subject (in focus at the closest focusing distance) and its size on the image sensor. So if a subject measuring 1cm in reality appears the same size in the sensor it is called life size or 1:1 magnification.


    Lens magnification
    Lens magnification


    If an object is 100cm in reality but its projected size is only 1cm on the image sensor then magnification of the lens will be 1cm/100cm or 1/100. Similarly if a subject that is 10cm long and its projected size is only 2cm on the image sensor then the lens magnification will be 2cm/10cm or 2/10.

    Magnification of lenses is notated using a colon; so the above examples will be noted as 1:100 and 2:10 respectively.

    A ratio of 2:10 means that in reality the subject is five times larger than its projection on the image sensor.

    Macro Lenses are Flat Field Lenses


    Generally all lenses except macro lenses are curved field lenses and images shot with them will have a field curvature; meaning the point of focus will be slightly different at the corners than the center. 
      

    Flat Field Lens
    Flat Field Lens


    In the illustration given above first one is a normal lens which has a curved field and as a result if you focus the lens on the green star in the center, then the stars on the corners will be out of focus due to the field curvature of the lens. If the stars were in the position indicated by the red stars then they would be in focus too.

    The second lens in the illustration is a flat field lens and you could see that all the three stars, the one in the center and those towards the corners are all in sharp focus. This is extremely important when photographing small objects such as postage stamps as we need to get both the center and corners in sharp focus.

    Having a flat field lens might not be that important for other types of photography, some genres of photography like portraiture could actually benefit from a little field curvature and in certain situations it is also possible to reduce the side effects of field curvature by stopping down the lens to a narrow aperture. But this is not possible in all situations and depending on the lens you're using and how close the lens is to your subject, the edges might still be soft even after you stop down to smaller apertures.

    Magnification and Sensor Size


    Before going into details let us first clarify one important point which many people often confuse; when we talk about magnification of macro lenses we are actually referring to the magnification at the sensor plane and not about the size of the image on a print or when viewed on a computer screen.

    Another important point of confusion is the size of the sensor and how it effects lens magnification. The truth is that the lens magnification remains the same irrespective of the size of the sensor used to capture images. A lens focused at a certain distance produces an image circle of a certain size at the image plane; this does not change when the lens is mounted on a full frame camera or on a crop sensor camera. The only difference is that the crop sensor only captures the center portion of the image cropping away the rest.

    Does this mean magnification obtained is the same when a lens is mounted on a full frame camera and on a crop sensor camera?


    Full Frame Camera Sensor Vs APS C Camera Sensor
    Full Frame Camera Sensor Vs APS C Camera Sensor


    No even though the actual magnification produced by the lens at the image plane remains the same you will get more magnification when it is mounted on a crop sensor camera than when used on a full frame camera.

    For example:

    A 100mm macro lens set to 1:1 magnification will project an image in life size on the sensor plane. So if a subject measuring 15mm is shot at the same setting using the same lens set to 1:1 but using two different cameras, one a full frame camera and another a crop sensor camera, the full frame camera will be recoding an image which is 15mm on a sensor that is 24mm x 36mm in size, the subject will be half the height of the sensor. But on a crop sensor camera with a sensor size of 15.7mm X 23.7mm the 15mm subject will fill most of the frame. So for practical purposes, you do get more magnification with the smaller sensor, the subject fills up more of the image frame.

    Macro Focal Length


    Generally macro lenses are grouped into three heads according to their focal length, they are:

    • Normal (macro lenses with focal lengths of 50mm – 60mm)
    • Short Tele Photo (macro lenses with focal lengths of 90mm-105mm) and
    • Tele Macro  (macro lenses with focal lengths of 180mm-200mm).


    The major differences between these lenses are in their working distance and perspective. The longer the focal length, the greater the working distance and vice versa. 1:1 magnification will be achieved by a 50mm lens at a distance of approximately 8 inches where as a short tele macro will achieve the same magnification at around 12 inches and a tele macro at 19 inches. 

