Zermelo

Hello, welcome to SGL. One advantage of having the same true field of view at a higher magnification (i.e. the ES 24mm in your example) is that it reduces the effect of light pollution in the background sky, helping with the visibility of fainter, extended objects like galaxies. Were you particularly wanting the 82 degrees? There are the various "ultraflat" clones at 24mm/65° and 30mm/70° - for example the Stellalyra versions, or those by APM and Altair. These are very well corrected, even in fast scopes. The Superviews are cheaper, but do show aberrations towards the edges. I wrote up a quick comparison of the Altair UFF and Superview 30mm here. The 24mm UFFs are in 1.25" format, hence the limitation on the field compared with the 2" EPs. Some more discussions: https://stargazerslounge.com/topic/400497-wide-field-eyepiece-for-fast-scopes-any-suggestions/#comment-4295371 https://stargazerslounge.com/topic/403780-celestron-ultima-edge-30mm-apm-uff-stellalyra-uf/

Sounds like a good evening. I think you meant to type "M3 was underwhelming"?

The "postman" left his red van at the depot today, and instead arrived in a Caterham Super 7 to deliver these for me (accompanied by a helper). These are my first binos, so I'm looking forward to a new experience. (The BBC thinks there may be some clear spells tonight, CO says no chance)

I hadn't realized he was still with us, until I saw that he wasn't. I expect many will have heard of Moore's Law, even if they couldn't remember quite what it said. https://m.slashdot.org/story/412369

That's understandable. Start by getting to know the sky, the way it moves through the evening and changes from week to week. Even if you have the scope out on an evening, spend some time just trying to identify the more obvious constellations with the naked eye. If you have some binoculars, try sweeping the sky and see what you find. As you get to know the sky, you will be better placed to navigate with the scope and find objects that aren't as obvious as the planets. There is plenty that you can see with a 150p. https://britastro.org/2018/star-hopping https://lovethenightsky.com/what-is-star-hopping/

Unless you have really specific tastes, there's always something to look at (if the skies ever clear). What scope have you bought, and how dark are your skies? You can get some ideas for targets in this recent thread:

... or else, if no-one wants to be editing comments on a Friday evening:

I've just signed. Only 9,813 to go! I fear we are still a way off any such measures, but it all raises the profile, so thank you. (Then again, I'm old enough to remember when you couldn't expect to work in an office without breathing in your colleagues' cigarette smoke, and I never thought that would change in my lifetime)

I believe that's already in the list of requested future features, just below the flying pigs.

Send Reduced app ?

It's clear here just now, I'm not observing but I just went out back to see if the shields are having any effect on the light reflecting off the sides of the houses. It is noticeably better, so it was worth putting in the request.

An update on my recent experiences with LED street lights being fitted in my area. As I wrote in the top of this thread, all of the low-pressure sodium lamps in my road were replaced with LEDs before Christmas. Since then, I've been trying to decide how much of a difference it's making. On the one hand, the colour - while now white - is not as blue-rich as some others I have seen, and their intensity is not as bad as it could have been. I have had difficulty assessing the effect on my back garden viewing location, because of the infrequency of clear nights with no moon since then, but it seems to me now that there is a clear increase in the light spilling around the houses (reflected off walls - I have no direct line of sight view of the lights when I'm observing). We have also noticed more light coming into our bedroom. I have read reports, from other forum members, of successful applications to local councils for the installation of shielding, so I tried it myself. I thought hard about whether to mention the effect on our observing, but decided instead to lead on the amount of light coming through the bedroom window, since this seems to have been the most successful tactic in other cases. I did also say, though, that I thought the colour balance was wrong and the intensity was higher than necessary. Today, only 8 working days after my request, a van appeared across the road and work commenced. In my submission I had identified two lamps in particular that were most likely to be the source of the reflected light (and of the direct bedroom illumination). One of these was oriented "sideways" to us and the other "lengthways". An exacerbating factor for all the lamps in our road is that the bulbs were just swapped out for new ones, but the existing fittings were situated two or three inches beneath the reflector (I think you can see this in some of the photos). The inevitable result is that light can spill out horizontally, and even slightly above. I was pleased to see that the shields fitted to the two lights were selected and positioned to block the light coming towards us, affixed at the near end of the one cover, and at the side of the other: It would be interesting to see what would happen if all my neighbours also decided to make similar requests from their own perspectives - how much of each lamp would be left uncovered? After dark, this was how it now looks from upstairs: The "sideways" lamp is now noticeably less bright ... (compare it with the unshielded light on the right, which is further away). It's interesting to note that, even though the shield was obscuring all of the bulb from this viewpoint, there is still a fair amount of light escaping around it. I assume this is scattering due to the LEDs' brightness. The other lamp that is lengthways on to us has been attenuated less by its new shield: I've not been able to see what effect this has had on the light getting through to my back garden, as it's currently raining and blowing a gale. I suspect it will be some improvement, but won't return it to the levels it was with the sodium lights. So, my local authority and its contractor have been responsive to my request, for which I am grateful. The remedies seem to have made some difference, but not enough to make up for the LED brightness/spectrum. And of course, this remedial action does nothing to deal with the other light being projected into the sky by the other lamps in the neighbourhood, which is now broad spectrum. Perhaps if more people request shields for nearby lamps, it will raise the profile of the overall issue with the authorities. Meanwhile, I have had some success with my neighbour's new motion-activated searchlight (mentioned in some other post - it was impossible for me to walk to the end of the garden without it coming on). I had a word with him and he has redirected it so that I don't set it off now.

