RE: Declinometer queries
Hello Tony, I think that was before my time.. gnomonically speaking. Would you include me on your list please? Thanks Rudolf Hooijenga 52-30N 4-40E -Oorspronkelijk bericht- Van: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Namens tony moss Verzonden: maandag 29 november 2004 22:45 Aan: Sundial Mail List Onderwerp: Declinometer queries Hi all, Many thanks for the enquiries about the drawing/jpeg I offered. I'll post a collective response later in the week when enquiries have ceased. Tony Moss - -
Declinometer queries
Hi all, Many thanks for the enquiries about the drawing/jpeg I offered. I'll post a collective response later in the week when enquiries have ceased. Tony Moss -
Re: Wall Declination Measurement
I've got that drawing of your somewhere but I can't locate it. Could you please send me a copy? thanks John - Original Message - From: "tony moss" <[EMAIL PROTECTED]> Cc: "Sundial List" Sent: Monday, November 29, 2004 9:46 AM Subject: Re: Wall Declination Measurement John Carmichael wrote: Subject: Wall Declination Measurement Hopefully, somebody from the sundial list will help us. This is my own preferred method of determining wall declination but, before originally adopting it, I needed to be sure that a) the 'nail' was truly pependicular to the measuring board and b) the plumbline/pencil line ran exactly through the axis of the nail. Without this certainty the results might be questionable so to that end I developed my 'precision declinometer' which I know has been adopted in various forms by other diallists. It uses a tapered 'gnomon' spike sliding in a machined vee groove*. The novel idea was to include a needle point in the butt end of the spike which punctures the recording paper exactly on its axis. For anyone who missed the previous offer via this list some years ago I can supply a gif and jpeg showing how it is made and used. Like John Davis I also prefer to take a number of readings over an extended period then take an average. * An accurately drill hole is almost as good but 'drilling is the least precise process in engineering' and unless a good sliding fit is obtained then the tip and needle point can wobble off centre whereas a vee groove constrains the spike precisely in two perpendicular planes. Tony Moss - -
Re: Wall Declination Measurement
I wrote a program that determines declination of a vertical wall using just a watch and a carpenter's square. It gives very accurate results if performed when the square's shadow is long. Be certain to follow directions closely, and measure the edge of the shadow as described in the method. Take a few measurements for consistency. Download it free at www.precisionsundials.com/walldeclination.exe Bill G. -
Re: Wall Declination Measurement
John Carmichael wrote: >Subject: Wall Declination Measurement >Hopefully, somebody from the sundial list will help us. This is my own preferred method of determining wall declination but, before originally adopting it, I needed to be sure that a) the 'nail' was truly pependicular to the measuring board and b) the plumbline/pencil line ran exactly through the axis of the nail. Without this certainty the results might be questionable so to that end I developed my 'precision declinometer' which I know has been adopted in various forms by other diallists. It uses a tapered 'gnomon' spike sliding in a machined vee groove*. The novel idea was to include a needle point in the butt end of the spike which punctures the recording paper exactly on its axis. For anyone who missed the previous offer via this list some years ago I can supply a gif and jpeg showing how it is made and used. Like John Davis I also prefer to take a number of readings over an extended period then take an average. * An accurately drill hole is almost as good but 'drilling is the least precise process in engineering' and unless a good sliding fit is obtained then the tip and needle point can wobble off centre whereas a vee groove constrains the spike precisely in two perpendicular planes. Tony Moss -
Re: Wall Declination Measurement