    Macro Lens Focal length and Working Distance
    Macro Lens Focal length and Working Distance


    Remember in macro photography especially of live subjects (read skittish insects) working distance is often crucial to getting the shot, longer working distance also makes lighting the subject much easier. Now about perspective shooting closer to the subject expands perspective, while shooting from farther away compresses it. so shorter focal lengths provide an immersed feel but reduces chances of getting the shot, longer focal length lenses compresses the perspective thereby producing flat images but the longer working distance greatly increases your chance of getting the shot.

    However when selecting the focal length required you should also consider some other factors, one is the crop factor of your cameras sensor. An APS-C sensor with a crop factor of 1.5x or 1.6x will turn the above macro lenses into 75mm, 150mm and 300mm respectively.

    Cross Compatibility


    All macro lenses designed to be used with full frame cameras could also be used with APS-C cameras but not all lenses designed for APS-C format could be used on full frame cameras. For example APS-C-format Canon lenses can't be mounted on full frame Canon DSLRs; APS-C-format Nikon lenses can be mounted on full-frame Nikon DSLRs, but the camera will crop the image to DX format; APS-C-format Sony lenses can be mounted on full-frame Sony DSLRs, but will vignette; APS-C-format Sigma, Tamron and Tokina lenses are for APS-C-format DSLRs only; all Pentax DSLRs (except the new 645 medium-format model) are designed for APS-C sensors.

    So before choosing a particular lens (especially the one’s designed for APS-C cameras) think ahead, if there are chances that you will upgrade to a full frame system in future then it is recommended you go for lenses designed for full frame cameras.

    Internal Vs External Extension


    Lens elements are closest to the sensor when the lens is focused to infinity and they are farthest from the sensor when the lens is focused at its closest focusing distance. Achieving life size magnification requires the lens elements to move a considerable distance away from the sensor. In case of older lenses the front element will extend further forward as one focus closer and closer, this is very inconvenient as the lens could cast its shadow on the subject or even accidentally strike the subject while trying to focus. Modern macro lenses have Internal extension, here the lens does not extend forward as one focus closer instead it’s the inner elements that move to achieve focus.  This also allows for a closer minimum focusing distance and a more compact lens design as the internal elements are both considerably smaller and lighter than the front element; this also makes things easier for the AF motor, resulting in quicker auto focus.

    Macro Lenses - Auto Focus and Image Stabilization



    Canon 100mm f/2.8 IS USM Macro Lens
    Canon 100mm f/2.8 IS USM Macro Lens


    There are some macro lenses like the Canon 100mm f/2.8 IS USM which feature Canon’s ‘Hybrid’ optical image stabilization system designed to compensate for two distinct types of camera shake. Which not only detect and correct changes in the angle the lens is pointing by also compensates for vertical and horizontal shifts in the position of the lens caused by handshake. This has little benefit at long focusing distances, but as the subject gets closer and closer it becomes progressively more important.

    Photographers are divided on their opinion about the usefulness of autofocus and image stabilization at high magnifications. But my personal experience is that a macro lens such as a 100mm is not always used at 1:1 in fact most of the shots are taken at far less magnifications and when working in the field at less than ideal lighting conditions. I find both auto focus and image stabilization quite useful and is worth the extra money that you need to pay.

    So to conclude when choosing a macro lens, consider the following points:

    1. Amount of magnification required.
    2. Type of use (whether moving or stationary) this dictates the working distance and thus the focal length of the lens. (also consider sensor size when deciding focal lengths).
    3. Full Frame Lens Vs APS-C (if chances are you will upgrade to a full frame camera, choose a full frame lens)
    4. Image Stabilization & Auto Focus
    5. Lens Extension - Internal Vs External Extension

    Related Reading


    Sunday, 24 November 2013

    DIY Flash Modifier

    My Ghetto Flash Modifier

    In my quest to get light onto macro subjects without carrying a lot of gear in the field or spending a bundle on a macro flash setup, I have come up with this, which I call MuzzBounce™ because I'm silly like that.

