Not sure if I'm going wrong.

[dcwales2012]

Help!

Skywatcher Explorer 150p 10mm, 25mm, 2x Barlow

Went out back last night - good clear skies. Tried both EPs had brilliant observation of the moon, however, when I went to look at the Planets:

Saturn in the East

Mars in the South

Vensus in the West

Jupiter in the West

I could see them clearly with the naked eye as brilliant white dots, however when I tried the scope all I got was brilliant white dot in the EP with four arms like a cross (X). I tried the 10mm on its own, then with the Barlow. I tried the 25mm on its own and then with the Barlow. I just couldn't make out anything. When I tried to focus in or out all I could see in the EP was the secondary mirror and cross hair, but this was not there when I observed the moon.

I have ordered a Skywatcher SP Series Super Plossl 7.5mm EP and will probably get the 6.3mm at a later date, after reading the sticky on this forum by Warthog on EPs.

The Scope appears to be collimated correctly as far as I can see, BTW its new.

In the meantime can anyone tell me, is it usual to get such poor viewings with a 150p?

What EP should I be using, or getting.

Appeciate any help.

[Kedvenc]

Did you use the Barlow when viewing the moon?

[Catweazel]

Hi

The cross you are seeing is diffraction spikes from the spider vanes in the 150P.

When you say that all you coud see was secondary mirror & cross hair, did you have an eyepiece in at the time? With EP'S in, the different ones should have made a difference to the size of the dots, and Mars should be orangey red, not white? Does that sound right?

Also, did you find the planets in the finderscope first? Is the finderscope lined up OK with the main scope? Try checking this out during daylight, using a distant object to line them up, it will help a lot. You may have thought that you were looking at planets, but have been looking at nearby stars, which would explain "white dots", in the EP'S.

[AstroMadBloke]

Hi Dave I would say check the collimation, although the scope is new the collimation could have been knocked out in transit. I check the collimation on my 10" Newtonian every time I move it even if it's from the house to the garden. The other thing is to check for dew on the mirror or eye piece lens as that will give you problems.

Hope this help,

Pete

[hemihaggis]

sounds like you were looking at stars , you should see colour on jupiter and mars ,

[Carbon Brush]

At this magnification, the planets should show as small discs and stars as points.

If there is any doubt about finder/scope alignment, check on a distant object in daylight.

Collimation. Use very high magnification on a bright star. It should show a point, or very small circle, when in focus. As you move in/out of focus, it becomes a circular blob. If it is one sided, or has a tail like a comet, then collimation is off.

Do this check with the star near the centre of view. Some eyepeices can give dodgy views towards the edge.

Finally. last night was very humid. Might you have had condensation on the glassware?

Hope this helps.

David.

[dcwales2012]

Hi,

Many thanks for the replies.

Kedvenc - No, I didn't use the Barlow to look at the moon, the two EPs were good enough. I only used the Barlow to view the planets.

Catweazel - Yes, to EPs. With the difference EPs in it made no difference. What I was getting was a white dot with a cross(X), focus out diffraction spike. Focus back in again white dot(X), add more focus diffraction spike.

Yes to finding the planets in the scope first. I had set up telescope in the daylight to a chimmney pot some 600 metres away, then centred the scope to the same spot.

Astromadbloke - my 150p was free from condensation, I checked it against the moon on a number of occasions - and it was clear as a bell. I also removed the EP from time to time and they were clear on both sides. I looked down the barrel, so to speak and could see no dampness on the mirror, I took out the EP and there was no dampness on the Secondary.

Hemihaggis - I'm not convinced I was looking at stars. Vensus and Jupiter were clearly the two brightest objects in the western sky last night and quite easy to find in the scope.

David - Collimation, none of the objects; Moon the exception, I was viewing last night had tails or one sided. Just white dot with a cross (X).

David - if my EPs are only going to show a small disc as a planet, what EP strength should I go for?

Could I have a dodgy Barlow? Is there any way to find this out?

Your help is very much appreciated.

[Kedvenc]

I know this may sound stupid but (and I admit to having done this). When I first used the supplied barlow, the bottom lens cap was quite tight so I took it off by twisting and I actually unscrewed the lens of the barlow with the cap without realising i.e. I'd removed the actual lens of the barlow leaving nothing but a tube. This did exactly what you are describing as the EP is then moved further out and could not achieve focus. Is that possible or am I the only numpty?

[Carbon Brush]

Taking your scope as 750mm FL. This means the 25mm EP will give mag 30x magnification. or 60x with the barlow.