This seems to have sparked some comment recently. Something to bear in mind for future SGL imaging challenges? https://www.independent.co.uk/tech/samsung-space-zoom-fake-moon-photo-galaxy-s23-ultra-b2299947.html

I'm not sure that Ernest has a magic ruler, though.

I've just noticed, while revisiting Ernest's review of the SV215, that he has updated it (on Feb 26th) with a second review. He has now obtained a production release specimen (the original review was based on a pre-production sample). The new review is posted immediately below the original one in this thread (English, translated from Russian). He has expanded the table of nominal vs measured attributes, to cover the additional click-stops on the production model. Also, some of the measured values for those focal lengths that were included in the first report have changed in the new one. The concluding assessment now reflects the production version, and is more positive in some respects than the original review: "The glare noted in the pre-production sample has ceased to appear, light scattering still seems to me increased, eye relief is still not the most comfortable. Interestingly, the angular field of view of the eyepiece, as well as the diameter of the effective aperture, is slightly larger than stated. But the real focal length of the eyepiece (and, accordingly, the increase) at the short-focus end does not fall far short of 3 mm. ... The mechanics of the serial sample has been noticeably altered: the landing sleeve has been shortened, intermediate stops have appeared at 7 and 5 mm focal lengths, and the distance that the eyepiece extends during zooming has been reduced. The optics remained almost the same, although the enlightenment seems to have been improved. In general, the eyepiece is quite worthy to be at hand for the owner of a moderately fast telescope when observing the planets. I recommend"

I spent a week there once, really enjoyed it, but didn't see a single star.

Welcome to SGL.

Will you be imaging or visual only? There are a few discussions over on CN, for example: https://www.cloudynights.com/topic/611308-new-skywatcher-eqm-35-progoto/ https://www.cloudynights.com/topic/752028-eqm-35-vs-eq5-for-130pds-eaa/ https://www.cloudynights.com/topic/714047-skywatcher-eqm-35-pro-or-eq-5-pro-for-astrophotography-with-guiding/ https://www.cloudynights.com/topic/726414-skywatcher-heq5-vs-eqm35-pro/

Also this: http://www.deepsky-brothers.de/SinnvKombiTEL_Monti.htm

Let's call the whole thing off.

My next scope purchase might be a 10" Dob, so I was interested in the discussion of GSO's tolerances. The Stellalyra Dobs don't quote any, and I found quite a few other GSO ads that didn't specify. But this one does quote "Diffraction Limited Optics (1/12 Wave RMS)", and the GSO mirrors sold here say "1/16 wave RMS at least, and often better" (I'm not sure how "better than 1/16 wave" helps, if 1/12 wave is already diffraction limited). I'm also aware that unqualified statements like this are ambiguous at best. Does anyone have any definitive info on GSO mirrors? Do the same tolerances apply to all of their output, or do they vary?

FLO do sell the 150PL on an EQ3-2, so it's obviously not an unreasonable match. The performance of increasingly heavy OTAs on a specific mount does not have a sharp transition from "OK" to "not OK", it's a gradual decline. I couldn't see a weight on FLO for the 150PL, but elsewhere it's quoted as 5.9kg. The stated max for the EQ3-2 is 5kg, so it's pushing it. And that's before you start adding a Telrad, better optical finder, heavier eyepieces, etc. The other factor with the 150PL is its length. It has a greater moment of inertia than a shorter OTA of the same weight, which affects its stability on a borderline mount. It also makes it more vulnerable to disturbance from wind. Obviously you just need to try it on your mount first a few times, especially in a breeze. A 6" F/8 is a classic configuration and a good all-rounder, and for visual only, you may find it works for you. If you need to get a heavier mount, you might be better off looking for a second hand EQ5.

oooh, now there's a challenge https://warwick.ac.uk/fac/sci/maths/people/staff/robert_mackay/isostaticmount8.pdf

Hello, and welcome to SGL. To get useful responses, you will need to say a bit more. How much do you want to spend? Do you have any prior observing experience? Have you done any research to identify the kind of scope, or features that you are interested in? Will this be for visual use, or for photography? Will it be just you using it, or will you be observing with anyone else? Do you have somewhere convenient to store it, and will it be easily transportable to where you will use it? (i.e. not down three flights of stairs) Do you think you will be using it away from home much (i.e. do you have decent skies where you live?) Do you have any other constraints?