DanielC

Thanks for all the help guys! This is very helpful. I'll follow @Second Time Around's advice and get a zoom eyepiece, and I'll follow @John's advice and add a low power eyepiece for wide angle. I haven't bought the telescope yet because it's out of stock, but I'm planning to get a Celestron NexStar 6SE. So if the zoom shows a good image at 8mm and it looks stable enough, I could add a 6mm later. But I'll first wait and see how the zoom works out. Thanks again!

What are your thoughts on zoom eyepieces? In what situations do you think they're a good option vs fixed eyepieces? For example, I know that zoom eyepieces typically have a smaller AFOV than fixed eyepieces. Is that their main disadvantage? I read online that zoom eyepieces can be great for planets because there's usually one particular magnification that really works a lot better than the others in terms of making features large enough while still having enough contrast, and that. Looking at prices, I'm thinking that if you just get a zoom eyepiece you can spend more money on it than if you buy several fixed ones. For example, for a $200-$250 budget I could either buy... Four Orion Expanse Wide-Field 1.25" Eyepieces, OR Three Orion EF Widefield 1.25" Eyepieces, OR One Orion 8-24mm Pro Lanthanum Zoom Eyepiece, OR One Celestron 8-24mm Deluxe Zoom Eyepiece. To my inexperienced eyes, it looks to me like I can a cool and fancy zoom eyepiece for the price of 3-4 regular eyepieces and I'm trying to figure out if that's a good trade. Thanks for the help!

Thanks. Can you help me understand this? For the SCT that I'm planning to buy, the focal ratio is F/10 so the exit pupil is pupil = (focal length of eyepiece) / 10 So the 40mm eyepiece would give me a 4mm exit pupil and the 32mm eyepiece would give me a 3.2mm exit pupil. So I googled for "exit pupil" and I saw that apparently a larger exit pupil means that there's more light going into your eye. But I don't understand that. If both eyepieces are already at the maximum field of view that the telescope can produce, aren't they both giving me every last photon that the telescope can collect? Thanks!

Thanks!

Let me add that Jupiter and Saturn are actually difficult targets. I know everyone wants to see Jupiter and Saturn, but they're tiny and it's hard to see anything besides a small fuzzy circle. In general, planets are hard because they're small, and nebulae are hard because they're dim. The easier targets (after the moon) are globular clusters and binaries. Go back to your friend and ask him to show you some of these: 1) Double Double -- it is a 4-star system (two binary stars in orbit around one another). 2) Mizar & Alcor -- binary in the Big Dipper; if you zoom in you'll see at least one more star. In truth, Mizar & Alcor are really a 6-star system. 3) Albireo -- a beautiful binary; one bright red and one dimmer bluer star. 4) Great Cluster in Hercules -- globular cluster Then you'll have more information about what's possible with a telescope.

I don't know your area, but here's a light pollution map: https://www.lightpollutionmap.info/#zoom=5.10&lat=6590529&lon=-151987

I am no expert, but I'll jump in because I also set out to find a 6'' reflector. The problem that I found is that an eq2 mount would be unstable unless you spend a fortune on a very solid one. A dobs would be stable and cheap. In the end I didn't go that way because my partner didn't want a dobs because they're bulky, so we decided to go for an SCT instead of a reflector. The SCT costs more money than a dobs, but not as much as a reflector with an eq2 mount strong enough to hold it steady. For a 6'' = 150mm aperture we get: FL = 1200 --> focal ratio = F/8 FL = 700 --> focal ratio = F/4.67 I have been advised that a focal ratio around F/5 is very difficult to use because the image goes out of focus very easily, and you may need to spend a lot of money on an expensive eyepiece just to get the F/5 to work. I have been told that it's better to go for a longer focal ratio (so in this case, F/8) because it's easier to use and a less expensive eyepiece works just fine.

