New EYEMAGIC Scanners EMS7000

[Solarfire]

Thanks j4cbo, I figured it would be somthing like that, but isn't that like trying to judge a speakers performance by just listening to it @ 30kHz or something like that? A scanner system is more or less a closed loop speaker. Excuse the anology to speakers, i have a history in speaker development which kinda fits into the subject at hand.

[kecked]

I have to say I have 6215 scanenrs and I doubt they could be much better. I know Bill from many years of interaction and he has never once not given great advice and guidance. The only things I could see that could be better would be physical size of the scanners, heat disipation, ability to use bigger mirrors and still have the same perfromance and of course price. On the driver side it doesn't matter anymore. I doubt I'd ever have to retune these scanners and if I did I'd need a phd and a lab to do it. Thus if Bill really is making better scanners these are the items I'd look to see improved on. I for one am totally happy with what I have and would not switch over unless his are doing 1200mps or something crazy like that that would allow actual raster TV using laser at 1080p. I bet that is coming but it will be a mems resonant device or such.

[heroic]

I have to say I have 6215 scanenrs and I doubt they could be much better.

Things that could be improved about 6215s (yes, I have a set of those too, as well as DT40 Wide, EMS4000s and 6800HPs):

- the analogue scanner amp is kinda lame, a DSP could do a better job
- higher field magnets (there are high temperature NdFeB magnets available now)
- lower impedance coils
- smaller rotors (due to 2 and 3 above)
- fully digital interface (SPI or I2S)
- full H-bridge drive, rather than bipolar rails
- class H output architecture for lower power

Most of these features *are* available in CT's range, just not for laser show apps due to the ILDA spec being twenty years out of date.

[heroic]

Thanks j4cbo, I figured it would be somthing like that, but isn't that like trying to judge a speakers performance by just listening to it @ 30kHz or something like that? A scanner system is more or less a closed loop speaker. Excuse the anology to speakers, i have a history in speaker development which kinda fits into the subject at hand.

No, it's more like trying to judge a speaker by listening to a specific piece of music- the ILDA test frame contains features that allow the measurement of several different facets of projector performance. The circle feature tests the impulse response of the galvanometer system, and the dots below it test the blanking performance of the projector. Meanwhile the frame around the outside tests the orthogonality of the axes and the square shape tests the gain calibration.

It's rather like testing the setup of a CRT using a well defined test image like Test Card F. When done properly it is quite revealing.

[kecked]

All true I guess. I'm no expert in this discussion. I just mean to say I am really happy with the 6215's. They are a class act and good enough for me well into the future. I had the ems-1000 or 2000 not sure which was the first ones and I traded up to 6800's that had pretty beat bearings as Bill can attest. He took a look at them for me to see if they could be salvaged. And the 6800's in that state kicked the butt off the the ems scanners. I'm sure they have gotten a lot better in the last 10-15 years but the difference was staggering when I got the 6215's. One last comment and I leave this discussion. I actually liked the 6800's in some ways better as it rounded off some images and made them "look" smoother. Not saying I'd go back but everything is a trade off.

[colouredmirrorball]

No, it's more like trying to judge a speaker by listening to a specific piece of music- the ILDA test frame contains features that allow the measurement of several different facets of projector performance. The circle feature tests the impulse response of the galvanometer system, and the dots below it test the blanking performance of the projector. Meanwhile the frame around the outside tests the orthogonality of the axes and the square shape tests the gain calibration.

It's rather like testing the setup of a CRT using a well defined test image like Test Card F. When done properly it is quite revealing.

That reminds me of that one song I made that starts with a simple sine wave at a low frequency, and after a few seconds I throw some other wave forms in it. It's inaudible on bad speakers such as cell phones and laptops but notable on good audio systems. It's great for testing out sound systems =D
[Shameless plug to the song: http://soundcloud.com/lj-florian/polyphonic-synth-crap ]

I'm having difficulties following this conversation... could someone link me up to a few useful read ups?
Like, what's a torque constant? What is Giga-meters convolution product centimeters times two? (:P)

Meanwhile I'm pretty satisfied with my DT-30's, but that doens't say much as my previous scan system was a seriously detuned 12k set...

[Bradfo69]

As to where everybody else is, good question. Has anyone not gotten theirs yet?

I purchased two sets of the EMS 7000's and my power supplies just came in a couple weeks ago. I traded one set to dsli_jon and am waiting to hear if he's had a chance to test them yet. I have not done a thing with mine as I am still waiting to pick up a red module to finish a project that these are likely going to go into. So, there's your answer as to where some of the group buy is tied up.

[White-Light]

No, it's more like trying to judge a speaker by listening to a specific piece of music- the ILDA test frame contains features that allow the measurement of several different facets of projector performance. The circle feature tests the impulse response of the galvanometer system, and the dots below it test the blanking performance of the projector. Meanwhile the frame around the outside tests the orthogonality of the axes and the square shape tests the gain calibration.

It's rather like testing the setup of a CRT using a well defined test image like Test Card F. When done properly it is quite revealing.

Yep. Pangolin have this summarised in a simple image:




Correct:



Too fast:



Too Slow:




I think also what needs to be born in mind is the scan angle. Most scanners can do higher speeds if the angle is small enough. The real test is whether or not they can achieve a perfect pattern at around 8 degrees.

I don't know what EMS 7000 can or can't achieve, something beyond my knowledge or interest.

[Solarfire]

Thanks for all the Input on the kpps question everyone.

I don’t want to get of the subject here but just one last opinionated statement. Being the way I am, questioning things that don’t totally make sense to me, I researched a little more on the subject of the kpps/ILDA pattern question. Well it turns out that my speaker analogy was spot on and the ILDA pattern at best is a compromise made at a time when 60k scanning was somewhere in the far future. The bottom line of what I’ve found is that tuning scanners to reproduce the ILDA pattern as intended, just means that the scanner is tuned to reproduce the ILDA pattern, it therefore says nothing as to how well the scanners will reproduce other complex graphics at different scan speeds.

The main thing that bothers me about the ILDA pattern is the fact that the scanned image is supposed to display the circle inside the square. This is actually a distorted output of the input signal where the square is in the circle. IMO this makes no sense whatsoever. For my understanding of positioning systems or PID controls, output should equal input. Scanners tuned in this manner, must be prone to also distort other complex images.

It seems to me that when the ILDA pattern was developed someone leaned towards the static test pattern of a television which has no moving mass, thus the static image. IMO for tuning a moving mass a dynamic signal, covering a broader bandwidth of a given frequency range would much better linearise output over a broader range of scan speeds. As with speakers, the goal is to be linear in output over a given frequency spectrum.

I don’t know… just my 2 cents worth?

[planters]

I agree. If the major criterion for comparing and pricing scanners is a test that contains idiosyncratic distortions, then unless a show consists of graphics that are closely related to this or a few other graphics the performance will be less predictable. What about a table of several important values such as resonance, maximum sustained angle x speed product, pointing accuracy and maybe just a few others. If kpps is also quoted then no harm and useful as a familiar benchmark.