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141 F'n Saint

About Cisco

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    Anarchist
  • Birthday 04/11/1946

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    Boat in La Libertad, Ecuador. Body in NE Victoria, 'Straya

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  1. Cisco

    Astrolabe Anarchy!

    This is why it pays to get set up and start watching the sun... through your sextant ... a few minutes before noon... And also ... especially if the sun is going to very high but really at any time at all....why it pays to calculate at least a 'rough ' noon altitude.... Better to set this on the arc than to try bring the sun down to the horizon... that will have you falling on your arse.... So to calculate the anticipated altitude.... lets take the simple case of you being north of the equator and the sun having southerly declination... As you know .... Obs Lat = ZD minus Dec So.. transpose and solve for ZD .... it becomes DR Lat plus Dec = ZD Subtract ZD from 90º .. 90º - ZD = True Alt .... Set this on your sextant arc ... point yourself in general direction of the sun ... put telescope to eye while looking at horizon and the sun should swim into view.... This ignores Semi Diameter and Total Correction and Index Error..... if you want to go the 'full Errol' just alter the sign on each before applying them for a more accurate sextant altitude. High altitude sights aren't that hard ... the problem with very high altitude noon sights is that the azimuth in the minutes before and after noon will change so rapidly... Meanwhile .... A rather nice magnetic compass with provision for a shadow 'pin' can be seen here https://wrights.co.nz/product/jupiter-magnetic-compass/ And another one here...scroll down a bit... on a bulk carrier. .. http://www.compassadjustment.com Not much use on a yacht in a seaway....
  2. Cisco

    Astrolabe Anarchy!

    No ... its a link to a pdf I have over at Docdroid...... quite safe..... I thought you were here to learn... no skin off my nose if you aren't... Confusing? This is confusing.... ' Also, one could get confused if the sun is nearly overhead. Consider a glance at the compass to preserve the sign of the zenith distance, no?' The PDF over at Docdroid was some stuff written by me 25 or so years ago when I was trying to make a quick buck out of 'the knowledge' before nobody was interested in 'the knowledge' any more .... who would have thunk it..... Last time I used celestial in anger was close to forty years ago...the twenty years prior to that - in a world of 2 or 3 months' leave after 12 months 'on articles' - it was a part of my daily life... At the end of the day ...'no matter me'... take it or leave it....
  3. Cisco

    Astrolabe Anarchy!

    Quite so...'no' is correct..... if you have taken a morning sight or if you have run up a DR from morning stars you have a DR longitude which lets you calculate the time of mer pass within a minute or so... you are not working out merpass to the second... hence getting out there a few minutes in advance..... When latitude and declination are almost the same that is a difficult one... sun will go from bearing 'east' to bearing 'west' in a flash ... even a shadow stick won't help .... because there is no shadow...well non to speak off Chapter 6, page 104 in particular, may help.... https://docdro.id/5rFQH7g
  4. Cisco

    Astrolabe Anarchy!

    You reverse work your noon site to find what the altitude should be....
  5. Cisco

    Astrolabe Anarchy!

    What we used to do with noon sights.... Establish... using daily pages of almanac... time of mer pass on that day..... adjust for your longitude...etc... Maybe 3 or 4 minutes before merpass start watching the sun... keep watching it as the altitude slowly increases..... keep watching it..... the moment its altitude starts to decrease.... read altitude... retire to chartroom....calculate latitude.... Easy peasy on a steady work platform..... Clever dicks would have already worked everything out and could then go the full 'John Wayne'... or was it Errol Flynn?... and read the latitude directly from the arc.... That worked like this ... your DR lat is 40º 30' North.... if you are actually at that latitude the sun's sextant altitude will be 50º 10'..... At local noon you read the altitude as 50º 12'.... sun is 2' higher therefore you are 2' closer to the suns GP.... therefore your Lat is 40º 28'N
  6. Cisco

