Meade 5000 ED 127mm Triplet F7.5 Refractor Long Term Review Phil Jaworek

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1 Meade 5000 ED 127mm Triplet F7.5 Refractor Long Term Review Phil Jaworek Introduction My astronomy had changed over the 5 years that I owned a Celestron C11 SCT. In the early days I was a visual only astronomer where aperture is king and the C11 was easily up to the job. During the period of ownership however I started imaging and soon found imaging with smaller and faster scopes much easier than with the C11. Pretty soon the C11 was left in the cupboard and did not get the use it deserved. In 2009 I finally made the difficult decision to change the C11 for a refractor big enough to do justice to DSOs for visual work; good enough optically for imaging; have adequate focal length to provide decent image scale on galaxies and planetary nebulae but more importantly, possess a price that wouldn t break the bank. Thus in July of 2009 after a great leap of faith, (due to lack of reviews), I purchased a Meade ED Triplet F7.5 Apo Refractor and sold the C11. Specifications This being a long term review I have deliberately left out 1 st impressions and 1 st lights preferring to concentrate on what the scope is like after 2 years but for the sake of completeness I have included specifications and a brief description. Extract from the Meade Web Site: The Meade 127 EDT in visual mode on HEQ5 at SGL6 Optical Design: 3-element Apochromatic Refractor Objective Lens Size: 127mm (5") Focal Length, Focal Ratio: 952.5mm f/7.5 Optics: Fully Multi-Coated Telescope Dimensions ((L x W x H): 33.3" x 6.125" x 6.125" Tube Body: Aluminum Dew Shield: Built-in Extendable Optical Glass: FCD1 ED (Extremely Low Dispersion) glass. Air spaced in lens cell. Focuser: Machined 2" Dual Speed Crayford style focuser Diagonal: Series " Enhanced Diagonal Telescope Weight (with diagonal): 17.7 lbs. PJ addition: Internal Baffles 3 Typical Price inc case and 2 diagonal Typical Price inc case and 2 diagonal

2 Brief description OTA is gloss white and is complete with a fixed Crayford style dual speed focuser finished in black high gloss anodising. The draw tube is graduated with a white millimetre scale and provides approximately 4 of travel. A finder bracket is fitted to the focuser body by means of a blue anodised rotating ring allowing the finder to be rotated to achieve a comfortable viewing position. The gloss white 8x50 straight through finder is fitted with a graduated reticule. The reticule is illuminated by a red LED powered by a button cell. Illumination intensity is adjustable. A 6 long retractable Dew Shield is finished with an anodised blue locking ring, colour matching the finder ring. A turned aluminium dust cap screws into the end of the dew shield to provide objective lens protection. The unusual rotatable finder bracket. Also shown is the illuminated reticule finder, a nice touch. 2 cast aluminium tube rings are supplied, fitted with a cast carry handle and a cast Vixen/Synta fitting dovetail bar. The carry handle has a ¼ wide axial slot providing a handy fixing point for accessories such as camera brackets etc. The dovetail bar is only beveled for a short length therefore it may not fit all mounts. Rings, handle and dovetail are painted with a black satin finish. Mechanics Finish. The gloss white paint finish is quite rugged and is good for a scope in this price bracket. There were a couple of minor cosmetic blemishes when new but hey this was a 5 Apo at just over a 1200 so I reckon these can be forgiven. Generally the fit and finish are good and perfectly functional, in 2 years the paintwork has acquired only a couple of small nicks despite being used at star parties and in the field. The interior of the dew shield is painted matt black but there were a couple of smudges of white paint to be seen as if someone had handled the dew shield before the top coat had cured. This was easily solved with a small brush and a tin of matt black paint. The dew shield is prevented from slipping fully down the tube by a large internal spring clip, this has started to show signs of rust after 2 years of dew laden nights; again this was easy to remedy and can be removed for repainting easily.

3 Focuser The gloss anodised finish looks good and has proved as rugged as the paintwork, after 2 years it still looked as good as new. Unfortunately the draw tube is developing the inevitable tram lines from the Crayford bearings. This may be due to my adjusting the grip of the focuser a little too much to avoid slippage when I fit my camera and filter wheel. But even with the tram lines the focuser still works smoothly. The focuser is excellent for visual work the two speed adjustment is handy for teasing out fine planetary detail and has a positive feel. The focus lock works well ensuring the draw tube does not shift even with a large load on the back, however there is a tendency for the focus to shift slightly when locking. Now this isn t too much of a problem when visual observing but I did have some frustrating moments during imaging, eventually opting not to use the lock at all. The focuser and finder bracket. Tramlines on draw tube are typical of this type of focuser but do not affect performance The only thing I would change about the focuser is to make it rotatable to allow image framing with a camera without focus shift. Unfortunately my Revelation binoviewers would only reach focus when barlowed but this was easily solved by adding a couple of longer fl eyepieces to my eyepiece case. Finder & Bracket The finder fits onto the focuser assembly with a very novel bracket. Because the focuser does not rotate the manufacturer gets round this by fitting a rotating ring to the focuser on which the finder bracket is screwed. Thus the finder can be moved by loosening a single lock screw on the focuser ring, rotated to a more accessible position and then locked. This is an unusual but perfectly functional system. Optics Lens & Cell The three element objective has a fine green tint indicative of the coatings used. There are no push pull collimation screws, therefore collimation is factory set and cannot be adjusted. Despite 2 years of use and the inevitable transportation knocks, star tests and occasional checks with a Cheshire eyepiece reveal the collimation is still spot on. CA For visual work the lack of colour is exceptional for a scope in this price range, the lunar limb shows no fringing and planetary detail is clear, contrasty and sharp even at high magnifications. The business end showing the green coating tint. 2 of the 3 internal baffles are clearly visible

