Kensingtons DPI Sucks Donkey Balls

[sndstrm]

I'm using the Kensington Orbit w/ Scroll Ring
http://us.kensington.com/html/17531.html

It took almost exactly 1 revolution to move across my screen at 1920x1080 at 6/10 mouse speed on Win7.

I'm not necessarily disappointed in this trackball, I actually like it pretty well and I got a killer deal on it.  However Kensington has definitely been slipping on their trackballs the past couple years.

[sndstrm]

The next pc purchase im going to make is the CST LaserTracX.  I have been drooling over it for a while and its time to take the dive.

[BucklingSpring]

This guy seams to know what he is talking about
http://home.comcast.net/~richardlowens/OpticalMouse/#resolution

One section got my attention:

   Resolution (counts/inch)

The resolution of the mouse is determined by the optical properties of the focusing lens and the physical size of the image sensor. The mouse resolution is then further modified by the driver software on the computer, where the sensitivity of the mouse can be decreased by ignoring very small movements or increased by jumping more than one pixel on screen even though the mouse only moved one pixel on the desk.

The optical resolution of the mouse is usually given in CPI (counts per inch), but can also be given in pixels per inch or (somewhat erroneously) in DPI (dots per inch). Just keep in mind that this is how many optical sensor pixels per inch the camera sees, not how many screen pixels the pointer moves per inch of mouse movement.

The main advantage of higher resolutions is that the minimum physical distance needed to register as a mouse movement goes down. Usual mouse resolutions are 400 or 800 CPI.

Would have been nice if The stats had included the Kensington trackballs too.

[BucklingSpring]

From Kensington Support

   Dear Customer:

Thank you for contacting Kensington Technical Support.

We appreciate your interest in Kensington products. We understand that you are looking for the details and specifications of the Expert Mouseฎ PS 2 Serial model #64215.

In this regard, we request you to find the manual attached with this E mail.

We would also like to inform you that the DPI of the Trackball is 1000.

Please Read This!

Kensington Technical Support incidents are only processed via our support web site, not via email.  Please do NOT reply to this email, but rather you must click on the link below which will bring you to the Kensington Technical Support web portal where you can initiate questions, modify your active incidents, or perform maintenance on your support account.

Again, please do NOT respond to this incident via email, please click on this link to access your support incident.  Thank you.

Kensington Computer Products Group

Regards,

The so called attached manual is just marketing crap with no specs what so ever.

[BucklingSpring]

I'm rocking the 3200dpi CST now.

.2 of a spin to cross 3760 pixels.  Sounds about right.

 
Now set the trackball software any way you want or any other software for that matter then try to move the trackball 1/3200 of an inch and tell me if the cursor moves ;-)

I don't care if it crosses the whole screen, I'm happy as long as it moves.

- The good thing about Trackballs is that the result will not depends on the surface of the mouse pad.
Once I have deciphered the Trackball communication protocol. I will count how many directional packets were sent during about an inch of movement.

I think high DPI is overrated. My Razer Lachesis can crank up to 5600 dpi, but does the mouse pad surface can actually provide that granularity?
I don't even beleive we can control our motion to the 1/3200th of an inch anyway. I suspect polling speed (baud rate) is much more important than DPI, especially for a gamers who move fast on fairly long distance (couples of inches per say...)

[BucklingSpring]

Would anybody like to contribute to the Trackball Wiki by posting results?

Once I figure out an accurate/reliable methode, I will post results for all my Kensington Trackballs.
Ranging from the Expert Mouse 5.0 of the mid 90s to the recent Optical Expert Mouse, with couples of Orbits in the middle.

[BucklingSpring]

Hahaha - competing TRACKBALL wikis.  Talk about a subsegment of a market.

It's like two people on a desert island arguing all the time.

Just set the mouse sensitivity to 6/11 and roll the ball please.

