Which planisphere?

[JOC]

I haven't got a planisphere yet, but get a huge amount of use from my mobile phone apps which can all show in red text!

[AdeKing]

10 hours ago, Mak the Night said:

I started off with this Phillip's one decades ago:

I started with this one sometime in the 1980s too and it's still on my bookshelf.

Now I tend to use the David Chandler version.

[Stu]

10 hours ago, LukeSkywatcher said:

There is only 2 planispheres on sale. One for the northern hemisphere and one for the Southern.

I thought that too, but apparently not. The David Chandler ones at FLO are available for a number of latitude ranges, including a specific one for Japan!

https://www.firstlightoptics.com/books/david-chandler-night-sky-planisphere.html

[Mak the Night]

57 minutes ago, AdeKing said:

I started with this one sometime in the 1980s too and it's still on my bookshelf.

Now I tend to use the David Chandler version.

They still make the Phillips' planisphere I think, although it has a blue border now rather than green. I've still got my Chandler planisphere, I don't get on with it. 

The Collins is bigger, and when you get your head around holding it the right way up, I find actually better to use. My old Phillips' has seen many years of use though. The plastic has worn making the 'window' more translucent than transparent lol.

[JOC]

In case it is useful I tried the previous Jodrell Bank Planisphere link and got a dead link.  Instead I searched using Google and found the instructions at this link http://www.jodrellbank.net/wp-content/uploads/2014/10/Make-a-planisphere.pdf  It sounds like something worth trying.

What I wondered - at the size these print up at do you end up with something, which, if you printed it onto clear plastic, would line up with the constellations if you held it up to the sky or would the scale not be correct?

 

[Geoff Lister]

I have the Philip's 51.5 degree one for the UK and the 42 degree at my holiday home in the south of France, but neither get much use. I tend to use Stellarium on my laptop to plan an evening's observing; and sometimes, when outside, SkyPortal on my tablet.

[Buzzard75]

The one I use began as a Kickstarter by Celestial Teapot Designs and Mike Kryzwonski. It's not specifically for more northern latitudes, but ranges from 30-60 degN. It's a really nice planisphere. Just be aware that, at 18" across, it's rather large. It can be purchased for $30 USD direct from their website or from other internet retailers.

 

[25585]

Phillips glow in the dark version.

[RT65CB-SWL]

I have the large & small Phillips Planisphere. The small one I keep in the car in the door pocket... and on the mobile 'phone Sky Safari and other astronomy apps.  

[L8-Nite]

7 hours ago, Buzzard75 said:

The one I use began as a Kickstarter by Celestial Teapot Designs and Mike Kryzwonski. It's not specifically for more northern latitudes, but ranges from 30-60 degN. It's a really nice planisphere. Just be aware that, at 18" across, it's rather large. It can be purchased for $30 USD direct from their website or from other internet retailers.

Thanks, I didn't know about this one. I like planisphere's, and have been searching for one of the classroom size models, around three foot to a metre in diameter. Seen one on a video by a UK astronomy vendor, but haven't been able to come across one for sale.

[LightInsomnia]

Probably a stupid newbie question but my Philips states above my head is marked by a blue cross but can't see one 

[Stu]

How about a virtual planisphere? I should use this more often for planning what to look at. It is called Star Disc Planisphere by AstroVisuals and is very handy. You can position it for anywhere in the world, manually Pan and zoom or use the phone sensors to position the map correctly. Also, you can easily set for any time in the future.

[LukeSkywatcher]

1 hour ago, LightInsomnia said:

Probably a stupid newbie question but my Philips states above my head is marked by a blue cross but can't see one 

Can you post an image?. All the ones i know of have a hole in the middle which you look at Polaris through (Northern hemisphere).

I had one of those glow in the dark ones. It was useless.

[Charic]

Entry doubled? could  MOD please delete this one! Thanks

[Charic]

3 hours ago, LightInsomnia said:

Probably a stupid newbie question but my Philips states above my head is marked by a blue cross but can't see one 

Cant find my Planetarium just now, but the one with a hole in is used to spy on Polaris when held aloft, and the 'blue cross' your looking for should be printed near Cassiopeia  ( the big ' W ' in the sky! ) on the planetarium.