Hi everyone. I'm trying to pick a wide field eyepiece and I'm looking at these two: 32mm Meade Series 4000 Super Plossl 1.25" Eyepiece, AFOV = 52.0° 40mm Meade Series 4000 Super Plossl 1.25" Eyepiece, AFOV = 44.0° I plugged both of these in the Field of View Calculator, paired with a Celestron NexStar SE6, and they seem to have a near identical field of view: So... what's the difference between a 32mm with a 52° AFOV and a 40mm with a 44° AFOV? If they cover the same real field of view on the sky, wouldn't the 32mm with a 52° AFOV appear larger when you look through the eyepiece? I thought that a 40mm would always look more zoomed in than a 32mm but maybe it's not that simple. Can someone clarify this for me? And also, in this example why would anyone choose the 40mm over the 32mm? It looks worse in every way. Thanks for the help!

So a few days ago I decided to buy a Celestron NexStar 6'' but since they're out of stock right now, I'm aimlessly skimming over telescope websites and I saw that Celestron has two other telescopes that seem to be closely related to the NexStar: NexStar 6SE ($800) SkyProdigy 6 ($1,000) NexStar Evolution 6 ($1,300) Can anyone help me understand what the other models have that make them more expensive and whether the price is worth it? As far as I can tell the specs of the OTA itself are nearly identical. But there seem to be several differences in the mounts: SkyProdigy says has a "fully automatic alignment procedure" and you can see a little camera attached to the mount. From the description, it seems to me like the SkyProdigy uses that little camera to take various pictures of the sky to orient itself. That's cool I guess. SkyProdigy seems to have a flimsy mount: 8 lbs capacity (exactly the weight of the OTA!). The tripod weighs only 5 lb. For comparison, the NexStar holds 12 lbs (tripod weight = 9 lbs). Conversely, the Evolution is sturdy: 25 lbs capacity (tripod weight = 11 lbs). Evolution has built-in wifi, integrated Lithium-ion battery, and two eyepieces instead of one. So... the SkyProdigy looks flimsy which is weird for a more expensive telescope; and the Evolution looks great, but is the difference really worth another $500? Is there anything about these telescopes that I've missed that help justify their prices? Always grateful for any help.

What is your idea of "space science"? Building rockets and satellites? (i.e. space engineering) Observing galaxies and nebulae? (i.e. astronomy) Moons of Jupiter, craters, etc? (i.e. planetary science) How good are your grades? Are you good at math and do you like math? I am not familiar with the Indian school system. What is 12th science? Let me start by saying that all the things I listed (astronomy, planetary science, space engineering) are all things that India does, but they are all small fields and very competitive. So in all cases the strategy would be to pursue a career in university that gives you the opportunity to go into those disciplines but also keeps options open in case that plan doesn't work out. This won't be difficult at all because all the things that truly specialize those disciplines are things that you'd learn later in your career. The main goal should be to keep doors open: In all cases you would need to study math and classical physics. Very important. You have to either teach yourself how to program or take a course. Try to find a course targeted toward science students rather than "computer science". If you want to pursue space engineering you need to look into engineering courses. If you want to pursue astronomy, some astronomy courses would be helpful. If you want to pursue planetary science, you might want to take a geology course, and at least first year chemistry. If you give me more details, I can help you more. I am an astronomy postdoc at a university and I'm familiar with some of the options.

Ok. Dew shield. Is a light pollution filter a good investment or is it a waste for money? I live in a suburban area, and I won't be doing astrophotography. EDIT: I just thought of another question. Do you collimate SCTs? Or is that something you only have to do for Newtonians?

Perfect. I'll get this one. I saw it earlier and I liked it. I had ignored it because I had it in my mind that Newtonians were always the best value for money. But now I see that it's not so simple. The drawbacks of the NexStar 6SE look like things that I can handle better than the drawbacks of the reflector. Not getting a wide FOV is unfortunate, but not as bad as a shaky mount or low quality components; and I still have my binoculars. To deal with the dew and cooling time, I will keep the telescope in my garage, or I'll make sure to bring it outside early. Thanks for all the help!

