Carbon Brush

The consensus among users seems to be the wedge is better than front film or filter. Or we all convince ourselves it is better because we don't want to admit to wasting our money🤔 To give a definitive answer on film vs wedge, you would have to read a report from someone you trusted, using the same scope, same eyepiece, same day. I could do this test if I tried. I have an 80mm refractor that I use with a Herschel wedge. I also have a film to fit this scope. But this is still not going to silence all arguments or uncertainties. Your film is a cheap one. Not a 'Solperfect' branded type. In my case the film masks a bit of the objective. You used a Brewster angle Lacerta wedge - what about a Lunt/Baader 90 deg wedge? Was it a 1.25" or 2" wedge? The Brewter angle wedge emits strongly polarised light, which affects the view. So the film test is only valid if you add a polarising filter with a 90 deg wedge. Also quality of added polarising filter? If in the film test, you had a 90deg prism, was it made from as good glass as the solar wedge? Intuitively a decent quality prism has to be better than a wrinkly film on the front. But wrinkly films are surprisingly good! A 200mm (or whatever your scope size) glass front filter can be more expensive than a 1.25" Lacerta wedge. How flat is this big piece of glass? A sheet (A4 size) of Baader film is twenty something quid. Enough to make some scope and binocular objective covers. Just use some stiff card, glue and sellotape to make frames in Blue Peter style! It gets you started. Sorry no easy answers. David.

Just one two more links. If you scroll down you can see a non-compliant fuse like that in @AstroLearnerWill plug! https://www.pat-testing-training.net/articles/counterfeit-plugs.php This is what happens when they have to earn their keep! https://www.pat-testing-training.net/articles/fake-fuses.php

Sorry we are drifting a bit off topic. But still near enough. Also it is a safety issue, not a deliberate diversion off subject. This may be of interest. https://www.pat-testing-training.net/articles/fuse-operation-characteristics.php Also this article describing fuse physical size and construction. http://plugwiring.co.uk/plug-wiring-posts/choosing-the-correct-fuse-for-an-appliance-with-a-bs-1363-type-plug/ I am of the opinion that electrical equipment importers are getting away with far too much poor quality kit that is sold on by retailers who evade responsibility. We see electrical fires in the UK that are caused by 'faulty' equipment. Actually more like poorly designed and dangerous equipment. Yes a few end users put chicken wire in fuse holders, make bodgit repairs on mains leads, etc. But they are the minority. These days most people shy away from anything electrical. Also not all retailers are irresponsible. A few years back I was chatting with an electrical engineer who in a former employment had worked for Argos. His role was head of electrical safety. This included trips overseas (including China) to see the factories as well as liaising with UK trading standards following up fault reports. Certainly while he was there, the company took electrical safety matters seriously. He told me one or two 'interesting' stories! These are definitely off topic and for another thread. I can only repeat my ealier comment. If the lead or equipment are not from a source where you can have confidence safety standards are being met, then swap the fuse. For example if I bought a fan from Tesco, I would be confident it was 'right'. If it came from an amazon marketplace seller, or an ebay seller....... HTH, David.

This is reminiscent of my very first reflector from Orion Optics UK. I took it to a club for help with collimation. 3 of their experienced members turned screws and scratched their heads for an hour before reaching a conclusion. Send it back! Fortunately I had only just received it. So it went back to OO and was returned to me with a new tube. Being new to the game I did not understand everything about the lack of alignment and it was a long time ago. The replacement tube gave very good results and I enjoyed using the scope. Might it be worth you looking for another 10" tube with grotty mirrors, on sale cheap? Either experiment with making lots of new holes, or if the focus and spider holes are near enough right, saw a bit of the back end? In this case, if the primary to secondary distance is not quite right and there is a bit of light spill, does it matter? I have not done the sums but if you have in effect 240mm of the 254mm main mirror hitting the secondary, will you notice? But, do you know the mirror is F4 and not F3.9 or F4.1. I remember seeing a big (24") newt at a club. To help with alignment and collimation. The clever folks at the observatory made a device with motor drive, turning an LED on an arm to help establish mirror position. I'm wondering if something similar might help. A light source (laser pen?) near the tube edge shines down the tube to hit the main mirror near the edge. Then look where it hits (or misses) the secondary mirror. Sorry if this doesn't make a lot of sense. It is a very annoying problem.

