eMotimo Spectrum St4 Review – Hands on With 4-Axis Robotic Motion Control

What does it mean to have 4 axis robotic motion control?

Starting with just an eMotimo Spectrum St4 you have two axis robotic motion control – rotation (pan) and up-down (tilt). Add a slider and you’re got another axis – forward and back (push/pull). Add a new eMotimo Focus Fz unit and you’ve got your fourth axis – focus or zoom. (Or skip the slider and add a second Fz unit and you’ve got focus and zoom!)

So what exactly can you do with robotic four axis motion control? Think complex time lapse sequences with multiple silky smooth movements. Think live action video with precise movement and focus, zoom or aperture control.

If you are a timelapse photographer or film maker, the eMotimo Spectrum can enable you to make impossible shots – the possibilities are as endless as your imagination.

But what is it like to work with 4-axis motion control in the field? Continue reading for our hands on review of the eMotimo Spectrum St4.

Overview of the eMotimo Spectrum St4 and Updates

We previously spent some time working with a newly released eMotimo Spectrum St4 and published an article with our first impressions and an overview of its key features.

If you’re not familiar with the Spectrum – click the link to read our original review.

Since then, eMotimo has released a major firmware upgrade for the Spectrum, adding a few major new capabilities and they also released the Focus Fz for robotic control of focus (and/or) zoom/aperture.

The Spectrum St4 and Focus Fz are both very well built – with a milled aluminum body, excellent control software and a genuine Sony DualShock 4 gaming controller – this is professional level gear. In fact, eMotimo recently won a Red Dot Design Award in recognition of the excellent design of the Spectrum.

Here is a video overview of the capabilities of the Spectrum and Focus Fz and our experience using them in the field:

Key Features of the eMotimo Spectrum St4

Before we get to our review of using the eMotimo Spectrum St4 in the field, I want to point out a few of the Spectrum’s key features and what’s new:

1. Live Action Video & Timelapse – Lens Focus Aperture and Zoom

Since our initial review, eMotimo has released the Focus Fz unit that allows for robotic motion control of the focus, aperture and/or zoom on your lens for both live action video and timelapse.

With one Focus Fz unit, you can control either focus or aperture or zoom. With two Focus Fz units, you can control two of focus, aperture and zoom.

The Focus Fz uses standard 0.8 pitch gearing, but you will also need gearing on your lens. If you’re using standard photography lenses, you can use an add on gear. If you’re using cine lenses, they probably already have gears built in.

Here is an example of a two Focus Fz setup for control of both focus and zoom:

We should note that the Spectrum St4 is called the St4 for a reason – there are four axis available. So along with pan and tilt you can only choose a maximum of two out of the following four options: dolly push/pull, focus, aperture and zoom.

2. Live Action Video – Live Motion Tracking

The Spectrum has a number of presets for live motion tracking (the unit moves as you control it in real-time). There are modes for fast, normal, slow and quiet motion – and two new modes specifically designed for work on a dolly with the third axis.

One of the issues I had in our original review was the Spectrum stalling when on a dolly. This issue has been totally fixed – its bombproof now – even on a steep incline with a full size DSLR.

You also have the ability to set up to four return points – so that no matter where the Spectrum is, you can return it to a pre-defined alignment with the press of a single button (very useful for interviews or any time you need to be able to repeat a shot from a specific starting point).

2. Live Action Video – Programmed Shots

If you want to film precise motion, you can program all four axis of the Spectrum to perform a specific movement. One huge improvement eMotimo has made since our last review is the ability to program up to five keyframes.

Think about that for a moment. Instead of setting point A and point B and letting the Spectrum proceed linearly between the two – now you can assign three more points in-between. This opens up a ton of creative freedom and allows for some very complex shots that would otherwise be impossible.

For example, with a two-point move you could set the Spectrum to pan from Point A on the right to Point B on the left. With a three point move, the Spectrum could Start at Point A on the right, pan to Point B on the left and then rotate the opposite direction back to point A.

