DT40 scanner problems

[dave]

I think you will want to follow this Andy

http://www.pangolin.com/userhelp/return_shipping.htm

[Mr.Coffee]

Wow, being a newbie, the last thing I would have wanted to do once I got my projector up and running was try to figure out why the image looked like crap. needless to say, tuning would have been a daunting task. I consider the end result well worth the shipping. (and that's for express both ways to korea).

I showed the before and after images, as well as your dt40 mod PDF to some of the guys here at work,and they were all very surprised that you don't charge for this mod. I'd just like to say, Thanks again for the help!

[Pangolin]

@Dave:

Yes, what Dave wrote is correct. We always like people to use that form when sending hardware to Pangolin. It has great information on how to declare and ship things, and a return form so that when we receive the gear, we know what to do with it.

@Mr. Coffee:

Glad I can be of service. The initial analysis, mod, and post tuning only takes a few minutes, so we don't charge anything for it. I would rather there be good images in the industry, no matter who they are being presented by. Bad images are always bad for the whole industry, and in a strange way, bad images, even when all the way in over in Korea could hurt Pangolin all the way over in America...

Best regards,

William Benner

[jian725]

why the image looked like crap.

I all through advertence this topic.

Now I have to say:If DT scanner like crap,then most Chinese scanneras not as good as crap.

Maybe someone buy the Photolaser's scanner or PR-laser's scanner and let Bill try to re-tuning .They will know what is crap.

Why we still not action to improve the driver?

In our standpoint improve the galvo MORE important.The driver of parts are semiconductor.If the driver incessant runing at 24hoursX365 also no any problem.
But the galvo in existence mechanical movement.If CTs also runing at 24hoursX365. at the same time I also can't believe CTs working same at the starting of state.

Most scanner of malfunction come from galvo,NOT driver.

So our working most improve the galvo more stabilization durable and quality.
Even though the driver not complete perfection.But we will improve it later.

We doing the best!

Jian

[carmangary]

Speaking of photolaser, which I think you mean Canton Laserphoto, which is also Laserpic - I looked at their scanner amps and compared them to the DT40 scanner amps and they look practically identical in terms of the components onboard. I haven't actually checked checked to see that the schematic is the same but I bet they are pretty close if not the say. The galvos even look the same. Are all chinese companies copying from the same reference design? It would be hard to believe that the similarities are by accident.

[buffo]

Hey Jian;

You sound upset. Please don't be. I honestly believe that Bill Benner's comments are meant to help you improve your product, not to insult you.

We understand that you are working on improving the mechanical efficiency of the scanner itself. And I agree that it probably makes more sense to get the mechanical parts perfect before you try to make the electronic parts perfect.

But Bill's advice about how to tune the galvos is important. Many new people do not know how to tune their galvos, and a lot of them are afraid to even try to tune them. So it is very important that the galvos be tuned correctly before they are shipped. This is something that you could take care of very easily.

All of the DT-40 owners that I have talked with are very happy with your scanners. Yes, most of them had to tune their scanners when they first got them, but once that was finished, they were very pleased with the performance. None of these people are calling your scanners "crap". (If we thought they were crap, we wouldn't still be using them.) I think you just misunderstood what Dr. Coffee was trying to say.

Adam

[Pangolin]

Hi Gary,

Yes, almost all Chinese scanners are based on the original Cambrige 6800 that was made in 1992, and also all Chinese scanner amps that I have ever seen are based on the Cambridge model CB6580 scanner amp design, of which I participated in, also back in 1992.

The funny thing is, when you talk about "reference designs" some Chinese companies don't even have the schematic for their own scanner amp!! All they have is a board layout and parts list. I won't mention any names, but lets just say we wouldn't have to think for very long to come up with brand names...

Regarding my amp mods, they are intended to improve the visual output that everyone winds up seeing. At Pangolin, we take a "Vidal Sassoon" approach to things. If Jian's scanners don't look good, then Pangolin software projected through Jian's scanners won't look good... So it's very important to us that everybody's scanners look good, regardless of who's software is actually driving them.

