New to Skytrak. +1 index but average carry is 20 yards short. Help!

[p1n1983]

Hi all! I purchased the Skytrak a month ago and finally it arrived to my home yesterday (I'm from Argentina).
In this waiting period I read everything I could about setup and best practices to get the most of out it and get it to be ass accurate as possible.
I tested it in 3 different sessions of 10 balls each (one was 9 balls actually).
1st set was with an 8 iron from the math. The results in generall were as I spected for my natual fade, but when I looked at ball speed and carry distance they were too low. I normally carry my 8 iron around 148 yards in 20°C at sea level, but the Skytrak told me that the average was 127. That's more than a 10% error.

Here is the data of that session:

I also performed another set of 10 balls with a very small tee to avoid turf interaction but the results were almost the same.
I performed another set of 10 balls from the turf but this time with a 5 Iron, all the data was OK except again for ball data and carry distance. I average around 172 with a 5 iron but Skytrak told me I was around 150-155 (I´m not at home rigth now so I don't have the data). That's another 20 yards short.

Checks and test I made that I can remember:
- Unit placed at same height than turf but not placed on the turf to avoid vibration.
- Remove the camera film.
- Make sure to have the unit without any tilt.
- Align the unit to my target, results confirmed that is was placed directionally ok.
- Did the session with a Pro-V1, same ball that I play.
- Placed the ball in the red dot, with the logo facing the cameras in every shot. Also tested to place the ball a little forward and behind the dot. Same results.
- Placed the unit above and below the hitting math, this lead to misreads and no reads.
- Because I have white walls behind the balls flight, I covered them with black stuff.
- Session conditions were the ones at default, 500 altitude, 21°, 50% humidity, no wind. I set the altitude to 10000 and of course the carry increased.
- Made some shots really fast, out of my shoes but only gained a couple of yards in the process. Definitively not Indoor Swing Syndrome.

Maybe I remember more stuff I tried, but if you can help with more ides or suggestions on why the carry is so off I'm all ears. I'm hopping this is a setup problem rather than a Unit issue, if that is the case shipping it back to the US and back home is going to take a couple of months.

I know that I can solve it by just adjusting the altitude (I'm satisfied with the other numbers), but as I told before, I'm from Argentina and our currency is pretty weak and I just can't afford the 100 UDS subscription, it's a lot more expensive for me than it is for a person that lives in the US or earn money in UDS, EUR, etc.. Once the 1st month trial is over I wouldn't be able to adjust it anymore.

Thoughts, ideas?

Thanks in advance.
Marcos

[chicub15]

https://gunghogolf.com/articles/indoor-swing-syndrome-skytrak

[Morini]

Remove camera film? The thicker film should stay on.

So the tee test showed no difference? That theoretically rules out club mat interaction. Your spin is quite high for that ball speed. I'd test a bit more.
Tilt, level, white wall, etc etc etc will have zero bearing on ball speed, spin etc.
Altitude is quite marginal, and not the issue. It is something like 1.2% extra carry per 1000 feet. Humidity? Negligible.

That ball speed is indeed quite low if you expect to carry 148 yards. And ball speed on Skytrak is generally accurate as it is one the unit's strengths. Not much can go wrong when analyzing photos to see how far the centroid of a circular shape moved in 4.12 milliseconds. It will get it to a pixel or so, and will not be off much more than 1 mph on average.

If it is not the mat, it is very likely one of these:

• Indoor swing. Not sure why discount that. It is very very common.
• Cracked ball. Try a new one if you haven't.
• Bad contact. Use foot spray to make sure.
• The only other option is mis-calibrated skytrak, and that is very very uncommon.

[p1n1983]

Here is an update after a couple of day of testing. The unit is just fine, the tests I run were incorrect.

1st mistake I made was to swing barefoot instead of with my golf shoes. With shoes my speed increased a bit. Maybe 4..5 yards.
2nd mistake was to focus a lot in ball direction and not completing the swing. Gained around 6..7 yards there. This also happens on the course when a shot is hard and didn't know this was taking a few yards away from my shots.
3rd Tested the unit without my on course clubs, but with 20 year old clubs that I only use to practice at the range. This clubs have weaker lofts and are less "Improvement Irons" than my current on course set, googled a little bit about it and with today 8 Iron you can hit around 10 to 20 more yards than you hit with and old 8 iron.
For the test I used a 7 iron that have the same loft as my current 8 iron, specting to behave the same way but that is not just the case. Old irons launch lower and with more spin, hurting distance.
4th Also worked a little bit on the weekend at my course and in average I was hitting it 5 yards shorter than spected because of swing changes in the last few months, more accurate but less carry.

Conclusions: Nothing to worry about, the unit is just fine and I'm really enjoying it.
Have to focus on completing the swing, no matter what.
I hit it 5 yards less now in average.
Not only old clubs hit it shorter because of soft loft, but also because they spin more and have a lower launch.

My clubs sleep at my club all week but I will bring a few home in a couple of weeks to test them and confirm all of this assumptions.