Close-up Filters for Flower Photography
by Lindsay Dobson Photography
Close-ups of flowers, plants & insects
The term ‘close-up photography’ means anything which is close enough to show more detail than we might see with our eyes. Macro photography on the other hand defines an image where the size is the same or greater than the size of the subject.
The term “macro photography” can mean different things to different people. The accepted definition is that true macro photography will render the subject at not less than a 1:1 ratio (actual size). ‘Close-up’ photography on the other hand is a broader term describing anything where there is a degree of magnification in your image.
If you enjoy flower photography then chances are you’ll enjoy capturing close-ups of your favourite blooms. This might be petal details or stamen and anther studies - or perhaps the insects which are alighting on your plants. Macro and close-up photography opens up a whole new world of appreciation and it can be quite addictive!
Being able to zoom in sharply on small details can be a real challenge, especially if we’re new to close-up photography. Many zoom lenses have pretty good close-up capabilities - not on par with a macro lens, but often good enough to get you reasonably close to your subject. Start off by testing how close you can focus on an object at different points in your zoom range. If your camera has a high megapixel sensor then you can crop a little as well. That said, it’s unlikely that a non-macro lens alone will get you the kind of magnification you want, so you’ll need to look for another solution.
We all know that a dedicated macro lens is a great option, albeit a generally expensive one. Macro lenses vary in focal length and magnification so it’s important you choose the right option for the kind of photography you enjoy. I own the Olympus 60mm f2.8 macro lens (a micro 4/3 lens) which is one of the best macro lenses on the market. I use it on my Panasonic GX8 camera. In 35mm terms this gives me a focal length of 120mm, and therefore a reasonably long working distance should I need it, and plenty of magnification. But you don’t always need to make that kind of investment when you’re starting out. There are some inexpensive and fun options you can try first.
INEXPENSIVE WAYS TO ENJOY CLOSE-UP PHOTOGRAPHY
Let’s start with ‘reversing rings’, which do exactly what they say - your lens will be mounted on your camera in reverse. Naturally this will mean that the camera can no longer communicate with the lens, therefore a lens with a manual aperture ring will be useful. Otherwise, you need to set your aperture before you reverse your lens. Using reversing rings also means that you won’t be able to focus your lens and will rely on small movements of your body to bring your subject into view. Prime lenses which fall into the wide-angle category are favoured for this kind of photography - the wider the lens, the greater the magnification (and the shallower your depth of field) when reversed. We also need to remember that the greater the magnification, the more obvious camera movement will be.
If reversing the lens doesn’t get us close enough to our subjects, we can add “extension tubes”. This involves attaching the reversed lens to the extension tube and then mounting the extension tube end to the camera. Extension tubes can increase the magnification by another x2. The downside of this method is the loss of light, usually around two stops. This is normally mitigated by using flash.
Then there are ‘close-up filters’. (often referred to as ‘diopters’). These are glass elements which are screwed onto the front of your lens. The strength of the filter determines the degree of magnification (they can even be stacked). This article is going to concentrate on the use of these small handy filters because they represent the simplest way to begin a close-up photography journey.
USING CLOSE UP FILTERS FOR FLOWER PHOTOGRAPHY
What are the benefits of close-up filters?
• Convenience and portability: they take up barely any space in your camera bag and can be whipped out in an instant and attached to the front of whichever lens you’re currently using
• Price: a high quality macro lens is expensive. If close-up photography is an occasional pursuit it can be hard to justify the outlay. A good quality close-up filter on the other hand is quite affordable
• A close-up filter can be used on a variety of your lenses. Simply buy the filter size which best meets your current lens requirements and use stepping rings as needed on lenses with a different filter thread size
• Depending on which magnification level you choose, and which lens you mount your close-up filter onto, you can achieve remarkably close-up photographs of tiny objects
What the disadvantages of close-up filters?
• Optical quality will rarely match that of a dedicated macro lens (however the Raynox macro adapter is optically superb). When buying a close-up filter it’s really important to buy the best quality ‘achromatic’ filter you can afford
• A close-up filter acts a bit like a magnifying glass. It won’t turn your lens into a telephoto lens. This means that once you attach it, it’s purely for close-up photography. A proper macro lens on the other hand is an all-round optic and will double as a good choice for portraiture and any other application which suits that particular focal length
• Assuming you’ve bought a good quality close-up filter, remember it will only be as good as the lens you mount it onto. For best results make sure that your starting point is a lens with very good optical quality
WHICH CLOSE UP FILTER SHOULD I BUY?
