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Hello Alex,

This is not a bug of the model:
* The 255 value is the max minutes that can be stored on a single byte. When you have longer stops, OSTC just use several one, at the same depth.
* At 6m with a 18/45 mix you don't have a big enough gradient of partial pressure, hence you will desaturate verry sloooowwwly. And because you have also a slight altitude (or bad weather), the surface presure seems to be ~ 981 mbar, which make things worst...

To make it clear, look at the profile (computed with the OSTC decoplaner), with various last stops.

[EDIT] Ok, here is the plot:
[img]http://www.heinrichsweikamp.com/file.ph ... _6..3m.png[/img]

[quote="Alex"]
Does anybody test 1.90 in real in Trimix dive?
[/quote]
Do you really dive trimix with no deco mix ???
Be more realistic with you plan.

Hi,
original plan is with use of 50/15 and O2.
I forgot to activate them.

But if I plan the same dive with VPlanner(+2).
I have a calculation of:
Run 141 min

.
.
.
18m-3
15m-5
12m-7
9m-11
6m-84

the different is defenetly to big

Alex, you are comparing two different algorithms!
Running your dive plan with MV-Plan (20m/mn descent and 10m/mn ascent) gives this timing:

DECO: 18m for 03:00
DECO: 15m for 03:00
DECO: 12m for 06:00
DECO: 9m for 09:00
DECO: 6m for 107:00

Same gas, same time, same GF.

Simulation on my 1.90 MK2 gives the same result as Alex so there is a bug.

@Stephane and Alex:

In this situation (no deco and 6m last stop), you de-saturate so slowly that the mathematical model is quiet unstable. Try to change the surface pressure a bit, varying from 1030 mbar to 980 mbar, and you will have dramatically different times at 6m.

@ Stephane
sure two differnet models but if I compare your Deco @6m 107 min
My Deco with vplanner @6 84min.
There is a different, sure! but acceptable.

But 6x 255min?

Now I will play with the suface preassure
Calculation with deco Gases are OK

Cheers
Alex

I just update to 1.90 and I read your discution.

I made simulation with MVplan. I was not able to get it with your plan but for tX 10/52 15' at 50m with gf 30/85 ... I get a 3953' stop at 6m ...

I have alos some trouble with jdivelog to save setting to the ostc since 1.9.

I have just upgrade my computer to version 1.90.

There seems to be a problem with the Gas Setup, when I set a gas to first gas the value for meters is set to 0 for that gas?

If I setup the gas as not first gas, it is okay to put in a meter value, when I change the gas to First gas that value is resetted.

Since version 1.80 there is not possible to reset the stopwatch during the dive? is there a reason for that? I see no reason to have two clocks showing the same thing (divetime and stopwatch)...

Kent, the first gas defaults to zero as you are breathing this from the surface. You won't be switching to your first gas at depth unless you're free diving first.

But it is still strange for me, should I reprogram my Gas list every time after I have change the First Gas sinse the value is resetted?

If I put in AIR 21 in 57m then I will have 1.4bar, this value is resetted when I put this gas as first gas, why this change in this release?


Regthing Wrote:
-------------------------------------------------------
> Kent, the first gas defaults to zero as you are
> breathing this from the surface. You won't be
> switching to your first gas at depth unless you're
> free diving first.

Kent Persson Wrote:
> There seems to be a problem with the Gas Setup,
> when I set a gas to first gas the value for meters
> is set to 0 for that gas?

The first gas is the gas you start on the surface (=0m) with. The change depths are to be configured for the ascent only.

> Since version 1.80 there is not possible to reset
> the stopwatch during the dive? is there a reason
> for that?

You still can reset the stopwatch, of course. Choose Menu -> ResetAvr or the quick reset "Left Button -> Left Button -> Right Button".

regards,
Matthias

> The first gas is the gas you start on the surface
> (=0m) with. The change depths are to be configured
> for the ascent only.

Then I need to reprogram the gaslist everytime I use a gas as first gas?

If I want to do a dive with only one gas, O2=50% and want to set the ppO2 to 1.55 so it fits 21m instead of 22m, how do I do that, this is new in version 1.90

> You still can reset the stopwatch, of course.
> Choose Menu -> ResetAvr or the quick reset "Left
> Button -> Left Button -> Right Button".

Thanks, I found that now

Hi,

You can set the change depth for deco gases where ever you want to. The ppO2 is for your information only and it can't be set.

A dive with one gas only requires this gas to be "First Gas" and the first gas always starts at 0m. All other gases should be either "inactive" or have a change depth of 0m so they aren't taken into account for the decompression.

