Mandy D

It might not be possible to get an extension tube, but you could get a collar machined in aluminium to effect a 25 mm spacing. It might not be the perfect solution, but I have done this in the past. You just need to take care to ensure the eyepice is properly secured in the focuser.

Thank you. As I said in my post, this is all purely for imaging, not visual. So, the Barlow would have to go after the diagonal to maintain it's multiplication factor, but the focal extender can go anywhere in the imaging train is my understanding. So if I put another 75 mm of extension tubes on the back of the scope and the rest of the gear behind that, I'm good to go? No diagonal needed.

This is not something I have ever thought about and it is a very valid point, which is backed up by my own experience. I bought my Skywatcher 200P through this forum, but I already owned a 250PX and an RC6, so I had some idea of what I was looking at. The view through the eyepiece was completely white and nothing was coming into focus, but I figured it may have been to do with being indoors and nothing distant to focus on. The primary mirror looked fine and clean, as did the secondary. The focuser racked back and forth smoothly and everything else about the telescope was good, so I paid my money and took it home. Outdoors with distant views and sky available, it would still only produce a uniform white image, no matter what eyepiece or focuser setting, which left only collimation. Fortunately, it came with a cheshire, so I set about collimating it. The primary mirror was so far out, no part of it was visible in the collimator or eyepiece, but it took less than five minutes to bring it into near perfect collimation. A newbie would probably have rejected this perfectly useable and well-priced scope or having bought it been unable to fix the problem.

It may not be a great telescope, but it is what you have. You've paid for it and want some use out of it. Does it focus clearly on the Moon? If so, it is useable. As for imaging with it, you have seen the previous comment, but keep in mind that any carefully chosen accessories you buy for this telescope will work with anything you upgrade to later. Buy a couple of decent plossl type eyepieces for not a lot of money, a 10 mm and a 20 mm should be good starters. Get your kit to mount your phone on it and see what sort of images you get. If your expectations are not high, then you may be happy playing with this for a while until you save up enough for a better scope. Try these eyepieces: https://www.firstlightoptics.com/astro-essentials-eyepieces/astro-essentials-super-plossl-eyepiece.html OK, two will cost more than you paid for your scope, but they will work with a better scope later. If you are only buying one, then go for the 20 mm. The magnification will be lower at 50x, but the viewing will be better. Does your Sony camera have a delay timer for the shutter release? If so, use it. This will reduce camera shake and result in better images. It looks like your scope is on an equatorial mount, which can be tricky to use manually for beginners. Try pointing it at Jupiter or Saturn. These are easily found in the night sky from the UK at present from early evening until after midnight. You will easily see the four Gallilean moons of Jupiter with it and should be able to see Saturn's rings. Mars will appear as a reddish disc and, if you are lucky, you might see some detail, but don't be surprised if you can't. One other target I would point it at is the Orion Nebula, M42 in the constellation of Orion, rising late evening towards the south at the moment. You won't see much, but at least it will be a fuzzy patch and not a dot like the stars, so you'll know you have found it. Use Stellarium to navigate around the night sky, as it will help you find objects and you will learn to use your telescope better. https://stellarium-web.org/ Come back to this forum for more help as you need it.

I have a 2 inch Explore Scientific 2x focal extender and an RVO 2x ED Barlow that I am trying to use with my RC6. I have 100 mm of extension tube fitted, but it appears I need another 75 mm to get focus with either of them. I'm not using a diagonal as the aim is imaging, but to test all of this I am using an eyepiece. I can achieve focus with my DSLRs and no extender or Barlow with either 75 or 100 mm of extensions. Is this expected and if so, what is the most practical solution? Edit: FLO have 50 mm M90 extensions at £39 each, 25 mm at at £35 and an 80 mm 2" extension tube for £35. I am thinking that the M90 extensions will result in a more rigid setup than the 2" eyepiece extension tube as they go in front of the focuser and are larger diameter and screwed into place. If I go for 2 x 50 mm, rather than a 50 and 25 this will allow me to have fewer threaded connections to achieve the required 175 mm total and increase rigidity for just £4 more and gives me up to 200 mm. The advantage of the eyepiece extension tube is that it will also work with my Newts. Is my proposal realistic? I can always get the eyepiece extension tube for the Newt as well at a later date.

It is very much more about the story telling. The big thing I like is the lack of typographical errors. You'd think, with computers and spell-checking, that it would not happen today, but you just cannot beat an experienced and skilled proof-reader, which was my grandmother's occupation.

Thanks. That is great to know. Any idea how much it moves the focal plane? I'm currently able to image with 75 or 100 mm of spacers on my RC6 with the D800. Do you know if I need to remove more and roughly how much?