[LukeSkywatcher]

12 minutes ago, Charic said:

Cant find my Planetarium just now, but the one with a hole in is used to spy on Polaris when held aloft, and the 'blue cross' your looking for should be printed near Cassiopeia  ( the big ' W ' in the sky! ) on the planetarium.

Really?. I suppose they can use any star in the night sky and have the planisphere rotate around it and show everything in the correct position relative to that.

[Charic]

As far as Im aware, the Planetarium 'must' be aligned to Polaris, not any star,  in order to accurately align the constellations on the chart, plus the Month/date/time (GMT) must also be set. After setup, you can use the chart for other calculations?

The cross may not be in the same position for every planetarium, depending on the printed edition and its Latitude, but  you just need to ensure that the Planetarium you purchase covers  the latitude you live at. This is printed on the Planetarium. I'm sure any shop in the UK will be stocking Planetariums most suitable for the British Isles.

[LukeSkywatcher]

6 minutes ago, Charic said:

As far as Im aware, the Planetarium 'must' be aligned to Polaris, not any star,  in order to accurately align the constellations on the chart, plus the Month/date/time (GMT) must also be set. After setup, you can use the chart for other calculations?

The cross may not be in the same position for every planetarium, depending on the printed edition and its Latitude, but you  do need to ensure that the Planetarium you purchase covers  the latitude you live at. This is printed on the Planetarium. I'm sure any shop in the UK will be stocking Planetariums most suitable for the British Isles.

Yes, all planisphere sold in the northern hem are set to Polaris. Our cousins in Oz dont have a particular pole star (yes, they mostly work on a star in Crux). But my point is........a planisphere could be designed to have any star as a central star,and the night sky rotates accordingly.

Stop the clock............sorry, that wouldnt work.

*senior moment*

[Charic]

No worries.
The other issue with the Philips cross, It's  small and colour coded blue on black! making it difficult to locate.

 

[LukeSkywatcher]

Ive never seen the cross on one. I'd imagine its almost invisible.

[Charic]

Found them!

BOTH 2011 & 2012  have the cross on the clear top surface.

 

[LukeSkywatcher]

X doesnt mark the spot. X is a long way off Polaris(central hole). By about 35 degrees by the look of it.

 

[Charic]

14 minutes ago, LukeSkywatcher said:

X doesnt mark the spot. X is a long way off Polaris(central hole).

It marks your Zenith when held aloft in the correct orientation nothing more!
Just corrected my text above, the cross on both Planispheres is on the top section ( the clear section) and is  fully rotatable, marking your zenith when set, so not fixed to a point on the main chart. 

It wont be totally accurate, just depends where you are, but the latitude for the 2012 chart is 51.5°, so if you live between Lizard and John-O-Groats, it should still work?  I'm 57° N.  and visually Polaris appears almost straight up for me.

[LukeSkywatcher]

Polaris is the pole star (in the northern hem). The central hole on planisphere represents Polaris when held up and aligned to time and date. I cant see how the X works.

 

[Charic]

When you set the planispheres date time, this alignment (Monthdate/time) takes place at the bottom of the sphere, when held in front of you, looking down at it!

Note North is at the bottom, South at the top?

You now hold the sphere above your head and look for Polaris through the central hole.  When you have acquired Polaris, the cross ( though you wont see it in the dark ? ) will indicate a position overhead, and the constellations printed on the sphere should be aligned with what you see visually, but only the section  of sky depicted through the oval aperture?

You now have to understand and visualise  what your actually seeing through that 'window', noting that anything on the edge of the 'view/window'  equates to targets low on your horizon, and working  inwards towards the central hole, there's a point overhead, which if you look carefully.............is marked with the blue cross,  your zenith, the point directly above your location. Thats the purpose, and how the 'X' works!

HTH.