DISTANCES

[REDCHEQHEN]

What would you do? Not been happy with our distance measurements, a friend came and measured with a hand held GPS system he uses for fell walking, accurate to 17 feet (he told me)

 

The distances have come back for the GPS measurement, and all our distances are out by between 35 and 80 yards - (there are two distances that are shorter, but we don't fly those race points) working back over, we would have had two higher positions in the club and combine on these measurements. When I suggested to my other half that we needed remeasuring, he said, if the same method was used, it would just be the same as before anyway. How accurate are the different measurement methods - and what would you do?

[pigeonpete]

hi redcheq, i would say that gps is more accurate than anything else if used correctly

[Guest]

hi ....they recalculated our distances last year...most of use lost 8-10yrds

[Pompey Mick]

It is imperative that all distances for any organisation are calculated in the same manner.  GPS is accurate for calculating a loft location as long as it is used correctly, the contour of the surrounding land can affect it, i.e. hills close by that can bend a satellite signal also security aspects can affect readings.

I don't know the reason behind your discrepancy RedCheqHen, are you in a built up area? Is it easy to locate your loft ?  I have relocated several new members to my Club (Club Rule) and the relocated distances have always compared favourably with existing ones, but my members live in built up areas which make loft location relatively easy.

Who calculated your new distances, because the RPRA has banned the use of GPS in recent years only accepting maps and they changed their method of calculation in 2003 making all earlier distances defunct.

[Guest]

Hi Mick could you point me in the direction of where to find out about the RPRA  rule change and what method for loft measurment ? thank you       andy

[Pompey Mick]

With the RPRA I have to send to them an Ordnance Survey map of suitable size on which the required loft location has been marked by pricking the map at the required position. They then calculate the Lat & Long, and from that calculate the required measurements.  The Latitude & Longtitude is then entered against your RPRA  Code No and any future measurements are calculated by quoting the Members Code No.

GPS was used 4 or 5 years ago by some members but the RPRA in their wisdom decided not to use it because of possible errors of use. The Map does give a permanent record of the loft location.

[Guest]

Thanks for the reply Mick . Would you say that present system was wholly accurate or .............. ?                                thank you     andy 8)

[PIGEON_MAN]

Weather or not gps is more accurate or not doesn,t come into it if you are governed by the rpra then you must go by their rules which states that all loft locations are to be calculated from ordnance survey,Redcheqhen if you are not happy with your distances i would ask your club secretary if he will remark your loft,this should only cost you £2.50 plus the postage for the return of the map.

[REDCHEQHEN]

Club secretary doesn't do them, not governed by the RPRA, but same method used - we will be asking for a recalculation.

[Guest]

Hello Tony how is the remarking done ? at £2.50 cost how much work goes into checking its accurate ? not picking fault but very curious !

[PIGEON_MAN]

Hello Tony how is the remarking done ? at £2.50 cost how much work goes into checking its accurate ? not picking fault but very curious !

 

The remarking is usually done by the secretary of the club or another official,he basically takes the map to the fanciers house and usually along with the fancier they agree where the loft is suituated and then puts a needle through the map and then writes on the back the members name.the £2.50 is the cost the RPRA make for calculating the lat. and long.from the hole in the map.as for checking the accurasy well that is down to how accurate the secretary marks the map in the first place.

[Guest]

I think the way locations are identified is farcical. GPS is not accurate because of the reason that Pompey has already given and also perhaps as important the location of the satelite that is used at the time of the mapping, this can give a different reading as I understand dependant on where it is in relation to the earth. However it must be far more accurate than pin pricking on a large scale OS map of 1:50,000.

I am surprised that clubs don't have their own large scale maps purchased from thier local planning dept . In 1972 when I set up a new club in the South Wales Valleys, I purchased sufficient maps to cover all our area at a cost I think at the time of about £24 a week's earnings for a well paid working man. Those maps clearly showed the back gardens of houses and you could be pretty accurate.

In a rural area where I live now it would be far more costly I appreciate but in the urban ares I would have thought it made a lot of sense.

I think this is a very neglected area open to abuse and the RPRA should revisit GPS, there will have been technological advances in these few years and there will be far less error I would suggest than that encountered from pin pricking.