Yes this big fast scope definitely calls for an offset. Now there is the correct way (measuring everything) way to do this, which may mean drilling new holes in the tub for the spider. The alternative is to move (more drilling) the focusser towards the open end of the tube. Which, or even both, is called for dpends on the measurements. There is a simpler way that may be good enough. You could fit longer screws on the secondary allowing it move toward the primary mirror so placed under the focusser. Intrigued....Looking forward to the next instalment. David

An advantage of being incognito is that you can ask daft questions and get away with it🤣 Seriously - it is definitely worth a visit. Not far for you to travel and a chance to see and hold all sorts of stuff. Maybe even attend one of the lectures.

A suggestion or two on security if I may? Do not put your security features in an obvious place. Big padlock and hasp says 'insert crowbar here'. Alternatively it says go for the hinge side instead. Apply lower levels of security, but have several in place so even if they defeat one, they have to spend time on the next. That way they are more likely to leave. My observatory looks very much like an ordinary shed with (from the outside) ordinary cheap lock and hinges. If you took a prybar to it, you would find it didn't give way as expected. I won't discuss the details on open forum. Suffice it to say Burglar Bill would I think give it a try, then look elsewhere. He might damage the door, but he would not get in. Consider fitting an alarm system based on an after market car alarm. These run for ages on a 12V battery. Unlike house alarms they are intended to work in temperature extremes. The decent models accept several inputs from normally closed, or normally open switches corresponding to door switches, bonnet switch, etc. Use the switch inputs to trigger if the door is opened, or the roof is moved. You can run a thin wire around the walls that will break if a plank gets pried off. Again using a switch input. They also have shock and vibration sensing - car park nudge alarm. This comes into play if someone decides to hammer off the padlock or hinges. When the alarm does go, install LOUD sounders inside the shed. Make it painful to stay. If it is loud inside they can't hear anyone approach from outside so are likely to leave. Big bright lights on alarm trigger are a good idea. Do not rely on a single sounder, or a single light - site them so they are not easily disabled by a brick or hammer. All of the above are on my observatory. HTH, David.

Most scope fixings and mounts have a bit of flexibility or elasticity. If your target hides behind the wires, gentle pressure somewhere on the mount will bring it back into view. Release the pressure and the mount returns to the correct place. When the target only shows while leaning on something, you are in the right place. I have used this technique quite a few times on various combinations of scope and mount. HTH, David.

Hi Samop and welcome to SGL. Rule 1 of SGL. There is no such thing as a stupid question. We have all been there. If you want to use the scope for basic solar viewing, you leave the cap on and fit an approved filter material over the small hole. This significantly reduces the amount of energy that is put on the secondary mirror, and the eyepiece. For example Baader solar film. WARNING...Solar observing is dangerous without the right equipment and your eyes don't get 2 chances! Make sure the film/filter is secure and can't fly off in a wind. For viewing a bright moon, I would use a filter to dim at the eyepeice end of things. By keeping the full size of the mitrror, you can use high magnification. You can buy a neutral density (ND) filter for fixed dimming. My preference is a variable polarising filter. HTH, David.

My first proper scope, almost 20 years ago, was an 8" reflector on EQ. Since then I have owned various scopes, but always had a biggish reflector in the collection. A used 8" dob won't set you back too much, giving a good start on saving up for the next scope😁

Not providing information in advance seems to be a recurrent feature of astro shows. The organisers know all they have to say is 'astro show at place and date' and the masses will mass🤣

