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Found 8 results

  1. Ben the Ignorant

    Oversize clip-on solar filter for dob

    I wouldn't want to miss observing the Sun in a full-size 300mm filter, the detail compared to smaller instruments is such a joy to see. I do have an off-axis mask for my 300mm dob but not all the time. If daytime seeing is too bad for such a large scope, I'll switch to a smaller one, but the extra resolution and ease of spotting micro-detail thanks to the brightness is something I can't do without. A sheet of 500mm wide Baader fillm allowed me to craft this. I had enough left to cut several smaller filters. To protect it I made a storage box from cardboard of obvious origin. The box had to be custom-made to save space in my dwelling, and it also hosts a bahtinov mask for nighttime. At f/5 fine focus is not too hard with the smooth single-speed focuser, but in order to enjoy moments of clarity immediately at high power, I pre-focus with the bahtinov, which sees through turbulence, what a nice invention, and simply wait for calmer air. No need to rush to fine focus and waste precious moments. This mask needs to be copied in some sort of plastic, the cardboard trial proved the number and width of the slits are fine. The rear of the filter shows the four clips mating the four button screw heads outside the tube. And this lateral view shows the sandwiching. A rigid backing plus two layers of lightweight neoprene foam cut from a cheap mat in tiger-stripe deco, its poor taste matching its 7€ price. The bottom sheet used to be a shower booth panel, my neighbor had in its garage. Hey, do you need that? No? Okay, thanks! The Baader film is held between the neoprene sheets by staples and many strips of tape. The neoprene is held to the shower booth sheet by little collars, and its edges are sewn together for a finished look. Oversize 10mm stitches didn't take too long to do, and the foam layers can be separated for replacing the film, something glue would prevent. Holes in the neoprene allow to check that the clips' bolts are always tight. Close-up of a clip. They are made of a material whose name I forgot, I only remember it is made in the UK (thanks, guys!). This is a PVC foam that's much easier to cut, drill and sand than full-density PVC, and it's much lighter (thanks, air bubbles!), which is essential for an item that's at the front of a scope where leverage is maximal. My GSO dob has four of these screw heads, one for each spider vane. They proved very convenient for attaching the filter. The black knob is an add-on to move the scope without having to grab the large tube with both hands. Pretty obvious what we're seeing here. Note the clip is flush with the tube, and pressed hard against the scope's metal rim for a very secure and tight fit. Only four clips but eight attachment points, really. Building this with tight tolerances was more lengthy but more reassuring. It is impossible to disengage a clip by accident because tolerances are too narrow, and the shower booth plastic tough spring action doesn't allow it. But should it happen three clips would hold the filter safely. All three layers of frame material are flexible, so, to remove the filter from the tube you just bend it at a corner while you lift the clip, and the clip disengages. I already rebalanced the dob by pulling the 7-kilo mirror to the rear thanks to shorter and tougher cell springs but I'm working on a sliding counterweight made of pliable steel ribbon. Adhesive felt pads protect the paint. Thanks to the large hole the 300mm filter is not too heavy (and it's used without the finder) but the off-axis mask has only a 115mm hole, so it's heavier and may require this. While I study the combinations of heavy or lightweight eyepieces, finder/no finder, mask, filter, I can change the experimental counterweight by cutting off or adding pieces of steel ribbon. Little mounting nuts and bolts through the many holes, there's always one at the right place. Ever hated to feel the Sun while loving to watch it? If you have no sunshield you did. Heat is a discomfort on the head, and light kills off contrast. So I cut a plastic folder in this weird pattern to allow sliding it between the shower booth plastic and the neoprene mat. When it's stuck there it makes quite a large area of shadow, that's such a relief. But that's also only a prototype that wants to be made again with a better material. Has to be opaque, quite thin, very lightweight, but rigid enough. I'll stumble upon the right material sooner or later.