4 I may be too picky here but I think with very long exposure images there is a very slight blue tint detectable to brighter stars but the stars are not bloated in any way. This is no real problem because a quick tweak in photoshop using Noels actions or colour balance sorts the star colours easily. My modifications over the 2 years of ownership Most new owners will want to change the supplied dovetail bar straight away because the mounting area is too short for some mounts, the HEQ6 for one. I have 2 dovetail bars which I swap depending on what mount I am using, CGE spec for my observatory mount and a standard 8 Vixen style bar for my HEQ5 mount. I have replaced the carry handle with a length of ADM mini dovetail bar. This still provides a convenient handle but provides a quick connection fitting for my guidescope. After seeing and testing a Moonlite Focuser on someone else s scope I knew then I just had to have one, I was smitten, ADM MDT rail doubles as handle and guidescope mount so in January 2011 I gave into temptation and bought the large format version for this scope. The Moonlite is rotatable and has a non image shift focus lock so as well as looking superb in anodised blue to match the Meade trim it sorts the little quirks of the stock focuser. Don t get me wrong here, the stock focuser is well designed and functional and should last a lifetime for visual use but I crumbled and treated myself to a little luxury which has turned a good scope into a superb scope. The finder is occasionally swapped for a SW 9x50 finder home modified to right angle viewing. This little modification helps with any scope and saves bending and backache when trying to locate objects near the zenith. Performance Cool Down Cool down time is quite short but does benefit from a ½ hour or so to acclimate and get the best views. Lunar and Planetary Visual This scope excels on lunar, the 5 aperture gives plenty of resolution and the image brightness enables very high magnifications (400x and above) to be used when seeing conditions allow. I regularly use planetary filters to tease out fainter detail, because of the bright image, these can be used easily without loss of definition on lunar and the brighter planets, Mars, Jupiter and Saturn particularly. My C11 had the aperture advantage and image scale wow factor but the unobstructed view through the Meade has the edge on contrast I reckon. A good example of this is recently we had some non-astro friends around for an evening meal. The night was clear with a glorious 1 st quarter moon and Jupiter riding bright and high. Our guests expressed an interest in looking through my scope and so without hesitation I set up the Meade and showed them the moon. They were enthralled but then I turned the scope to Jupiter and slotted in a TMB 6mm planetary eyepiece (158x). I then asked them to describe what they could see. Each said they could see stripes and a large blob, (belts and the GRS) but then after a few seconds there was an exclamation as they found the sharp and clear black dot of an IO shadow transit.

5 Testament to good optics I think when beginners can spot detail like that after a few seconds at the eyepiece. TMB planetary eyepieces work very well in this scope but my favourite is the Meade mm eyepiece, this is just that bit clearer and of course has a wider true field of view. Imaging I do enjoy using the scope with my Canon 1000D for taking full frame lunar shots, the focuser holds the camera securely and the fine focus control enables easy focusing using the cameras live preview mode. I have also been known to use my QHY5 ccd guide camera to take more detailed shots of the moon with or without barlow lens to good effect. I must admit to not ever having tried imaging any planets with this scope. I tried web cam planetary imaging when I had the C11 but never really took to it because of an acute lack of patience when it comes to processing. This will certainly change in the near future. Deep Sky Visual This is where I thought I would miss the aperture of the C11 but the Meade has performed well, the 5 aperture gives plenty of light grasp and still pulls in the fainter detail. For example the C11 could pull in the Veil Nebula unfiltered but I can still detect the brighter regions unaided on a good night with the Meade; filtered there are no problems and its easily seen. Globulars are spectacular in this scope, the sharpness of M13 is something to behold. Obviously the image is not as bright as with the C11 but a good eyepiece, and a comfortable observing position will tease out thousands of stars resolving the core beautifully. Over the years I have learnt the correct way to observe; take your time and look properly at the object and you will be amased at what you ve been missing with quick glances at objects. Nebula The view of M42 is a show stopper in any decent scope and in the Meade it s the same but slotting a Hbeta filter in the view reveals loads of detail, fainter outer swathes of the nebula pop into view and I can spend hours on this object alone. Galaxies and fainter stuff I used to use the C11 for spring galaxy bagging with a Mintron video camera to see how many faint and obscure galaxies I could find; I am pleased to say I can still do the same with the Meade. I took the Meade and Mintron combo to a recent star party (SGL6) to do the just this and I must say I was not disappointed. Over 2 clear nights I lost count of the number of galaxies I caught in the Virgo and Coma regions. I understand this set up was giving the equivalent to what could be seen with the unaided eye in a 16 Dobsonian. Not bad for a 5 scope eh? Double/Multiple Stars Since going refractor I have discovered the pleasure to be had from double star observation. Through the Meade in-focus star images are perfect little bulls eyes indicative of well corrected optics. If truth be told my favourite double star scope is a 30 year old 4 F15 achromatic refractor but the Meade is quickly becoming a firm favourite, the extra 1 of aperture helps when resolving very close doubles. The Trapezium is easily split with the E&F stars visible with medium magnifications. Porrima which is now starting to open up shows dark sky between the components at 200x. Epsilon Lyra splits into 4 components under 100x and the excellent colour correction makes identifying component colours easy, Albireo and Izar for example.

