LCD Topgun distance requirements kind of crazy...

[postalp123]

Hello all,

Got my LCD Topgun in yesterday & installed it on my MAME cab along with Guncom (Excellent program BTW).

At first I had major calibration/tracking probs (Stuttering laser beam, gun going on & off, etc...) and I thought It couldn't possibly be that I was too close, I was a full 8' away! Keep in mind that I had the LED strips on the side of a 19" TV so they aren't that far apart.

So, finally out of frustration, I took another large step back to near 10+ feet total distance, and suddenly the gun works like a charm.

I'm happy it works, but 10' away from a 19" screen just to get good tracking/detection??? Just seems a bit extreme.

Anyone have any tips that help detection at closer distances? It's not unbearable.... but 10' is somewhat pushing the fun factor.

Thanks gents!

[horseboy]

Mounting the strips horizontally should help some.

[ahofle]

LOL, the guns should come with binoculars.

[horseboy]

I have read a lot on these things, but I haven't ever heard of someone having to stand that far back.

[rbarr110]

The guns sound pretty good with the exception of the distance, thats the only thing holding me back from getting one or two.

[horseboy]

According to Silver's TopGun Site and other a bunch of other stuff I have read the minimum effective distance you have to stand back is 2 times the width of the stands. So, on a 27" monitor with the stands mounted horizontally (about 17" apart) you can get away with being slightly less than 3 feet back. Not to bad.

I really need to hook mine up and test for myself. 

[postalp123]

According to Silver's TopGun Site and other a bunch of other stuff I have read the minimum effective distance you have to stand back is 2 times the width of the stands. So, on a 27" monitor with the stands mounted horizontally (about 17" apart) you can get away with being slightly less than 3 feet back. Not to bad.

I really need to hook mine up and test for myself. 

I appreciate the input, but fact of the matter is I'm well beyond 2 X the distance and thats the only place it works.

I'll try the horizontal approach however, thanks!

If it doesnt work, I guees I'll just rename "Point Blank" to "Pin-Point Blank" or just consider every game a "Silent Scope" game.

[ZeroPoint]

Hello, postalp123 !

Is your TV placed on a desk / table ? If so, try moving the front of the TV to the edge of the desk so there is free air below it...

My wild guess is that maybe the leds reflect in a "shiny" desk. This will force you to go further away and also loose accuracy !?

Any luck 

[Fozzy The Bear]

Mine work at 5 feet away on a 21" Monitor...... 10 Feet does seem to be extreme.

That said,  I'm now developing a wide angle lens system to fit on the front of the gun which should cut the distance to 2 Feet by making the gun think it's further away than it is.

Best Regards,
Julian (Fozzy The Bear)

[kiddk1]

Mine work at 5 feet away on a 21" Monitor...... 10 Feet does seem to be extreme.

That said,  I'm now developing a wide angle lens system to fit on the front of the gun which should cut the distance to 2 Feet by making the gun think it's further away than it is.

Best Regards,
Julian (Fozzy The Bear)

LMK im in

I had the same issue, my monitor is 21in and I had to recalibrate several times, light and IR lights can cause interference, I am now about 5 feet away

[RandyT]

That said,  I'm now developing a wide angle lens system to fit on the front of the gun which should cut the distance to 2 Feet by making the gun think it's further away than it is.

Wide angle lenses impart a "fish-eye" effect on the image which will change the relation of the LEDs to one another, possibly to the point that the software doesn't recognize the pattern anymore.  Moving the camera (gun) will also alter the pattern to something completely different from center as it is moved from side-to-side or up and down.

Worst case, it won't work.  Best case, really poor accuracy.  But I could be way off base, so prove me wrong  

HOTD3 is meant to be played close up to a big screen, not 9 feet away from a 37" tube (which is probably why I haven't played with the guns since I first got them)  This is the only flaw with these guns.

