Ruined an eyepiece.

[tehmac]

So furious with myself. My new (second hand setup) of 200PDS with HEQ5 Mount was getting a thorough clean by me tonight. I was cleaning the eyepieces, and I got to the last one, a big Skywatcher SWA 38mm 70 degree FOV, and started to clean. I unscrewed one thing too many and before I knew it, multiple glass layers went moving (I didn't realise this would happen, or that it had 5 bloomin' layers to it!) and upon trying to reseat them and screw things back in, I cracked one of the thick layers of glass in the middle. Needless to say, many expletives were used. I then, being a complete novice to all this, looked up the value of it and discovered it was £100. Unbelievable. 

Just needed somewhere to vent.

[Knighty2112]

Yikes! Not good!  

[tehmac]

And I hadn't even used the thing yet, nor the telescope. 

[michael.h.f.wilkinson]

Ouch! Sorry to hear of your misadventure!

[rockystar]

ouch indeed. Have you tried emailing skywatcher? They may have a repair service. I do hear on here, some good things about after sales service of telescope equipment - mainly TeleVue, I must admit, but you never know.

[Charic]

1 hour ago, tehmac said:

 I unscrewed one thing too many and.............

Whatever/whenever the need to unscrew? always film the sequence in order to refit the correct way!  Might even be of help to others too, should their EP's fall apart?
I would take a look too, if I felt the need, part of just being inquisitive, and a better understanding of the parts, but always be cautious, as  most EPs are assembled, I assume,  under strict controls  with gloved fingers?

And £100 to repair a single glass, or whole  EP replacement?.......I'd settle for this one at the lower price..........http://www.365astronomy.com/SkyWatcher-PanaView-SWA-70-deg-38mm-2-inch-Eyepiece.html

[tehmac]

Thanks all. I have contacted Skywatcher, so I will see what they say. With an eyepiece as large as that one, what is the primary use? From the FOV tester websites showing me a glimpse of what I might see through such an eyepiece, it looks like you might as well be looking with the naked eye as it is only around 26x magnification at 1000m focal length and only 46x still with a barlow. Again, I'm inexperienced and couldn't use the darn thing before I broke it, so I'd appreciate your thoughts.

[Stu]

29 minutes ago, tehmac said:

Thanks all. I have contacted Skywatcher, so I will see what they say. With an eyepiece as large as that one, what is the primary use? From the FOV tester websites showing me a glimpse of what I might see through such an eyepiece, it looks like you might as well be looking with the naked eye as it is only around 26x magnification at 1000m focal length and only 46x still with a barlow. Again, I'm inexperienced and couldn't use the darn thing before I broke it, so I'd appreciate your thoughts.

Plenty of use for low power eyepieces; you'll be amazed how different x26 is vs naked eye observing, even x2 or x3 can show you many more stars.

Some objects, or combinations of objects are pretty big, several degrees across. Your ex eyepiece had a field of view of 2.7 degrees in the 200P, trouble is the exit pupil, which is the size of the beam of light hitting your eye would be 7.7mm which is larger than most people's dark adapted pupil. This means you are wasting some aperture, plus there is a risk of seeing the secondary shadow though probably not. The biggest problem is that the sky background will appear quite washed out unless you are under pretty dark skies.

You might find something around a 30mm 82 degree eyepiece would work better, giving a 6mm exit pupil, x33 and a 2.48 degree field of view.

This is an example of what you can fit in a 2.7 degree field, M8, M20 and M21

[Timebandit]

Hello and welcome to SGL. Sorry to hear about your experience and maybe this post may help others tempted to fiddle with eyepieces. Go careful and make notes as you go along.  And unless the eyepieces really needs cleaning then maybe it's better left alone"if it's not broken then don't fix it" approach. I do hope skywatcher can help you.

In regards to low magnification, wide field eyepieces and their use. It is surprising if you look at the night sky with your naked eye ,and then look at the same location of sky with a low magnification eyepiece such as yours the amount of numerous extra targets like stars that come into view. It has surprised me in the past how usful these low power eyepieces are for opening up the sky's, compared to just the naked eye. They also make great finders , if you are looking for a target in the sky's and not quite sure where it is , these wider field eyepieces can help you located before you go up the magnifications for a closer look. I used to think magnification was everything but you begin to learn low power magnification with wider field of view can open up vast sections of the sky's,       to give you  more of a space  walk experience.

I hope this helps☺

[Davesellars]

Ouch.  Sorry about that.  Eyepieces (generally) aren't meant to be unscrewed (as you now know...).  Will be interesting to hear what Skywatcher come back with re-service.

However... A 38mm EP in a 200mm f/5 reflector is somewhat pointless.  The exit pupil is 7.7mm - way past the the point where you'll be seeing the central obstruction.  A 25mm EP giving 5mm exit pupil should be the maximum but you may be able to get away with a touch more.

[acey]

Bad luck, put it down to experience. Now you know you'll never make that mistake on an Ethos. The warning for other novices:

If it ain't bust don't fix it, and if it ain't dirty don't clean it. The novice definition of "dirty" is "not looking like brand new". Expert definition is "views are noticeably affected". Observe first, start fiddling once you know what you're doing and why.

Apologies to OP who knows that already.

