Guest Simes Posted November 22, 2012 Share Posted November 22, 2012 Morning everyone, Just after a bit of advice, after the second time of using my new scope - it's all new to me, so be gentle with me! The Scope is a Celestron Astro-master 130eq with motor drive - I know it's not really a class act, but it was inexpensive and an early Christmas present from 'er indoors - and will hopefully be good enough for me to decide if star watching holds the same pleasure now as it did when I was a little chap of 10, when I had a 60X60 refractor and spent night after night watching the moon, and drawing maps of it... Scroll on 40 years and we arrive at last night. I had a play on Sunday night with the scope, but last night start nice and clear and I had fewer other distractions! I set up in the garden - early doors the moon was nice and clear, and then of course, Jupiter dominated the sky. I live on a junction on a modern estate that is over blessed with street lights - one that shines over the garden fence and is so bright you can read a newspaper in the garden at night, and one slightly further down the road that is almost due south - so my viewing is limited with lampposts to the east and south, trees to the north and the house to the west! Earlier in the evening Jupiter was looking good, with 3 moons easily visible and one more just peeping out from the disc of Jupiter, that one disappeared later, not sure if it had gone behind Jupiter or if the seeing had just got a bit worse. I do have a question though (if I may) - using the supplied 20mm eyepiece I could discern bands on Jupiter (that gives me a magnification of about 32X), and I think I could discern them through my new eyepiece (6.5mm Plossl Meade 4000) which gives me 100X. One both Jupiter was a sharp disc and the moons sharp points of light. But later in the evening the 100X was just giving a blurred image - the edges of Jupiter were no longer sharp. On the 20mm it still looked OK though. Was this because the 'seeing' deteriorated or because the scope/eyepiece are rubbish - or a combination of the two! I am not sure about the collimation of the scope - I /think/ it's OK - a star defocussed when in the centre of the view stays symmetrical around the shadows of the secondary and the spider... As you can tell, I don't really know what I'm on about, so all and any help is gratefully received! Link to comment Share on other sites More sharing options...
Daz Type-R Posted November 22, 2012 Share Posted November 22, 2012 Hi Simon. Nothing wrong with your scope, a cracking little starter scope. With regards to your views, it sounds like conditions got worse, if you had good sharp views at 100x earlier in the night, then they got worse, down to either atmospheric conditions or your kit started to dew up or both. Also, remember, that you are also magnifying any imperfections as well as the object you are viewing, so at 100x mag, your not just magnifying Jupiter (for example) your magnifying cloud, bad seeing etc etc. If your views were bad all night, I would say bad seeing conditions or poor collimation, as they were good then got worse, then I would say bad seeing conditions or dew. Hope that helps. Link to comment Share on other sites More sharing options...
Guest Simes Posted November 22, 2012 Share Posted November 22, 2012 Thanks Daz, I'm hoping that's the case - I peered down the end and couldn't see any dew on the primary, but there could hve been on the secondary I guess... I'll just need to play more I think! Link to comment Share on other sites More sharing options...
Daz Type-R Posted November 22, 2012 Share Posted November 22, 2012 Another thing, (i`m not 100% sure of this so please wait for a more knowledgeable person to correct me if wrong) the highest practical magnification with your scope is 307x magnification - in this country with our weather you can ignore this. I think (????) that if you divide this mag by 3, the result is more likely what you can expect in good old Britain. So a 3rd of 307 = 102x magnification. (ignoring the remainders) You may of been pushing the highest usable magnification of your scope, as the 6.5mm ep gives you 100x mag. I think, using your 6.5mm, you may need really good seeing conditions, any thing other that that, you won't get perfect focus, things will look blurred. Link to comment Share on other sites More sharing options...
Guest Simes Posted November 22, 2012 Share Posted November 22, 2012 That would sort of make sense! I might look into getting a decent 12mm eyepiece for the mid-range views and when conditions don't allow the 100X mag (12mm would be about 50X). I have a 20mm erecting eyepiece, that seems OK - came with the scope, and a 10mm that came with the scope, but that's a rubbish eyepiece and gives awful chromatic aberration - a blue and a red image appear just about either side of Jupiter! Link to comment Share on other sites More sharing options...
Perkil8r Posted November 22, 2012 Share Posted November 22, 2012 It was also quite damp round here, dew was a big issue for me last night. It could possibly be that the secondary had a bit of dew on it. There was more high cloud about later on in the evening though so that would be my bet. Link to comment Share on other sites More sharing options...