  2. Hi Guys, I wondered if it's possible to attach a mirrorless camera (that is a camera that is not able to remove it's lens) to a telescope. Is there an attachment or a camera holder? Luminous Thank you, in advance
  3. 21 of June 2017 / 22h30 UTC+01:00 / Stargazing Conditions: 88% So, I crammed all of my new acquired stuff together and went to the darkest place I could find near my town. It's a mere 5 minute drive from my home. As I set everything up, I tried to wait for 20-30 minutes to give the 'scope a chance to acclimatize but I really couldn't! Jupiter I looked west south west to find Jupiter, pointed my finderscope at it and I was amazed by how clear the image from the 'scope was!! I had a 5 minute stare through my 25mm BST eyepiece where I could distinctly see the two belts, the north and south equatorial belt. As clearly as the belts were also three of its moons were, namely Callisto, Europa and Io, although Europa was quite close to Jupiter. The color was also great and the view, simply mesmerizing! I then switched to the 15mm BST eyepiece. First I was a little, let's say disappointed, but not that strong, by the magnification, and immediatly switched to the 8mm BST. To my surprise I wasn't convinced by the view either... So I decided to get back to the 25mm and calm down and enjoy the view as I clearly was getting hasty. As I started over, I remembered some words from a friend of mine who told me that watching the stars often comes down to 50% of actually seeing the stars and 50% imagination and concentration. So I tried the 15mm a second time and... I was hooked. I could now clearly see eight different colors and belts! I'm not quite sure what it was I saw, except the north and south equatorial belt, but I will have a look at some Jupiter maps and educate myself about the planet's surface. This will help in better understanding and watching next time, the case given that the seeing is as clear as it was that night. With the 15mm eyepiece Europa was now very distinct from Jupiter. I couldn't manage to get more detail out of the 8mm eyepiece, everything just got a tad bigger and a little fainter if my impressions were right. After good half an hour of watching the delightful planet and its moons I sat down and searched for Saturn, which was south not very high above the horizon. Saturn I switched back to the 25mm eyepiece, pointed my viewfinder at Saturn and peaked through the eyepiece. What a marvel! I clearly could see some colors on the surface and easily distinct the ring from the planet itself. As I switched over to the 15mm eyepiece, the separations on the planet's surface became a tad clearer and the ring/planet separation obviously bigger. I encountered the same problem as before of not knowing what I was looking at, which bothered me a little. I have to do a little homework here and get myself started with some fancy vocabulary. Milky Way All in all it was a marvelous first light experience and I clearly have to learn the stuff I'm looking at, but I think that's just me and my endless thirst for knowing things. I randomly gazed through the skies at the end, beeing absolutely overwhelmed by everything I saw. Furthermore, I simply was flabbergasted when I ran across the milky way in the north east... There were so many stars I couldn't see with my bare eye, but only with the 'scope (which made aiming with the finderscope a nightmare... How do you guys do that really?!). I'm glad I acquired the Skywatcher Skyliner 200P with the eyepieces. It is one of the best things I got myself and I think I will have a lot of fun with it and furthermore learn so many new things. Thanks for reading, Abe
  4. 3rd of July 2017 / 21h30 UTC+01:00 / Stargazing Conditions: 80% After much reading and hyping myself so much, I was pretty stunned by the early notification on my phone that yesterday night could potentially be a good evening with good seeing. So I went home after work (with my phone still showing 80% of potential seeing), sat on my desk and prepared myself. I chose to watch the Moon, since I never really observed it, Jupiter, Saturn and search for the Sombrero Galaxy! Last week I searched for a few good atlases and stumbled unto the Interstellarum Deep Sky Atlas. A promising atlas which should arrive this week, but still would let me be without a field atlas, since it is a desk edition... After cramming in the forums I mainly found three downloadable recommendations: 1) The Deep-Sky Atlas 2) Deep-Sky Hunter Atlas 3) TriAtlas I downloaded all of them and browsed through them, noticing that only the Deep-Sky Hunter Atlas exists in a field edition. I printed the normal Version on A3 paper to look if it fits the need and, hell yeah, I really like it so far!! Only downside (for me) at the moment, is that the constellations are in black lines in contrary to the Deep-Sky Atlas. So I think I'll print both of them, laminate them and take them with me on my sessions. (I will have to inverse the colors on the Deep-Sky Atlas though) To round everything up, I figured that I'll need a software too, to plan my sessions a little better and just give me the right impressions on where I will have to search in the sky. A while back I downloaded Stellarum, which seemed to be a great free app, but it simply kept crashing on my laptop... Searching for alternatives I found SkySafari 5 and Starry Night 7. Given the prices of Starry Night 7 and the fact that it isn't to be found on the AppStore, I went ahead and downloaded SkySafari 5 Pro. It is a beautifully simple app which does the job just fine and gives me the needed input to satisfy my thirst for knowledge (at least for now). At this point, I was wondering if someone knows if Starry Night 7 was up-gradable? So let's say I buy the Enthusiast Edition and wanted to up-grade to the Pro or even Pro-Plus version one day. Do I have to buy the App entirely new or does it give the opportunity to up-grade for a few bucks to the next edition? Enough rambling an off to my stargazing site! I arrived well early before sunset, which gave me the opportunity to once check again, if my finderscope was well aligned with the 'scope. It also gave me the chance to let my 'scope acclimatize the same way as last time and so I sat back and waited a little until the moon gained a little on contrast as the sun was setting. The Moon The Moon, being a waxing gibbous, shone bright in the slightly dark blue night sky with literally NO clouds in the sky. I put my 15mm BTS eyepiece in and looked at the beautiful moonscape. It is defiantly the first time I've seen the Moon so up-close and I was in awe by it. I never imagined that it could be so nice to look at all these craters and I began to wonder where they all came from. It is simply a battlefield of craters and each and everyone has its own story to tell... after a good 30 minutes of switching between the 8mm and 15mm eyepiece and lots of "ohs" and "wows", I figured I could try and photograph the Moon with my phone through the eyepiece... what seemed to be a really stupid idea at first turned out to be a really great shot (I think?)