While thinking about using mains on astro kit....... Many items (originating in China) have a 13A fuse in the plug. A one size fits all solution. A bit like chicken wire in a home fuse board🤔. Always when you buy a lead or equipment check the fuse. For example ,small items (like the clone Canon coupler) take very little power. Use a 3A or lower fuse. Always rate the fuse according to the equipment. A lower value fuse will ensure events like the OP cable failure have a quieter BANG! Another problem I have seen on some Chinese equipment is fake fuses. Yes FAKE! The fuse used in our 13A plugs is 1" long. The fuse wire is NOT taken beyond the ceramic tube and bent over. It is internally fixed. Those above are two giveaways I have seen on fake fuses. Another one that you don't see unless you break open the fuse is the filling. A properly made fuse contains a fine sand to quench the arc when there is a big fault to vapourise the wire - yes it happens. I have seen fake fuses without the sand, which means the energy transferred under fault is far higher. When I challenged the equipment manufacturers, they tried to fob me off with what are best described as fairy stories. As the parts had come from amazon, that was where I went next. amazon withdrew the items from sale. Though probably a less than scrupulous marketplace seller remarketed a week later under a new name. Needless to say, anything not bought from a big name with known quality controls is best treated with suspicion. The amazon marketplace and ebay sellers........... If in doubt, swap the fuse. A known good fuse purchased from an assured source costs pennies. HTH, David.

Mains on a scope is to be avoided if possible. Elastictrickery on wet grass and all that. Don't forget the 'average' cable is intended for use around room temperature. They become very stiff when cold. Unless you buy low temperature cables, sometimes known as arctic grade. In this case the outer plastic fractures, exposing the conductors and one twist later BANG. Another factor is the PVC degrading. Take a brand new cable, and a few years old apparently identical cable. The old one will have stiffended, especially if exposed to UV, or solvents, or oils. In the big money pit of astro imaging, new cables every year or two, or better quality cables, are insignificant. This goes for all the cables. Mains, 12V power, USB, network, etc. HTH, David.

Hi Carole. They are in Worksop. North Nottinghamshire. A few miles from clumber Park and of course Robin Hood country, should you visit😀 http://www.shedshedsheds.co.uk/

Can't fault you on a big-ish reflector and dob mount. Been there and got the T shirt. As you are buying a simple scope and mount, do think about the used market. You will get even more scope for your ££ spent😁 Do think about the size of the tube and base. They don't go into the broom cupboard like a refractor and folded tripod🤔 Navigating from storage to use viewing area? Keeping cost down, a Skywatcher mount (and others) are essentially melamine faced chipboard. Every one I have encountered has benefitted from a bit of tweaking. Poorly adjusted clutches on motor drives, rough lazy susan bearing, etc. At the other end is an aluminium framed mount like the Orion Optics offering. Yes they work well but they hit your wallet harder. Now to mirror size. 8" easy to handle. 10" a bit of an effort. 12" is huge. My experience of a Skyatcher flextube 10" (vs rigid tube) was positive. I would definitely look at one again. HTH, David.

Well Norway is much too far away for me to offer to help with cleaning and re-assembly. Then again. superb scenery, chance to see aurorae.......🤣

Propane or butane evaporate at room temperature, leaving nothing behind. There is something else that left a residue in the 'air' spray. Are you sure it wasn't 'hair' spray🤣 Seriously, if you don't know what the residue is, it might be harmful to a mirror. It might also be quite inert. Is there anything on the can ingredients list to help? If it was my scope, I would clean the mirror. Whether you do this depends on your skill/risk thinking. If you add your location to your screen information, you might get an offer of help from a friendly local. HTH, David.

This thread contains some information you may find useful. It also links to ther older threads, with hopefully useful information. A lot to read! David.

Determining 'easy' depends on your skill and experience, as well as the right tools and materials. I'm not sure I fully agree with @Peter Drew this time - a rare event that warrants an explanation.😁 A compressed air canister should contain only dry air and a propellant that readily evaporates. Given that the 'air' has left room temperature residues on the mirror, the manufacturer may not have good quality control. Who knows what nasty stuff was lurking the can? If it is a non reactive grease no problem, but something else? Yes mirror coatings are physically tough and non reactive. But proving this with (for example) bird droppings and fungus does not end well. The quantity of non-shiny stuff on your mirror does not warrant cleaning. It is the nature of the material that would worry me. If you do clean, there are several methods and different takes on choice of solvents and soaps. But there is one common factor - patience. David.

