Accuracy of pointer on hi-res screens

This is the place for comments, criticisms and even the occasional compliment related to the SmartNav drivers and profiler. Also the place to discuss and review support issues.
garygfx
Posts: 6
Joined: Sat Jan 28, 2006 5:00 am
Location: UK

Accuracy of pointer on hi-res screens

Post by garygfx » Sat Jan 28, 2006 9:31 am

I noticed the resolution of the camera is pretty low, so I'm wondering how accurate the control of the mouse pointer is on a hi-res dual monitor display such as 1280x1024. So in total I have 2560x2048 pixels of real estate for my mouse pointer to travel.

I've calculated that 1 pixel in the camera accounts for a grid of 7x3 pixels on my screen. So in theory pointer control can't be more accurate than coming within 7 pixels of the exact position I want. This could make it impossible or very tricky to position the pointer between 2 characters in a text editor where each character is 5 or 6 pixels wide.

If you've done something clever to compensate for this or if I've misunderstood how it works then please let me know. I'm a programmer and web designer so I need fairly accurate control although I won't be doing any drawing with SmartNav. It will be mostly positioning the pointer for code editing and using software like Dreamweaver.

Thanks in advance for your help.

[ January 30, 2006, 03:57 AM: Message edited by: GaryF ]

Birch
Posts: 1139
Joined: Thu Jan 30, 2003 5:00 am
Location: Corvallis, Oregon

Re: Accuracy of pointer on hi-res screens

Post by Birch » Mon Jan 30, 2006 7:22 am

There are two ways in which the SmartNAV is able to provide cursor control at a resolution much greater than its camera image size.

First, the objects it tracks are typically much larger than a single pixel (between 50 and 500 pixels), this allows it to compute the averaged and weighted center of the object which typically falls "between" pixels yielding "sub-pixel" resolution.

Second, the cameras sample at a very fast frame rate and then apply user adjustable smoothing to the tracked cursor position. This also results in increased precision and additional "sub-pixel" resolution.

An additional feature called "precision mode" is available which allows the user to assign a hotkey which will temporarily zoom-in providing greater precision with reduced range of movement.

If you are unsure if the SmartNAV is right for you, we recommend trying the product out at no risk with our 30 day return policy .

garygfx
Posts: 6
Joined: Sat Jan 28, 2006 5:00 am
Location: UK

Re: Accuracy of pointer on hi-res screens

Post by garygfx » Mon Jan 30, 2006 9:02 am

Thanks for the prompt and helpful reply, Birch. I've found a UK supplier who will give a 14 day return policy. I guess US customers have the advantage of buying from the manufacturer and at cheaper prices!

Thanks,
Gary.

[ January 30, 2006, 04:15 PM: Message edited by: GaryF ]

seanav
Posts: 4
Joined: Wed May 10, 2006 5:00 am
Location: United Kingdom

Re: Accuracy of pointer on hi-res screens

Post by seanav » Wed May 10, 2006 1:20 am

Hi who in the UK mate?

Birch
Posts: 1139
Joined: Thu Jan 30, 2003 5:00 am
Location: Corvallis, Oregon

Re: Accuracy of pointer on hi-res screens

Post by Birch » Wed May 10, 2006 10:21 am

quote:Originally posted by seanav:
Hi who in the UK mate?You can check our list of Authorized Dealers, it is a good starting point for international customers. http://www.naturalpoint.com/smartnav/co ... alers.html

[ May 10, 2006, 05:22 PM: Message edited by: NaturalPoint - Birch Zimmer ]

garygfx
Posts: 6
Joined: Sat Jan 28, 2006 5:00 am
Location: UK

Re: Accuracy of pointer on hi-res screens

Post by garygfx » Wed May 10, 2006 9:48 pm

I got mine from www.keytools.com. I sent it back within 14 days for a refund as it gave me terrible neck pain (even though it was way cool and clever!). I'm otherwise able bodied and healthy but was trying to find an alternative to using my hand for the mouse as it gave me bad RSI and CTS.

If anyone else suffers from RSI/CTS you can get some good tips from reading this story: http://freshmeat.net/articles/view/407/

By reading this article I realised that I was subconsciously putting way too much weight/pressure on my arm - I sat at the computer with my hand constantly on the mouse putting lots of pressure on it which is likely the cause of my problem. Hope this helps someone else.

Gary.

mips
Posts: 2
Joined: Fri May 12, 2006 5:00 am
Location: San Diego, CA, USA

Re: Accuracy of pointer on hi-res screens

Post by mips » Tue Sep 05, 2006 2:32 am

I'm using SmartNav daily on a dual monitor system with resolution set to 1600x1200 and have absolutely no problems. If you're slow and concentrated enough, you can control the cursor position pixel-accurate even on this 3200x1200 area even without using the "precision" key.

