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Everything posted by Mandy D
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What was your worst astronomy purchase?
Mandy D replied to sojourneyer's topic in Discussions - Scopes / Whole setups
That would have to be my Daystar Solarscout. It has never showed anything beyond a dull red disc, with no hint of corona, flares or surface granulation no matter what settings I have tried. The Sun just wobbles around like a misaligned Polaris as you try to focus the thing. Worst astro purchase ever. -
What is Your Droolworthy Telescope?
Mandy D replied to Mandy D's topic in Discussions - Scopes / Whole setups
Interesting read. It looks like a very nice job you've made of it, especially considering your limited experience in building such things. -
What is Your Droolworthy Telescope?
Mandy D replied to Mandy D's topic in Discussions - Scopes / Whole setups
That's a nice setup. -
What is Your Droolworthy Telescope?
Mandy D replied to Mandy D's topic in Discussions - Scopes / Whole setups
Yes! Yes! Yes! That was one of the things I was looking at. That and the awesome landscape it is set in. I'm almost tempted to make my observatory to that same design, only a touch smaller. I still want the Planewave, but the observatory is droolworthy, too. -
What is Your Droolworthy Telescope?
Mandy D replied to Mandy D's topic in Discussions - Scopes / Whole setups
Hard to beat, hard to mount, hard to afford, but what a refractor! Great choice. -
What is Your Droolworthy Telescope?
Mandy D replied to Mandy D's topic in Discussions - Scopes / Whole setups
That is an interesting and conservative choice. I guess it is the sharp optics that drew you to it. -
What is Your Droolworthy Telescope?
Mandy D replied to Mandy D's topic in Discussions - Scopes / Whole setups
Yes, I think you are right. These are awesome. I like the ASA AZ2000 RC at a cool £3 560 000.00. -
What is Your Droolworthy Telescope?
Mandy D replied to Mandy D's topic in Discussions - Scopes / Whole setups
@tomato The Planewave is a tough one to beat. Maybe I set the bar too high at the start. At least it won't break down as much as a vintage car, spending more time in the garage than on the road, so to speak. -
What is Your Droolworthy Telescope?
Mandy D replied to Mandy D's topic in Discussions - Scopes / Whole setups
@doublevodka I can see why you like this. It has very clean lines and looks like a telescope. I feel it is reminiscent of the seaside telescopes that you used to shove coins in to use. I can only describe it as looking like a Dobsonian pier. -
I've always been a huge fan of Planewave CDK and RC telescopes and I was just browsing their website tonight and came across this picture that I just had to share with you. It features a 1 metre and two 600 mm aperture telescopes installed in Chile. What is your droolworthy telescope?
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There was me thinking "Ooh, that's a nice compact dome. I could squeeze one of those onto my patio!" It's still very nice, but no way is it going to fit on my patio.
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New Scope - an 'in between' scope
Mandy D replied to Mr Spock's topic in Discussions - Scopes / Whole setups
I started the other way, with the 8 inch first (ignoring the 10 inch which is elsewhere), then added the 4(ish) inch and now the 12 inch. OK, so my 8 inch is f/5.9, but I'm more interested in the Moon, so that suits me. Now, we both have the same quandary, having filled the gap between 4 nd 12 inch, we have two new gaps to fill! I think it is a good mix, at least for me. Oh, hang on ... I already have a 6 inch, so with the remote 10 inch, I think my set is complete! 🤣 -
I was looking into getting an EQ platform some years ago and I discussed latitude with the vendor as I wished to move it between France and southern Spain at the time. IIRC, it was suggested that the platform be design for Spain, then a wedge fitted on it for use in France. The telescope would have to be secured to the wedge to prevent it from falling over when the wedge was in use.
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If you can't reverse it, you shouldn't be driving it!
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Plastic bobbin door stops should also work well for this. I've never even considered this potential problem before as my two Dobs are nearly always used on concrete or tiled surfaces. I think the 200P has been out into the Peak District once since I got it and the 250PX did about 3 sessions away from home in the UK before it got moved to France.
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m31 on a great night wasted because I'm a numpty
Mandy D replied to Bluesboystig's topic in Getting Started With Imaging
@Bluesboystig Good luck with the Heart Nebula! -
The Nikon P1000 does not offer a focal length of 3000 mm, despite all the claims in marketing that lead you to think it does. The sensor in the camera is only 6.2 mm across compared with 36 mm for a full-frame camera like the D800. It also has a permanently attached zoom lens, which is the worst of all worlds, i.e. you cannot take it off and swap it for something else and it is a zoom which is never going to be as good as a prime lens. The small sensor gives it the advantage of producing magnified images with only a 500 mm lens (actual focal length) due to the small sensor and pixels. The small pixels mean noisy images, especially at high ISO. Yes, you can get around some of these problems by working hard, but why not make life easier and use a real camera and real telescope? Personally, I would avoid the P1000 (P900 and others in this range, too). Nikon make some fantastic cameras, but, in my opinion, the P1000 is not one of them and is expensive for what it is. For small sensor DSLRs, look at micro four thirds cameras. The beauty of these is they are built around an open standard, so lenses from one manufacturer fit and work properly on all these cameras from the other manufacturers involved. The sensors are also smaller than the crop sensors in entry level DSLRs, so make better use of available focal length, giving the equivalent of half the field of view of a full-frame camera on any given lens, or looking at it the other way (like the P1000 does) a 300 mm lens behaves on these like a 600 mm does on full frame. However, the pixels of the small sensors in micro four-thirds cameras are not so small as to cause the problems you will get with the P1000. Regarding your ultimate setup, I cannot advise what you should get, but I bought a Skywatcher 50ED to use initially as a finderscope on my big Newts, then as a guidescope for the RC6. I am now going to use it for deep-sky imaging with a ZWO ASI178MM camera. Why? Well, first because this is some of the kit I have and second because the 50ED is sharp and relatively chromatic aberration-free. It is also short focal length, so easy to mount and track with and has a very fast focal ratio of f/4.9, so requires shorter exposures than a lot of other telescopes. It is also very inexpensive at around £200 new. My mount for deep-sky is a Skywatcher AZ-EQ5 which has the benefit of being usable in AZ mode for planetary, lunar and solar, thus requiring no complicated polar alignment, but can also be used in EQ mode where polar alignment is necessary and thus allows longer exposures on faint objects. It also has a 15 kg payload which is very useful, even if you halve it for deep sky. As you can see by now, there is no single simple answer to what kit you should buy or use. It is good to see that you are attempting some astro-photography with what you have. I started out in exactly the same way with a DSLR and long focal length lenses, but then moved on to a 250PX, which is lovely, but would need a tracking platform or a humungous EQ mount for deep sky imaging. For an inexpensive, long focal length and very capable scope for planetary work I would give very serious consideration to the Bresser 127 Maksutov-Cassegrain with a focal length of 1900 mm and f/15 focal ratio. It will give a half decent resolution image of Jupiter even on a regular DSLR sensor, but you will have to shoot still frames, because of the way a DSLR captures video. To use the bulk of the sensor so that focal lengths of lenses behave roughly as they do for stills on a given camera, in video mode, the pixels are "binned", thus reducing the number of these "super-pixels" the planet will cover. If the camera offers 4k or 8k video this may not apply or not be as bad as for 1080P.
