Ricochet

It might, but then you might have the opposite problem that the edge is too far away. Remember with the premium cheshire you don't have to insert it all the way into the focuser so you can gain a couple of inches of travel that way too if needed.

Fair enough! My garden isn't perfectly flat and the dob copes with being a small amount out of level but if you've got serious changes I can see where the built in adjustment of a tripod will come into its own. I would definitely factor in getting a handle to the purchase cost and would probably err on the side of smallness as extra weight and difficulty will dissuade you from getting a telescope out (or rather, you'll just get a smaller frac out instead of the newt).

Not quite. I use a a premium Cheshire for my secondary and switch to a short Cheshire with the crosshair a removed for the primary. I used to use a barlowed laser for the primary, but the batteries ran out and I still haven't got round to replacing them. This is the style of short Cheshire I have https://www.ebay.co.uk/itm/293772110824. You might find sellers with even cheaper prices, that was just the first search result.

No. You can't centre the secondary under the focuser with a laser, you have to start with some sort of sight tube, be that a combined cheshire/sight tube or concenter as suggested above. The laser can then be used to align the secondary to the primary, but the problem with the Baader is that it doesn't have an angled face to allow you to watch the collimation change from the primary end of the telescope when you collimate the primary.

Aside from already owning an AZ100, is there any reason why you're looking to mount a Newtonian on an alt/az tripod mount rather than buying a Dobsonian? Holding either an 8" or 10" tube with one hand while tightening the clamp with the other seems like quite a difficult prospect compared to simply placing the OTA onto a dob mount. Of course the Bresser dobs have tube rings so there is the possibility of trying both mounting options if desired.

This should do the trick https://www.firstlightoptics.com/dovetails-saddles-clamps/astro-essentials-vixen-type-photo-dovetail-bar.html

No, experience. 🤣 If yours is like mine there is enough strength in the battery holder/laser assembly that it will hold position in the v block without any of the collimation screws touching it. You can then carefully tighten just two of the screws to collimate and then nip up the third one, hopefully without pinching the batteries again.

The collimation screws for the collimator push against the sides of the battery holder. Someone has tightened them too tightly and now they are digging in and preventing the battery from being able to pass down the tube. You will have to loosen the collimation screws, change the batteries, and then recollimate the collimator.

Separate eyepieces will be beneficial at some stage. The ones supplied with a telescope are just cheap stater eyepieces to get you going. However, you should spend as much money as you can now on the best scope you can afford, and worry about upgrading eyepieces at a later date. If you can push the budget to £150 the heritage 130p would be my choice, if not then I would take the heritage 100p over the original options.

Does that little metal cap that has been exposed pull off? It might be that it is supposed to be attached to the part you have already removed. The dull grey tube beneath it contains the batteries. The laser part must be at the end that the beam comes out of, else the batteries would get in the way of the beam.

Newtonians have much flatter fields than refractors. I don't recall anyone complaining of field curvature in this "flat field" eyepiece. If you are seeing field curvature (and not coma) then I would suggest that you return the eyepiece.

What is your budget? I would go for something from the Skywatcher Heritage range over your current choices, even if you have to save up/increase your budget to do so.

It is based on experience of using the Starguiders and reading similar reports about the X-cel LXs, which make sense considering the design of these eyepiece lines. Essentially, each eyepiece is the same 4-element set of lenses with different singlet or doublet barlow-like lens in the nose piece. The shorter the focal length of the eyepiece, the stronger the "barlow" and the slower the light cone when it reaches the main set of lenses. As slower focal ratios are easier for an eyepiece to correct, you can see why the shorter focal lengths are better corrected.

This ^. Once you've (@merlin100) done that, adjust the secondary so that the doughnut is centred under the cheshire crosshairs (the big fuzzy ones in your photo). After that, adjust the primary so that the dot is centred in the doughnut.

Having used the 1145P and some of the eyepieces in question I would say: The 5-12mm Starguiders will work well in your scope The 5-12mm X-Cel LXs will also work well in your scope. Having owned a 7mm I think they might have better coatings than the Starguiders, but having sold it I can't check. If they do have better coatings then yes, they are worth the extra money, but if they don't then maybe not. The 18 and 25mm Starguiders and X-Cell LXs will be awful in your scope. At the longer focal lengths I suggest you look at the Explore Scientific 68° range. If you want to maximise FoV then go for the 24mm, if you think the exit pupil is too large, perhaps the 20mm instead. As you will get a 25mm with the telescope you can check this for yourself before you buy a replacement eyepiece. A 2X barlow will be useful with the short focal length eyepieces to try to squeeze a bit more magnification out of the telescope for lunar and planetary. You won't be anywhere near atmospheric limits without the barlow. Also, finding a way to increase the diameter of the focuser wheel will greatly increase the ability to focus the telescope. I made a 3D printed ring to push fit over one of the wheels and was so impressed with it that I made one for my own scope the next day.

