miguel87

Dont let everyone put you of EQ mounts. My very first mount was EQ and I have never looked back. I think they are very user friendly personally.

Also you mentioned a couple of times about "can I see nebula with this scope"

That entirely depends where you are and which nebula. You can see the orion nebula with the naked eye in fairly good skies.

With bad light pollution such as Bortle 8 or 9, you probably wouldn't see any nebula even with 4 or 5 inches of aperture.

Hi Sarah,

Glad you are getting an opportunity to explore the night sky again!

Obviously everything I am about to say is my opinion only.

If your budget is limited then I would always advise going for a reflector. You clearly had a bad first experience but I dont think it should tarnish your opinion of all newtonians. Pound for pound you can get a better view out of a reflector.

I have a 8 inch newt upgraded from a 5 inch newt was my first. In reality, unless you have the EQ5 mount of better, the only thing you can take photos of is probably the moon. As soon as you try to attach anything to the eyepiece it will pull on the mount and what you were viewing will be out of shot and the added weight will mean the cheap motor wont rotate the mount at a constant speed. Also aiming your phone through an eyepiece when magnifying more than about 50x becomes very very difficult plus anything less bright will not register on your phone camera.

I tried several times using my DSLR with a 130p and EQ2 mount. Disaster, it's too heavy for the focusser, scope and mount.

My specific recommendation would be a skywatcher 200p. That is based on an inflexible budget.

Yes you can put 1.25 inch eyepieces in virtually any telescope you are likely to buy.

Mike

Nice case. Fingers crossed this one works out! It's just on old plastic hair clippers case!

Nice selection! I have 6 and 9mm Vixen SLV, 20mm Vixen NPL and 32mm SW Panaview. I suppose it is a posh-budget range! Hope to complete it with the 15mm BST and I use my Tal barlow quite a lot. Thanks again 

Amazing thank you very much. Exactly what I need!

How do you find the eyepiece?

Mike

Hi folks,

Another small DIY lockdown project, an eyepiece case.

I wonder is somebody could send me the measurements and/or outline of a 15mm BST starguider please. 

I do not own this eyepiece yet but it will be the last piece in my collection for the foreseeable future so my eyepiece case should include a gap ready for it.

Thanks

1 minute ago, CentaurZ said:

This chart that I created should be helpful. Near the top is a sinusoidal curve of Full Moon declinations, that illustrates the matter under discussion.

 

 

 

Perfectly illustrated. Beautiful thanks

Mike

I think seeing as we are so close in space the night sky would be exactly the same.

I cant decide about the north star. Perhaps a star 23.5 degrees south of the north star, not sure in which direction tho?

Planet movements might be slightly different for mars and perhaps venus.

Just a guess?

Mike

Brilliant thanks, I guess it was just something I never considered. Those cold winter nights with a full moon high up in the sky; it's not just pathetic fallacy but an actual difference in the prominence of the moon.

Great explanation with the zodiac.

Thanks

Obviously this whole self isolation thing has given me too much time to think.

I was reading 'welcome to the universe's by neil degrass tyson and co. A fantastic book in my opinion, and I was studying the simple illustration of the the sun, moon and earth with rotation axis labelled and earth's seasons illustrated.

Is it the case that full moons during summer are lower in the sky than those in winter? I am thinking this because the moons orbit is more closely related to the plane of the solar system rather than earth's equator.

I could be very wrong. Or perhaps I am right but it is common knowledge?

Thanks

Mike ✌

3 hours ago, Anthonyexmouth said:

it works all days, any day. as long as the sun shines. 

im not talking about the direction of the shadow, just the very tip of the shadow. that tip travels in a due east direction as the day progresses. 

This.

It’s not true, and that’s literally all I said.  But multiple times they kept persisting that it is accurate to around 1 and a half degrees.

6 minutes ago, michael8554 said:

Anthony suggested a method of finding true north.

It went off-topic with your meanderings into why it wouldn't work.

You had the chance to say that the sun was south at local noon, but you didn't.

Michael

I think If I told him the sun was south at noon he probably would have taken it as an insult.

Somebody said that they knew a very easy and very accurate way of doing it.

I explained that It wouldn’t work.

another person also backed the idea and I showed some evidence for my opinion.

The original poster was looking for an accurate method.

What did you want me to? Lie and say yeah it will work fine?

Just because they persisted in saying it was accurate isn’t really my fault. Surely I have the right disagree?

In fact I pretty much did say it works at noon because I said it depends what time you do it and could be wrong at sunrise and sunset??

If at any time of day anywhere in the world, you trace the shadow of the tip of an upright stick. Mark two points a period of time apart say 30 mins or so, draw a line between the points.

Does that line point accurately east and west and therefore be used to find true north?