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m31 on a great night wasted because I'm a numpty
Mandy D replied to Bluesboystig's topic in Getting Started With Imaging
I concur with @teoria_del_big_bang. We learn more from things going wrong than we can ever learn from them going right first time, every time! -
Small telescope for double Star.
Mandy D replied to tico's topic in Observing and Imaging Double and Variable Stars
Yes, for splitting doubles, I agree aperture is king. I'm not as up on refractors as you are, but I have to agree that my Vixen A105M achro is very nice for stars, as is my small Evoguide 50ED, although I do love some nice diffraction spikes! If Tico's budget has to cover a mount and tripod as well, I agree the Mak is the obvious winner, otherwise the door is open for my choice of refractors as well and your smaller ones, too. My modus operandus, so far, seems to have been "go big, or go home!" I might have to change that now I'm playing with the 50ED. Good to have an amicable argument with you. -
Broken Starsense explorer tripod
Mandy D replied to Bloodline's topic in Getting Started Equipment Help and Advice
Looks like part of the screw is still in the hole and has been torque-sheared, which can only occur as a result of over-tightening or thread seizure. The latter normally only happens when unscrewing. -
Small telescope for double Star.
Mandy D replied to tico's topic in Observing and Imaging Double and Variable Stars
Oh, sorry, I must have missed where the OP said what mount this was going on. If you'd care to note, my original response offering the large(ish) long(ish) focal length refractor was prefaced by me saying "if you insist on a refractor ..." and was an attempt to show a comparison. Obviously, you think I was wrong to do this. -
Small telescope for double Star.
Mandy D replied to tico's topic in Observing and Imaging Double and Variable Stars
But 1900 mm is manageable? OK, so it's a shorter tube, but any slight wobble and you see it when looking through the scope? So, try this instead: https://www.rothervalleyoptics.co.uk/bresser-messier-ar-127s635-optical-tube-assembly.html OK, so it's over budget, but could be obtained second-hand nearer to the OP's budget. Or, go down a size, I mean after all, the frac fraternity say we can when comparing to an obstructed telescope: https://www.rothervalleyoptics.co.uk/bresser-messier-ar-102s600-hexafoc-optical-tube-assembly.html -
Small telescope for double Star.
Mandy D replied to tico's topic in Observing and Imaging Double and Variable Stars
If you insist on a refractor of this aperture that is within your budget, this one might just do it, but I cannot vouch for the quality of views you will get. It is 127 mm aperture, 1200 mm focal length. https://www.rothervalleyoptics.co.uk/bresser-messier-ar-127l1200-hexafoc-optical-tube-assembly.html -
DOES ANYONE KNOW WHAT TYPE OF STREETLIGHT THIS IS?
Mandy D replied to paulastro's topic in The Astro Lounge
You have to remember that red, green and blue work as primary colours when mixing light because of the way our eyes work, with cone receptors that are individually sensitive to red, green or blue light. The fact that we perceive certain colours when we mix these three so called primary colours does not mean that other colours, such as purple do not exist or have a distinct wavelength associated with them. You certainly would not get purple as a result of mixing red and blue light, in fact, this would produce magenta. I think you are quite right, they should have used the word "violet", though. Of course, violet light has a shorter wavelength than blue, so it's photon energy is even higher and more capable of inducing fluorescence in suitable materials than blue. In other technologies, such as flourescent tubes and mercury vapour lamps a discharge in a rarefied gas produces strong emissions in the UV part of the spectrum which is then converted to visible light by the phosphors on the inside of the glass envelope. It has been difficult developing semiconductor materials that produce the shortest wavelengths, but I think we now have some producing longer wavelength UV. If I recall correctly, silicon carbide LEDs, the first blue emitters we had, were developed at Sheffield University back in the 1990s. One of my lecturers was involved in this. -
I need to get the OTA mounted, yet. So far, I've only had it on the Skytee 2, which can barely manage it. I have plans to build a Dobsonian base out of aluminium, then later a much heavier AZ. I live on the edge of a small town a few minutes drive from the Peak District. At home, I believe we have Bortle 4. My other site in the Dordogne is Bortle 2. I have my 250PX out there and would love to take this one over.