theironduck Posted April 21, 2013 Share Posted April 21, 2013 I got my first view of the moon last night - fantastic! I wanted to have a closer look at some features on the limb so used my 10mm BCO EP with my 1.3x Baader Classic Barlow on my Celestron 5SE (5" SCT). Here's what I saw (handheld iPhone):As you can see, in the middle of the FOV there's a bright ring which is some sort of artifact (coming from the central obstruction?). A similar artifact is also observable with the 10mm on its own but to a lesser extent. Any ideas what's causing this and how to fix it? It's a bit annoying for visual observations, although I can work around it, but will mean I can't use these EPs if I want to try my hand at astrophotography.Thanks! Link to comment Share on other sites More sharing options...
Astrobits Posted April 21, 2013 Share Posted April 21, 2013 In your image the edge of the FOV can be seen to the top left and the defect is not in the centre of that circle. It appears to be central, approx, to the moon. Have you tried checking that there is no dirt/dust in the eyepiece itself, rotate the eyepiece when viewing the moon - does the artifact move or stay in the same place? Check that it is not a reflection from your eyeball/camera lens, move them around and in/out.I cant think of anything else at the moment, perhaps someone else in SGL has a better idea on this one.Further investigation is needed.If all else fails go along to the Bristol Astronomical Society ( I think they will be your nearest ) or contact me and we can try to sort it out ( I'm in Highbridge so not too far from you in North Somerset).Nigel Link to comment Share on other sites More sharing options...
theironduck Posted April 21, 2013 Author Share Posted April 21, 2013 Hi Nigel, thanks for your suggestions. I was rather hoping this was an easily diagnosable noobie error (but secretly fearing it was a problem with my scope) but as no one could identify the problem straight away I was becoming rather puzzled. I've now found the source of the problem - it's nothing to do with the design of the SCT, the use of the barlow or the collimation. A close up examination of the 10mm BCO showed the following:There appears to be a bubble or circular crack in the optics of the 10mm BCO. It's a bit of relief to have an answer bit I do feel a bit of a fool for not spotting the cause earlier. I shall be contacting FLO in the morning to try to get it replaced. Link to comment Share on other sites More sharing options...
John Posted April 21, 2013 Share Posted April 21, 2013 Wow thats quite a flaw - I'm sure FLO will be quick to replace that one for you.I can't recall seeing anything like that in an eyepiece before.At least you know what the issue is now, and it's not your scope Link to comment Share on other sites More sharing options...
LukeSkywatcher Posted April 21, 2013 Share Posted April 21, 2013 My first thought was that it was a focusing issue (using a 10mm EP and a barlow in a 5 SCT.........which should work) causing a ghost reflection of the central obstruction. The fact that you still see it (to a lesser degree) with a 10mm EP alone has me puzzled. Does it appear visually when looking through the scope or just when you attach a camera? Link to comment Share on other sites More sharing options...
Stargazer_00 Posted April 21, 2013 Share Posted April 21, 2013 that's a rare flaw indeed id imagine. is it on the underside or the topside, or even rarer in between the elements? Link to comment Share on other sites More sharing options...
theironduck Posted April 21, 2013 Author Share Posted April 21, 2013 John, well it's nice to be special but it will be even nicer to have a functioning EP! I'm quite looking forward to having another pop at Jupiter with the replacement 10mm when this cloud disappears again.(Btw, thanks for your helpful suggestions on the other similarly named thread). Link to comment Share on other sites More sharing options...
theironduck Posted April 21, 2013 Author Share Posted April 21, 2013 It's a bit hard to gauge the depth of the fault but it's definitely not on the outside of the lens and it's closer to the front (eye end) than the back I reckon - so somewhere internal. It's not that easy to spot with the naked eye although you can just make out a small ring dead centre when you look down the lens at a light background. I'd be interested to hear what FLO or Baader had to say about it. Link to comment Share on other sites More sharing options...
Stargazer_00 Posted April 21, 2013 Share Posted April 21, 2013 I expect FLO will apologise profusely and immediately replace it.I wouldn't expect anything at all from Baader Link to comment Share on other sites More sharing options...
theironduck Posted April 21, 2013 Author Share Posted April 21, 2013 Hahaha... Link to comment Share on other sites More sharing options...
E621Keith Posted April 21, 2013 Share Posted April 21, 2013 That's quite a serious defect, especially if the crack is inside the eyepiece. Defiantly get it replaced. This defect is quite easy to spot, so I'm surprised it wasn't spotted in QC. It makes me worried if BCO goes through any quality control check before leaving the factory. Link to comment Share on other sites More sharing options...
theironduck Posted April 21, 2013 Author Share Posted April 21, 2013 I'm not sure if it's a crack or a bubble. The EP came to me very well packaged from FLO and the problem was evident straight out of the box (I just assumed it was something to do with the SCT geometry rather than the lens) but I guess something could have happened between Baader and FLO. OTOH, the defect could be a bubble - the central region can be focussed, acting as a mini lens-within-a-lens. Link to comment Share on other sites More sharing options...
theironduck Posted April 21, 2013 Author Share Posted April 21, 2013 So, a happy ending... FLO just got back to me (at 10.45 on a Sunday evening - that's first class customer service for you) and offered to upgrade the BCO to a Hutech Ortho (£89). Now, which one to choose, 5, 6, 7 or 9mm? My 25mm Celestron Plossl can be barlowed to c.11mm so perhaps the 7mm for some variety? Any thoughts anyone? Link to comment Share on other sites More sharing options...