3200 DPI ROCKS!!!

300 DPI doesn't.

 
LoL... I like the spot you chose for our honeymoon(*) vacation ROFL...
When will you propose?  (*hint - I'm not attracted to guys)

The mid 90's Kensington were likely 400dpi
The later slit-wheel, optico-mechanical Kensingtons were likely 800dpi (Expert Mouse Pro)
I have no clue about the later true Optical ones. Opening them and looking at the sensor chip may give it away.

With our passion for trackballs we are indeed alone on that island.

No promises, but I will even compare the results between your protocol and mine.
Keep in mind that I'm getting a life back, starting Monday with real work.

[BucklingSpring]

If you're not going to help you can go away now.

Will you be this argumentative at work?

 
I'll take the next boat.

I might, depends what is at stake.

Here I take any occasions allowing me to add few cycles on the XArmor keycaps to see if they're going to wear.
Plus I always like a good challenge. Proving you wrong is certainly not an easy task.

[BucklingSpring]

Technically you are not threadcrapping since this is not the Classifieds but you are definitely threadpooping.

Go away.

 
I'm pooping when I talk about anything off topic. Thus I have sinned... Throw me stones.

I'm realistic and dead on topic when I challenge the way you measure DPI.
But who gives a sh!t if a trackball from the 90's (Kensington EM or CH DT225) does 400dpi or 3200dpi or if the 2010 model only does 1600?

"A wiki enables communities to write documents collaboratively. (...) A wiki is essentially a database for creating, browsing, and searching through information. A wiki allows for non-linear, evolving, complex and networked text, argument and interaction."

So we will have a trackball wiki… Now we just need to find a community.

"Kensingtons Expert Trackball and SlimBlade Trackball DPI Sucks Donkey Balls"

Is a bold statement and no science to support it. By pooping on your statement, I gave it more attention than it deserves. I guess folks who gave so many awards to the Kensington trackballs had something else in mind. Plus I have been a Kensington fan for quite a while. (Big balls Kensington... Never really liked the Orbits)

Our beloved keyboard wikis are closely tied to the specs of the moving parts and electronics behind it.

If you like your trackballs so much, why don't you use the same rigor and highlight the brand and model of the sensors with the documented specs from the manufacturer?

We're told MX switches are good for 50M cycles. Did any of us proved it with arbitrary techniques? No… We just post what Cherry says about it.

I say find the brand and model of the trackball sensors and report back the official specs about them.

Light the fire, I think I see a boat.

Sorry Ripster, I didn't say goat…

Lets have a Missile Command challenge to set the record straight for who's the king of the trackball.

[BucklingSpring]

I just ripped one of my Optical Expert Mouse apart at the cost of damaging the rubber feet.



It is built around an Agilent A2051 Optical sensor.
See attached specs for the level of details you want to shove up your wiki.

Meanwhile, here's some of the key Features
• Precise optical navigation technology
• No mechanical moving parts
• Complete 2D motion sensor
• Serial interface and/or quadrature interface
• Smooth surface navigation
• Programmable frame speed up to 2300 frames per sec (fps)
• Accurate motion up to 14 ips
• 800 cpi resolution
• High reliability
• High speed motion detector
• No precision optical alignment
• Wave solderable
• Single 5.0 volt power supply
• Shutdown pin for USB suspend mode operation
• Power conservation mode during times of no movement
• On chip LED drive with regulated current
• Serial port registers
– Programming
– Data transfer
• 16-pin staggered dual inline package (DIP)

Do you have balls big enough to rip one of your trackball apart?

[BucklingSpring]

I move the Kensington trackball and it doesn't go very far.

I move the CST trackball and it goes a lot further.

I think it is a relevant and interesting thing to consider in Trackballs.

Now stop being a ****head.

 
Assuming your test is accurate (which I seriously doubt) and according to the 3200DPI your trackball pretend to have.
Then the EM should go 1/4th of the distance.

I showed you my chip... Now show me yours ;-)

[BucklingSpring]

That doesn't look like MY Kensington Expert.