Thanks for posting the pictures. These will be a big help to anyone considering using the company. A second for the comment by @malc-c about the pier/pillar being on the ground, not shed floor. When I asked for a hole in the floor of the shed I bought, they thought I was a bit odd! A suggestion if I may? When the roofing felt starts to fail - which it will before too long. Do not replace it! A strange thing to say I know. But use pond liner. I roofed my roll off using butyl pond liner in 2007. It is still there leak free. This includes a section that hinges 90 deg every time the roof is opened or closed.

Just my two pennorth on this one. I regard SGL as primarily a discussion and help forum. The buy/sell is a minor part. I don't think we need feedback. Before I buy something from a member, I take a look at their history. 11 scopes, 4 cameras and 6 mounts for sale in 6 weeks and a genuine reason for sale? Posts last year talking about using the scope that is now on sale? Is the seller a helpful forum contributor or mainly selling items? I think you get my drift. If I meet up to buy, we invariably have good chat. It is good to meet up face to face. Only one meet up didn't work as planned. The seller was quarantining for health reasons. I bought the kit from his back garden with him looking through the window! This was of course followed up with a long phone call before I set off for home. If it is a posted item, I always respond with a safe arrival & thanks message. By researching before buying, we avoid worries. For example last year I bought an item from a member here and it didn't arrive. The seller had sent an image of the Post Office paperwork, so I was not worried. In addition, the seller had a long history on SGL and I had bought from him before. No worries. The seller was clearly bothered about non delivery and offered immediate refund. Given the history, I said wait. I remained relaxed about things. About 3 weeks later the parcel arrived. No apology from Postman Pat, nothing to indicate it had shipped via the Outer Mongolia sorting office. Working the other way, I sold something to a long standing SGL member. I posted it and told him to send the money once he was happy with the item. Yes the cheque did arrive in the post👍 My SGL buy and sell experience has always been postive in terms of the item quality, honesty about defects and limitations, etc. I have got to meet a lot of really nice people face to face, which makes future phone or PM interactions about items so much easier. The nearest to a negative has been a small (actually tiny) number of people who could have packed a bit better to survive the rigours of a UK carrier. But nothing serious has happened. I'm not convinced buying via SGL has saved me money. In reality I have spent the same money as new, but met nice people and obtained much more equipment😁 Long may this continue. David.

Even with bad light pollution, there is a lot you can see with a simple telescope and you don't have to stay out long. For example in the past few days Jupiter, Venus and the moon have lined up nicely in the evening sky. All are bright so get through the urban glare. Later on Orion is well placed. A telescope looking around the belt, sword and nebula give great views. The reason I mention these objects is they can be viewed quickly (before you get cold) using a simple scope that is quick to set up and take back inside. If you have a solid garden table, or even a wall at resonable height, it is a good place for a scope. Easier than a tripod on the ground. Ways to keep warm are another matter. But layers, woolly hat and gloves are good starters. HTH, David.

At risk of triggering another heated debate😲 If a mirror has toxic or reactive deposits, clean it. That includes fungus, bird dropping, serious tree sap and pollen. If a mirror is a couple or 3 years old and just has a few bits, leave it for another day, or year. After 35 years it will pick up a lot of debri, whether harmful or not. Cleaning is warranted. Mirrors can be sfely cleaned with the right technique and materials. However, there is always a small risk of scratching or other damage. If a mirror looks really grotty, I clean it. If it is not really grotty but the scope is in pieces for other reasons, I clean it. Otherwise leave alone. Looking at the image provided, I think your scope is in the look again another day/year category. You can have a lot of stuff on a mirror and still get good views. HTH, David.

Iso-propanol. Or the older name is isopropyl alcohol. The 70% ingredient in the hand gels we have been using in the past couple of years. Also used in some electronics cleaning. Pinted circuit boards and components. Beware. electrical 'Switch cleaners' often contain other things. However @westmarch if you would like to send me a crate of beer🤣

@AstroKeith Another thank you for your detailed description. I use Baader fluid on lenses. On the basis that I don't use it by the litre and a 100mL bottle costs a lot less than the lens. When away from home the little spray bottle is convenient. For the future, I will definitely try the IPA/water/soap mix. Perhaps refilling my empty Baader bottles.