[birdman55678]

All concourse reading must be taken with the same GPS unit, if that is the case then you have a problem.  Ed

[PIGEON_MAN]

ALBEAR,I agree with you the marking of someone,s loft with a needle cant be the best way with all the technollogy that is around now,but then again probable the fact that one transporter may be 20 or 30 yards up the field from another thats liberating birds in the same race is also a farce,as well as the liberater going by the time on his wrist watch which as probabley not been checked with tim when he liberate,s,so the fact that your distances may be out by a couple of yards is no more of a farce.the maps that we use in our club are 6 inches to the mile which i think are as stated by the rpra,not sure if that is smaller or larger than what you quote.I can remember buying some of these for the club for £6 each,I believe they are about 50-60 now.

[Guest]

Ihave visited a website showing my home location , to get the co-ordinates for my loft .  Three times i placed the arrow head where i think my lofts are located and 3 times got a different map (long/lat) reading anything from 5 - 7 yds difference , not a great deal i know but .... how accurate were my original readings done by the club ?                   ANDY 8)

[PIGEON_MAN]

Andy,the only thing i can say to you if you are not happy with your loft location is ask the secretary if he will remark your loft for you,any decent secretary would do this i,m sure,it may even be an advantage to the rest of the members,especially if they find that you are flying longer than you should be.

[Pompey Mick]

Hi North Wales Novice,

What website do you use for your Loft Location?  I thinka 5-7 yds difference is as accurate as you would want , an awful lot of loft set ups spread over an entire garden which can be anything up to 10 yds X 30 yds. How many fanciers have a different loft location for each loft?

In my instance with small city back gardens I normally *expletive removed* the centre of the garden, it is quite easy with a decent map to get an accurate location.

As I said before,due to a Club rule, all new members have to have their lofts re-pricked on our maps and I have found the new distances in all cases to be within 5yds of the originals.

[Pompey Mick]

Sorry about the'expletive deleted' it would seem that a common English word used correctly has obviously upset an American based checklist. I think you can all guess the 'expletive deleted', but if you dont, here it is

                                               ' p***k.

 

  

[Guest]

Pompey, if you are skilled at pin pricking and a good map reader yes you may get within 5 yds, but if the person that did it the first time got it wrong, s/he may well get it wrong the second time, 5 yds within the first reading sounds ok , unless of course the first reading is 15 yds out! 1:50 000 scale is quite poor have you considered the size of the area a pinprick covers?

Accept the point about the transporter not going from the right spot, but at least you are competing on a level playing field with all the birds on board. And even at a small distance apart the race winners who break quickly will have little advantage over each other as they will tend to group (I think!!)

[PIGEON_MAN]

ALBEAR,could you tell me what a map 1:50,000 scale is in inches to the mile,as the  ones we are suppose to use are 1:10,560 which is 6 inches to the mile,does that make it better or worse in terms of accuracey,so long as the mark is in the right place of course.

[Guest]

Hi Tony this is  an inch and a quarter to a mile (1:50000) and is the landranger OS map, the explorer os map is two and a half inches to the mile as are the outdoor leisure OS maps.

When I moved to Devon and enquired I was told by the RPRA that the standard OS map (landranger) was acceptable and my loft was located using such a map, and only last week I pin pricked for a new member using one.

But look at this way, one inch = 1760 yds, so on such a map if you put 1760 pinpricks next to each other then that should be no more than one inch across; now I know a pin *expletive removed* is small but do you think you could get 1760 in a row next to each other in less than an inch? (I know it would be impossible by hand but I'm sure a machine could be set up to do it). Oh and another silly point, how big is a *expletive removed*  , I mean what if the pin is a different size each time?

[Guest]

pr**k is a naughty word! that's a very intelligent piece of software because it was meant to be a double entendre in the second instance but not the first

[Guest]

oops in post above should read 1760 in inch and a quarter,

[Pompey Mick]

My Club maps are 1:10000 which gives blocks of houses and gardens, I would think that 1:50000 gives nowhere near  enough clarity of detail for the purpose of pin p****ing. To cover Portsea Island  about 3mls wide and 2.5 mls deep we have four maps. I did use a greater scale map once but it was more guesswork in the first place and the RPRA rejected it anyway.

I've attached an A4 scan of a part of one of our maps if you enlarge it to full size you can see the detail available. (Southsea Common is the Portsmouth Lib Site)

[Guest]

Mick, I think that is a very good scale to use. the trouble now is the cost of buying such maps as I understand it.