I have a plan to buy and use a Parker MX80L Linear Servo Stage and use it for macro photography at high magnifications like 50X. It also has a ViX-250IH Drive with it (I have no idea about it.).
Has anyone tried to use it for macro?
It has 0.01um resolution and it is a very stable rail.
I have worries about how to control it.
Is Wemacro or Stackshot controller can be used to control this system or need special software and pc to control it?
If so how to trigger the shutter, do I need an extra pcb to control the shutter?
I am waiting for advices and opinions from all members that have experience on this toppic.
Looks like you won't get along without programming... Servos are different beasts compared to steppers. Good thing is, that documentation and software is available, no need to reverse engineer.
Another link to get a glimpse whether you want to take the challenge or not:
Quote from above:
" The difference may seem insignificant, but this tells us something fairly critical: Doing anything with the VIX requires writing programs of reasonable complexity. In fact there is no configuration option for step/dir input - we are going to have to program that ourselves! The majority of the 250 page manual describes the "EASI" programming language, complete with subroutines, loops, conditional statements, and much more. The drive itself has a selection of input and output pins, and the whole experience feels a lot like programming the 1990s equivalent of an Arduino.
This unexpected in a servo drive and would probably scare most non-programmers away. It does, however, provide some extremely powerful options if you are willing to take advantage of them."
And here's the software (requires Win XP or older )
It's really looking very stable and usefull for extreme macro, especially upper 20X magnification!
I also need something like this, because wemacro doesn't enough anymore. If you find a way to cotrol and programing this stage with inspritional answers, then i can get one of them.
I also have three servo rails lying around here, but no manual. I have found out quite a bit about the protocol (there's an AT Mega controller built in), but i am still far from being able to use those.
This looks like a lot of work and requires specialized skills in programming and electrical engineering as well as control theory. If you have those skills or willing colleagues this might be an interesting project to attempt to tackle, however if your intent is to get a really good and stable focus stacking rail system capable of 20X or better other options might be worth considering.
Stackshot, WeMacro and MJKZZ have very good focus rails systems and can work to 20X with very careful setup and rail loading (reduce backlash and wobble). Stackshot is the most versatile focus stacking system of the 3 and the controller allows various stacking parameters to be entered, and works directly with stacking software Zerene.
The modified surplus THK KR20 linear rail with 1mm thread pitch works very well as a rail and can be directly controlled from the Stackshot or WeMacro controllers. This is a highly precision industrial surplus rail you can find on eBay usually for under $200. Peter at MJKZZ has a modification kit that includes a 400 step NEMA 17 motor and the necessary brackets and such to convert the THK KR20 for focus stacking use. The controllers mentioned can directly control the modded THK with the needed precision for stacking to 20X and beyond, all that's required is a custom cable for the controller to the stepper motor.
I have all these rail systems, Stackshot, WeMacro, MJKZZ and THK KR20 and know they work and how well they work together. The best overall combination I have is the Stackshot Controller with the THK KR20 & MJKZZ mod kit, however the WeMacro controller works very well also.
Don't discount your base setup either, at 10~20X everything will affect you. Vibration is the biggest challenge; camera mirror & shutter, sounds, walking, doors, cars, airplanes flying overhead, even air movement can and will affect your results. The effective pixel size as "seen" from the subject is camera pixel/magnification, so at 20X your camera ~4 micron pixel "looks" like a 0.2 micron pixel! If you just pick up a 10cm long piece of aluminum at room temp (~22C) and hold it (~36C), the length can change by ~3 microns!!
Best and good luck,
Last edited by mawyatt on Fri Mar 23, 2018 7:02 am, edited 1 time in total.
Research is like a treasure hunt, you don't know where to look or what you'll find!
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Hello Omar,
I would suggest that you take the best linear stage you can find and assemble only the controller.
You can disassemble an old microscope too. In my big version of the macro-slat I have used one from Mitutoyo.
BTW, such controller (Arduino based) can be used with any step motor (e.g. NEMA 17).
This solution is really reliable, flexible and cheap :-)
BR, ADi
With the limits of diffraction and wavelength of green (~0.55 microns) I don't think I'll be getting into anything beyond what the THK KR20 can achieve. With a 400 step motor and 1mm thread pitch, each step is 2.5 microns. Micro stepping can get to 4 (0.625 microns) or 8X (0.3125 micron).
Once you get to these levels I think it's highly uncertain you can achieve any repeatability, nor even assure yourself that you are actually moving the step size you've commanded. How would you measure and know sub-micron performance without very expensive equipment unlikely to be in the hands of us amateurs? Even if we could move at these levels, do we need to and can we take advantage of this for focus stacking & imaging??
mawyatt wrote:How would you measure and know sub-micron performance without very expensive equipment unlikely to be in the hands of us amateurs?
The measuring part is actually not difficult. You just watch from the side with high magnification optics and use the image alignment functions of Zerene Stacker to track movement of a finely detailed target. See the thread "Tiny focus steps: how to make them, how to measure them" for movements & measurements summarized as "This is a sequence of 132 moves, the largest of which measures a bit under 0.14 microns (average 0.0625 microns)."
But that thread also illustrates another fact: it is simple to get very small focus steps by using a microscope focus block and motor control of the fine focus knob. See also the recent post by nanometer for an effective setup that doesn't even involve any machining.
I applaud lonepal's enthusiasm for pushing the envelope by mastering the Parker servo. But to make sense of that enthusiasm, I have to consider the effort as an educational and entertaining exercise in its own right. If the goal were only to get small and stable focus steps, there are much simpler approaches.
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