@L8-Nite I have a slightly older edition of Story of the Heavens, by Sir R S Ball. It is not as attractively bound as yours, but is from 1890. I'm currently reading it from cover to cover. It is remarkable how advanced the Victorians were in some aspects of their understanding of the universe. Right now, I am reading how they used deviations in the orbit of Mars to weigh the Sun and Earth.

My new, secondhand, Explore Scientific x2 focal extender purchased from @HollyHound arrived today, well packed and in it's beautiful original box. I just need some clear skies and the energy to get out there and use it, now. Thanks, Gary.

I don't think that is Neptune (or Uranus) as it is in completely the wrong place. Have a look on Stellarium and set it to the time and date the photo was taken and you might be able to figure out what it is. Also, it is helpful if you tell us what telescope was used so that we know whether it mirrors or views things upside-down, etc. If your images are erect and not mirrored, then in the lower one, Neptune would be way, way over to the right of Jupiter following a line drawn through the moons. Probably about ten times as far from Jupiter in your image as the distance across the moons. https://stellarium-web.org/

There are acids and oils in organic materials such as that extruded by slugs, which will attack most metal surfaces. Stick a finger print on a piece of bare polished metal and see what happens over a few days or weeks. OK, your mirror should have some form of coating over the aluminium, but no guarantee that it will fully protect it from acid attack.

@Marvin Jenkins It is common in historical records, particularly around inventions to find things "incorrectly" credited. Often, the person who made the most significant contribution is credited as the discoverer or inventor and the person who was first is over-looked in the history books. A well-known example is the light bulb, the invention of which is frequently and erroneously credited to Thomas Edison who was a fantastic self-promotionalist. If you are at all familiar with the history of electric light you will know that Joseph Swann got there before him, but there were others who pre-dated Swann. However, none came up with a commercially viable product. One of them was none other than Humphrey Davey, the chemist.

Try this: https://www.freeease.net/i-videotogifconverter/overview.php

It'll probably depend on dT/dt ... If that is sufficiently low, should be OK.

That is all good to know. From the blurb on their website they seem very professional, but it could have just been marketing spiel. I don't understand why they are not pushing the pure sine wave bit, as that is most important and highly desirable. To check the output waveshape you would need an oscilloscope or harmonic analyser. I would not rely on any inbuilt display for that, as it is so easily faked. I did notice that many of the "photos" on their site are actually computer generated graphics and not images of real product, which is what made me ask all the questions. If a company has product, why use anything other than genuine photographs? I'm planning to build a mobile "observatory", so something like that unit could work well for me. Thanks.

Oh, I totally agree. I am a big fan of Newts as you know and understand their benefits for imaging! It is curious that you mention fluorite as a type of glass used in refractors, as I was just reading up on a particular type of fluorite a few minutes ago, which is only found here in the Derbyshire Peak District. It is a most beautiful example of the mineral. Here is a link to one of the articles I was reading: https://bluejohnstone.com/the-ridley-vein-discovery/ I was in Castleton, yesterday, after photographing the solar eclipse at Stanage Edge a few miles away, hence why I was reading about flourite.

Well, if anyone ever suggests that an 8" Newtonian is not an imaging telescope, I think you have just proved them wrong! Wonderful results! Keep showing us what is possible with modest equipment.

This looks like a nice, professional product, made in USA and distributed by a company not far from me in Bolsover. The company offers bigger systems too that should be capable of running an off-grid home. Do you know if the output is pure sine-wave as they shy away from discussing this on the site or in the instruction manual, which I find slightly concerning. They also do not state the output frequency in the manual, but note that you can change it in the settings. They explain what frequency means and state that it is usually 50/60 Hz. I wonder if it is a binary choice or a continuous range?

EW14 welding filter?

Well done to everyone who caught this. Some truly impressive images in this thread. Here is my best effort of the day:

So, it was your cat that took a bite out of the Sun, today ! 😛 Seriously though, those are superb results! Mine aren't even close.

You can create great constellation photos with short exposures and short(ish) focal lengths. Orion is one of my favorites and is nicely positioned around midnight at the moment. If you want to make it more intersting you could go for creating diffraction spikes on the brighter stars. This will happen naturally with a Newtonian reflector telescope due to the secondary mirror mounts, but you can always stick some wires across the lens of a camera at right angles to create the same effect. Really, you probably will not need much processing of this type of photo. If you have a tripod and can adjust the exposure time, aperture and ISO (or any of those) you can improve results. High ISO tends to be noisy, so wide open, low(er) ISO and follow the guidelines for exposure time as given by others.

We got beaten by the clouds. Lovely and clear on the drive to Stanage Edge, then heavy cloud until the eclipse ended, followed by bright sunshine and blue skies. The Sun didn't show for long enough to allow me to point the 200P at it, so I ended up shooting with the 300 mm prime on the D3200 with no filters, relying on the clouds to do the filtering for me. So, overall a rather poor session, but did get this composite image.

Superb! I only got white light through cloud.