There are plenty of close-up filters on the market. I own the Raynox 150, the Raynox 250, the Marumi achromat +3, and the Hoya +4. There are others out there and the NiSi products are well regarded. You can even buy a macro attachment for some mobile phones. I’d recommend buying the best close-up filter you can afford.
The Raynox filters are regarded as an excellent choice (albeit at a higher price point than most close-up attachments). Not only are these optically very good indeed, they have the added convenience of simply clipping onto the front of your lens. I have both the Raynox variants, the 150 and the 250. The latter demands a little more skill and attention given its higher magnification, and in general I would recommend the 150 to start with. The 150 is the one I use the most, because my close-up photography tends to be hand held whilst out and about. Higher magnification filters are best suited to use on a tripod. If buying a traditional screw on filter, a +4 is a good one to start with.
The Raynox 150 has a close working distance of about 8 inches, the R250 is around 4 inches. It’s possible to work out the amount of magnification you’ll get from these filters on a given lens by using a simple formula: Raynox Magnification = Focal Length of Primary Lens / Focal Length of the Raynox. The focal length of the R150 is 208mm and the focal length of the R250 is 125mm.
The longer the focal length of your lens, the more magnification you’ll get from your close-up filter. If you tend to use shorter focal length lenses you may find you prefer a more powerful diopter.
Close-up Filters ….
There are plenty of close-up filters to choose from. They vary in strength and quality, so think carefully about your needs before you purchase. Shown on the left is a traditional screw on diopter made by Hoya, and the Raynox 150
GETTING SHARP IMAGES USING A CLOSE-UP FILTER
Start by practising how your working distance and depth of field changes as you zoom your lens in and out with your close-up filter attached. Using a zoom lens at the telephoto setting will give you the widest working distance, the largest magnification, and the least vignetting (darkening around the edges and corners of the frame). It will also give you the shallowest depth of field, which makes accurate focus trickier to achieve. Practice is key. If you already own a macro lens, you can attach your close-up filter to that as well.
It’s fine to use autofocus (if your camera to subject distance allows for it) but manual focus can give more accurate results. Set your camera to manual focus and gently adjust your position back and forth until your subject comes into sharp focus. I find that using the ‘focus peaking’ functionality on my mirrorless cameras makes a huge difference and I would recommend you try that. It should be said though, that some cameras have more accurate peaking than others. All of this assumes you have a fast enough shutter speed to avoid camera shake when hand-holding. A tripod is a huge advantage at times, but can often be completely impractical when we’re out and about.
Once you delve into close-up photography you’ll immediately see that at ‘everyday’ apertures like f5.6 your depth of field (your plane of sharp focus) is very narrow at high magnifications. For that reason, we need to carefully consider where we want our point of focus to be. There are a number of factors which influence DOF. The longer your focal length, the shallower your depth of field. Likewise the closer you are to your subject, since both of these affect magnification. The size of your camera sensor can also have a large influence on DOF - the larger the sensor the shallower the depth of field will be at any given aperture value when compared to a smaller sensor. Therefore a smaller sensor camera can have real advantages for close-up photography since they will offer an inherently longer/wider plane of focus.
Aperture values with a small number such as f2.8 will offer much shallower/narrower depth of field than a larger numerical aperture value such as f22. The higher the number, the smaller the aperture hole will be and consequently more of your subject will be in focus. The downside of choosing a tighter aperture is that this reduces the amount of light reaching your camera’s sensor. To get the exposure we want we have the choice of slowing down the shutter speed (which may affect our ability to handhold our camera without introducing camera shake into the image) or increasing our ISO sensitivity (which will introduce more noise into the picture). Whilst you may feel the latter option is off-putting, a sharp image with a little noise is vastly preferable to a cleaner image which is blurred! Better still, use a tripod if your situation allows it. Another way to achieve sharp images (particularly at the tighter apertures) is to use flash - but I’ll talk about that in another article.
The Convenience of Diopters ….
Close-up filters (casually referred to as ‘diopters’) come in varying magnification levels. Here I’ve used my Raynox 150 clipped to my Fuji 15-45 kit lens in order to take a close photo of a daffodil bud.
