Using small aperture in single frame macro

The opposite of the previous post, some subjects are more suited for a highly stopped lens, the "wood" tortoise beetle have a face and body with complex geometric structures and need a lot of depth of field to cover the more important part. Also the kind of detail present in the in focus parts is not much diffraction sensitive, there is not need of highly detailed compound eyes as the ones of him aren't so important in composition as fly eyes for example, and the surface structures have a fair amount of detail even at this aperture setting.

Photo is with Canon MP-E 65mm 2.8 macro photo @ about 3.5 magnification, Canon 7D and yongnuo YN560 manual flash. Aperture of f/11, but at this magnification the effective aperture is near f/50

The blue sky is the result of long exposure time of 1/13s and is possible to observe this movement in the right antenna.

If you compare this image with the one from the previous post the dramatic difference in depth of field is not so noticeable, possibly the choice of aperture is much more subject dependent.

Using large aperture in single frame macro

Shallow depth of field is considered a mayor problem taking macro images in magnification higher than 1:1, as most of the subject is out of focus. Several techniques developed to increase the depth of field, I'm not defending one against another because I use most of them in a daily basis. The history of this post is how to use successfully a wide aperture (relatively in extreme macro terms) in one single image still preserving the interestingness.

Portrait of a male of Lynx spider by Gustavo Mazzarollo, Canon MP-E 65mm macro photo lens @ 3x magnification and f/6.3, the effective aperture is about f/22

 

The main shortcoming is finding a suitable subject that has enough of the body geometry in a flat plane in order to allow the shallow DOF to cover enough area for detail perception. The lynx spider is one of these suitable subjects. These photos were taken with Canon MP-E 65mm macro photo lens @ 3x magnification and f/6.3, the effective aperture is about f/22 , doesn't look like a lot of aperture, but successful extreme macro shooters that made most of the images single framed usually goo to effective apertures of f/50 or more (flash required). There were advantages of taking the shoot at a wider aperture, it allows more natural light to participate in exposure creating a natural light background, it allows a reduced flash time for the needed exposure and reduce the diffraction softening creating more interesting detail in the in focus area. The subject is still exposed by flash, if the flash fails will result in a shadow image were the spider is, the flash is important to preserve detail too, it stops the motion and prevent macro motion blur, flash power is defined as duration of the pulse, the shorter the pulse the more chance of getting a sharp macro and the wider the aperture the shorter the pulse.

Lynx spider side view photo by Gustavo Mazzarollo, Canon MP-E 65mm macro photo lens @ 3x magnification and f/6.3, the effective aperture is about f/22

In artistical terms there is not problem in placing a small portion of the subject in the point of focus, some people buy expensive fast lenses only to achieve shallow depth of field in human portraits, and conclude that this isn't enough, end by buying a full frame camera, to make the deph of field even shallower, as as far as you have enough detail to be appreciatted and the shape and color of subject present, some brain mechanisms reconstruct the whole image. I usually do this by doing test shoots and seeing the widest aperture possible that preserve the detail, sometimes I do focus stack of two or a few more images for the effect, but this isn't always possible with a live moving subject. The frontal portrait below was done with several testing aperture in several shoots until figure out the best aperture:

Pentax papilio binocular review

One of the most interesting tools for outdoor photography are the binoculars, and for the ones exploring the small world, pentax designed the specialist instrument that we need to look closely, the pentax papilio binoculars.


One of the most distinctive features of the papilio are the converging objectives, for good image merging at closer focus, the video demonstrate how this works:

At close focusing distance and seeing  with just one eye it cover 50mm of ruler, with the two eyes it cover about 7cm field of view, at closer focus. Infinity focused the 6.5x magnification give about the same image of a 200mm tele in a APS-C sensor camera.

Have seen citations in internet that when at closest focus the magnification in fact is more than 6.5x, but never found the complete information. As a test, I measured the exit pupil as 2.85mm when at closest focus and about 3.30mm when focused at the end of range. At middle of focusing found 3.25mm exit pupil so I believe it decrease in size more as the focus start to became close. (The advertised in the papilio booklet is 3.2 which is in line with the 21/6.5 = 3.23) By a simple rule 21/2.85 = 7.36 (magnification at the close range). This calculations are subject to errors, one is that I measured the exit pupil with a micrometer seen by eye, another is the possibility of aperture change when the binocular focuses close that could result in a smaller exit pupil.

