Cons of Colour Screen Dive Computers?

[Blasto]

Are people such tight-wades that they need to worry about the cost of batteries over the functionality of a high grade color screen computer?

It's not the cost, it's the availability. A single battery swap on a watch or puck style computer costs more than a couple years' worth of AA cells, not to mention rechargeables. OTOH, you don't have to worry if you've charged the batteries, since they last so long.

It's a bit of a difficult question to answer, like "what are the cons of quartz watches". Uh... they're better? You have to grasp at straws to answer it, such as "you won't feel as attached to horology culture".

Same with color screen computers, they're better, unless you really have to find something they're not better at.

 

[dmaziuk]

It's not the cost, it's the availability. A single battery swap on a watch or puck style computer costs more than a couple years' worth of AA cells, not to mention rechargeables. OTOH, you don't have to worry if you've charged the batteries, since they last so long.

I assume you're talking the ones without user-replaceable battery? On my puck that wouldn't add up even if you stacked the OEM "battery kit" (those tend to come with 100000% mark-up) against a cheapest liquidation bulk pack of AAs from a dollar store.

(And besides a good fresh CR2340 lasts 2 years in it, so couple of years worth of AAs is merely par for the course.)

 

[Oldbear]

I allowed myself to suffer from "Dive Computer Malfunctioning" due to my negligence to put a fresh set of batteries in my dive computer and transmitter before remote dives. I got hosed once and almost another time until a local Thai found my battery size literal minutes before we set sail.

In today's market I would not even consider a dive computer that did not have User Replaceable Batteries. Nor do I sell them in my store. There are just to many good dive computers these days that the user can change the batteries themselves...and these are common battery sizes, like CR2340, CR2450 or AA.

I guess if you got an old computer/transmitter that you have to send it back to the manufacture or authorized service center...suck it up Cowboy.

 

[Hatul]

That is incorrect about rechargeable batteries. The Shearwater Perdix has a color screen and takes AA batteries.

He’s right though that the color display uses much more power and uses either a rechargeable battery or removable battery that needs changing every few dives, nothing like the once a year or two battery change of the black/white LCD screen.

 

[RonR]

Having developed for both types of screens, I can say that emissive color screens are typically far easier to read in almost all conditions- where they fall short is in very bright sunlight, when the ambient light can overpower the screen. So your diving environment might influence which is best. Color screens are also typically higher resolution and much higher contrast, both of which improve legibility.

The comments about the need for more battery to support color screens are spot on- with the Cobalt 50% of the power is used by the display, more if brightness is turned way up. More pixels require more power. That means a battery- either disposable or rechargeable- that can deliver much more current than coin cells.

One thing to look for with color computers is how much dive time they deliver before needing to charge or replace the battery. We get about 40-50 hours of actual diving per charge on average, depending on screen brightness, and 6-8 months of standby. The goal was to be able to reasonably be able to do a week long liveaboard trip without needing to recharge. I know Shearwater and Suunto both have excellent efficiency.

The rechargeable vs. disposable battery question comes down to a personal preference and comfort level. I can say that in eight years of production the percentage of our rechargeable batteries that have required replacement is very small. And the Li-ion failure mode is typically a gradual loss of capacity requiring more frequent recharging, not suddenly having no power at all. Li-ion batteries are quite reliable, and you don’t ever need to open the computer. On the other hand, there is a lot of appeal to a widely available standard disposable battery, and you then don’t need to carry a charger- though USB charging is now so ubiquitous most of us are never far from one.

It's not just user replaceable vs. off the shelf disposable, there is a continuum of battery solutions:

• Not replaceable- battery dead= computer dead.
• Not user replaceable- requires sending to factory. Depending on cost, may effectively be dead.
• User replaceable but not a standard battery you can buy locally. (FWIW, that's where we are with Cobalt.)
• User replaceable with an off-the-shelf battery, but fiddly to do, with a risk of flooding if you don't get it right.
• User replaceable with a readily available consumer battery and a dead simple and reliable sealing system. (Shearwater, for instance)

And with nuances in between. Of course, with the first three above, if the battery lasts 10+ years there may be no effective difference between them.