The best part is that you can program all four axis, and the movements are repeatable.

3. Timelapse – Programmed Shots

In my opinion the ability to set up to five keyframe timelapse sequences is groundbreaking.

We’ve gotten used to seeing motion in timelapse sequences, but the motion in each individual clip seems to flow in one direction – from A to B. That is a two point move. With a (up to) five point move you have so much more creative freedom to capture much more complex timelapse movements.

Add to that the ability to pull focus or zoom (or pull focus and zoom with two Focus Fz units) during timelapse capture and you’ve now got timelapse possibilities that (as far as I am aware) are only possible with the Spectrum.

4. Gigapan Photography

Since our initial review, eMotimo has added a gigapan mode that allows you to capture very large, multi-image panoramas. This feature is a welcome addition and works great – I will review it in detail in a future article.

In The Field With The eMotimo Spectrum St4 and Focus Fz Unit

To put the Spectrum St4 through it’s paces, I decided to film a mix of live action video and timelapse video at Niagara Falls. The following are my thoughts working with the Spectrum.

Setup and Ease of Use

I always find setting up and filming any video to be a hassle – tripods, batteries, cables a whole array of neutral density filters…etc. Adding in motion control and a slider just complicates the setup that much more.

I was primarily using four prime lenses in the field: the Nikon 20mm f/1.8, Sigma 35mm f/1.4 ART, Sigma 50mm f/1.4 ART and Sigma 85mm f/1.4 ART.

For timelapse photography I was using a Nikon D800 DSLR body. For live action video, I used both the Nikon D800 and a Sony a6300.

I had two minor issues setting up the Spectrum.

First, I found that no matter how tight I hand-tightened the Focus Fz rail clamp, it wasn’t quite tight enough and the gears on the Fz would separate from the gears on the lens with use. (eMotimo later advised that it is necessary to use the supplied allen key to tighten the clamp enough to keep it in place.)

Second, although the Spectrum is rated for cameras up to 12 lbs, with the large (and front heavy) Sigma 85mm f/1.4 mounted on the Nikon D800 the center of gravity of the load was too far forward. The Spectrum didn’t seem to have a problem moving the lens and camera around, but sometimes the lens would just randomly pivot down, ruining the shot.

To solve this I had to configure a T-plate to move the center of gravity of the lens and camera further back. I didn’t have this issue with any other lens/camera combinations – just with the big 85mm.

Once I had those two issues addressed, programming the Spectrum and dialing in my captures was pretty straight forward.

I have always liked the layout and format of eMotimo’s menu structures – it is pretty intuitive and fast to program in your shots.

Programming timelapse sequences with the Spectrum is a breeze – by far the easiest time lapse intervalometer and motion control setup I’ve ever used.

If you’re used to the Spectrum’s predecessor, the TB3, you’ll notice that the Spectrum’s menu is quite a bit more complex, but it doesn’t take long to get used to it.

The most difficult part for me was remembering what the buttons do on the Sony DualShock4 gaming controller.

I’m not a gamer so I don’t have muscle memory with a gaming controller – I have to look and mentally remember where the controls are and what they do – so when the menu says “Press X to Start”  – I have to look to see which one is the X button (which is one of the few controls that actually has a name!).

I think if you were used to a gaming controller, you would have a much easier time remembering what does what.

Pre-Planning and Intent

One thing that I really noticed with the Spectrum – especially when you’re trying to set up a four axis movement with five key frames, is that you have to be very deliberate with your shots.

When shooting live action video there were times when I though it would be a lot easier to just take the camera off the Spectrum, film hand held, manually pull the focus and stabilize the shot in post.

It was especially frustrating when I was rushing against sunrise, spending a minute or two to set up a 15 second live action video shot. For some reason, I was never frustrated setting up a timelapse sequence (when the shot was running for an hour, spending a couple minutes to set it up didn’t seem like much of a hassle) – but I did get a little frustrated programming live video.