    The main problem with using an ordinary on camera external flash and macros is you can't get the flash to hit the subject.The working distances with this macro lens are very close, so even if I could get the flash aimed at the subject without the lens casting a shadow (I can't: the flash doesn't point down that far) it would be way too bright at any setting.

    Here is my first try at a cheap solution.

    Step 1



    diy flash modifier
    DIY Flash Modifier


    First, I found an ordinary translucent white plastic jug. This one used to contain windshield wiper fluid.

    Step 2



    DIY Flash Diffuser
    DIY Flash Diffuser


    I cut off the top, leaving a cylinder with a closed bottom. In the very center I placed the flash, marked the 4 corners with a pen, and cut an "X" slightly larger than the flash dimensions for an easy fit, and stuffed in the flash. The fit is firm... no wobbling. Take care when removing the flash not to break the retractable diffuser screen if your flash has one.

    Step 2: Another View



    diy flash diffuser milk jug
    DIY Flash Diffuser


    An alternate view. The plastic on the bottom of the jug is quite firm and the device fits snugly on the flash.

    Step 3



    DIY Flash Diffuser
    DIY Flash Diffuser


    Next, I cut down the cylinder at about a 45 degree angle. The angle is important... eyeball it with it mounted on the camera. in my case, I cut it 90 degrees off axis by mistake. Luckily, my flash unit swivels horizontally, so I'll get my light from above and to the right, which might be useful sometimes. Next time I make one of these, I will cut the 45 degree angle correctly so that the light will bounce from above. (You'll understand when you see the final product picture)

    Take the cut cylinder and trace around it on a piece of corrugated cardboard. Cut out the cardboard and glue some white paper on one side to make a reflective surface.

    Attach the cardboard to the end of the cylinder with the paper side inside, of course. I used duct tape to preserve the ghetto appeal


    DIY Flash Diffuser
    DIY Flash Diffuser


    As you can see, I messed up the 45 degree cut off by a quarter turn. Fortunately my flash swivels. Rotate the cut counterclockwise (in this image) 90 degrees and you won't have to swivel the flash to aim the light on the subject.

    What you end up with is a lot of relatively diffuse light very close to the front of the lens... perfect for very close focus distances.

    (Oh, and sorry about the white balance on this point and shoot picture.)

    How well does it work? It works very well indeed, considering the cost. The following two images are just my first tries, just to show an couple of examples, not for any attempt at art.


    DIY Flash Diffuser Review
    DIY Flash Diffuser Review
    My dog's iris with home made flash modifier.

    1/80th sec f/13 ISO 100 in a darkened living room

    DIY Flash Diffuser Review
    DIY Flash Diffuser Review
    Icky nail shot with home made flash modifier. Note the lack of harsh shadows and specular highlights.

    1/80th sec f/16 ISO 100 in fading afternoon light

    Have you tried something similar, if not do give it a try and if yes post yours in the comments below, we would all love to see them. 

    Eric

    Saturday, 23 November 2013

    DIY Flash Diffuser for Macro Photography Made from Coco Cola Cans


    DIY Flash Diffuser for Macro Photography Made from Coco Cola Cans
    DIY Flash Diffuser for Macro Photography Made from Coco Cola Cans


    Having used the same diffuser for about 18 months (made from plastic milk bottle duct tape and kitchen towel) decided to try and make a new one with the aim of making it more light efficient; so I didn't have to wait for the flash to recharge when taking fairly quick sequences of shots.

    As I needed something with a fairly shiny surface decided to see what I could do with a couple of coke cans :)

    Finished prototype (lot of duct tape involved :)


    diy diffuser for macro
    diy diffuser for macro

    how to make diy diffuser for macro
    how to make diy diffuser for macro


    Just kitchen towel over the front at the moment

    Note you need to be careful making this- very easy to cut yourself on the edges of the tin.