6 Imaging This scope is easy! It is so well behaved compared to my old C11. With the Meade one can concentrate on imaging and not worry about initial focus, focus drift due to temperature or even dewing because the long dew shield keeps this at bay in all but the wettest of nights. With a DSLR or CCD camera focusing is very simple. The graduated draw tube aids setting the approximate focus point then the smooth and positive fine focus control comes into its own. I use a Bhartinov mask for CCD focusing and a STI Stiletto focuser with the DSLR and can honestly say I have never had any trouble achieving focus. Once focus is achieved I no longer lock the draw tube as this shifts the focus slightly. With the focuser tension set to a firm position the friction in the focuser is enough to stop focus slip even with a camera and filter wheel fitted and the scope pointed at the zenith. If you are not using a 2 diagonal between the scope and camera you will need a 2 extension tube to achieve focus which is quite common for refractors. The image scale is ideal for the objects I want to capture with this scope. For example M81 takes most of the chip up on an Atik 314L+ whereas both M81 and M82 can just be crammed into the field of view when using a Canon 1000d. M1 in RGB with Atik 314L+. Slight cropping. M81 Luminence channel only. Through Atik 314L+. No cropping

7 Field flatness is very good Initially I used the scope with a Canon 1000D DSLR and did detect a slight coma at the edge of the field of view when imaging at the focal plane. Uncropped full frame M35 taken with Canon 1000d at focal plane, no flattener, showing slight coma in bottom left and right of frame but nothing that cannot be cropped out. Does this scope really need a flattener? IMHO no. I therefore rashly purchased a WO MKIV flattener / reducer which cured what little coma there was completely but at the expense of slowing the F ratio even more. This was because the MKIV I purchased was an early version which flattened but didn t reduce, in fact it actually increased the FL by a small amount. Also the MKIV was big and heavy so much so that with the added weight of the camera the focus would sometimes shift when not locked. For those reasons I think I must have used the MKIV about a dozen times before selling it. Now I just crop the edges of any dslr images to remove small affected areas. Of course with the Atik 314L+ camera field flatness is perfect for the chip size, in fact I often use my WO MKII flattener just to take the F ratio down to around near F6 for some objects, this works only because of the smaller chip in the Atik. Mounting I was going to put this category under mechanics but I think it important enough to warrant a section on its own. At around 9 kilos with a 2 diagonal and a reasonable sized 2 eyepiece this scope is no real heavy weight but the weight and its size at just over 6.25 diameter at the dew shield and 39 long with the dew shield extended makes it quite a handful. Therefore careful consideration must be made to the mount the scope is going to be used with in order to get the best from this scope. For imaging I use my observatory Celestron CGE mount. This is more than big enough to handle the scope plus a 4 guide scope and accessories. I am sure an HEQ6 sized mount would work equally as well but I would not advocate imaging with anything smaller. For visual work I use the scope predominantly on my HEQ5, (see image on page 1), fitted with heavy duty home made ash tripod. This works quite well, the HEQ5 takes the weight easily but the scope does look under-mounted and vibrations take a

8 second or so to damp down. Things can be improved by using a short solid dovetail bar and keeping the scope out of the wind. Conclusion I like this scope for so many reasons Optical quality Excellent optics for the money, you will have to pay a lot more to get optics better than this. Versatility - I can either use it in the observatory for imaging or use it in the field for visual work. Its weight and size mean the scope can be transported and set up easily without straining your back. Plenty of aperture to satisfy the visual observer in me. Crisp contrasty images giving superb lunar and planetary views. So after 2 years of use I reckon this scope is as close to a general purpose scope as I can get. Do I regret swapping my C11 for the Meade as some foretold at the time? No way! Thanks for reading and clear skies. Phil Jaworek 2011