Let me digress for a moment and tell a story. A friend of mine was standing in line at a popular theme park. He actually was one of the people who created the laser show running at that theme park. While in line, he started talking to some girls who were also in line. He asked them if they were going to see the laser show at this theme park. The girl replied "naaaa. My friend saw a laser show once, and she said it wasn't that great".... WHAT?? Friend saw A laser show ONCE?? And IT wasn't that great?? It wasn't even that her friend had seen THAT laser show -- just some other laser show put on by some other company at some other venue, and it ruined this girl for life in terms of seeing laser shows. THAT HAPPENS MORE THAN YOU MIGHT THINK!!!

So we are very interested in all laser shows looking as good as they can, even those from competitors.

But getting back to my mod, if you take a look at the document, you will see that it actually involves REMOVING components. The components that we recommend being removed actually improve reliability (whenever you reduce the "moving parts" you increase reliability) and also make the scanner amp easier to tune. This is important, not only for end-users (Frankly, Andy would have a fighting chance of tuning his own scanners if it had my mod) but also for Jian, who, theoretically should be able to tune scanners...

Things should always be looked at from a "system" standpoint. If improvements can be made to the system, they should be made. My mod is just such an improvement.

As for comments about improving the scanner itself, I am afraid that Jian is headed in the wrong direction... I do before and after plots of every scanner using our DSA. When I get to the office I will post plots of a DT-40 from long ago, one from more recent, and one from the most recent batch. You will see that the ones from the most recent batch show numerous resonances, which is illustrative of poor manufacturing process.

Jian, if you can remember how you made scanners around a year ago, I recommend you switch back to whatever you were doing then, because your scanners back then didn't have these resonances... (However, from a system standpoint, if you do my mod it tends to mask the resonances anyway...)

I am only hear to help, and companies in California pay me big money to offer them servo advice. Also, I recieve scanners from all companies around the world, asking my advice for improvements. Companies who take my advice do well, and companies that don't, don't do as well. Sorry, those are the breaks and that's just how it is... If you don't want to take my advice, believe me, you won't be hurting my feelings!! But you will be hurting the success of your own company!

Best regards,

William Benner

[DZ]

So we are very interested in all laser shows looking as good as they can

Too bad nothing can be done regarding poor programming of graphics shows... I've walked out on several planetarium laser shows that were just very poorly put together.

Just curious, Bill, have you ever tested one of Jian's older DT-40's? I still use them in my projector and they've performed great. I've only had one issue with a fuse going bad on one of the drivers.

I eventually need to put the DT-40 pros in, just can't seem to figure out where they've run off to!

[Mr.Coffee]

Jian, I was certainly not calling your scanners crap. there has definitely been a misunderstanding. I have no basis for comparison to make such a claim. I was stating that the un-tuned image looked like crap, and that the tuned image looks much better,that's all. as for my scanners, I can't wait to get them back with the fb3 so I can finally start using them!

think about it this way, a shelby gt500 will run like a dream, but won't work well at all if you don't tune it's engine up properly. nothing wrong with the machine itself, just a few of the settings.

[jian725]

Jian, I was certainly not calling your scanners crap. there has definitely been a misunderstanding. I have no basis for comparison to make such a claim. I was stating that the un-tuned image looked like crap, and that the tuned image looks much better,that's all. as for my scanners, I can't wait to get them back with the fb3 so I can finally start using them!

think about it this way, a shelby gt500 will run like a dream, but won't work well at all if you don't tune it's engine up properly. nothing wrong with the machine itself, just a few of the settings.

Hi Rhys ,
Sorry for my misapprehend.

Some good friends give me a correct.
Jian

Hi Bill,
I am sorry.
I still in holiday with my family.
So busy than workday.
I will reply to you later,let you clear my standpoint.
Jian