To the laser show software companies

[norty303]

Well I think you could use most amps you like.
Thats why I asked about the DT amps earlier. Does anyone know if the DT30 and DT40 amps are the same, and the galvos different, or is it the amp that differs (or both!)?

[m0f]

I don't really know the answer, but in looking at the dt30 and dt40's side by side, they really appear to be exactly the same. I can't spot any physical differences. Which makes me wonder if maybe they're just binned based on how they perform..

[planters]

I suspect the amps matter quite a bit, although maybe not for close cousins such as the DT30 and DT40. These may be identical and one is under utilized and the other driven to the max . But in any case, one argument for the advantage of the new Pangolin scanners is their power handling capability. They are low inductance and low resistance and to perform better they are able to utilize higher driving currents. Remember when Eye Magic went from the 4000 series to the 7000 series(then the 8000 series then...)? They required a more powerful power supply. I think if you used a DT 30 amp it might restrict the performance of the 506 to near DT 30 level performance.

Just another note: I recently measured the divergence of a single color (red) from the aperture of my projector so, every optic was tested including the un-driven scanner. At 10 M the spot was 7mm square and so quite nice. Then I measured the beam widths of the test pattern and in both the X and Y the widths were 15mm. I am pretty sure this is due to tracking variability, jitter and pointing errors present in the low cost DT scanners. I do not know if it is the motors or the amps, but one problem I am looking for these new scanner systems to solve is this deterioration of hard won, tight beams.

[norty303]

I think if you used a DT 30 amp it might restrict the performance of the 506 to near DT 30 level performance.

Personally, I am not looking for stellar performance. I tend to under drive my DT30's by quite a way, as a safety margin, and the fact I do mainly beam shows.

However, my forays into abstracts and the like mean that I'd really like to run much closer to 30k than I do now. But I worry about the DT30 galvos. So dropping in some 506's seems like a way of getting some safety margin, even if the limiting factor is the amp at that point.

[colouredmirrorball]

In my memory, DT30's were originally DT25 galvo's with the DT40 amps, thus increasing performance. Don't quote me on that.

[The_Doctor]

Just another note: I recently measured the divergence of a single color (red) from the aperture of my projector so, every optic was tested including the un-driven scanner. At 10 M the spot was 7mm square and so quite nice. Then I measured the beam widths of the test pattern and in both the X and Y the widths were 15mm. I am pretty sure this is due to tracking variability, jitter and pointing errors present in the low cost DT scanners. I do not know if it is the motors or the amps, but one problem I am looking for these new scanner systems to solve is this deterioration of hard won, tight beams.

Small amounts of jitter I can probably live with, but can you tell me if you've seen something particular and far more obnoxious? Described here, with an AVI file to show it:
http://www.photonlexicon.com/forums/...087#post277087

[m0f]

It that intended to be a single rotating line and warping into two slightly curved lines? If so, that's something I've never see with my DT's. Have 1 set of wides, 3 sets of 40's and 2 sets of 30's, and have never seen anything like that. Generally I find they're pretty accurate. Could it be a tuning issue ? (Edit, or as it seems to affect both x and y, grounding issue ? For reference I do run mine without the ground wire connected, and also the scanners themselves are mounted on plastic standoffs to prevent grounding through the case. Though I just did that to keep signal and power grounds isolated.)

Out of curiosity I'll have to measure the line width for jitter, but there's none that I've visibly noticed with any of my sets. Lines look nice and thin, but perhaps measuring may show differently though. Definitely has me curious now.

[The_Doctor]

Nope, it's intended NOT to be a single rotating line and warping into two slightly curved lines. If it would behave itself and look like an ideal straight line turning about its midpoint, even when unblanked, I'm pretty sure I can trust the scanners to do what I want, at least till their little bearings cave in. The trouble with my WideMoves is they ALWAYS did this horrible thing, and it's put me off buying scanners. I will never put money down again until I know I will not be faced with this when I do.

Edit:
I asked Bill (Pangolin) in PM about this, but I got a terse three-line statement that means basically that unless I used Skype he wasn't going to talk to me. I don't know why. He suggested email in the public post, but in PM said he hates long emails. Mine wasn't long, not a lot longer than the length of this post. Anyway, the point of this is that if a person wants me to buy scanners from them, they MUST answer this question. And if they do not care to do this, then I will buy my scanners from someone who does. I'm not that fussy, so long as I do not see such an extremely objectionable problem at the outset, because it's a lousy way to embark on a long and expensive course of action.

Anyway, if anyone is willing to set up that rotating line thing on their projector and let me know the outcome, I'll be very pleased to see the result. Right now I'll accept any help I can get to resolve this.

[planters]

I also think that Bill would have recommended the best driver choice available at this time for his scanners. He is upfront about the low cost of the motors. I do not think he would be completely unaware of the rough cost of the Micro Amps. I am going to try this package unless, when Justin responds to my email, he leads me to think the "credit cards" will be ready by Jan. The question I still have for Bill is whether these Micro Amps are a compromise in functionality. The small size of the "credit cards" is not important to me.

One point Bill made in his response to Jon in post #151 was about the low drift version of the 506 or pro version. I am concerned that my low cost DTs are deteriorating the quality of my beams. Would it be necessary to use the pro motors to avoid tracking or pointing errors on short time scales or only for long term drift. Would the driver choice need to take into account the 506 model chosen?

[m0f]

Hmm, might be worth trying to isolate the ground. One thing I noticed was that signal ground for the scanners travels through the scanner body into the baseplate. In my builds it was the only thing that was connecting signal and power grounds together. It seems to be I ended up with a nice scan after isolating that, but I can't say I ever had anything that bad..