John Posted April 21, 2013 Share Posted April 21, 2013 Thats a great offer from FLO and on a Sunday evening too The 7mm would give you 179x which would be useful on Saturn and the Moon when your scope is cooled and the conditions are good. The focal lengths beneath that will have eye relief that some folks will find quite "tight". Thats a feature of the orthoscopic design, not just the Hutech ones.You should be able to use the optical element of the barlow with the 7mm to get 5.4mm - I've done this with the Baader Genuine Orthos and it works pretty well so no reason why it should not work well with the Hutech ortho as far as I can see. 5.4mm will really max out your scope at 231x.So, yes, the 7mm does seem a good choice. Link to comment Share on other sites More sharing options...
Astrobits Posted April 22, 2013 Share Posted April 22, 2013 That was a bad flaw. I am surprised, as others were, that it got through QC. However, we rarely hear of faulty eyepieces so the odd one has to get through sometimes.Brilliant FLO response, Must buy some faulty stuff from them sometime :grin: Nigel Link to comment Share on other sites More sharing options...
theironduck Posted April 22, 2013 Author Share Posted April 22, 2013 I'm secretly hoping the Hutech EP is duff - a few more (about 30) trade-ins and I'll be able to afford the Hubble telescope in the Offers section... Link to comment Share on other sites More sharing options...
michael.h.f.wilkinson Posted April 22, 2013 Share Posted April 22, 2013 Never seen anything like that. Good that you are getting a replacement. I would indeed go for the 7mm shorter ones will see little use. Link to comment Share on other sites More sharing options...
Stargazer_00 Posted April 22, 2013 Share Posted April 22, 2013 I know you were joking but I wouldn't hope for a duff. Bad karma. Link to comment Share on other sites More sharing options...
theironduck Posted April 22, 2013 Author Share Posted April 22, 2013 Don't worry, the inevitable 3 weeks of clouds when it arrives will pay my karma bill... Link to comment Share on other sites More sharing options...
theironduck Posted April 23, 2013 Author Share Posted April 23, 2013 So, I've opted for the 7mm HuTech and FLO say it'll be despatched today. My sincerest apologies to anyone in the SW who hoped to see the sky again this month. Link to comment Share on other sites More sharing options...
alan potts Posted April 23, 2013 Share Posted April 23, 2013 Makes you wonder if the QA of these new BCO's is up their with the BGO's as they once were. However even the best companies can let a mistake slip through it's production process, it in nice to read the response from First Light, top draw.Alan Link to comment Share on other sites More sharing options...
theironduck Posted April 27, 2013 Author Share Posted April 27, 2013 My new HuTech 7mm came from FLO yesterday. It is a very solid piece of work - you could probably hurt yourself if you dropped it on your toes! The body is chromed with a black top. I think I prefer the matt black look if the BCOs but the HuTech wins on heft. There's no rubber cup on the 7mm which suits me. Eye relief seems OK but I don't have much to compare it to.I got a chance to use it last night. Happily it is nearly parfocal with my 25mm Plossl + Barlow which is handy for planetary stuff. The seeing was awful last night - I could actually see Jupiter shimmering - but the view through the 7mm was good. I am really looking forward to using it on a clearer night, especially when the moon and Saturn are visible at a sensible hour. Link to comment Share on other sites More sharing options...
John Posted April 27, 2013 Share Posted April 27, 2013 The seeing here was poor last night - I was comparing the Hutech's with the Baader Genuine and Classic orthos, or rather trying to On the quality control of the Baaders, I have a Baader GO 7mm at the moment with, what I think is, touching lens elements. This causes a circular area right in the centre of the field of view to be unsharp when the rest of the field is razor sharp. The eyepiece was lent to me for review purposes and I think is a new one so errors do occur on all ranges from time to time.For what it's worth, physically the Baader GO 7mm looks exactly the same as the Hutech 7mm apart from the branding. Even the lens coatings seem to match exactly. Link to comment Share on other sites More sharing options...
theironduck Posted April 28, 2013 Author Share Posted April 28, 2013 Better luck last night? The sky looked clear. I would've had a crack myself but my wife and I had a rare evening out (in Brizzle). Link to comment Share on other sites More sharing options...
Stargazer_00 Posted April 28, 2013 Share Posted April 28, 2013 shimmering haze again Link to comment Share on other sites More sharing options...
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