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Reverse Lens Technique in Macro Photography


How to save your money and still shoot amazing macro photography images


!How to save your money and still shoot amazing macro photography images


This page is about close-up photography which, in plain words, is all about taking pictures of very small details of the world around us: jewels, stamps, bugs and insects of any sort, flowers, sand, seeds and any other subject you might find interesting.
Even the most common and trivial subjects will look amazingly new and interesting when seen from a very close point of view.
There are many ways to shoot macro images. We will now explore one of the most interesting tricks in close-up photography, known as reverse lens macro photography.

Digital single-lens reflex (DSLR) camera owners can enjoy such an inexpensive technique which allows them to shoot amazing macro photography pictures using the same lens they adopt for general photos. A normal prime lens is a wonderful tool for this. No need to buy macro lens or extra close-up lens, unless you are really involved with macro shots all of your time.
Where is it the trick? Well, it is no secret: just reverse your lens, hold it tight in front of your camera with whatever light-tight material you have at hand (black-tape, hand-made cardboard tube, cloth, ad hoc plastic tube or bellow,…) and shoot!
Let’s see how things work.

Here is what you will find in this very page:


A small reverse lens macro images gallery

Images in this gallery feature high optical quality and crisp details in the in-focus area.
They are all taken by just reversing a standard lens.




Candle wick shot with a reversed lens — Photo by s_karr

Photo ©© s_karr




Some basic tips for better macro pictures

The following tips are part of our page featuring tutorials on how to shoot macro photography the easy way.

  1. Everything will be new and valuable if observed from a close-up perspective.
    Go past your standard way of looking at things. Do not search for extraordinary subjects. Even a simple grain of salt might look absolutely surprising when enlarged enough. There is a new world around you, ready to be discovered.

  2. Use a tripod.
    Make sure that both camera and your subject are firmly set up: prefer a tripod or use any other rig at hand; whenever possible, block your subject with tape, sticks, stones and whatever else you feel appropriate. Also, shield your scene from the wind if you are shooting outdoor. Shoot by a wireless remote trigger in order to avoid touching the camera at all, and lift the mirror before actual triggering the shutter (whenever possible and appropriate).

  3. Both background and foreground might be distracting.
    Have them blurred and cleaned from disturbing elements. Choose the right point of view, shoot and inspect your picture in-camera at once: if required set up a better stage and reshoot.

  4. The easiest way to focus is to move camera back and forward.
    Leave the focusing helix alone. Depending on the situation, moving the subject might be a fine choice as well. Also, as you are shooting digital, consider focus stacking software for enhancing depth-of-field.

  5. Double-check focus. Then check it again.
    At high magnification ratios depth of field is often much shallower than you might like. You should also check a zoomed-in image just after your shot. Checking focus more than once both before and after shooting is good practice.

  6. Light is a key factor: light your scene appropriately.
    Avoid too harsh contrast. Use flashes, reflectors, diffusers, and do not forget that, although tiny, your subject deserves the same care as any other model does. Remember that exposure is often tricky. Check exposure both before and after shooting. Bellows extension exposure compensation has to be taken into account if required.

  7. Do not use high Iso settings.
    Keep your sensor/film speed low. Grain will spoil your macro pictures, definitely. Shoot Raw format if you can. Bracket exposures.


Why you should flip your lens, explained in two simple steps

General lenses are designed to have something far in front of them, and something quite close at the rear side.
This is usually the case when shooting mountains: mountains are far in front of the lens, and sensor is close at the rear side.
If you want to place a flower close to the lens, you’ll then have to put it in front of the rear glass and let the sensor be far in front of the front glass.
Which means that you’ll have to flip your lens.
Let’s see more:

1. Focusing distant subjects

Lens is close to the sensorMountain - a far away subject
We use here an old-style bellow camera to show you how things work: you can see the lens in front of the bellow and the sensor plane at the back side. Focusing is manually set by changing the sensor-to-lens distance.

General purpose lenses are designed to offer the best optical performance only when focused at medium-to-long distances. That is, they are good at photographing subjects like: the moon, distant landscapes, family holidays at the seaside, birthday cakes and party guests, corn fields, trees and any other general view.

When focusing on such distant subject, the lens is positioned very close to the sensor.

The further the subject from the lens, the nearer the lens to the sensor. Any subject focused at infinity, just like the moon or a mountain, will cause the lens to be placed at the minimum possible focusing distance from the sensor for that lens. Such distance is equal to the focal lenght of that lens.

2. Focusing close-by subjects

Lens is far from the sensorFlower - a very near subject
What we wrote above is a basic rule of optics and the interesting thing is that, predictably, the reverse applies when the subject is instead focused close to the lens: the sensor will have to be placed at a remarkable distance from the lens. That’s the way optics goes.

When focusing a nearby subject, the lens is positioned far from the sensor.

As written above, general purpose lenses are designed to offer the best optical performance only when focused at medium-to-long distances: that is, the best optical performance is attainable when there is much distance in front of the front lens and small distance in front of the rear lens. Such a behaviour leads to a simple thought: why not reversing the lens, a normal, plain, prime lens, in order to get the best out of your lens when shooting macro? This way your lens is optimized for greater-than-life size shots.


So, it’s time to flip your lens now

Take a prime lens, turn it back-to-front and tape it to the camera (or you might want to use a reverse lens mount adapter instead).1 You are likely to loose most (or all) of the automatic settings that your digital camera would have set for you2 3. Do not worry. Move back and forth until you have your subject (a very close one, do not forget) in focus, and then shoot! You will be surprised of how good your picture is.
This is because you are using your lens right in the way it is calculated for.

Warning: as macro photography is all about placing your lens quite close to the subject, extra care should be taken not to hit the lens glass, because it may damage. This is particularly true as you reverse your lens, in that a scratch in the rear lens risks to be a real loss in image quality (not to mention lens value), whereas a similar scratch on the front glass does not usually spoil your photos that much. Also, the issue is much more important with short focal lenses (wide-angle) as opposed to long lenses.

No need to say that both meter and aperture couplings are lost as flip your lens. This should be no problem, as you can shoot some test pictures and judge exposure out of them.
The difficult part is to set the right aperture: both electronic and mechanical couplings are unuseful here. There are many workarounds how to deal with this issue. For mechanical apertures, one of them is just to set an average aperture4, say something around f/11. You should not use too small apertures, a diffraction may be too bad.

The lens can be kept in place by means of black tape or, more professionally, of a reversing ring which is made just for that. You can buy reversing rings for almost any current lens for a few money.

One can either tape or screw the reversed lens directly to the camera body or place it at some distance by means of an extension tube.
Extension tubes are sold by any photo dealer, or can be home made with plastic, cardboard or any other suitable material and keept all together with black tape. Such a solution allows you to create wonderful pictures at almost no cost.
A variation worth considering on this subject is stacking a prime reversed lens on top of a longer lens (could be a zoom as well).




 

1 Black paper tape is fine enough for the first tests. (↑)

2 Be advised that most of the digital cameras will not allow any metering when the lens is reversed: you will have to make some calculations or some test in order to set the right exposure. (↑)

3 Aperture in electronic digital cameras can often be set by: a) mounting the lens as normal; b) setting aperture; c) pressing the depth-of-field preview button; d) then reversing the lens (↑)

4 General lenses are designed to give best performance at about a couple stops above the fastest aperture. (↑)




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