Daz Type-R Posted November 22, 2012 Share Posted November 22, 2012 I would wait until somebody else either confirms or denies my comments, I wouldn't want you to waste your money on a new ep for the same thing to happen. Link to comment Share on other sites More sharing options...
Guest Simes Posted November 22, 2012 Share Posted November 22, 2012 Cheers all, like any newbie to a hobby, I'm desperate to get cracking! Some good news (for me) I've been onto the council about the street lights and they are going to come and fit 'shades' on them to reduce the light in the garden, and have a longer term plan to set them to part-time working, probably going off at midnight! So a result there! I'm already thinking that I should have bought a better scope, and a T mount, and more eyepieces, and dew shields and heaters and warmer togs etc etc! So, as you say, it makes sense to wait and do nothing for a while and see how things progress! Link to comment Share on other sites More sharing options...
Craig Posted November 22, 2012 Share Posted November 22, 2012 I would wait until somebody else either confirms or denies my comments, I wouldn't want you to waste your money on a new ep for the same thing to happen. I think that advice is sound. My 32mm gives me 73x mag in my scope and I find that the most pleasing viewing. if I change to a greater mag eyepiece I notice a distinct drop in the quality of the view. 117x is the further I have pushed it whilst being happy. I think I might move to the Atacama Desert. Link to comment Share on other sites More sharing options...
Guest Simes Posted November 22, 2012 Share Posted November 22, 2012 Heh :-) Sounds like a plan! Send plane tickets for (long) holidays to your old chums! My worry is the month I'd be with you would be constant dust storms. Link to comment Share on other sites More sharing options...
Guest DN18 Posted November 22, 2012 Share Posted November 22, 2012 "I'm already thinking that I should have bought a better scope" (er indoors) made a very good choice. The 130 AM is a cracking little starter scope. You can get a lot worse for the money As above have advised, dont get carried away with high powers. Stick with low-medium E/Ps that will suit this scope better Link to comment Share on other sites More sharing options...
Guest Simes Posted November 22, 2012 Share Posted November 22, 2012 Thanks DN18. Hopefully we'll get some more clear nights soon! Link to comment Share on other sites More sharing options...
T A WOW Posted November 22, 2012 Share Posted November 22, 2012 Hi Simon. I've got the same scope as you (but as you can tell by my sig I'm not a massive fan) I used to get the same problem with mine, the secondary mirror being so close to the opening. Make yourself a dew shield. Decathlon camping mat is really good and some sticky Velcro. Costs about £7 all in all. Also don't get the celestron eyepiece & filter kit (the one that retails for about £140 ish) if you don't lke the 10mm eyepiece the scope came with you wont like that kit. The only decent one in there is the 32mm. I foolishly bought all my kit before I joined, without asking anyone for advice. (oopsy) Anyway. Hope you have a better time with your scope than I have with mine. Link to comment Share on other sites More sharing options...
catman161 Posted November 22, 2012 Share Posted November 22, 2012 Welcome to EMS Simes Link to comment Share on other sites More sharing options...
Guest Simes Posted November 22, 2012 Share Posted November 22, 2012 (edited) Hi Simon. I've got the same scope as you (but as you can tell by my sig I'm not a massive fan) I used to get the same problem with mine, the secondary mirror being so close to the opening. Make yourself a dew shield. Decathlon camping mat is really good and some sticky Velcro. Costs about £7 all in all. Also don't get the celestron eyepiece & filter kit (the one that retails for about £140 ish) if you don't lke the 10mm eyepiece the scope came with you wont like that kit. The only decent one in there is the 32mm. I foolishly bought all my kit before I joined, without asking anyone for advice. (oopsy) Anyway. Hope you have a better time with your scope than I have with mine. Cheers - I did look (briefly) as the Celestron kit, but my experience with the supplied eyepieces put me right off! I'll have a bash at a dew shield - anyone got a picture of what it's meant to look like? I quite like the scope - I appreciate it's never going to replace Hubble - but most of the right-ups imply it's OK for the money. So, hopefully that will be proven to be true. The tripod seems OK, but the plastic bits in the middle look fragile - I might make up a wooden replacement for them as it will be stronger and perhaps act as a damper too. Focus tube on mine seems nice and square with little flop - so there is hope there that mine is middle of spec and perhaps yours is maximum flop end of spec? I bought a Meade Series 4000 6.4mm eyepiece, and although the seeing wasn't great, it had about no chromatic aberration - so I've ordered another at 9.7mm... Edited November 22, 2012 by Simes Link to comment Share on other sites More sharing options...