! (very little photoshop-magic to increase contrast and sharpness) Jupiter Next on that nights list was Jupiter. I remembered the image last time I looked at it and I was thrilled to already clearly identify Europa from Io through the finderscope. I managed to see Callisto, Ganymede, Europa and Io. I think that Jupiter itself was a little less contrasty as last time BUT I think I could make out the Red Spot which really made me happy! I was so thrilled by the view I even can't write down how I felt... I switched from 15mm to the 8mm eyepiece and focused in... I kept focusing and focusing and focusing but nothing happened... As I looked up in the sky I was shocked... the beautiful cloudless sky had turned into a thick carpet of Cumulus Cumulonimbus... I immediately looked at the horizon on my right to see if there was a slight possibility of clear sky but the enemy had invaded the sky... To make matters even worse at that moment, I met my locations' neighbor, which is no other company then Arcelor Mittal... The sky with the clouds lit up in a bright orange from the molten metal... At that moment I knew it was over for that night... Thanks for reading Abe
  5. Hi there astrofriends, I write this partly to express some frustration, and partly to warn others about potential problems with this product. Last week I ordered an Explore Scientific 12" (305 mm) f/5 Ultra light dobsonian from astroshop.eu, as these were on a significant sale (~ 83% of the price a few months ago) and I was hooked. The package arrived very swiftly in exactly one week. No complaints with this one. On opening the boxes everything seemed well packaged and fine. However, when opening the main parts, rocker box and mirror box, I found tens of metal shards everywhere, of the kind produced when one drills on metal, many were very small others were pretty sizable (several mm). These where in every possible corner, burrow and small cavity that you can imagine. I proceeded to vacuum clean as careful as possible every one of them. I was naturally anxious though that these shards might have damaged the optics during transport and, indeed, upon close inspection I found a small scratch on the main mirror. To make things worse, I even found two metal shards several millimeters in size *inside* the paper wrapping the secondary mirror, which, to my horror, but not surprise, also has a scratch. Obviously, an email has been promptly sent to astroshop.eu about this (I will do the same to Explore Scientific shortly). I understand that I might have been utterly unlucky, but as a recent review in Cloudy Nights also tells of the problems with metal shards in a scope of the same family it might be possible that some productions routines have been a bit careless (to say the least). Please, if you are considering buying any of these scopes think twice. Best, /H.
  6. Hello folks, for long I have been browsing the internet to find a suitable 10in dob and despite lack of reviews, I have decided to take the plunge with the Bresser Messier 10in Dobsonian. There was some doubt at first, especially when considering the popularity of similar scopes from Skywatcher, Meade and GSO. Even though Bresser is relatively new to the market, it has some clever features: 1. The massive 2.5in hexagonal rack and pinion focuser is very solid and the movement is smooth. Despite being only single speed, Bresser sells an a dual speed 10:1 extension. However, I find the movement precise enough and do not need the extension at the moment. 2. Optical finder scope feels a bit cheap but it is a nice upgrade over the red dot finder I had on my previous scope. 3. Rocker box style base allows disassembling the scope into two pieces (OTA and base). 4. Tube rings allows the scope to be easily balanced when adding weight + after adding a suitable dovetail plate, the OTA can be used on an equatorial mount (if you plan to upgrade to an eq mount, I would consider the 8in model, as an eq mount for the 10in would be expensive). The only negative comments I can give about the scope is the production process. There were some minor issues with the assembly with the scope as parts did not fit properly. First problem was with one hole drilled deeper (loosening the particular screw fixed the issue). Another problem was with the altitude wheel as it made the OTA to pop out from the rocker box. (A loose screw on one of the plastic pads between the box and altitude wheels was causing this. Make sure all these screws are tightened and below the surface of the pads). Lastly, I assume there must have been a mistake in the quantity of items included (I got twice as many screws for the rockerbox and 2 eyepieces instead of one, both were 25mm super plossl but the standard was a 1.25in advertised on the bresser webpage, while the other was a 2in wide angle) I did not have the opportunity to test the scope outside properly due to clouds. Update: 01.06.2017 Had the chance to try it out on the moon and jupiter to a max magnification of around 160x. The results were very sharp and detailed views. Unfortunately, clouds rolled in before it got dark enough to observe DSO's. I am waiting for clouds to clear and a package with a 42mm wide angle eyepiece and a 2in GSO 2x ED barlow to arrive next week.
