I just found that the average depth reported for a dive in the list of all dives, and the one on the general tab of the info box, differ from the one reported under the gases tab on the info for that dive.
For example on my dive #10, the first reports 26.69 and the second reports 26.30. Usually the second is slightly less than the first, but at least once it was higher. Am I missing something, or is this some programming error?
average depth different
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nick
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Re: average depth different
You are missing something.
The average depth is calculated differently in the gas panel, it is based on the actual samples used for the duration of a particular tank, and is used for calculating other data. The overall average depth is reported based on what the dive comptuer recorded (in the cases it is available).
Thank you.
The average depth is calculated differently in the gas panel, it is based on the actual samples used for the duration of a particular tank, and is used for calculating other data. The overall average depth is reported based on what the dive comptuer recorded (in the cases it is available).
Thank you.
Re: average depth different
Apparently I am missing something. Could you go into a little more detail, please. It sounds like you're saying not to worry about the difference, but enquiring minds want to know. All the information is coming from what the Zoop recorded, so how can there be different average depths?
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nick
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Re: average depth different
Your computer records in, say, 20 second intervals.
What happens when your max depth is between samples? That's right, the computer records a deeper max depth than is available in the samples. Same principle.
And as for *why*, as above, when you are using multiple tanks MacDive needs to calculate the average depth of the samples used for that particular tank. I am aware it may be slightly off, but I never considered it to be a big deal. Really that value is only used for internal calculations and was added on the gas tab for debugging, and I left it there.
It isn't even used in the case of one tank, MacDive uses the overall average depth as per the dive itself as it is much less overhead to calculate. So, in terms of worrying about it, you are looking at an internal value that for a single tank dive is of no consequence.
If you are using multiple tanks, then it becomes relevant, and is based on the specific depth samples that matter.
What happens when your max depth is between samples? That's right, the computer records a deeper max depth than is available in the samples. Same principle.
And as for *why*, as above, when you are using multiple tanks MacDive needs to calculate the average depth of the samples used for that particular tank. I am aware it may be slightly off, but I never considered it to be a big deal. Really that value is only used for internal calculations and was added on the gas tab for debugging, and I left it there.
It isn't even used in the case of one tank, MacDive uses the overall average depth as per the dive itself as it is much less overhead to calculate. So, in terms of worrying about it, you are looking at an internal value that for a single tank dive is of no consequence.
If you are using multiple tanks, then it becomes relevant, and is based on the specific depth samples that matter.
Re: average depth different
Thanks, I appreciate the explanation...