Daz Type-R Posted November 22, 2012 Share Posted November 22, 2012 This should give you an idea...... />http://www.firstlightoptics.com/dew-prevention/astrozap-flexible-dew-shield.html Link to comment Share on other sites More sharing options...
Guest Simes Posted November 22, 2012 Share Posted November 22, 2012 Cheers Daz, So like a lens hood for a camera - looks like something I could make! I take there is no calculation for the perfect length? Just try 6" and see how it goes? Link to comment Share on other sites More sharing options...
BAZ Posted November 22, 2012 Share Posted November 22, 2012 If you had good view's to start with, there isn't much wrong with the collimation. I reckon the dew fairies afflicted your secondary mirror. If it happens again, take out the eyepiece, and shine a torch down the tube, then have a look through the focuser opening. You will see any dew that has formed. The Decathlon dew shields work very well. Make it's length about twice the diameter of the opening, this will allow for fixing it on the tube, and give you about one and a half times the aperture. This should keep the dew out for a good while. I think that when you get to some where with dark skies, your scope will perform very well, and may surprise you. Of course, don't blame us when you get aperture fever. (Looks like you may already have it). Link to comment Share on other sites More sharing options...
Guest Simes Posted November 22, 2012 Share Posted November 22, 2012 Cheers Baz... I'm a bloke - new toys are our life-blood! Link to comment Share on other sites More sharing options...
Brantuk Posted November 22, 2012 Share Posted November 22, 2012 Hi Simes and welcome to EMS Bring your scope to a meeting sometime and we'll help get you going with it - I had around 130x to 150x out of the 130P I had for a while. But the view did depend heavily on the seeing as mentioned above. Good to have you on board Link to comment Share on other sites More sharing options...
Cazz Posted November 23, 2012 Share Posted November 23, 2012 Hi Simes, welcome to EMS :-) I also have a 130p, I can see loads in it - after it's been found for me lol. It's a good friendly size to learn the ropes with. :-) Link to comment Share on other sites More sharing options...
T A WOW Posted November 23, 2012 Share Posted November 23, 2012 here is a pic of my scope and its dew shield. for size ref . Link to comment Share on other sites More sharing options...
Guest Simes Posted November 25, 2012 Share Posted November 25, 2012 Thanks for the pics. Link to comment Share on other sites More sharing options...
cosmic dave Posted November 25, 2012 Share Posted November 25, 2012 Morning everyone, Just after a bit of advice, after the second time of using my new scope - it's all new to me, so be gentle with me! The Scope is a Celestron Astro-master 130eq with motor drive - I know it's not really a class act, but it was inexpensive and an early Christmas present from 'er indoors - and will hopefully be good enough for me to decide if star watching holds the same pleasure now as it did when I was a little chap of 10, when I had a 60X60 refractor and spent night after night watching the moon, and drawing maps of it... Scroll on 40 years and we arrive at last night. I had a play on Sunday night with the scope, but last night start nice and clear and I had fewer other distractions! I set up in the garden - early doors the moon was nice and clear, and then of course, Jupiter dominated the sky. I live on a junction on a modern estate that is over blessed with street lights - one that shines over the garden fence and is so bright you can read a newspaper in the garden at night, and one slightly further down the road that is almost due south - so my viewing is limited with lampposts to the east and south, trees to the north and the house to the west! Earlier in the evening Jupiter was looking good, with 3 moons easily visible and one more just peeping out from the disc of Jupiter, that one disappeared later, not sure if it had gone behind Jupiter or if the seeing had just got a bit worse. I do have a question though (if I may) - using the supplied 20mm eyepiece I could discern bands on Jupiter (that gives me a magnification of about 32X), and I think I could discern them through my new eyepiece (6.5mm Plossl Meade 4000) which gives me 100X. One both Jupiter was a sharp disc and the moons sharp points of light. But later in the evening the 100X was just giving a blurred image - the edges of Jupiter were no longer sharp. On the 20mm it still looked OK though. Was this because the 'seeing' deteriorated or because the scope/eyepiece are rubbish - or a combination of the two! I am not sure about the collimation of the scope - I /think/ it's OK - a star defocussed when in the centre of the view stays symmetrical around the shadows of the secondary and the spider... As you can tell, I don't really know what I'm on about, so all and any help is gratefully received! Was it a tasco 60mm frac ? That's what I started with.. Link to comment Share on other sites More sharing options...
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