Are you trolling me?  Notice the good old Cypress chip.  I see that USB Micontroller EVERYWHERE.  Blue Cube.  Nostromo.   I think even Leopolds - or Pokers.  Can't remember which.

Wow you are almost there don't put the cover yet... Take off the upper controller (the one with the lense) and look behind. You will see the chip.
You don't even have to pull the plugs. I did that on my poor EM without even unplugging it from my computer :-) (Shame on me)

And while I was there, I took this opportunity to Jig-A-Loo-ed the scroll wheel. I used the remaing drop in the straw to lubricate those "fking" micro balls.

I want to thank you for this opportunity... The trackball and the scroll wheel feel even better than when I got it new.

[BucklingSpring]

Oh now that IS interesting.  Hmm.... I wonder how this is working.  I'm getting like 500dpi using my technique.  Maybe the vendor fiddles with resolution?

Or the operator fiddling with the software. You're only off by 40% at relatively small distance. So I'd say not too bad for a "Ball park" guestimation.
But I wouldn't hire you to gauge the fuel I need to cross the sea.

In the end it really doesn't matter. It's the RELATIVE sensitivity that matters.  For example comparing with the Logitech M570.

 
Now you're talking - I fully agree with that.

[BucklingSpring]

So how many spins does it take for your Expert to cross your screen at 1:1 SW settings?

Same as your Expert under the exact same conditions.

Now I'm trolling.

[BucklingSpring]

I don't think you're going to do very well in your new job.

Terrible team player.

I'd report your trolling but I'm no snitch.

Thank you...

Both of us having trackballs don't make us in the same team.
I told you right from the beginning I don't believe in your protocol.

And to get the facts straight. You're right – The Kensington Exert Mouse doesn't impress by its DPI.

The real problem with it is the inertia induced by the micro balls after only few months of use. It's extremely annoying to play games with it. You want a trackball that requires a relatively constant force to move it from start to finish. That's exactly what you get with sealed bearings (like the ones on your picture). Previous generations of Expert were using those and the CH DT225 still seams to be using those as well.

[BucklingSpring]

The DPI on the CH Gen1 and Gen2 trackballs are pretty so-so.

What Gen is the current CH DT225 x7

Both the Optico-mechanical slit-wheel design (Kensington) and the Optico-mechanical perforated-wheel design (CH) have DPI limitation.

I can't remember one instance where the EM 5.0 bugged me with its 400 dpi. So as long as I can point what I want when I want, DPI is a non-issue for me.

But the size of the ball, smoothness of the motion and the buttons disposition are another story. Those factors are critical.

[BucklingSpring]

if anybody wants to help compile DPI/Sensitiivity/Whatchamacallit parameters please roll your ball following the instructions in the OP.

LoL - I hope you don't mind if I don't jump a cliff with you.
If you survive, you can call me a horrible team player as much as you want.
Then I'll remind you that I was the one calling the paramedics and saved your life :-)

[BucklingSpring]

Let me know if you find out the DPI on the CH Trackball.  I want to compare it to my measurements.

I don't have one handy and the new life you gave to my ball suckin Optical EM makes me hesitate to buy a CH just for the fun of it.

Open one of yours and tell me the numbers printed on the optical sensor chip. I'll do the research and find the specs for you :-)

[BucklingSpring]

You're about as helpful to the Geekhack Community as a blackhead on Rebecca Black.

Right - Too much is just like too little.

Forgive me for giving you more than what you asked.
Accurate information is something you are clearly not interested in.

Defrag your hard drive, shut the computer down (DO NOT HYBERNATE IT... I REPEAT DO NOT HYBERNATE), pull the plug, count to 10, re-plug and reboot.
Then try spinning the EM ball once more but in the opposite direction of your previous test.
You may find the missing 300 dpi you lost last time.

I'm done with this subject.

[BucklingSpring]

So far you told me the DPI is either 1000 or 800.  

It's kinda confusing.

 
Jeez I'm weak...