User interface is the major determining issue for me- can you use it without a manual?

-Ron

 

[Diver0001]

So I'm going to pull the trigger on a dive computer and have narrowed down my choices to either the Suunto Eon Core or the Mares Matrix. I like the Eon Core's simple and configurable screen layout. I like the functionality and screen layout of the Matrix (one of the few smaller dive computers that has a compass). Both computers have rechargeable batteries that you can charge without having to expose the insides. However, my query has to do with colour screens, are they that useful? Any disadvantages or peeves that users of colour screen dive computers have noticed?

I'm a recreational diver, been diving a few times a month recently. I don't think I'll ever go into technical diving. I do enjoy the occasional night dive. Budget is not a problem although who wouldn't want to save on a few hundred bucks.

I'm severely colour blind and I have trouble with red on a black background. Other than that, if you're not colour blind then I don't see any reason why a colour screen would have any disadvantages.

R..

 

[RonR]

I'm severely colour blind and I have trouble with red on a black background. Other than that, if you're not colour blind then I don't see any reason why a colour screen would have any disadvantages.

R..

That's an excellent point- with the most common form of color blindness red on black is nearly invisible. It's why we don't use red at all, but a color with a large component of yellow that still looks reddish to non colorblind people but provides a distinct difference in luminance. There are simulators that designers can use to evaluate legibility for many forms of color blindness. Differences in color perception are very common. Looking at actual screens, not just pictures or representations, is the only way to evaluate legibility.

-Ron

 

[Diver0001]

That's an excellent point- with the most common form of color blindness red on black is nearly invisible. It's why we don't use red at all, but a color with a large component of yellow that still looks reddish to non colorblind people but provides a distinct difference in luminance. ... snip....

-Ron

You mean orange ....

Orange is *definitely* better than red on a dark background. In my case, however, I cannot distinguish orange from brown or green most of the time. On the same token, I absolutely cannot distinguish red from green or brown either .... so orange is an improvement but by a small margin. If the screen makes use of green to mean "ok" and orange as a substitute for red to mean "not ok" then I would probably not be able to distinguish that any better than if the information were red.

This red-on-black thing can become very annoying. For example, traffic lights that are red look to me in certain light conditions like they are turned off entirely. I've been known to stop at lights that were *actually* turned off because I thought they must be red..... That is how severe it can be.

On a dive computer it can be more than annoying. A couple of years ago I borrowed a Shearwater computer from a buddy of mine to try because I was thinking about buying one. Of course I didn't test-drive it at slow speeds. My first dive with the computer was a trimix dive. Nice and deep and nice and long..... I didn't think about the colour scheme until during the dive I passed above the depth for a decompression stop (by a few cm) and some information on the screen turned red and started to flash. To me it looked EXACTLY like the information that was most relevant at that particular moment just disappeared from the screen. I thought the computer had malfunctioned so I showed it to my buddy who had me descend by 1/2 meter and then the information reappeared.

I complained about that on the internet and much to my embarrassment someone from Shearwater responded. As it turns out Shearwater computers have a specific mode for colour blind users that I wasn't aware of. It makes a HUGE difference to the readability of the screen. If you are coulour blind then this is definitely something you want to pay attention to before you buy a computer with a colour screen.

R..

 

[DaddyJr]

Hello everyone, thanks for all the comments. In the end I went for the colour screen option, so I just purchased the Suunto Eon Core. Perhaps due to a Canon camera of mine being destroyed by water seeping in, this played heavily on my mind against dive computers which allow occasional exposure when you change the batteries.

All that's left for me is to take the unit for a dive!

 

[Freewillow]

As said earier, and correctly , the battery runs out quite fast. So you need to keep your battery level, in oder to get a ful dive............