As many of you will know I enjoy landscape photography, visiting exotic locations and wide-open spaces. When lockdown was announced and being in the age group that was high on the virus’s choice list, I decided to turn my photographic skills to the challenge of macro photography focussing on bugs and flowers in the garden.
I ordered a 90mm f2.8 macro lens for my Sony mirrorless camera and found they were in short supply presumably because a lot of other photographers were thinking along the same lines as me. After a 3 week wait it arrived and I quickly attached to my Sony A7Riv and rushed out to take some pictures.
After several hundred pictures I found out that those little creatures constantly moved or if they had wings flew away, giving me beautiful blurred or out of focus shots. Worse still when they were in focus the depth of field was so narrow and always seemed to be focussed in the wrong place.
The solution appeared to be that I buy a ring flash for the camera which would freeze the shot and at least give me some sharp pictures. I then found that I needed to diffuse the flash as it was way too bright and gave specular highlights everywhere. I experimented with all sorts of materials and was moderately successful, but it was hard work and the success rate was low and I was still stuck with very shallow depth of field.
I had used focus stacking in the past to give me sharp front to back pictures for my landscape work but this was usually achieved with three shots (foreground, middle distance and background or horizon) and the landscape didn’t move!
After some further research I was advised by a friend to buy a stacking rail and I purchased one from
UltraMacro www.ultramacro.co.uk. The chap who sold it to me was so helpful and full of good practical advice and the equipment arrived within a day or so. There was good documentation and it was easy to set up. It is powered by either mains electricity or a rechargeable battery pack for field work. I had made my mind up that I would use it to photograph still insects (a metaphor for dead ones!) or flowers/plants.
A focus stacking rail works by setting the camera to manual and manually focussing on the front of the object you wish to photograph. The focussing rail then mechanically moves the camera forward by predetermined amounts until the focussing point reaches the back of the object. This is in contrast to in-camera focus stacking where the camera is stationary, and the lens is incrementally focussed throughout the process.
I mounted the stacking rail on a sturdy piece of wood and fitted a tripod head to the stacking unit using the supplied ArcaSwiss fitting. My camera fitted on the tripod head and the camera shutter was controlled via a cable from the stacking rail by the software supplied as an app for your phone.
My first subject was a large house spider which was dead, and I carefully mounted it in a lifelike pose! My results using the stacking rail and an off-camera ring flash
1.
This was shot at f8 using 35 images with the stacking rail moving the camera 0.85 mmm each time between shots. I typically allowed a 3 second delay before the next image after the camera had moved forward to let any vibrations from the motor to dissipate.
I decided at this point (and being pressured by my wife not to harm any insects) to switch my attention to small flowers. I was also keen not to use flash and rely on natural light. I used a piece of black card as my backdrop and faced the light to give some rim lighting to my subjects (see above picture for setup)
Using a mirrorless camera means that what you see is what you get—you are in live view all the time. I set the camera to manual and my aperture to f8 and then dialled in the shutter speed to suit the look and exposure I wanted. I did this all in my office on a suitable desktop and adjusted the light entering the office by lowering the blinds on the window. This also helped to keep the ambient lighting level throughout the focus stacking sequence which would typically run between 4 and 6 minutes taking 30-40 frames. Shutter length was 0.5-1.5 secs per frame and there was about 6 seconds for the rail to move forward and settle before the next shot. All these timings were set up in the software prior to the sequence with the software doing the calculations for you.
I typically shot in JPEG mode (the Sony A7 produces a 40mb file and having 35 of these is a big stack to deal with!) and processed them in Photoshop. Photoshop did a reasonable job but there was a lot of ghosting and odd pieces where fine details overlapped. As the stack was a series of layers in PS you could go back and try and correct, but this was not easy. I then tried a dedicated piece of stacking software called
ZERENE STACKER www.zerenesystems.co and this gave me almost flawless results first time and so I purchased it—you get a 30 day trial so you can try it out first. I also found that it was better to slightly underexpose your images as you capture them. Any specular or bright highlights gave some ghosting even in Zerene and you can correct this exposure in the final stacked image. Zerene does not work with Raw files so my choice of Jpeg was fortuitous. It can work with Tif files but I found Jpegs just fine.
All the pictures shown were shot using natural light and all the flowers/grasses were no bigger than 1-3 cm with individual flowers typically being 5-8mm.
I was truly amazed at the detail I captured, and the natural lighting added a beautifully even light to the subject matter.
If you would like to have a go and want some help/advice I’m happy to do my best. I hope you enjoy my pictures as much as I did making them. The true beauty of these pictures are really apparent when viewed on a large screen.