Regards,
Matthias

How do I change the Custom text (up to 23 characters) in the main screen?

Use Jdivelog
Load parameters from Ostc
Change owner on Jdivelog
Save parameters to Ostc
It's done

Kent Persson Wrote:
-------------------------------------------------------
> How do I change the Custom text (up to 23
> characters) in the main screen?


You need one of the after market log book software options. Divinglog 5.0 or JDivelog. I couldn't get JDivelog to work.

I have jDivelog, I can import my dives an so on, but where do I put in my own text in that program?, I like to put in my phonenumber in the main screen.

> > How do I change the Custom text (up to 23
> > characters) in the main screen?
>
>
> You need one of the after market log book software
> options. Divinglog 5.0 or JDivelog. I couldn't get
> JDivelog to work.

Icon "Divecomputer" then "OSTC Settings" and you'll find out the trick by yourself.

I use Divinglog - it's worth the small extra fee.

Is it by design or a bug; When I have the MKII in gauge mode, the device is not showing acent/decent rate if I go to quick?

It is not showing surface time as well, it is showing 0:0

How is it with deept calibration, me and my friend both have the MKII, they are differ more than 1 meter at 21m, and also around 6 meter.

We will dive today, I will compare with my old computer.

/ Kent

Kent,

You need to spend some time understanding how each of the CF's affect the computer:

Take a look in here especially CF05, CF20, CF30

http://www.heinrichsweikamp.net/en/ostc ... _functions


The depth sensor has been discussed to death. Search the forums. Search wikipedia for buoyancy and salinity. The more salinity in the water the more buoyant you become. (a bad explanation) is that, at say 6m there is less pressure above you than on 6m of fresh water. Therefore NO computer is accurate in measuring the depth (unless the water happened to be at a specific temperature and salinity and the weather outside was exactly at 1 ATM which never is).

THE OSTC lets you calibrate a better approximation for your comfort. However don't worry ALL calculations are done based on pressure so you can't go wrong.

For apnea I would set the salinity to 1.00 regardless of the actual salinity as it will give you an extra buffer (even if it is only mental).

D

Kent Persson Wrote:
-------------------------------------------------------
> Is it by design or a bug; When I have the MKII in
> gauge mode, the device is not showing acent/decent
> rate if I go to quick?
>
> It is not showing surface time as well, it is
> showing 0:0
>
> How is it with deept calibration, me and my friend
> both have the MKII, they are differ more than 1
> meter at 21m, and also around 6 meter.
>
> We will dive today, I will compare with my old
> computer.
>
> / Kent

Hi thanks for your answers, I agree about the calculation, but it is not good if it is so big different in deepth between two equal MKII computers, I'm doing deco dives and we do stop on 24, 21, 18, 15, 12, 9, 6... it can´t differ over one meter with my buddys.

It seems to be something wrong with mine device, we put mine and another MKII computers on a rock today, the other device was steady on the deept, mine was changing all the time, it change from 17.x to 22.x meter when it layed still on the bottom.

I have taken photos on it, can I send them to Matthias@heinrichsweikamp.net
Maybee we have a video on it as well.

Back to my other question, I'm not talking about apnoea, I'm talking about gauge mode, when I put my MKII in gauge mode, it will not show acent/decent rate or how long time we have been on the surface between two dives.

When I have in computermode OC with gradient factor, it shown very nice, so my question is: why not in gauge mode?

CF05: is on default value = 7
CF20: is on default value = 10
CF30: is on default value = 0:10

Best regards
Kent Persson

Kent Persson Wrote:
> we put mine and another MKII computers on a rock
> today, the other device was steady on the deept,
> mine was changing all the time, it change from
> 17.x to 22.x meter when it layed still on the
> bottom.

Much tide? Seriously, you should get a steady reading, of course. We should have a look at this unit: Please mail to info@heinrichsweikamp.com

Ascend/Descent rate in Gauge mode has been added - This will work in 1.91 and later. Since there is no tissue load in gauge mode no surface interval timer is displayed.

Regards,
Matthias

Good to hear that this function is added in version 1.91.

Even if it is no tissue load calculated it could be nice to have surface time, when we dive after a plan we still need to know how long surface time we have before we enter again, can you add it? – I think there is more people who like this.

ENDLICH ))

Vielen Dank für die Dil-PO2 Anzeige im CC Modus!!!
Was lange währt, das währt am Besten

Many thanks for the Dil-PO2 display option in CC Mode!
Now we can flush the loop as hell without calculating

Cheers,
Frank