As you get closer the subject you will run depth of field problems, I have found at the closer focusing distance when the binocular is at a 45º viewing angle from the subject (one of the most used angles for practical purposes). The usable depth of field is about 8mm, but the real depth of field parallel at the subject should be about 2mm, this is under low light conditions. For simulation I have found the depth of field to be the same of the canon 100mm macro lens when at 1:2.2 and f/3.5 (this is by ruler observation not by magnification calculations). Another interesting point is that at full sunlight looks there is a increase in the perceived depth of field, from to the point of f/7.1 or f/8 in canon 100mm macro.

Stereogram of a flower with Canon 100mm macro @ about 1:2,2 magnification, this photo is the best match I could do to simulate the pentax papilio 6.5x binocular at the closest focusing range, crossing eyes result in a merged image with a sense of 3D compared to the binocular image.

It's possible this increase in depth of field is more related to observer eye physiology than for the optics as the binocular always work wide open. One possibility is that in full sunlight the pupil is so small that act as a diaphragm increasing the depth of field. Another possibility is the fact that the human eye have worse resolution at low light conditions and possibly there is more selective attention to the area in focus (low ability to resolve detail is compensated by selective observing of the more detailed areas, a theory to be confirmed) resulting in a false perception of short DOF, while in full sunlight conditions there is more capacity to observe detail.

Uses and observation at different distances:

The papilio truly shine for observation of bushes in low light scenarios, the relatively wide field vision and bright of the 6.5x version is perfect for this scan and the optics of this binocular works better at close distances, at this observing arena is possible to see the fine movements of a jumping spider at each jump, the detail of mating beetles and interesting feeding activities of the insects, it make me slow down and observe interesting behaviour to be registered in shoots in future. The resolution is enough to resolve a medium size fly o compound eyes, when the fly is steady, the eye pattern is clearly seen, or the compound eyes of a medium size beetle, is possible to observe some detail in a jumper spider with the movement of legs in 3D at each jump a very interesting observation.

The middle of focusing range is very good for inspecting bushes and scanning trees at distance of 1,5 to 4 meters (this is already covered by some roof prism binoculars but the papilio allow to to get close when something really interesting pop). For focusing objects at infinite or distant the papilio give a good image but not stellar as the long range binoculars, at night observing stars the papilio give a gain of magnitude of (I believe about one half magnitude), some star clusters not visible at naked eye are possible to spot with the papilio but the resolution is not on par with astronomy binoculars, of course I wouldn't expect too much for the 21mm aperture. The papilio truly shine at close observation and the images taken at long distance should be seen as a bonus of the binocular.

One unexpected but appreciated excellence of this binocular is for flower photography, with his images is possible to observe the best angles to capture flowers and a fast survey of the available backgrounds for faster setup of the camera, is much faster than with camera alone and the binocular view prevents a lot of the tiredness involved in scene study.

Build: It's plastic :) and you should take care of it to avoid high temperatures and other abuses, have read consumer reviews of people who desire a metal build and better resolved optics binocular as the papilios are the only one that allow this close observation (something like the most expensive well build roof prism birding binoculars). I do not share these opinions and I personally prefer the binocular the way it is, the resolution is good enough to observe detail and considering the most subjects will be moving (even the flowers will have movement by wind) more resolved optics would be a expensive overkill and for observing dead insects or flowers inside home there is the better resolved stereomicroscope, for this binocular my opinion is that the plastic is preferable than metal, as my macro gear is already too heavy.

Use and constancy Have the binocular for tree months at the time off this review, used it a lot in the first week test period, and left behind just after, as the weeks passed I'm using it more and more as I discover more usefulness of his features.

Leafcutter ants

        These are photos taken under pressure, was the end afternoon and a big storm was on the way, these usually run the production when they feel the storm approaching, and at my side there was little time to take the pictures too. They work in a line formation and from the shoots I was able to produce two keepers:

Leafcutter ants in group, in the leaf is possible to observe a soldier raider. Photo by Gustavo Mazzarollo available for license on Alamy

        And a similar, same ants with small time difference, isolated from the other in line ants:

Leafcutter ants soldier and raider isolated. Photo by Gustavo Mazzarollo available for license on Alamy

        Notice the raider ant is very important as it protect the workers against flies to land in leaf and oviposing in the worker's head.