    Ingredients- 2 empty drinks cans, duct tape, stapler, kitchen towel, scissors

    Carefully cut the bottom and top off the cans- I made a slit with a sharp knife and then just used scissors to trim any sharp bits off the edge.


    how to make a diffuser for macro photography
    how to make a diffuser for macro photography


    Then make cuts from one edge up to within about 2cms of the other edge with the strips about 1.5cms wide (the strips in the picture are a bit too narrow).


    Macro Flash Diffusion
    Macro Flash Diffusion


    Cut several strips of duct tape about 1cm wide and have them ready. You then overlap the strips on the bottom edge one over the other (think the technical term is gathering) overlapping each one about half the width and when you have done about 5 stick them in place with the strip of tape and then continue round the whole piece of tin. Do this for the second tin as well. Fold over the edge with the cuts in at about 60' with about 2cms length.


    DIY Flash Diffuser for Macro Photograghy
    DIY Flash Diffuser for Macro Photograghy


    When you have done both tins stick the two halves together with a slight overlap and staple as well if necessary. At this stage it's a good idea to put duct tape over the sharp edges to stop any cuts. You should now find you can wrap the construction around the flash head- and temporarily stick the other edge with probably a large overlap together with duct tape. 

    Take it off the flash and trim off most of the overlap and stick together with duct tape and staples if necessary. I covered the entire outside with duct tape and then just sellotape a piece of kitchen towel over the front.

    macro photography flash diffuser
    macro photography flash diffuser

    Here are a couple of shots taken with this diy diffuser.


    How to Make a Cheap DIY Flash Diffuser for Macro Photography
    Photo by: Brian Valentine

    Best flash diffusers
    Photo by: Brian Valentine


    Brian Valentine

    Friday, 22 November 2013

    How to Make a DIY Ring Flash Video Tutorial

    In this tutorial we will discuss how to make a ring flash for your dslr camera which is extremely useful for macro work. It is made out of an aluminium shop light shade. Here's a picture of the finished product.


    DIY Ring Flash
    DIY Ring Flash

    List of Materials needed for making DIY Ring Flash


    1. One 4"-5" galvanized vent reducer (coupler) available at home depot costing approximately $6.
    2. One aluminium shop light shade (10 1/2" clamp reflector light) available at home depot for about $10.
    3. One 1 1/4" galvanized bar stock 3 feet approximately $7 (1-1/4" x 1/8" x 36" metal bar).
    4. roll carpet tape (heavy duty double sided tape)
    5. double sided foam tape roll
    6. 1/4" thumb screw to fasten camera
    7. 3/16" screws, nuts and lock washer/washers to fasten bracket to reflector
    8. JB weld epoxy
    9. fabric tape to cover flash hole rough opening
    10. flat balck spray paint and primer
    11. michael's fun foam 8 1/2" x 11" sheet (black)
    12. Chefmate cutting mat 4 pack for flash diffuser


    Tools Required for making DIY Ring Flash


    1. Dremel
    2. Hacksaw
    3. Drum sander
    4. Sand Paper
    5. Scissors
    6. Marker
    7. Steel Pop Rivets
    8. Tin snips / Meal Sheers


    Here's the first part of the video tutorial





    And here's part 2





    Notice the extra layer of diffusing material at the 5 to 7 o-clocked position (in the picture given below). This is due to the flash head entering the 6 o-clock position thus creating a hot-spot.

    DIY Ring Flash Tutorial
    DIY Ring Flash Tutorial

    Here's a picture from the construction phase.

    Ring Flash - DIY Photography
    Ring Flash - DIY Photography

    And finally some shots taken with the diy ring flash for your inspiration.

    diy ring flash for your dslr
    diy ring flash for your dslr
    diy ring flash strobist
    diy ring flash strobist
    diy photography ring flash
    diy photography ring flash
    DIY Ring Flash Video Tutorial
    DIY Ring Flash Video Tutorial
    How to Make a DIY Ring Flash
    How to Make a DIY Ring Flash
    Have Fun: Roy Niswanger