Local Rule G-5, Prohibiting Use of Distance-Measuring Devices

[Mr. Bean]

10 hours ago, rogolf said:

A little research in past Rules editions says they are "traditionally accepted".

 

I sure know that, but my question was to 2bGood as a comment to his post saying 'You do measure distance with a maps and charts '.

[Mr. Bean]

9 hours ago, antip said:

For people practised in this skill, it was accurate. And golf rules banned it.

https://www.osc.co.uk/tools/range-estimation-using-range-stick/

 

D14-3/2, as I understand it, forbids use of sticks, cards or similar having marks on it. It does not say you cannot have five pencils of different size for that purpose.

[Mr. Bean]

10 hours ago, Slagathor said:

No comment on legality, but for accuracy:

 

With a couple of Google searches, it looks like an optical rangefinder's practical accuracy clocks in at about 3.7%.  This is based on field testing performed by the USFS on various rangefinders, and is for a handheld model - no tripod, etc.  So for practical use, that would equate to a potential error of about 7.5 yards at 200 yards out.

 

 

 

Many years ago I purchased one of those optical range finders and threw it in the trash the next day. At least that particular device needed the height of the pin in order to give any reading. Not very handy as the height of the pin may vary even on the same course from hole to hole not to mention between courses. Also it may happen that you do not see the entire pin from your location which again renders the optical device useless.

 

Maybe there are better devices available today but I do doubt it as laser finders are so common nowadays and allowed more or less everywhere except the high level pro tours.

[antip]

2 hours ago, Mr. Bean said:

 

D14-3/2, as I understand it, forbids use of sticks, cards or similar having marks on it. It does not say you cannot have five pencils of different size for that purpose.

Nice try, but pre-2019 you would be pinged under  old 1.4 if you start pulling out your pencil set and measuring up your distance with them. From 2019, not so sure, probably need to send it in to the folk paid the big bucks to see if anything has changed.

[antip]

13 hours ago, Slagathor said:

No comment on legality, but for accuracy:

 

With a couple of Google searches, it looks like an optical rangefinder's practical accuracy clocks in at about 3.7%.  This is based on field testing performed by the USFS on various rangefinders, and is for a handheld model - no tripod, etc.  So for practical use, that would equate to a potential error of about 7.5 yards at 200 yards out.

 

Based on reviewing various golf rangefinder tests and the USFS laser tests, the results vary quite a bit.  Laser rangefinders are quite accurate if there is a reflective target used.  However, assuming we are talking tournament play without a reflective device on the flagstick the results vary from about 1.5% to 4%.  Based on reading a couple if actual tests of golf rangefinders, it looks like those tests show a practical accuracy of 2% non-slope corrected.  The golf tests did not indicate, however, if there was a reflector/prism on the stick when testing.  So, assuming the 2% number is in the ballpark, that would give a practical accuracy of around 4 yards of error at 200 yards.

 

I'm unclear how this would compare with estimating distance to the pin with a pro yardage book, as I have no real experience there.

Despite these stats on accuracy saying up to 4% variation, my experience on my home course is my Bushnell produces precisely the same answer measuring the distance to the flagstick on the par 3s when I measure them on consecutive days with the flag in the same position. 

[Mr. Bean]

5 hours ago, antip said:

Nice try, but pre-2019 you would be pinged under  old 1.4 if you start pulling out your pencil set and measuring up your distance with them. From 2019, not so sure, probably need to send it in to the folk paid the big bucks to see if anything has changed.

 

Maybe so, but if that was not allowed why the Dec does not say it? Why it is/was allowed to have one item with known measures but not two or more?

 

One of those Decisions that gives an answer to one question when it should give an answer to all the questions...

[Slagathor]

For those asking about accuracy follow up:  USFS study was USFS Study

 

I looked at the laser rangefinders that did not require a reflector to grab a range of tested accuracy.  For the golf rangefinder, I can't find the link - it was buried about 8 pages deep in a Google search to find someone that actually tested instead of just regurgitating mfr specs.  But the golf rangefinder was tested at 50 and 100 yards and gave gross error of 1 & 2 yards compared to a measuring tape.  My assumption is that if you have a recent laser unit + prism/reflector on the stick, the accuracy may be better.  My stated assumption was that the stick would not have a measuring aid equipped for this discussion.