This is a bit low for looking at planets to get detail.

Unfortunately quite a few people reprot the stock 10mm EP as being not much good. Mine is no better than a dust plug! A 10mm EP will give you x75 on it's own, and x150 with the barlow. Much better numbers for planets.

Hopefully a decent 7.5mm will give you good results, x100 without the barlow.

A a rough guide. The moon is about 30arc minutes apparent diameter. Half a degree. Jupiter is more like 30arc sec. That is 1/60 the moon size. So viewing Jupiter in detail really calls for turning up the magnification.

The kit you already have will give you lots ot look at. Fantastic results on the moon, looking at craters, etc. With the 25mm EP on it's own you can catch the deep sky objects like M42, M45. Though is moon is going against you right now by brightening the sky.

Any new scope takes a while for you to get familiar and get the best from it.

Stick with it and keep asking... David

[Moonshane]

Taking your scope as 750mm FL. This means the 25mm EP will give mag 30x magnification. or 60x with the barlow.

This is a bit low for looking at planets to get detail.

Unfortunately quite a few people reprot the stock 10mm EP as being not much good. Mine is no better than a dust plug! A 10mm EP will give you x75 on it's own, and x150 with the barlow. Much better numbers for planets.

Hopefully a decent 7.5mm will give you good results, x100 without the barlow.

A a rough guide. The moon is about 30arc minutes apparent diameter. Half a degree. Jupiter is more like 30arc sec. That is 1/60 the moon size. So viewing Jupiter in detail really calls for turning up the magnification.

The kit you already have will give you lots ot look at. Fantastic results on the moon, looking at craters, etc. With the 25mm EP on it's own you can catch the deep sky objects like M42, M45. Though is moon is going against you right now by brightening the sky.

Any new scope takes a while for you to get familiar and get the best from it.

Stick with it and keep asking... David

I do agree with this to some extent but I was using a 6" f5 last night and this provided detail (at least the main cloud bands) with a 15mm plossl (60x).

I think the answer is to observe for a little longer and await the point where the eye starts to see detail. If you have a moon filter use this - it may help. with planetary observing you need to stare (with blinks of course!) for a good half an hour to start seeing real detail. the scope needs to be cooled (at least 30-60 mins) and well collimated too. it's an f5 and needs to be fairly close to spot on. what are you using to collimate?

Mars really needs 150x at least to see anything like detail but Saturn's rings should be clearly visible at 60x and venus should show the phase (like a mini moon) but no detail.

[hemihaggis]

sound advice from davidvalentine and moonshane

[Catweazel]

Yes, to EPs. With the difference EPs in it made no difference. What I was getting was a white dot with a cross(X), focus out diffraction spike. Focus back in again white dot(X), add more focus diffraction spike.

Yes to finding the planets in the scope first. I had set up telescope in the daylight to a chimmney pot some 600 metres away, then centred the scope to the same spot.

OK, the only other thing that occurs to me is that you may have been focusing in and out too quickly. Try turning the focuser really slowly to achieve focus.

if my EPs are only going to show a small disc as a planet, what EP strength should I go for?

When viewing Jupiter, for example, you should find it much bigger than a dot with a 5mm EP (10mm + Barlow), which gives you 240x this will be at the limit of the 150P's magnification. Even with a 10mm, you should get 120x, and get a small panet, with some sharp detail & cloud bands.

Could I have a dodgy Barlow? Is there any way to find this out?

try looking at the moon with it, and see if it looks anywhere near as sharp as wiithout it. This will give some idea if it's OK. I doubt that it is dodgy though

[Tinker1947]

Always use the 25mm when you first look at a object, the chances of the object being the right one are 100's of time better than using a low (mm) EP, I would recommend a wider view EP this will enable you to find much more in the way of DSO's then change to a high mag EP once its centered. My own wide EP is a 36mm 82' EP, the last 10 DSO's i would have missed 8 of them if i had been using the stock 28mm EP.

[Catweazel]

Always use the 25mm when you first look at a object, the chances of the object being the right one are 100's of time better than using a low (mm) EP, I would recommend a wider view EP this will enable you to find much more in the way of DSO's then change to a high mag EP once its centered. My own wide EP is a 36mm 82' EP, the last 10 DSO's i would have missed 8 of them if i had been using the stock 28mm EP.

Good advice! I always start with a 25mm for planets and a 32mm for DSO's

[Doughzer]

May sound stupid but, do you have the 2" socket along with the 1".25 too on at the same time?