    American Dumbass

    The original dumbass seems unable to make up his mind...one week planning to go to Guam, next week getting interviewed on Sky News ( aka 'strayan Fox ) about what bastards the Australians are cos they won't let him in , and then banging on about NZ. Or so it seems .... I still can't view the vids... I just glean what I can from the comments.... Interesting... I can see them if I embed them here.... Sky news bit near beginning...the rest is shit.....
  7. Cisco

    best mag for sailing binos

    I honestly don't remember a quartermaster ever telling me what to do... in fact quite the opposite. A warship's bridge - with a cast of thousands milling around - is quite different to being by yourself in the cockpit of a yacht in a seaway. That is quite different again to a merchantman's bridge where the norm was two bino boxes on the bridge front.... one box for the master's bins.... the other for the watchkeepers.... and in my first company a long skinny box for the ship's telescope.... which would have been handed down from ship to ship since the mid 1800's.... and had optics that showed it... Back on track....in my last day job the lookout's binoculars would last about a year...... I would wander up to the local camera shop and buy a new pair out of petty cash. I used to buy Tasco 7x50s... good quality for the price. I thought they went bust some years ago but they seem to have been reborn.... https://www.ebay.com.au/itm/Tasco-Essentials-7x50mm-Porro-Black-Standard-Binoculars/202834016418?epid=28027034952&hash=item2f39d978a2:g:3DgAAOSwLG9fA24L
  8. Cisco

    best mag for sailing binos

    I guess I am just silly then.... I don't even have a strap on either my Fujis or my Nikons for the very reason mentioned above.... If they may be needed they live in their comfy little nest under the dodger.. Want to look at something.... remove from nest.... take a look... return to nest... I'm not in the habit of dropping things whether they be my binos or a beer... Mind you I have been known to drop the occasional hint and the odd clanger...
  9. Cisco

    best mag for sailing binos

    You are lucky... I'm cross-eyed....
  10. Cisco

    best mag for sailing binos

    For starters I would not bother with a compass... most aren't illuminated and simply add bulk. I would agree about 7x50... but don't think you get much for £35..... Some manufacturers make excellent 'high end' binos but their lower priced offerings are a bit indifferent.. Fujinon comes to mind. You want to find something with 'fold down' eye cups.... although these can fail over time... stow them unfolded.. The Nikon hard 'click stop' eyecups are excellent and better than the rubber ones. If I was looking for a budget pair with good glass I would go for these https://www.bhphotovideo.com/c/product/319410-USA/Nikon_7239_7x50_Action_EX_Extreme.html I don't have a pair but do have a pair of their "Action Extreme" 12 x 50's ashore and have had their Action Extreme 8x 42s.... the latter were replaced with a pair of 10x42 Monarch 7s which I use afloat and ashore. ( I also have Fujinon FMTRs on the boat and a nice pair of Zeiss ashore .... I like good glass ) Moving right along... binocular straps are the work of the devil. Fine if you are standing a four hour watch with your Barr and Stroud 12x 50s on a nice stable platform such as the bridge of HMS Repulse ..... but on a yacht? Some prick will - sooner rather than later - pick the bins up... but the strap will hook around some bit of furniture and snatch them from their hands and that will be the end of that..... Likewise... wandering around on a yacht with your bins swinging around like an elephant's dong will soon lead to tears... If you must wander around with them hanging from your neck buy something like this... https://www.bhphotovideo.com/c/product/1549712-REG/riton_optics_xbh_binocular_harness.html Sweaty crew using the captain's binoculars? Stuff em.... don't let them near them....simple fix...
  11. Cisco

    American Dumbass

    Going to NSW from Tas is easy..... by end of November returning may be easy as well... https://www.abc.net.au/news/2020-10-02/tasmania-friday-covid-borders-update/12726536
  12. Cisco

    American Dumbass

    Stuck in the South West Pacific? Wondering where to go? Come to sunny Victoria... 'Victoria's Department of Health and Human Services (DHHS) confirmed the arrival of the group into Melbourne, but said its authorised officers did not have the authority to detain them.' 'Border Force refused to comment on the matter, directing The Age and SydneyMorning Herald to state authorities. Spokeswomen for the Victorian government directed any queries about the matter to the DHHS. A spokeswoman for Melbourne Airport said it had also been unable to reach the Victorian DHHS to understand the situation and were therefore unable to comment. A Victoria Police spokesperson declined to comment, stating the force had no jurisdiction over travellers at the airport. The NSW government, the Federal government and Sydney Airport have been contacted for comment.' That's from here https://www.theage.com.au/national/f....html#comments
  13. Easy for you to say........ NB... I have just sat down after an arduous day in the garden... almost time for a G&T...
  14. Cisco

    American Dumbass

    Glad you made that clear.... someone may have shamed you by graffiti-ing(sp) your boat if you hadn't... https://www.stuff.co.nz/business/123109396/covid19-semiretired-kindergarten-teacher-on-weekend-away-nabbed-vandalising-briscoes-store-over-wage-subsidy
  15. Only problem with that is she has no baby stay..... she has twin lowers either side...