Instinct 2 Solar pulseoxymeter gives false readings.

Mine shows even lower readings than yours. 88-92% most of the time even though I keep still and the watch tight at heart level.

3286652 said:

Therefore I would suggest Garmin to stop advertising this function and remove it from firmware.

I own both, an Instinct 2, and a fingertip pulse oximeter, and they both give consistently practically identical values, so I am quite thankful the watch has the sensor, and would not like that Garmin removes it from the firmware.

On the other hand, you are not alone complaining about low SpO₂ values from Instinct 2. It likely depends a lot on the physiology of the concerned person (I have well pronounced and visible veins), and on the fit and position of the watch. Also, the PulseOx sensor needs that you stay still during the measurement, so it is unlikely to work during climbing.

Physiology is important. My physiology (running ½ marathons and climbing) is evidently not good enough for Instinct to show the real thing. BTW veins have nothing to do with SpO2 measurement. You are just lucky to get working sensor..    

3286652 said:

BTW veins have nothing to do with SpO2 measurement

They do, since the SpO₂ sensor measures the saturation by analyzing the light reflected by the subcutaneous tissue and bones through the blood in the veins and capillaries. The closer, and the better visible the veins are, the better for the analysis. At a fingertip sensor it works in a different way - the light goes through the finger from one side to the other one. 

I have very very visible bulging veins all over my body especially on my arms.. Under the sensor there is a cluster of them, scary thick. Still the sensor reads very low o2 everytime. Maybe there should be a calibration option for differences in veins visibility via sensor.

It is not only the veins self, but also the epidermis, the skin tan, the subcutaneous fat and tissue, the bones, and also the hemoglobin level. I agree there should be a calibration option, but luckily for me, I do not need it at all.

how is it that every garmin you have works perfect, can you tell us where you buy your garmins so we can have perfect devices too :)

would be really nice if you could post a picture of your fingerprint spo2 and your watch when they show same value

Bullet said:

how is it that every garmin you have works perfect, can you tell us where you buy your garmins so we can have perfect devices too :)

I do not think I have a better watch than enyone else, or that there is any difference in the individual watches. I think I am just lucky that my physiology matches well the physiology of the test persons who participated in the development and testing of the device, hence I am having the expected results.

Bullet said:

would be really nice if you could post a picture of your fingerprint spo2 and your watch when they show same value

I do not have the fingertip oximeter with me right now, but you can have a look at the values - both historical, and taken right now. I think the values are clearly as expected, even without seing the fingertip oximeter data. During the day, mostly 98% to 100% (except of during apnea training, where it can go much lower). During the night the values may get a little bit lower, since I wear the wristband rather loose during the sleep, and also tend to sleep on my arm, reducing the blood flow. Still the data looks rather credible to me.

Works for me too generally. 

Yes of course it does