I think the lesson learned is that the Spectrum is not for run and gun situations – it is for very deliberate pre-planned shots where control is more important than speed.

It took a little while to get used to filming live video with the live motion tracking mode – partly because I had to learn the controls and partly because it took practice to get a good feeling for filming subtle movements. However, once I got used to it, I very much preferred using the live motion tracking mode instead of the programmed shot mode for live action video.

I had no problem programming in timelapse sequences, so I think it really depends on what you’re filming.

Focusing With The Focus Fz

I primarily used the Focus Fz to pull focus during filming (I didn’t used it for aperture and just a few times for zoom) which raised an interesting issue.

With a DSLR you have to visually confirm the focus of your lens while using the Focus Fz. This is different from the usual timelapse work flow when you pre-autofocus and then lock it off.

If you’re used to filming video on a DSLR this might not be as much of an issue for you, but I found it really hard to manually focus by eye with the Focus Fz – especially when I was using a heavy neutral density filter and I could barely make out the scene.

(It is also really important to turn off auto focus, because if you accidentally autofocus your lens it will mess up the focus range you manually set with the Focus Fz.)

You can struggle with visual focusing with the Focus Fz on a DSLR – but to get the most out of it, I think you really have to use a camera that has focus peaking (or an external monitor with focus peaking).

I switched over to a Sony a6300 with focus peaking and working with the Fz was night and day. With focus peaking, I could see exactly where the plane of focus was and make much more accurate focus refinements with the Focus Fz.

This becomes increasingly important once you get into multiple point programmed movements – with focus peaking it is much easier and so much faster to nail your focus for each key-frame.

Conclusions and Recommendation

In my opinion the eMotimo Spectrum St4 is the best live action video and timelapse robotic motion control system on the market and the eMotimo Focus Fz really adds to it’s capabilities.

There is nothing else (that I am aware of) that will give you this many options  for robotic motion control.

Having said that, the Spectrum isn’t for everyone. Counter-intuitively, one of the biggest issues I had working with the Spectrum is that there are almost too many choices! You really need to have a certain level of comfort with the basics of video and timelapse before you try to add robotic 4-axis motion to the mix.

If you are just starting with timelapse, there are much simpler and less expensive motion control systems available that would be a better first step into the world of motion control. The Spectrum is really a professional level tool and if you don’t already know what you’re doing, it can be a bit overwhelming.

The same goes for live action video. If you are used to filming hand-held, on the fly, the process of working with the Spectrum is much different. If your interest is primarily hand-held live action video, you would probably be better off investing in one of the newer 3 axis stabilization gimbals on the market.

With a purchase price of $2300 for the Spectrum, plus another $425 for the Focus Fz unit and another $1000 or so for a compatible dolly purchasing a Spectrum is a significant investment.

If you think that you’re ready to jump into the world of robotic motion control, I would start with just the Spectrum itself, see what you can do with it, and then add on a dolly and Fz as your work progresses.

If you’re an experienced filmmaker or timelapse photographer – it doesn’t get better than this – you won’t be disappointed with the capabilities of the Spectrum – although you might discover the limits of your own imagination.

On the value for money side of the equation, it is difficult to really compare the Spectrum to anything else on the market. The Spectrum and the Fz are definitely built to last – and with eMotimo’s commitment to ongoing firmware upgrades, this isn’t gear that you’ll have to replace or upgrade anytime soon.

I think if you’re a working professional or advanced enthusiast and you know why you need robotic motion control for your work, I think the Spectrum would make a solid investment. It may not be something you will use everyday, but I feel like having a Spectrum in your gear closet would certainly give you an advantage over other film makers when the inspiration to create something impossible strikes.

What Do You Think?

Would you consider adding an eMotimo Spectrum St4 to your gear?

What shots do you think you might be able to capture the Spectrum that you can’t capture now?

Are there any features missing that might affect your decision to purchase a Spectrum?

Leave a comment below and let us know!