[badgers]

Always use the 25mm when you first look at a object, the chances of the object being the right one are 100's of time better than using a low (mm) EP.

I've the same scope, and you'd have known for sure if you had jupiter in your sights.

The stock finderscope on the 150P is a bit poor and it looses alignment very easily. Possibly you had jupiter centred in the finderscope, but the scope was pointing at something else like Catweasel said.

Find a nice bright star, centre it in eyepiece, then go to the finderscope and adjust the knobs until its centred on both, that'll make life much easier.

Again, the advice to start with the lowest power eyepiece first and adjust focus every time you change eyepiece is critical.

Here's a webcam capture of Jupiter from my 150P, you should easily be able to make out bands.

At the eyepiece this will be much brighter with moons visible.

_ZuMKvkCPMQ

* This is easier to view on the youtube site, it comes up very small here

[brantuk]

I had a 150P a few years back and it's a smashing little scope which gave me a great intro to the hobby. However, it wasn't untill I upgraded to higher quality eyepieces that I realised just how good the scope is.

Take it to an observing session at your local astro soc and someone will let you try better eyepieces and you'll find the scope comes alive - the supplied 10mm and barlow are usable but pretty naff - the 25mm is just ok.

Avoid the low end eyepiece kits which imho are mostly poor value for money - buy individual eyepieces and budget on at least £45-£65 per piece new, or £30-£50 s/h. A good vfm barlow is the Tal 2x or Celestron Ultima - also consider a good zoom like the Baader Hyperion. All the advice above stands as well - especially the collimation comments. HTH

[dcwales2012]

Hi,

Many thanks for all the replies - good sound advice.

Checked collimation and its OK.

Check Scope alignment OK.

Went out again last night, even though slight high cloud and misty. Put all my effort into one planet; Saturn, saw a white round disc, black suuround and then a white haze, at one stage I thought I observed the rings.

I have worked out the problem - I'm expecting too much too soon.

Hopefully the 7.5mm will help, or I'll just get 5mm to add to the collection.

Thanks again.

[Moonshane]

Hi,

Many thanks for all the replies - good sound advice.

Checked collimation and its OK.

Check Scope alignment OK.

Went out again last night, even though slight high cloud and misty. Put all my effort into one planet; Saturn, saw a white round disc, black suuround and then a white haze, at one stage I thought I observed the rings.

I have worked out the problem - I'm expecting too much too soon.

Hopefully the 7.5mm will help, or I'll just get 5mm to add to the collection.

Thanks again.

It really does not sound like you are looking at Saturn. even at 60x you'll clearly see the rings and a sharp but small planetary disc. are you sure that you are not looking at the double star Porrima in Virgo? It's bright, yellow and about the width of your hand on an outstretched arm to the left of Mars.

[Kedvenc]

With the 10mm and barlow giving x150 the rings should be pretty obvious and have a real yellow colour. Are you sure your looking at the correct object?

[Rob L]

I agree, it doesn't sound like Saturn.

Even at quite low powers Saturn is unmistakable.

What time were you observing? Even at midnight Saturn is still very low in the sky at the moment.

[hemihaggis]

yep it really does not sound like you were viewing saturn , ... the first time i saw the ringed planet i giggled , it looks amazing and unmistakable even at low power ie 25mm , at the moment saturn wont really be high enough to have a good view until 3 0r 4 am ... what time did you try to view ...

jupiter is really well place to view just now , you can see it as soon as it gets dark ,

silly question ... are you using the focuser ??

[Dove]

hi im getting the EXACT same problem you started of with, how did you resolve this ?

Thanks.

[Dove]

Help!

Skywatcher Explorer 150p 10mm, 25mm, 2x Barlow

Went out back last night - good clear skies. Tried both EPs had brilliant observation of the moon, however, when I went to look at the Planets:

Saturn in the East

Mars in the South

Vensus in the West

Jupiter in the West

I could see them clearly with the naked eye as brilliant white dots, however when I tried the scope all I got was brilliant white dot in the EP with four arms like a cross (X). I tried the 10mm on its own, then with the Barlow. I tried the 25mm on its own and then with the Barlow. I just couldn't make out anything. When I tried to focus in or out all I could see in the EP was the secondary mirror and cross hair, but this was not there when I observed the moon.

The Scope appears to be collimated correctly as far as I can see, BTW its new.

Appeciate any help.

thats the exact problem im getting at the moment when trying to view Mars/Venus/Juipter.

But soon as i look at the planets im getting Secondary mirror and the Spider...