        I wasn't sure what of the two will work better, as image, and online feedback is very important. Here opened a very interesting and "dual mode" feedback, these images received unexpectedly few comments in the macro photography forums, but in a very interesting way they were successful on Flickr being the first two in the year to reach explore (the 500 selected photos uploaded in a day). In a positive manner, each media returned feedback of people who prefer the first, for the teamwork spirit and the ones who prefer the second for better isolated subject. This stalemate of images is good but I'm not sure if they are truly similars or takes of the same scene that resulted in very different mod images, and not sure if I could get a response some day.


        From the photography perspective, is worthy to note the ground looks well in the ants perspective (if I were from the size of a ant and with a mini camera would need to crouch to achieve this perspective), and if they were really in the ground the frontal element of the lens would need to be below the ground to achieve this perspective. But these photos were made in the corner of my water tower:

 

         The dirt worked to create a illusion of soil, and the angle allowed for include some of it as background and even show the ants at the insect level.

The honeydew hungry ants

These ants feed on the nymph's honeydew drops, the nymphs get it from the vegetation and feed the ants in exchange of protection, I believe the honeydew even increase the ants agressiveness as they become more active and prone to attack when near a scene like this.

My ambition was to capture a image with the ants at the moment of feed and this group of nymphs produced small drops in relatively frequent quantities, the site for the capture was selected in base of this.

Side view of a honeydew hungry ant at the moment the nymph released the honeydew. This photo is with Canon MP-E 65mm macro at almost 2x magnification on Canon 7D and is a stack of two photos. The main photo is with f/7.1, effective aperture of f/21 with a estimated DOF of about 0.4mm. This was the best photo at iso 100 Photo by Gustavo Mazzarollo available for license on Alamy

Macro photography favour stop motion usually with flash photography, there's a balance where the challenge is to produce the best possible frozen moment, at the magnification that give at the same time detail and surroundings information (usually increasing the magnification results in huge light losses) with the less possible flash time. Macro photography also favour low iso.

Unfortunately in this first photos where affected by motion blur to some extent (longer flash times to work with the small apertures needed to capture two subjects interacting in one frame photo).

Usually the macro technique for insects involve reduce movement by the photographer side and by the subject side, reducing the subject side usually is done by the use of sugar, some substances that work as anaesthetics, or taking the shoots at cold hours where the insects are motionless. Unfortunately the objective of wasn't to take the pictures of ants, or of the nymphs, but photos of the interaction of them so reducing subject motion is not desired in this circumstance.

The best I could imagine for this is reducing the flash duration time while at the same time using narrower apertures to increase depth of field, this time raised the iso to 500 (proved to not harm this much the pictures, noise still under control)  and was possible to reduce the flash time. This increased the rate of keepers and proved to be a good solution for a situation where the subjects where relatively unpredictable.

For reducing the motion at my side I used a monopod (not used in the first photos) to reduce the fatigue waiting for a moment in a relatively uncontrolled scene This scenes were in a bush at 1.20m from ground so the monopod helped with the need to keep the gear lifted for longer time.

Ant waiting for the honeydew from the nymphs, this one is more magnified, with Canon MP-E 65mm lens at almost 2.6x magnification. Same nominal aperture of f/7.1 but more extended lens result in a effective aperture of f/26, as the magnification increased the depth of field decreases I estimated to about 0.3mm. Photo by Gustavo Mazzarollo available for license on Alamy

Looks the difference of exposure and aperture to not be that big among these two pictures, but the second one have better histogram distribution and a much smaller flash time than the first resulting in a more detailed capture. Personally I prefer the moment of the first photo, but the second I consider better technically, even at 200% magnification the noise differences weren't noticeable (the same amount of noise reduction was used in the two pictures). As a disclaimer, raising iso's at macro photography is a techinique of exception, most of the time the subjects weren't this active to require raising iso's and the flash itself do a good job stopping the motion.