After spending the last few hours trying to make the 6'' reflector idea work, I don't think I can stretch my budget that far. So I'm ready to consider a lower aperture and longer focal length. You gave the example of a 127mm Mak. What can I expect from an instrument like that? How do I know if I'm looking at a quality instrument? The first 127mm Mak that I found has a focal ratio of F/10. https://www.telescope.com/All-Telescopes/Orion-Apex-127mm-Maksutov-Cassegrain-Telescope/rc/2162/p/9825.uts Using the field-of-view tool that @vlaiv suggested, and seeing that the above telescope comes with a 25mm eyepiece with a 52deg FOV, it looks like it would work well for several Messier objects including the Crab Nebula and globular clusters, but the FOV is too small for the Orion Nebula. If I add a 6mm eyepiece I'll see Jupiter's moons, but I'd need some luck and/or a filter to see a band on Jupiter. I think I can work that that. I need to think a little more, but I am persuaded that a small high-quality instrument is a better investment than a large poor-quality one. You said that a 127-130mm Mak is an instrument I one would keep even after graduating to something bigger. What would you do with a 130mm Mak if you also have a 150mm telescope? Do you have smaller telescopes that you often use? Thanks for the help!

Ah! This is all very helpful. Yes, I remember being very frustrated in the past with shaky telescopes. Thanks for catching that! Yeah, back when I had my small table top telescope I learned how to collimate it. It never occurred to me that a $550 telescope would not have collimation screws. I thought it was standard because my little $50 table top had them. That's also very helpful. I will aim for an F/6 then. Going in the other direction, how much focal ratio is too much? I just saw a Maksutov-Cassegrain with F/15. I know that if the focal ratio is too high you end up with a small field of view so it's impossible to see wide things like the Milky Way. I am looking for a general purpose telescope that works fine for "everything". One day I'll try to see Saturn, the next day I might want to see the Pleiades. Good to know. I will look for alt-az mounts then. I liked the iOptron mount that you suggested. I'll try to find something like that here. Thanks!

Thanks for all the help! From what you are saying, it sounds like I might need to revise my budget and maybe also pick the components myself rather than grab a pre-packaged set so I don't get stuck with a crappy mount and crappy eyepieces. Can you explain a little more what an "under mounted scope" is? What are the downsides of a basic model compared to a higher quality one? I want to make this choice carefully because if I end up throwing away the basic model and buying the expensive one anyway then I wasted my money. You mentioned that the heavier mount would be more stable and I definitely see how that is very important. Is that the main difference? You said the other mounts you suggested were overall better quality; so what else would be different about them? Likewise, what are the advantages of the OTA you suggested? Is it mainly that it will have better optics? I can see that it has a 2'' focuser so I could buy a wider field eyepiece and take a huge picture of the galaxy. I think I can find components similar to what you suggested: 1) OTA https://www.telescope.com/All-Telescopes/Orion-6-f4-Newtonian-Astrograph-Reflector-Telescope/rc/2162/p/116530.uts This is a 6'' Newtonian reflector that looks very similar to the one you suggested. I found it in the "Astrophotography" page. 2) Mount -- version 1: equatorial, not GoTo https://www.telescope.com/All-Telescopes/Orion-SkyView-Pro-Equatorial-Telescope-Mount/rc/2162/p/9829.uts This mount says it can handle 20lbs and the telescope above weighs 12.7 lbs. So I guess it must be a sturdy mount. But there is no GoTo. 3) Mount -- version 2: equatorial + GoTo https://www.telescope.com/All-Telescopes/Orion-SkyView-Pro-Equatorial-GoTo-Telescope-Mount/rc/2162/p/24709.uts This is the same mount as before, but with GoTo included. 4) Eyepieces https://www.telescope.com/All-Telescopes/Orion-Expanse-Wide-Field-125-Eyepieces/rc/2162/e/55.uts I don't know anything about eyepieces, but these ones say 4-5 elements (why do I care how many elements it has?), the opening looks much larger than the cheap eyepieces I saw earlier, the eye relief is 15-18mm which sounds like a lot to me. Do these look similar to your suggestions? Let's see... my initial suggestion was $550 and the combination above would be $800 - $1,200 depending on whether I get the GoTo. I also found an 8'' Dobsonian alternative for about the same price. So I need to take this information and think a bit more. Thanks for the help!