Gianna got in before me with the answer to your question. I use a version of the "nail in a board" method myself. I like to take several measurements, preferably over a couple of hours, to improve the accuracy of the measurement. As well as the horizontal position, I also record the vertical position of the shadow tip below the base ot the "nail". This can be compared with the sun's altitude and proves a useful double-check, allowing doubtful readings to be discarded. Regards, John --John Carmichael <[EMAIL PROTECTED]> wrote: Hello Carol: (c.c Sundial List) I'm back home and this morning I'm looking at your wall declination measurements. Unfortunately, I am not accustomed to using the nail method you used and I hesitate to comment because I don't want to make a mistake. I have heard of this method however. I am going to forward your letter to our Sundial List discussion group and hopefully somebody there will be able to check your measurements. But I was able to check your solar azimuth data that you got from your astronomy program. According to the program I use (The Dialist Companion), the solar azimuth at that latitude, longitude and time was about 20.45 degrees west of south, not 209 degrees. Just think about it. If the solar declination were 180 degrees west of south, the sun would be due north and that's not possible. 209 degrees would be towards the North East which is also impossible. Hopefully, somebody from the sundial list will help us. John - Original Message - From: carol arnold To: John Carmichael Sent: Monday, November 22, 2004 1:09 PM Subject: declination John, I was just having a go at measuring the declination of a window in my house - I am not convinced of the accuracy of my measurement of sun angle to wall,but I wondered if you could double check the calcualtions? The window was approx south facing. 22 nov 2004 at14.01 gmt I used a nail 92mm long on a vertical board and its shadow was 50mm to the right of the nail. So the sun angle to the wall is 28 deg 31min 23sec west of south. My astronomy program gave me azimuth of sun to be 209 deg 44min 31sec ie 29deg 44min 31sec west of south, for lat 51deg 25min 20sec North and long 2 deg 42 min 30 sec west. So I reckon the the wall faces 1 deg 13 min 8 sec west of south?? Regards and hope you dont mind my asking you about this, Carol Carol Arnold Stained glass artist, commissions welcome, please take a look at my stained glass website http://www.carolarnold.co.uk Moving house? Beach bar in Thailand? New Wardrobe? Win £10k with Yahoo! Mail to make your dream a reality.Dr J R DavisFlowton DialsN52d 08m: E1d 05m
Re: Wall Declination Measurement
I think the measurement of the wall declination with the nail method done by Caroil is correct. The azimuth of the sun is 29deg 44min 31sec west of south on the mentioned place and time. And thus the wall declination is: 29deg 44min 31sec - 28 deg 31min 23sec = 1 deg 13 min 8 sec west of south Willy Leenders Hasselt, Flanders in Belgium John Carmichael wrote: Hello Carol: (c.c Sundial List) I'm back home and this morning I'm looking at your wall declination measurements. Unfortunately, I am not accustomed to using the nail method you used and I hesitate to comment because I don't want to make a mistake. I have heard of this method however. I am going to forward your letter to our Sundial List discussion group and hopefully somebody there will be able to check your measurements. But I was able to check your solar azimuth data that you got from your astronomy program. According to the program I use (The Dialist Companion), the solar azimuth at that latitude, longitude and time was about 20.45 degrees west of south, not 209 degrees. Just think about it. If the solar declination were 180 degrees west of south, the sun would be due north and that's not possible. 209 degrees would be towards the North East which is also impossible. Hopefully, somebody from the sundial list will help us. John - Original Message - From: carol arnold To: John Carmichael Sent: Monday, November 22, 2004 1:09 PM Subject: declination John, I was just having a go at measuring the declination of a window in my house - I am not convinced of the accuracy of my measurement of sun angle to wall,but I wondered if you could double check the calcualtions? The window was approx south facing. 22 nov 2004 at14.01 gmtI used a nail 92mm long on a vertical board and its shadow was 50mm to the right of the nail. So the sun angle to the wall is 28 deg 31min 23sec west of south.My astronomy program gave me azimuth of sun to be 209 deg 44min 31sec ie 29deg 44min 31sec west of south, for lat 51deg 25min 20sec North and long 2 deg 42 min 30 sec west.So I reckon the the wall faces 1 deg 13 min 8 sec west of south?? Regards and hope you dont mind my asking you about this,Carol Carol ArnoldStained glass artist, commissions welcome,please take a look at my stained glass website http://www.carolarnold.co.uk Moving house? Beach bar in Thailand? New Wardrobe? Win £10k with Yahoo! Mail to make your dream a reality.