  7. Dear all, Recently I purchased one of these dobsons from ES following the good critics I read in several forums. The Gen II includes some improved features with respect to Gen I, 2 Nylon pad brakes, Virgin Nylon alt and azimuth support bearings (instead of plastic), counterweight bar included with a couple of 1kg counterweights, a classical ES dovetail for the finder. Some of these improvements were demanded by Gen I users, and are highly appreciated, but there is still some minor improvements that the final user has to apply. I will describe them lately. The set up is very fast, less than 15 minutes, though the assembly of the upper cage needs some patience the first times is done. Regarding the optics, It is superb, though in my opinion the 75mm minor axis secondary is too big (other similar modes in that range use a 63mm one), it provides full illuminated views on my ES 100 degree eyepieces, the stars in the background seen in clusters like the NGC457 are astonishing. The main mirror cell support is a mix of support concepts, a nine point mirror cell support with a couple of rubber wheels at 90 degrees, and 3 glued slings to the mirror laterals screwed to the back of the mirror cell support, provide lateral support for the mirror. The collimation as in Gen I is done from above in less than 5 minutes. In the first light in semirural skies the views confirmed the good optics, as I said specially in star clusters the amount of stars which could be seen in the background increased with respect to my 200PDS, the globular clusters were literally smashed, and small planetary nebulae like M76 showed internal details. Coming back to the cons, as in any Chinese made product there are quality problems not solved in this Gen II, the paint coatings from the secondary cage just jumped when I changed the position of the truss brackets. When I tried to open the main mirror box for the first time, the scratched the yellow paint from the altitude bearings, a tolerances problem which I solved adding 2mm nylon washers between the altitude bearings and the mirror box. More improvements to make on your own are to make a plywood cover to prevent moisture on the main mirror while waiting for the night, to put foam pipe covers around all the tubes, they make the winter usage of the scope more comfortable and at the same time help with the vibrations damping (which even with a heavy ES 20mm 100d EP where almost insignificant). One more thing to add is a PWM motor controller, the fan only work at full speed, and there are so many nights when the temperature gradient does not fall fast and the fan speed can be left at a lower regime to save batteries. In brief, the ES12'' Gen II, it is the Dobson truss scope with the lowest price in that aperture range, the optics is damn good, the mechanical improvement done in the GEN II, improve a lot the vibrations, and the movements of the scope, though a better control on the tolerances and the paint process should be done. I attach some pictures taken at home and while the first light. Cheers. Mario.
  8. AbeSapien

    Prologue

    Hello there, I thought to myself that it would be great to write everything down I'm experiencing. From the very beginning, to the very end... So I chose to create this blog and use it as my small journal for personal observations, stargazing sessions, thoughts, reflections and what I recently learned. The greatest thing about this is, that it gives the opportunity to kick of many interesting discussions and I really can't wait to get started. Around the end of winter 2017 I started gazing around with a pair of binoculars I found at home. I initially got them when I was 9 years old and literally forgot about them... They were eating dust for 18 years now. After gazing around a little I bought myself some interesting books about astronomy and how to find stars and star maps. I don't know if it was my subconsciousness leading me into ticking off a point on my bucket list, but after so much hesitation if I should buy a 'scope or n... BWAAAAH I cracked and bought one. Period! Which leads us to yesterday night. After many days of reflection and information overkill, I finally went for a Skywatcher Skyliner 200P with BST 25mm, BST 15mm and BST 8mm eypieces. I ordered it last week on FLO and I couldn't be happier! It arrived divided into three packages last night and I immediately had to assemble it! Armed with my cordless screwdriver set to 11nm of tension, it took me about half an hour to assemble it and check if it was collimated right. Collimation was not perfect but it was absolutely okay for a first ride (I really should admit that I am a little anxious to collimate it and it is so near "perfect" that I'm okay with it at the moment). All in all the pictures don't give enough credit on the built quality of the 'scope. It is a simple to assemble and use first 'scope. I'm really glad that all of you pushed me in the right direction. After assembly and cleaning there were ONLY 5 damn hours left to wait until sunset... So I figured to simply develop a small evening plan in what I wanted to watch and gaze at. I simply chose to visit Saturn and Jupiter... Humble and modest for starters but hey, less is more and I really wanted to enjoy my evening out and not dish up myself with a list that a total novice couldn't handle and therefore risk to end up with a very disappointing first night. I'll write up my first experience in the next post and if you're interested, keep an open eye. I'll also use the opportunity to thank everyone involved into getting me started with my first 'scope! So let's go! Abe
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