scanner options?

[White-Light]

I've been trying to record my DT40 projections this week with different cameras and I can't really get flickering to show up in the recordings. What I get is that "old tv/monitor screen" type flicker effect like in Pangolin's video, which is a lot slower. I have no idea why cameras capture them like that.

It's called rolling shutter effect.

You can see it clearly in my avatar where the shutter was at quite a slow speed caused by the low light.

http://www.diyphotography.net/everyt...olling-shutter

BTW if you really want to see it in action, try turning the brightness of your laser up and down whilst filming it. You'll find the amount of flicker or black marks or even tracing of the patterns varies according to the laser brightness + room brightness (it may be compensated for to an extent by the CMOS sensitivity). It's all going to depend on your camera. If you have a CCD, you shouldn't experience it but most cameras these days tend to use CMOS. As Swami pointed out below (this bit is an edit to add more info), the best solution if you have a camera with a manual shutter control, is to use it to lock the shutter speed at a speed that best suits the subject.

[swamidog]

set your camera to 30fps and 1/30th of a second exposure time, then adjust the iso and f-stop as necessary.

It's called rolling shutter effect.

You can see it clearly in my avatar where the shutter was at quite a slow speed caused by the low light.

http://www.diyphotography.net/everyt...olling-shutter

[White-Light]

set your camera to 30fps and 1/30th of a second exposure time, then adjust the iso and f-stop as necessary.

Thanks for the tip. Unfortunately on mine I have no choices its a fully automated compact. Best I can do is select the "scene" preset that works the best.

[cipher0]

The point that I tried to make in my video is that just because something is called "40 something" or even "40K" doesn't mean it can really do 40K

Okay. And you're absolutely right. From the info on their official site 36-38K. Still, calling it an overclocked 30K scanner sounds like an overstatement.

See folks all of this is about "feeling". "40" is more than "30" so perhaps there is a natural tendency to believe it's better even though I showed that -- at best, it isn't better and in many cases it's worst. Remember even the 24K test pattern I showed looked inferior on DT40s. Remember even the 30K pattern I showed looked inferior. And these were not at super-large angles either!

You've just shown what we already knew: better at wider angle.
They weren't "super-large angles", but they were still larger than 8.
Comparing them at that angle breaks the whole point of comparing the point rate. Dragon Tiger doesn't say their DT40scanners can do "40K" at large angles.

Honestly folks, as I mentioned in the past, *any* scanner can be tuned to go faster than it's really designed to go

If you don't mind overheating and breaking your scanners, then sure.

And BTW, in the video you said you DT40 performed better than you expected with some graphics, including test patterns. Was this the first time you were testing a DT40pro?

[Pangolin]

They weren't "super-large angles", but they were still larger than 8.
Comparing them at that angle breaks the whole point of comparing the point rate.

Yes, but I did compare them at 40K and you saw them. Aside from the fact that our scanners didn't have squiggly and wiggly lines, the actual pictures were pretty close. Probably the difference being indistinguishable by the "man on the street". But to speak directly to your point, WHO THE HELL OPERATES SCANNERS AT 8 DEGREES???!!!

Throughout the video we showed real graphics being displayed side by side at angles that people probably would use, not at tiny angles people wouldn't use. Don't you think that this is more valuable than "how fast a scanner can go at a small angle nobody uses"?

If you don't mind overheating and breaking your scanners, then sure.

It would be incredibly difficult to either overheat or break our scanners. Aside from the mirror, you'd be hard pressed to break one. I bet you can even run one over with a car and it would survive untouched. Train? Not so much ...

And BTW, in the video you said you DT40 performed better than you expected with some graphics, including test patterns. Was this the first time you were testing a DT40pro?

No, see, I've been working with scanners like this, and even specifically the DT40 for perhaps 10 years. When I said "I am surprised the scanners are holding together this well" I only meant that I was surprised that the DT40 was keeping up to our scanner (holding "together" -- together meaning like "paired with our scanner") as well as they did.

Bill

[absolom7691]

I bet you can even run one over with a car and it would survive untouched.

I'd rather you didn't! It was painful enough watching you pop a 520nm diode, back when they were really expensive when you were showing us the benefits of Lasorb!

I will also ask Keith's question... what are the beam dimensions of the 506 scanners with their block?

[Pangolin]

I will also ask Keith's question... what are the beam dimensions of the 506 scanners with their block?

Beam entrance is 0.715 inches.

Bill

[norty303]

I measured my block when I got it and the centre of the top galvo was 27mm from the bottom of the base.

[Pangolin]

Hi Norty,

I think he means the entrance of the beam, not the exit. I just checked it again with a digital caliper (since our Solid Works guy isn't in the office right now). It looks like 0.715 inches to me, which is a bit over 18mm.

Bill

[absolom7691]

Bill got it. I just wanted to know what diode mounts I will need to use for my future scansets, when they become available!

Thanks, Bill.