Instinct 2 solar charging - how many % battery level increase?

@Yeti,

I did this test before upgrading the widgets:

Test done : 1520-1620 27/02
Initial battery level : 64% (65% after 60min)
Solar intensity : about 60 (range decreasing from 80 to 50, with about 60% average)

Time: Battery change:
15 min +0.32%
30 min +0.80%
45 min +0.95%
60 min +1.11%
75 min +0.95%
90 min +0.80%
105 min +0.64%
120 min +0.48%
3 hours +0.00%

How come the battery after 60min (the time I tested) went down? (I didn't do any activity or do any specific thing (just watch)...)

Other tests that I had done so far, the level after the test interval is about the same, not decreasing significantly like this one!

Thank you very much!

Thank you for your comments.

1. About the light distorting effect of water, it should be 0 since the watch face is at the water level (not under the water).

2. You seems to imply something like the solar intensity display 100% for a certain lux and if we get more than this, it still display 100%.

Thus my 100% level may actually 100lux but Yeti's 100% may be 200lux...

This can explain the different increase in battery level.

3. However, there is nothing on formal Garmin document that I found that say anything about this.

So I can only assume that 100% here is the maximum lux that the watch can receive and thus all watch 100% level is the same amount of lux...

Thank you very much!

To me it looks like the charge from solar is not as "sustainable" (probably not the right word) as charge from the charger. I've seen it myself and also read reports from others.

I think the charging level that is reported from solar is not realistic. This is one of the mysteries with the battery charge on the Instinct Solar 2 watch (and maybe other watches).

But also the charging level when charging with a charger is not realistic. It "jumps" after you disconnect the charger, but looses the fist part of the charge quicker than later.

If the watch checks the battery level just by measuring the voltage of the battery, that would explain the overestimated charge from solar and maybe the non-linear discharge, but not the "jump" after disconnecting the charger.

But this is just wild guessing, I don't think Garmin will tell us and the only thing the Guesstimate app can do is read/show the data provided by Garmin

Error -2 means "We timed out waiting for a response from the host. "

So maybe the server name is wrong or the watch is not online

Somewhere I did read that 100% is not the max what the solar panels can take in, what would explain some things, but why would someone then call it 100%?

Maybe marketing and the 100% refer to the 50k lux.

I have a lux meter somewhere, I could in theory make some measurements

Yeti said:

Somewhere I did read that 100% is not the max what the solar panels can take in, what would explain some things, but why would someone then call it 100%?

The primary source for this is DC Rainmaker, whose claims like this I would be VERY careful about believing.  He claimed  that if the sun is over 50,000 lux, the solar panels can "leverage" this (he loves inventing buzzwords).  The fact is solar panels can not do this infinitely and the downstream hardware may not be able to handle the output and they will all have protection mechanisms in place.  What the max is, I don't know, 50k was never stated to be the max, but kind of an average value to probably even out between light and dark periods over a three-hour timeframe, but I can't see much over 100k being possible.

Just had a very quick check. It's hard to find stable readings with the sun though

When my lux meter measures around 10000lux the watch shows 23-24% solar 

19000lux shows 51-52%

Around 30000lux is already 100%

Please keep in mind that I've just done a very hacky setup, angles of the watch and the meeter might not be exactly the same and also I have no way to verify that the meeter is doing it's thing correctly

I think this means comparing panels based only on the charge/percentage/time measurements is very likely pointless...

If it is true, the only meaningful way I can imagine is using identical lamps to test

(Or maybe at same 0<x<100 percent solar intensity and same battery charge values, but that's very hard to achieve with sun only)

1. I once tried to charge from a downlight (I tried solar charge but not enough, so the batt ran out and the watch power itself off) for about 10 hours, but looks like very minimal battery level gained since after that I tried to power it on, but it turned off immediately!

2. I notice that while I am indoor, solar intensity is almost always 0.

Unless I am outdoor in the sun, the solar intensity is usually 0 in my case.