 

And for Mr. Bean - the unit that the USFS used was a stereoscopic unit with a baseline of ~18 inches or so.  So much different than the typical stuff we would use.  But if you wanted to push the rules...  And based on 15 years of shooting with rangefinder equipped film cameras, my assumption is that technique & proficiency with an optical rangefinder would allow you to bracket the distance by focusing from near-to-far and comparing to a far-to-near focusing technique.

[rogolf]

1 hour ago, Mr. Bean said:

 

Maybe so, but if that was not allowed why the Dec does not say it? Why it is/was allowed to have one item with known measures but not two or more?

 

One of those Decisions that gives an answer to one question when it should give an answer to all the questions...

And here I thought that Decisions had disappeared as of January 1, 2019?🙃

[Mr. Bean]

3 minutes ago, rogolf said:

And here I thought that Decisions had disappeared as of January 1, 2019?🙃

 

Oh no! They are just filed under 'I look here if nothing else is working' 😆 

[ThinkingPlus]

1 hour ago, Slagathor said:

For those asking about accuracy follow up:  USFS study was USFS Study

 

I looked at the laser rangefinders that did not require a reflector to grab a range of tested accuracy.  For the golf rangefinder, I can't find the link - it was buried about 8 pages deep in a Google search to find someone that actually tested instead of just regurgitating mfr specs.  But the golf rangefinder was tested at 50 and 100 yards and gave gross error of 1 & 2 yards compared to a measuring tape.  My assumption is that if you have a recent laser unit + prism/reflector on the stick, the accuracy may be better.  My stated assumption was that the stick would not have a measuring aid equipped for this discussion.

 

And for Mr. Bean - the unit that the USFS used was a stereoscopic unit with a baseline of ~18 inches or so.  So much different than the typical stuff we would use.  But if you wanted to push the rules...  And based on 15 years of shooting with rangefinder equipped film cameras, my assumption is that technique & proficiency with an optical rangefinder would allow you to bracket the distance by focusing from near-to-far and comparing to a far-to-near focusing technique.

That is a really old test (22 years) and is not representative of capability with laser rangefinders today.  Accuracy for most LRFs should be a few meters with precision around 1 - 2 meters with or without augmented targets.

[Slagathor]

19 minutes ago, ThinkingPlus said:

That is a really old test (22 years) and is not representative of capability with laser rangefinders today.  Accuracy for most LRFs should be a few meters with precision around 1 - 2 meters with or without augmented targets.

 

Agree, but was more interested in the numbers from there on the optical rangefinder and if you really wanted to challenge a rule regarding electronic rangefinders.  That tech has not changed, and I doubt anyone is testing them in this day and age.

 

With respect to the current gen of laser units, agree.  The number for that (that I cannot find the link for...) was 1 yard at 50 & 2 at 100 - which generally fits with your numbers and would be 2% error at those distances.  I'm not arguing against lasers here, more interested from the standpoint of a local rule that stipulates electronic vs. an unpowered device, per Halebop's initial post.  And, again, no idea if an optical stereographic rangefinder would compare to a tournament grade yardage book.

[ThinkingPlus]

1 minute ago, Slagathor said:

 

Agree, but was more interested in the numbers from there on the optical rangefinder and if you really wanted to challenge a rule regarding electronic rangefinders.  That tech has not changed, and I doubt anyone is testing them in this day and age.

 

With respect to the current gen of laser units, agree.  The number for that (that I cannot find the link for...) was 1 yard at 50 & 2 at 100 - which generally fits with your numbers and would be 2% error at those distances.  I'm not arguing against lasers here, more interested from the standpoint of a local rule that stipulates electronic vs. an unpowered device, per Halebop's initial post.  And, again, no idea if an optical stereographic rangefinder would compare to a tournament grade yardage book.

Most yardage books these days are created using laser rangefinders.  LRFs are the state of the art for distance measuring devices.