I have the SmartNav camera positioned on one of the monitors near the middle between the two. I use two dots on either side of my glasses so that at least one dot faces the camera as I turn my head. The tracking software can switch between tracking targets smoothly. The SmartNav control panel has a tracking view which shows what the camera is seeing and which object it is currently tracking.

rogere@Rmegen.net
Posts: 1
Joined: Mon Apr 14, 2008 7:48 am

Re: Accuracy of pointer on hi-res screens

Post by rogere@Rmegen.net » Mon Apr 14, 2008 7:58 am

Very interesting product and encouraging testimony on dual 1600x1200 operation.

How about SmartNav (I guess it is NaturalPoint sw) operation with triple 16000x1200 positioned side by side (4800x1200)?
I would estimate the viewing angle from 0,0 (left pixel) to 4799,0 (right pixel) to be around 30degrees from nose.

Can one just scan around all three monitors with one camera?
Does one SmartNav cap work across all monitors?
What about the two gaps between monitors?

Is there a tech note on such an installation?

Thanks for help.
Roger Ellingson

VincentG
Posts: 7728
Joined: Mon Jul 17, 2006 5:00 am
Location: Corvallis, Oregon

Re: Accuracy of pointer on hi-res screens

Post by VincentG » Mon Apr 14, 2008 11:21 am

Basically, as long as the desktop is seen as one big screen, the SmartNAV will work across all of them.

The only thing that you might have to do is have the camera a little farther back, as well as increasing the spped of the cusrsor movement as well.

homagetogorto
Posts: 5
Joined: Sun May 13, 2007 11:20 am

Re: Accuracy of pointer on hi-res screens

Post by homagetogorto » Fri Apr 25, 2008 7:51 pm

Here are my experiences and thoughts about using SmartNav with multiple displays. This is after nearly 2 years of use. What prompted me to come here today is that my SmartNav 4 just arrived, and the increased tracking is *fantastic* for multiple monitors.

My desktop is 3968x1280, and the SmartNav works great. For a while, it was 4544 pixels across, and that worked great too. I sit 30 to 40 inches away from the camera. It does take a bit of practice and tweaking of the speed/smoothness/acceleration settings to get accurate control when you have this much real estate, but it can be done.

I've just switched from a PC to a Mac, and a SmartNav 3 EG to a SmartNav 4 EG. I use a 3-pedal USB footswitch for mouse buttons, and I have another single pedal attached directly to the SmartNav.

On the PC, I used the 1-pedal switch connected to the SmartNav to pause/unpause tracking. With the tracking speed set so high, I found it beneficial to pause tracking before I clicked on something, so that I didn't accidentally move off the target while I was clicking. But there's also precision mode, which you can trigger with a hotkey or a pedal.

On the Mac, there isn't a precision mode per se, but you can use voice commands or right-click on the dock icon to select built-in slow, medium, fast, or custom settings. So slow mode would be the equivalent of precision on the PC. And on the Mac, you can't make the pedal pause tracking, but you can still create a hotkey to pause, and I might be able to reprogram my USB footswitch to send that key sequence. (I only hooked up the SmartNav 4 to the Mac today so I haven't quite worked this out yet.)

Also, on the Mac, the UI won't let you specify high enough speeds for multiple displays, but you can use 'defaults write' in terminal to edit the plist to go higher than the UI allows. This is probably technically unsupported, but it was RJ and his developer who told me how to do it. The UI goes up to 70 and I've got mine set to 120 horizontal x 100 vertical. (It's a different scale than the PC version.)

Sitting so far from the camera, with the SmartNav 3, I had to order the "raw material" reflective strips, and cut myself 1"x1" squares. Otherwise, the camera could lose sight of the dot. But with the SmartNav 4, I can use the standard small round dots just fine. I have to go about 60 degrees off-center before it loses track of me -- meaning, it can follow me through a range of about 120 degrees at 30-40" from the camera.

Wow, I can get about 6 feet away and the SmartNav 4 can still see the little dot! So, get big dots or a SmartNav 4 if you're sitting more than 24" from the camera. The tracking on the SmartNav 4 is so good that maybe it's time I got more and bigger monitors!

As for the gap between monitors, SmartNav treat that the same way your mouse does -- in other words, it will pretend it's not there. Even in absolute mode, you don't even notice the gap.

I think you need an EG to hook pedals to the SmartNav, and I'm not sure if you need an EG or AT for speech.

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