1000dpi is what an outsourced guy in India wrote me back about the EM Pro. Both you and I thought he was wrong.
But in 2003 Kensington was already using 800dpi chips. So maybe the lazy guy used your method on the EM Pro instead of retracing the real specs.

800cpi was from the specs of the sensor chip in my already few years old Optical EM (See picture above).

I don't know if Kensington would upgrade the chip for something better without issuing marketing crap. Think of Razer when they pumped the Lachesis from 4000dpi to 5600dpi... It didnt go unnoticed.

[BucklingSpring]

I get 460 dpi for the currently shipping Kensington Expert.  Same method.  Same Windows settings.

This is why the post title is what it is.

 
What makes you think two different brands of hardware would behave the same if you provide the same input from a generic device driver? Garbage in - Garbage out.

Here's a funny trackball story based on true events.

I once plug a Kensington trackball on a computer without drivers. The cursor was moving so fast, I had hard times to install the Kensington Drivers.

On another computer without drivers with another Kensington trackball. Once plug the cursor was extremely slow, I had to spin the ball over and over to get where I want.

My conclusion – You can't rely on Windows drivers to get the most from your Kensington.

Draw your own conclusion.

I'm off this thread for good. Promise!

Have fun on your Island.

[Dox]

I've just receive a Kensington Slimblade trackball and I have to admin that ripster is right. The DPI sucks :frown:. Having a 2560x1440 and 1920x1080 resolution, it takes way to much movement to move across the screen. This is my first trackball and I really like the concept but I think I will need one of those CTS LaserTRACKX to match the speed of my G700 that I usually use at around 1600DPI.

[Dox]

I put a piece of tape on the ball and it took around 1.4 revolution (+- 0.05) to cross 4480pixel. I'll let you do the calculations.
win7 x64

[Dox]

460 sound about right. It would make sense too that they use the same sensors in the expert and slimblade.

On a side note, I am a very heavy user of the middle button and scroll wheel on normal mouses. I really love the Logitech free spinning scroll wheel for that reason. After using the slimblade for a day, I think the twisting ball scroll works well for an average user but my hand get tired of twisting this ball again and again.
Now, I think the CST would really be a better option. I'm still wondering if I would be able to use the default middle button while moving the ball but I could mod something out i guess.

[Dox]

Yeah, 400 or so sounds/feels about right.

Now I have to figure out if that 300dpi for the Orbit is right.  Seems like they would all share the same sensor and microcontroller.

 I don't know anyone with an Orbit but if I come across one I will definitely try and report. Is it woody too who tested the orbit in the chart? If so, it looks like it.

[sndstrm]

Yeah, I plugged my Orbit and my G9x up to my 1920x1080 display and went back and forth using them.  It took about 5 min before I sent the Orbit to its hole without cheese.  The difference is huge even on 1920x1080 which is a fairly modest resolution compared to other larger IPS monitors.

[woody]

After using the slimblade for a day, I think the twisting ball scroll works well for an average user but my hand get tired of twisting this ball again and again.

You're doing it wrong, or I am an average user.

With the hand in usual position for trackball (point) movement, put your index or middle finger somewhere in vicinity to top of the ball (doesn't have to be very precise - I put my index quite off to the left), and try rolling the ball with your ring finger.

[woody]

@Ripster: I believe the effective Slimblade sensor is 1000 DPI, and quick test shows so.

Since it does dynamic downscaling depending on velocity, you get different movements depending on the speed of the ball. Very slow one, like the one I did before, gives about 250-300 DPI. A fast one gives about 1000 DPI. Anything in-between is meaningless. I am no robot, so can't derive the scaling details (regions/law), but most of all, I don't care - it works smooth and flawlessly.

When I am talking about DPI, I mean the events the sensor/MCU sends to PC per linear travel of the periphery of the ball, so it is also CPI. Dots, counts - all mean same to me in this context, and ball's diameter is included in the equation.

