Sony a7s with 50mm f1.7 Rokkor, Minolta Bellows and the Neewer XY Slider
Many nature photographers dabble in close-up or macro work at some point, and in a discussion with harrietsfriend
, the availability of these pretty cheap (around U$20) sliders came up. My daughter got me one for Christmas, and Boxing Day was spent playing.
For stills, the device is spot on. You can move left-right or back-forward in sub-millimetre increments. When shooting at 2x magnification onto the sensor, your entire depth of field may be 2mm, or if you stop down heavily, 6mm. That's about where the image to the right is. Also, setting up precise framing for composition and getting the focus right with just a tripod is beyond my levels of patience. This device makes it quick, easy and accurate.
So, flushed with the technical success of the stills, I tried this whilst in record mode.
(if you are struggling to play this on dA, it also available on YouTube
The technicalities here are a bit different. The magnification applies to everything. Including the shake & jitters. I swopped to a more robust tripod, oiled the tracking mechanism, and worked as smoothly as I could but still there was a lot of shake. The slider uses a friction damping mechanism, and hand-turning the adjustments is very hard to control perfectly over time. Next time, I will try fixing a long lever to the knobs, and turning that - I think it may help.
The footage above has all been stabilised during editing in DaVinci Resolve. The stabilising tool there is pretty good, but the first rule of post-production processing is 'shoot it right', and it holds here. I am keen to shoot at higher frame rates - I can do 1080p at 50 frames per second, and 720p at 100fps. When you slow that down to 25 fps, it can really help the jitters.
Other observations from the process? The low light ability of the Sony a7s rocks. Shooting with the lens extend 13cm out from the body chews up light, and stopping down to f11 would normally require 2 second exposures. I didn't even have to think about that - at 10 000 and 12 800 ISO, the images are still really nice and clean. Certainly the reason people aren't clicking on the images is not related to the ISO. Also, that high ISO allows me to consider 100fps shooting, which demands a shutter speed of at least 1/100th of a second. Macro video just became a whole lot more accessible.
For the record, the lens - 50mm f1.7 Rokkor - and the bellows all date back to the late 1970's. So there is a 40 year time gap between optics and body. And still working fine!
So thanks Eugene, for getting me going along this path!