Aligning the doughnut on the primary mirror with the crosshairs is part of the secondary collimation. When you move on to the primary collimation the goal is to put the shadow of the hole in your collimation cap in the centre of the doughnut. At this stage it is useful to not have cross hairs obscuring the view. I use a long cheshire/sight tube (the red FLO one) for all secondary collimation steps and a short cheshire with the cross hairs removed for primary collimation.

Find an eyepiece that you can use in your binoviewer and barlow with no vignetting. Put a star in the centre of the FoV and use a stopwatch to time how long it takes to drift to the field stop. Do this several times and take the average. Now do the same thing using the eyepiece in your telescope with no binoviewer or barlow. Divide this number by the first number to get the effective power of your binoviewer/barlow. Once you know this you can use it to calculate the eyepieces you want to buy for the binoviewer.

I've got an 8" bresser dob from the first run and I have added 100mm to the height of the base because I swapped the then supplied RDF to a Telrad and 9x50 RACI and needed to move the OTA further back in the rings than the original base height would allow. I've also added some shedmates to the base to lift the chipboard base up a bit from any wet grass beneath. I sit on a drummer's stool to observe. I do not recall having any problems with the height prior to my modifications, but the planets were higher back then. With the planets as low as they have been recently I've had to observe with the stool at its lowest setting, and so the extra 150mm height has been quite nice to have.

@Lockie has done a few videos on this scope. You may want to watch his first video on it to get an idea of the size. The start has some measurements and weights, but he also picks it up near the end which is probably quite relevant to you. In terms of weight, almost half of it is in the base so potentially you can lighten things up a bit if you can find a lighter mounting solution. Have a look at the following thread where a user mounts the smaller 130p almost directly onto a (relatively) cheap photo tripod. I've got the same tripod and would guess that it is a bit wobbly, but when weight and packed size are the important criteria I think that would be acceptable. This method could also be used with other telescopes. A small Maksutov, say the 90 or 102mm model would be relatively easy to take, but the maximum field of view is quite a bit narrower than the Heritage 130p or 150p if just scanning the skies is something your son would like to do. However, with a 45° erecting diagonal, a Mak could be used for terrestrial targets during the day, which isn't something that you can do with a Newtonian reflector.

You would have to loosen the screws that hold the primary mirror cell to the telescope tube, and then shift the whole mirror cell to align the primary. This assumes that your doughnut is now in the centre. Personally, I would always use a cheshire/sight tube for the secondary so that you have the cross hairs as a reference.

If you want to watch drones flying around then I think the best option is to go with something that birders woukd use, and look for a decent spotting scope. I think the Celestron Regal series is probably the cheapest decent option. However, spotting scopes are not really good for observing planets. The best compromise to observe both drones and planets is probably a small Maksutov, say 90 or 100mm, but the field of view will be quite narrow which may make tracking drones in flight difficult.

Az is easier to use in terms of understanding how the mount moves and switching from one object to the next and initial setup. Eq is easier once set up if you want to track a single object for a long time. With regards to the scopes, the Mak is mostly a planetary and lunar scope, while the startravel line are best at low power, wide views of star fields and large DSOs.

I've looked through Starguiders in the slightly larger 114mm f4.4 and found that the 3.2 Starguider is quite difficult to focus and tends to give quite soft images as a result. Barlowing the 5 and 8mm Starguiders gives much better results and would be my recommendation on a budget. The barlow sold by FLO as astro essentials is actually pretty good and can also be found on eBay for under £10 direct from china. I've not used the "planetary" eyepieces but they tend to get decent reviews and I expect that they would perform quite well in terms of correction at least as they feature a negative lens group in the nose which effectively slows the focal ratio before it gets to the positive lens group (like the starguiders). I've looked through a generic 8-24mm zoom and perhaps it was a dud one, but I thought it was absolutely awful.

There's a first time for everything, usually it's the other way around. 🤣 Astronomik make the filters in Germany, ship them to the USA where they are checked by Televue, then they are shipped back to the UK to be sold to us. You've got two lots of shipping and import taxes, plus labour costs for the additional QC check which I think can easily make up the difference between the "standard" Astronomik and the Televue OIII filters. Is there enough variation in the quality of the filters to make that additional QC check worth the cost? I guess it is up to each buyer to decide.

I don't think you can scrimp with filters. I would look at the Astronomik and the Televue (made by Astronomik) OIII filters. I've also got a Baader OIII, with an even narrower bandpass that only covers one of the two OIII lines, and that shows the brighter (denser) parts of the veil well, but it doesn't show the looser, more subtle parts that blend into the background sky like the Astronomik does. The cheaper "OIII" filters tend to have too wide a bandpass and with them you are more likely to see nothing at all.