Before I was interested in the slow speed resolution, because that's what matters when pixel hunting on the screen. And 250-300DPI for a 55mm ball is very optimal. Does the CST really keep 3200 DPI at very slow speed? That'd make hitting a pixel pretty tough. As to whether 1000 DPI @55mm ball are enough for very big monitor(s) - dunno, but a quarter rotation gets me from end to end on 1600 pixels horizontal size.

Again, the warning that I assume that X-Windows is not mangling the mouse events.

EDIT: Continued after being interrupted.

[BucklingSpring]

It's built in HW acceleration.  If you go slow the test should be accurate.

I'll be updating the "All About Trackballs" wiki with acceleration technical details.

How about hardware deceleration? Did it occur to you that resolution maybe reduced below actual sensor capacity at slow speed? Then what speed will you chose for 0 acceleration (positive or negative) and can you assume this speed will be the same across sensor brands and models?

Ok I failed to shutup... Send me to jail.

[woody]

It's built in HW acceleration.  If you go slow the test should be accurate.

I bet the on the opposite - decceleration. Or downscaling at slow speeds. Otherwise at faster speeds it will be jumpy.

[Arc'xer]

Deceleration doesn't make sense or else it would be too slow and would go against the normal operation of the sensor, an acceleration limit is more logical; hell a configurable acceleration delta/deltas would be even more sublime. Acceleration is built into the trackball, it's not removalable it's pretty much permanent for the CST. It works similar to the quake engine-style acceleration using cl_mouseoffset(and accel command). In other words you can have a really low sensitivity if you move slowly but the second you flick it hard enough you can actuate the delta and move as fast as high sens.

The way mice and trackball sensors work is they automatically slow down based on the input provided and no this isn't dynamic DPI. Many people overclock their polling rate to 500hz-1000hz(if their mobo is capable of 1Khz constant) and yet when doing testing while moving at a consistent rate it equals the desired polling rate but while slowing down the polling rate can sometimes drop to even 1Hz. When you slow down the sensor samples the amount of input movements so if you ever graph the movements you'll see slow downs based on the input provided.

http://www.phoon.us/mouse/#pollingrate

Check out the polling rate section since it explains how the mouse and OS sends date. That's probably why your getting reduced samples.

[woody]

No. You're thinking as a software guy. Try again.

[woody]

Ok, have more time now.

Deceleration doesn't make sense or else it would be too slow and would go against the normal operation of the sensor, an acceleration limit is more logical

There is no limiting, and acceleration and deceleration aren't the most correct terms here. Perhaps (up/down) scaling or converting ... dunno, let the native speakers tell.

In other words you can have a really low sensitivity if you move slowly but the second you flick it hard enough you can actuate the delta and move as fast as high sens.

To do this properly, you use the sensor's native resolution at the high speeds of travel, and downscale at lower speeds. No limiting at all - simple operations with fixed point numbers.

The way mice and trackball sensors work is they automatically slow down based on the input provided and no this isn't dynamic DPI.

The sensor itself works at constant pulses per distance rate, it's the MCU that does scaling based on velocity and/or it's derivative. And yes, it's dynamic DPI.

Polling rate has nothing to do with this. Technically, you accumulate the _scaled_ impulses (== dynamic DPI), then latch/clear at some intervals and report.

[woody]

That's a different acceleration usage - the proper one. The derivative of velocity.
Hence my "scaling" attempt.

[ricercar]

Post the number of revolutions it took, your horizontal screen resolution, and your OS.

1.4, 1440, Windows7 Enterprise 32 for a Logitech Trackman Marble FX
1.1, 1440, Windows7 Enterprise 32 for an Itac Systems Mouse-trak
0.7, 1440, Windows7 Enterprise 32 for a CH Products DT225

[RPro]

The Trackman Marble FX ball is removable - it uses the ruby-like spheres which collects gunk and needs to be cleaned out (for me it's daily ewwww). I don't have a good way to measure it though. 40 mm does sounds like in the ballpark though.

[ricercar]

I don't have a caliper.