You just came into the conversation and told us that at noon the sun casts a shadow which points south. Yeah, we all know that.

It's just completely off topic.

I'm not disputing what you say at all, it's just not what we are discussions. We are not trying to find a method. We are discussing the usefulness of a particular method.

Just now, michael8554 said:

"Solar noon happens at your location when the Earth's rotation brings your local meridian to the side of the planet that faces the Sun. From your perspective, the Sun, after having steadily gained altitude since sunrise, now reaches the top of the arch that its journey describes in the sky every day. At this moment, it appears due south, due north, or in the zenith position exactly above you, depending on your latitude and the time of year."

Good enough ?

Michael

I think you are having a different conversation to us.

We are talking about how accurate and universal the stick-tip east to west shadow line is.

2 minutes ago, michael8554 said:

You guys are making it so hard.

Open your planetarium, check it's got your location correctly entered, fast forward to tomorrow.

Click on the Sun

Click on info

Sun transits at 12:09 tomorrow.

Get your stick ready and mark the shadow at 12:09

Simples.

And yes, that worked good enough to permanently install my mount and have enough range to Polar Align.

Michael

It's currently near the spring equinox, we are at a moderate latitude and you chose the middle of the day. So it will work pretty well tomorrow 👍

That's my whole point. Depends when and where you do it.

What I dispute is that it works whenever the sun is up, all over the planet.

It can be very wrong.

The black arrow illustrates the axis of earth's rotation. So as you travel north and this line become increasingly perpendicular to the ground, you can see that the resultant hyperbole exists at an ever shallower angle and casts a steeper curve on the ground.

The relative angles cast on the ground at opposite ends of the curve are vastly different. If you set the north tripod leg of a telescope at a right angle to your supposed east-west line you can see how it would face in drastically different directions.

During the equinox the maximum amount of error (using the method at sunrise or sunset) moves with your latitude, from being 0 degrees out on the equator to 52 degrees out where I live in Swansea and so on further north

If you add in the effect of the seasons these errors would be even greater.

21 minutes ago, City9Town0 said:

Thank you for your explanation... the points were not new to me but I appreciate your patience and persistence. The thread was about  aligning the HEQ mount. The method is most certainly good enough for that... refinements such as knowledge of errors may even help....

This would get close enough to Polaris to start a polar alignment...

Anyway, I wait until sharpcap can find a few stars and away I go!

I won't go into compass errors due to friction or anomalies in the Earth magnetism if you want to be accurate... ( I do know what accurate means)

This is not helping the OP, to whom I apologise.

End of.

Dont give me end of haha. And dont say that it is still accurate enough to align a mount or find Polaris. If you angle your scope 50 degrees off north you will definitely not be able to find Polaris. 

I can give you a specific location and time and degree of inaccuracy if you like?

I already did that will the artic circle example.

Even if you did it in london on summer solstice at 9pm just as you were setting up to observe, you would be over 40 degrees off!

✌

If you happen to live not too far north or south and you use this method during the middle of the day it is a reasonable east west guide.

But it is not accurate and certainly not universal. I wouldn't use it to align a telescope for astrophotography!

I dont intend to argue I just know it doesnt work and I dont know how else I can explain it to you.

32 minutes ago, City9Town0 said:

The end points of the shadow are marked at the start and the end of a ten/fifteen minute period....... The straight line between these points is the East-West line (within a degree of so...)

The error direction is known so a bit of correction can be added with a smidgeon of guesswork. I'll be within 1.5 degrees...

No, as you can see from the graph and if you read the section on error calculation, this method could result in an error of over 40 degrees at a high latitude near to summer winter solstice.

Above the artic circle (imagine doing it at 1am till 1.15am in mid summer) it could be 180 degrees out as the sun travels back east from west via north!

1 minute ago, Anthonyexmouth said:

1. dont worry about the line of the shadow, its ONLY the tip you need, and that ALWAYS follows a STRAIGHT line. It works within the arctic circle, why woudn't it? 

2. It's VERY accurate if done with a thin/pointed stick. 

It wouldn't because in summer the sun doesnt set, so it would HAVE to draw a circle not a line

You can see the curve. The lines for the first and last hour would point in completely different diections

3 minutes ago, Anthonyexmouth said:

it extremely accurately marks true east-west. 

You're gonna ignore the circle that would be drawn by the sun within the article circle?

Or the fact that it is not a perfectly straight line unless you are on the equator?

It may well be rough but certainly not more accurate than the other methods mentioned.

At best it will be very approximate. I mean if you are above the article circle the tip will draw a circle?

1 minute ago, Anthonyexmouth said:

100% confident doesn't mean 100% right. 

sounds like it should be wrong but it works, you were obviously never a boy scout. 

You obviously never tested it!