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Macro lenses offer a fascinating window into the world of the tiny and less observed. With their powerful ability to focus sharply on subjects at extremely close distances, macro lenses reveal intricate details and textures that are often overlooked by the naked eye.
For filmmakers, macro lenses provide opportunities to add visual interest and depth to scenes by capturing extreme close-ups that immerse viewers in the finer details of a story. Whether it’s showcasing the subtle expressions on a character’s face or emphasizing the minute elements of a setting, macro lenses can enhance storytelling and evoke emotions in powerful ways. These lenses can also create evocative images in the world of natural history and commercial product filming such as jewellery. Stop motion animation should also not be overlooked, having a highly useable macro lens set in that space is invaluable.
Cooke Optics’ range of three dedicated 1:1 Full Frame Macro lenses afford the discerning cinematographer these creative opportunities, supported by ground-breaking construction and full frame imager coverage. The construction of Macro lenses is as impressive as the images they can create; here we’ll explain some aspects of optical design to present an insight into the macro world.
Let’s consider a telescope – it’s a tool used to enlarge the apparent size of a distant object in order for us to observe details much better. With your naked eye the moon for example is very small in your full field of vision – it subtends a narrow angle on your eye. A telescope then increases the size of the angle the moon subtends – it’s magnified.
Thinking about cinema lenses in terms of magnification then can be bemusing because in general they’re taking something large within our field of vision and imaging it onto a smaller negative or digital sensor area. As such they’re reducing the size of real-world objects instead of increasing them or presenting them as life sized – this is called transverse magnification. If a lens reproduces an image of a real-world object that is 10% the size of the original on the imager then that is a fractional magnification of 1/10 or a ratio of 1:10. The magnification of a lens is a property of the focal length and the distance to the subject, rather than the size of your imager.
A true macro lens allows for a 1:1 magnification ratio meaning if we had a 18mm high image sensor (super35), an object that was 18mm tall and placed at the lens’ minimum focus distance would fill the whole height of the imager.
When a lens is set to infinity focus it is the closest to the imager that it can be. As the focusing group moves further away the focusing distance becomes closer. There comes a point in standard lenses where you cannot move the lens any more without a failure of the mechanics, an impractical extension of the lens barrel length, or an unacceptable induction of aberrations. This point then becomes the lens’ minimum focus distance – commonly referred to as ‘close focus’. Macro lenses go beyond this point so are therefore often employed for extreme closeups and have mechanics specifically tailored for the purpose.
Whilst all true macros reach this 1:1 magnification sweet spot it’s regularly beneficial to use a longer focal length for macro work as it allows more working space around the object for lighting etc – having a range of macros to utilise is invaluable, especially if incorporating them with other shots in a sequence and attempting to avoid too much of a jump in style. Cooke’s three lens range of 60mm, 90mm and 150mm offers great flexibility in this regard.
As the focusing components of a lens move further away from the imager the image circle is spread out resulting in a loss of light. In ordinary circumstances this range of change is small enough that it’s not a factor that needs considering. However, in the macro world when reaching extremely close focusing distances this change is more significant. In general, the rule of thumb is that a 1:1 macro will lose two stops of light when set to minimum focus. However, Cooke’s lenses surpass this and other competitor’s offerings, with stop loss ranging from 1.4 to 1.8 depending on the focal length.
It’s well known that the closer your lens focusing distance is set to the less depth of field you’ll see in an image and this is also true in macro. However, in macro, depth of field is independent of focal length; for example, a 60mm and 15x0mm both set at 1:1 magnification will have the same depth of field. In addition, the depth of field is equally split in front of and behind the point of focus – unlike in everyday shooting when the depth is more weighted to being behind the point of focus.
The close focus of a lens can be improved through the use of dioptres but this shifts the range of focus closer and means that infinity and further distances can no longer be reached. The use of dedicated macro lenses allows for greater narrative expression including dramatic focus pulls from far to macro focus.
It is challenging to maintain the performance of a lens at close focus distances, as such speciality macro lenses have come about. The trade-offs can be having more compressed focus scales in the “normal” working distances and additionally they often expand in length considerably as they are focused closer.
Cooke usurps these expectations with fully internal focus mechanisms and matched front diameters of 87mm meaning there’s no issues around using clip on matteboxes. Matched iris and focus gear positions also make lens changes easier and advanced cam-followers allow for incredibly precise focusing from infinity all the way to 1:1 – these lenses are equally at home for principal photography as they are for table top product close-up shots.
Unique to the macro world they feature Cooke i/Technology allowing for constant readout of lens metadata and with image circles of 46.3mm the lenses comfortably cover larger formats. Being colour matched to modern Cooke Primes at T2.5 means they can be intercut without issue. Lens breathing is more exaggerated in the macro world but in these lenses, it’s controlled incredibly well and is never distracting.
Find out more on our Macro Lens Page and expand your canvas!