51.0 mm - FX ball.
50.0 mm - Mouse-Trak ball, appearing the same as the Mouse-trak picture.
56.5 mm - CH ball, 1/32 inch smaller than the official 2-1/4 inches diameter (supplied as a control sample for my technique).

EDIT - each (both) of my FX balls are 1 mm larger than the Mouse-Trak Ball. The difference is not due to measuring technique.

[BucklingSpring]

(...) In essense this test is better described as "default sensitivity".    Still in the end it's what get's reported to the OS that is what the user primarily sees.

Default sensitivity is what you get when you kill all the proprietary software. And yes acceleration is a *****.

The thinking process was fastidious, but I'm glad you finally came to those conclusions.
 

Maybe I should have chosen a more diplomatic thread title.

Refreshing. Then maybe I would have played along instead of against.

[ironman31]

Microsoft Cordless Optical Trackman
Ball size: 45mm
Horizontal resolution: 1680
Number of turns: ~1.75

Though, I definitely can't track with any relative speed. The tracking mechanism sucks.

[redpill]

Still, from these preliminary numbers I'm not seeing why the MTOs and MTEs sell for $200 plus on Ebay.

Because there is more to trackballs than just DPI

[ironman31]

Because there is more to trackballs than just DPI

Well if dpi is the only problem with my trackman, the dpi has a major influence. This thing is completely unusable

[redpill]

Need mto numbahs!!!!

Can't help you there, me no likely thumb balls

Well if dpi is the only problem with my trackman, the dpi has a major influence. This thing is completely unusable

Well after seeing the comments by British on the CST L-Trac thread about still experiencing some imprecision despite the high DPI, I'm not sure what to think honestly.

http://geekhack.org/showthread.php?5625-CST-L-Trac-laser-trackball/page22

[daerid]

Just kinda wanted to throw that in there

[Input Nirvana]

Show Image

Just kinda wanted to throw that in there

...num num num num...

[Surnia]

Hai, please don't rip me to shreds, First post here.

I have the orbit with scroll ring, and the cheapo DX caliper we have measures it at 40.4mm diameter. I find the dpi quite comfortable on my screens (2048 pixels wide), but I'll run measurements on it later.

However, if you use sndstrm's numbers, it puts the DPI at 384.

[Surnia]

Well I was going with sndstrm's 1920. I'll run the measurements now... gimmie a bit xD

*edit*

between 1.25 to 1.33 revolutions to go across 2048 at 6/11 on the mouse settings.

In terms of perceived comfort, on par with my CM Sentinel (did NOT buy it for the colourful lights and whatnot, I just wanted DPI adjustment and it was the cheapest option...) at 1800dpi, if not ever so slightly slower.

To be honest I like it where it is, good enough for general use while I can bring the Sentinel down to 450dpi for really precise work.

[Surnia]

Another rather small observation as well, I'm not sure the orbit has acceleration... or if it does it kicks in at very high speeds (high enough that its almost at the level where it characteristically skips). I tried moving it slowly vs. flicking the ball with a finger on it, I get the same amount of screen travel. Any better ways of testing this?

[Over_Kill]

Hi all,

I came across this thread because I was looking for some trackball information for my MSO which I purchased new many years ago and love to death.

I just wanted to point out a couple of things - The diameter of the ball is 1.496" (which is appx 38mm. or 37.9984mm to be exact). I also have another piece of information that I see people looking for online quite often and I finally decided to get it. The ball bearings in the MSO are 2MM. Mine had a flat worn into them so I had to rotate them. The ball was actually rubbing on the red plastic housing where the LED is for the sensor. It looks like you already have the DPI for this mouse so I won't do that but I just wanted to give the other information so it could be used by someone.

[Over_Kill]

Yes I have that one. OK I will try and run the numbers today or tomorrow.

[Over_Kill]

Good morning ripster,

Dotted my ball this morning and it took 1.5 turns from one side of the screen to the other at 1680 x 1050.

If you need anything else let me know.