RandyT

[jjd]

Are there any bright lights behind you, overhead or otherwise?  It took me awhile to figure out that an overhead light was screwing with mine.  With the light on I can't get the guns to work unless I'm at the end of the cord.  With the light off they work from about 4 or 5 feet (21" monitor).

[kiddk1]

calibrate at night with all lights off and see if that helps, this is how I finally had to set up my led's

[Fozzy The Bear]

That said,  I'm now developing a wide angle lens system to fit on the front of the gun which should cut the distance to 2 Feet by making the gun think it's further away than it is.

Wide angle lenses impart a "fish-eye" effect on the image which will change the relation of the LEDs to one another, possibly to the point that the software doesn't recognize the pattern anymore. 

Not if you also include a fish eye correction lens in the system. That part of the lens system then distorts the image in the oposite direction. so the net result is apparent distance without distortion.

I'm still working on it...... The calculations and theory work on paper but I've yet to track down lenses cheap enough to make it a practical proposition.

Best Regards,
Julian (Fozzy The Bear)

[RandyT]

I'm still working on it...... The calculations and theory work on paper but I've yet to track down lenses cheap enough to make it a practical proposition.

That's why I assumed a single lense.  By time you pay for lenses, the housing to position them accurately in relation to one another, and a method to attach them onto the end of the gun you would probably be better off buying a real arcade gun and one of those expensive interfaces that are supposedly available to drive one.

I hate to say this (because it sometimes gives manufacturers more credit than they deserve) but you have to make an assumption sometimes that the manufacturer understood the shortcoming, but could not remedy it inexpensively enough to include a solution and still make the product marketable.  Not trying to dissuade you from trying, but 12 years of optics related manufacturing has left me skeptical about what can be done to fix the problem without specialized injection molded parts, a fair amount of trial and error, and possibly LEDs that are brighter than what are currently available.  A single lense will let you get away with a lot from a quality standpoint.  Multiple lense systems require much more accuracy.  More lenses in an optical system also tend to cut down the amount of light that gets through (unless they are quite large and made of very good materials).  Lots of potential problems, but few inexpensive solutions.

Then again, for the price of these guns and the method used, I'm pretty impressed that they work at all.  So maybe something is possible

RandyT

[Fozzy The Bear]

Then again, for the price of these guns and the method used, I'm pretty impressed that they work at all.  So maybe something is possible

I can only agree with everything you said in your post Randy. Technically it's possible, However, practically in terms of a system for sale to other people on here it probably isn't.

That said I'll always write up any practical results I get, so that other people can try it out if they want to. Assuming I can get it to work.

At the end of the day, that's part of why we do this stuff..... A lot of the fun is in creating things (and breaking things    . )

Best Regards,
Julian (Fozzy The Bear)

[MikeDeuce]

What about a fresnel lens, backwards? Or would that be worse than a fisheye?

[Fozzy The Bear]

What about a fresnel lens, backwards? Or would that be worse than a fisheye?

Wouldn't work at all Mike.... a fresnel specifically works by distorting the image, it's more of an optical illusion than a lens.... (given that it's actually rings of multiple different focal length). You'd also have to have a very large diameter one to get any result at all. So even less practical, but certainly cheap.

Best Regards,
Julian (Fozzy The Bear)

[postalp123]

A little more info on my situation:

Sorry about the crappy pic, I'm at work. As you can see, the TG's LED strips are attached to the sides of my 19" TV, and are directly behind a glass bezel, I have tried both with and without the glass bezel on to the same effect so the glass isn't my issue.



Not that I'm looking for any help, but I figured some of you might be interested in how I mounted these guys internally so they dont stick out like a sore thumb.

I'll get a real pic up tonight.

[postalp123]

Here are the pics as promised of the integrated LCD's:

[jjd]

If you are still having problems, it is due to the lighting.  I assume that some of the reflections shown on the photos are related to the camera flash, but there appear to be other light sources reflecting in the screen.  These WILL seriously degrade the performance of the gun.  Turn off all light sources that may reflect in the screen and try the gun. 

I would bet that you will be able to get closer and the gun will work better.