 

[Charic]

I missed the fact that your using the  38mm ( I was tired, and even my texts were duplicated 11 hours ago ( Thanks Mod for correcting) The  link I supplied was  a like-for-like replacement, but as already mentioned above a 38mm may be  too much for you depending on your pupil size?

Take the telescopes focal ratio and multiply that by your known or guesstimated pupil size. so for example , a 6mm eye-pupil would warrant a 30mm eyepiece, just a guideline, but do not exceed too far from the numbers obtained when using a reflector scope!
All very well having a 38mm  providing the brightest and widest exit pupil, but if your entry pupil is smaller than the exit pupil your eye cannot take in the whole width of the exit pupil ( that beam of light, the Exit Pupil is 7.14mm from a pair of 7x50 Binoculars! If your pupil size is 6mm then using the same binocular, your eye, only accepting 6mm of exit pupil, you may as well have bought a cheaper binocular of say 7x42, because  42/7=6, so although your still holding a pair of 7x50's, the effect of having a smaller eye pupil is that your now using a virtual 7x42 binocular? - sorry if a little puzzling - therefore you waste the extra light afforded, , its unusable! I should be using about 30mm but I own the 32mm, the one in the middle of the  SW set, closest to my needs, and it works well for me.

As for their worth,  for deep sky objects, I always work with my lowest powered eye-piece first, working my way up to the highest, or the highest allowable under my conditions, until the scope has cooled to ambient temperature, giving me the sharpest, in-focus,  framed image, this then  becomes the eyepiece to use, depending on the subject.

M31 is so bright and so huge, try looking at it at high power from a street-lit back garden? Is it worth it you ask?  you may just see a smudge faint wispy, a blur!  but take another look from a dark site, no street lighting, and looking through the low-powered wide-angle eyepiece,  M31 is stunning,  filling the eyepiece, and should astound you! and not only that,  your still using the same telescope! All to often, folk think, high power is what they need, where as a Newtonian's image will always look sharper, crisper, cleaner although a tad smaller using  a lower focal length eyepiece,  which Is why I have several eyepieces to allow me the option to focus and frame properly.

Lastly, if any owns any eyepieces that are guaranteed fog free, binoculars too, do not open them, the inert gas will be released, and you will have no way of recharging the system!

 

[F15Rules]

Some good advice above, but cold comfort when you are still kicking yourself after the initial "disaster" (been there, done that !).

Assuming you still want a replacement, here are a couple of options that should work well for you, at lower than £100 cost...(and of course if you check on the For Sale and Wanted forum here, or on UKAstrobuysell, they do come up used in good condition from time to time...

http://www.bresser.de/en/Sale/Display-Items/Meade-Serie-5000-Super-Wide-Angle-Eyepiece-28mm.html - this is a superb eyepiece, much better than your original Skywatcher, and a bargain at this price. I have bought a few items from Bresser Germany with no issues at all. Shipping to the UK will add around £8-£10 to the cost. The 28mm focal length and 68 degree field will show you some wonderful low power views in your scope.

http://www.bresser.de/en/Sale/Display-Items/Meade-Serie-5000-Super-Wide-Angle-Eyepiece-34mm.html - even better than the above 28mm in my opinion, I have the Explore Scientific version (optics are the same) and it is just superb. 34mm focal length giving you around x30, perfect for amazing low power views. Another bargain although close to your £100 cost of the original, these were well over £200 when new.

Hope this helps and good luck with getting your replacement - either of the above will outperform your original :-)

Dave

 

[BGazing]

ouch. 

but on a bright side, you now have an excuse to start browsing the forum and the websites for the best replacement.

[Louis D]

On 7/15/2016 at 16:46, tehmac said:

I was cleaning the eyepieces

Yeah, best to just give the eye lens a light wipe with a clean microfiber cloth every once in a while to remove gunk.  Turn it upside down over your mouth and lightly huff upward onto it to give it a little distilled moisture from your breath while avoiding spitting on it.  You should rarely, if ever, need to clean the field lens.  Unless the focal plane (field stop) lies very near to it, you'll probably never notice dust on it.  Inner surfaces should be good for life unless something like liquids or fungus get in there.  That said, I have received eyepieces and camera lenses that sat around a long time in polluted environments uncapped, and there was a fine layer of haze on the outer lenses that needed to be cleaned off, but that's a whole 'nother story.

[Dave In Vermont]

Up 'round my 'neck-O-the-woods' we have a saying that fits the underlying message of this thread - imho - and it's: "If it t'aint broke, DON'T fix it."

This has been found, on many instances, to be especially true for us when we approach 'cleaning our optical-goods.' I've been using telescopes and eyepieces for over 40 years, and I approach such cleaning with fear & trepidation. Any questions I may ask myself regards 'Why?' - these tales of woe act as a healthy reinforcment towards said.

I'm sorry to hear of your problem, tehmac. May it serve us all well.

Dave

[spaceboy]

That's hard luck Tehmac but these things are sent to test us. As others have said though it really wouldn't have offered much in your scope due to the exit pupil. Still useable none the less but not to it's best of abilities. That's not to say you couldn't have sold the eyepiece on for £50-£60 pound and got an alternative eyepiece more suitable. As the saying goes "if it ain't broke don't fix it" but I can totally relate to where you are coming from. It is all part of the fun for me to give new to me kit a once over even when it doesn't need a clean over I feel an impulse to do so.