Decide What you Want to Achieve
It’s important to consider your intent before choosing your settings. This will determine whether you’ll hand hold your camera for the photograph, or whether you’ll need to use a tripod (and perhaps the focus bracketing and stacking features I’ll talk about in a moment). Ask yourself what the purpose of the photograph will be:
Do you want a very shallow DOF image which is ethereal, softly blurred through much of the frame, with a ‘dreamy’ and creative look to it? A wide to normal aperture and hand holding (if the light is good)
Do you want to isolate a detail in an otherwise busy scene? A wide to normal aperture and hand holding (if the light is good, a tripod if the light is less than ideal)
Do you want to capture more detail in order to appreciate the shape of a bloom or insect, or to create a more scientific study? A tripod, a tighter aperture and a potentially focus stacking techniques
MAGNIFICATION WITH AND WITHOUT A CLOSE-UP FILTER
To set the scene, I’ve taken some photographs which will show the kind of magnification I can achieve both with and without a close-up filter. I’ve focused as close as I can get for each photograph. By way of comparison, I’ve also taken a photograph with a proper macro lens.
The Raynox 150 and 250 are mounted on my Fujifilm XT200 with the XC 15-45 zoom (the Olympus 60mm f2.8 macro lens is mounted on my Panasonic GX8).
For a “standard zoom” the close-up abilities of my little Fuji 15-45 kit lens is pretty good - about 13 cm at the 15 mm end. The Olympus 60 mm macro lens has a closest focusing distance of about 19 cm. With a close-up filter attached it’s possible to get closer to the subject.
For this test I used a grape hyacinth from my garden - the flower head is approximately 4 cm high so it’s not a particularly big subject. I focused on the central petal trumpet. I handheld all of these pictures since that’s going to be our most likely scenario out in the field. That did mean that I had to use a fairly high ISO setting (1600 in most of the images). I used an aperture of f5.6 which gave me shutter speeds between 1/50 and 1/60sec. The Fuji lens has image stabilisation and the Panasonic GX8 camera body does as well, so there were no issues with camera shake.
We can immediately see from the pictures how the magnification changes (the pictures haven’t been cropped in any way). The photographs are all sharp - despite the fact I was handholding these in less than desirable light. The Olympus 60 mm macro lens is one of the sharpest optics I own, but the Raynox 150 and 250 hold up very well. Using the Fuji kit lens I set the zoom to about 40mm.
Fuji XT200 with 15-45 Lens
Fuji 15-45 Lens with Raynox 150
Fuji 15-45 Lens with Raynox 250
Pana GX8 with Olympus 60mm Macro Lens
If you have a Raynox, it will clip onto any lens with a 52-67mm filter size, using the supplied clip-on attachment. You won’t need the clip-on attachment if your lens has a 43 mm filter thread. For any other filter sizes you’ll need step up or step down rings. If you have a compact camera with a built in lens, Raynox sell a variety of attachment fittings.
The principles relating to the use of close-up filters are the same, whether you use a Raynox or any other magnifier.
MANAGING SHALLOW DOF IN CLOSE-UP PHOTOGRAPHY
The most obvious way to mitigate the effects of ultra shallow depth of field in close-up photography is to stop down the aperture. A higher f-number means a smaller aperture, and hence deeper depth of field. The result of a smaller aperture is less light entering the camera, and we have to balance that with a slower shutter speed (and/or much higher ISO values). For hand holding an aperture up to f8 can be a safe bet if the light is good, but if tighter apertures are needed we’ll have to use a tripod.
Some modern cameras have interesting features valued by macro photographers. Panasonic and Olympus cameras are notable in this regard. Of interest to this discussion is ‘focus bracketing’ and ‘focus stacking’. Depending on your model, you might have one of those features, or both. In essence, you can set your camera to take a series of images with variable focus points and then either stack these in camera or externally using software. This is a fantastic way to get a predetermined amount of sharp focus in your image.
I have an older Panasonic camera, the GX8. It’s a great piece of kit but it doesn’t have either of the features I’ve just mentioned. It does however have a feature called ‘Post Focus’. The camera takes a 4K video clip which enables us to select different frames and to choose where we want the focus point to be in each of those frames. The downside is that the clip is recorded as a JPEG at half resolution. Our series of selected pre-focused frames can then be focus stacked in software. One of the best features of the 4K Post Focus setting is that it’s good for handheld work (we won’t need to tighten our aperture either). It works well for flowers that are waving around in the wind, or for insects that are darting about erratically.
Lastly, light is everything in photography. Good use of light helps us to reveal the shape, form, and texture of our subjects. I’ll be talking about light in a later article.
I hope this has given you some usable and easy to implement ideas for close-up photography. Close-up work is great fun and it can be very addictive!
For a more general overview please see: plant and flower photography tips