Re: Wall Declination Measurement
Hello John , the values written by Carol are all correct and very accurate and her wall faces exactly 1 deg 13 8 west of south In astronomy the azimuth values start from north and therefore a value of 209 deg corresponds, for the dialist, to 29 degs from South toward West. Regards Gianni Ferrari 44° 39' N 10° 55' EMailto : [EMAIL PROTECTED] - Original Message - From: John Carmichael To: carol arnold Cc: Sundial List Sent: Monday, November 29, 2004 2:55 PM Subject: Wall Declination Measurement Hello Carol: (c.c Sundial List) I'm back home and this morning I'm looking at your wall declination measurements. Unfortunately, I am not accustomed to using the nail method you used and I hesitate to comment because I don't want to make a mistake. I have heard of this method however. I am going to forward your letter to our Sundial List discussion group and hopefully somebody there will be able to check your measurements. But I was able to check your solar azimuth data that you got from your astronomy program. According to the program I use (The Dialist Companion), the solar azimuth at that latitude, longitude and time was about 20.45 degrees west of south, not 209 degrees. Just think about it. If the solar declination were 180 degrees west of south, the sun would be due north and that's not possible. 209 degrees would be towards the North East which is also impossible. Hopefully, somebody from the sundial list will help us. John - Original Message - From: carol arnold To: John Carmichael Sent: Monday, November 22, 2004 1:09 PM Subject: declination John, I was just having a go at measuring the declination of a window in my house - I am not convinced of the accuracy of my measurement of sun angle to wall,but I wondered if you could double check the calcualtions? The window was approx south facing. 22 nov 2004 at14.01 gmt I used a nail 92mm long on a vertical board and its shadow was 50mm to the right of the nail. So the sun angle to the wall is 28 deg 31min 23sec west of south. My astronomy program gave me azimuth of sun to be 209 deg 44min 31sec ie 29deg 44min 31sec west of south, for lat 51deg 25min 20sec North and long 2 deg 42 min 30 sec west. So I reckon the the wall faces 1 deg 13 min 8 sec west of south?? Regards and hope you dont mind my asking you about this, Carol Carol Arnold Stained glass artist, commissions welcome, please take a look at my stained glass website http://www.carolarnold.co.uk Moving house? Beach bar in Thailand? New Wardrobe? Win £10k with Yahoo! Mail to make your dream a reality.
Wall Declination Measurement
Hello Carol: (c.c Sundial List) I'm back home and this morning I'm looking at your wall declination measurements. Unfortunately, I am not accustomed to using the nail method you used and I hesitate to comment because I don't want to make a mistake. I have heard of this method however. I am going to forward your letter to our Sundial List discussion group and hopefully somebody there will be able to check your measurements. But I was able to check your solar azimuth data that you got from your astronomy program. According to the program I use (The Dialist Companion), the solar azimuth at that latitude, longitude and time was about 20.45 degrees west of south, not 209 degrees. Just think about it. If the solar declination were 180 degrees west of south, the sun would be due north and that's not possible. 209 degrees would be towards the North East which is also impossible. Hopefully, somebody from the sundial list will help us. John - Original Message - From: carol arnold To: John Carmichael Sent: Monday, November 22, 2004 1:09 PM Subject: declination John, I was just having a go at measuring the declination of a window in my house - I am not convinced of the accuracy of my measurement of sun angle to wall,but I wondered if you could double check the calcualtions? The window was approx south facing. 22 nov 2004 at14.01 gmt I used a nail 92mm long on a vertical board and its shadow was 50mm to the right of the nail. So the sun angle to the wall is 28 deg 31min 23sec west of south. My astronomy program gave me azimuth of sun to be 209 deg 44min 31sec ie 29deg 44min 31sec west of south, for lat 51deg 25min 20sec North and long 2 deg 42 min 30 sec west. So I reckon the the wall faces 1 deg 13 min 8 sec west of south?? Regards and hope you dont mind my asking you about this, Carol Carol Arnold Stained glass artist, commissions welcome, please take a look at my stained glass website http://www.carolarnold.co.uk Moving house? Beach bar in Thailand? New Wardrobe? Win £10k with Yahoo! Mail to make your dream a reality.
