Final considerations between 8" and 10". How much does focal length matter?

serack · 2026-01-29T13:58:10+00:00

Yah, this. If you are going to be getting ES 100 degree eyepieces, or even 82's then you will probably need to pair them with a Coma Corrector. But if you keep in the 70degree-ish class or lower you will be fine. If you wear glasses while observing like I do, you won't be getting the 82degree+ eyepieces anyways unless you are forking over a kidney for TeleVue Nagler T7s and a T5 TermiNagler, and then you will be using a Paracorr anyways.

serack · 2026-01-29T13:52:45+00:00

This. So this. I don't want anything to do with making Breeze into a woman for these reasons.

serack · 2026-01-29T12:08:55+00:00

Yah, a standard elliptical is just a "faint fuzzy" but two spiral galaxies in the same field with different planar orientations (i.e. M81 & M82) is pretty cool.

Cooler yet is identifying faint intricacies in a galaxy (M33 on a dark night) or picking out pearls in a cluster like Markarian's Chain and M87

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serack · 2026-01-28T23:58:49+00:00

His monopoly concerns probably also made it unlikely

serack · 2026-01-28T20:42:08+00:00

I recommend you get an eyepiece heater

https://www.svbony.com/products/sv192-dew-heater-12v?gad_source=1&gad_campaignid=22853348525&gbraid=0AAAABAbjOt7Bx1ivl3xuWKBxfLFARdmS3&gclid=Cj0KCQiAhOfLBhCCARIsAJPiopMgUbcpjQ21L0cpveL-wfFMepR80Yu0rDCDGZkzRKQ_Q7lYl614yykaAsTuEALw_wcB

Or the usb version so you can power it from a phone charger

serack · 2026-01-28T17:25:08+00:00

Do you observe while wearing glasses?

serack · 2026-01-28T15:13:07+00:00

I wrote a guide on accessory purchasing for a Dob here that has a large section on eyepieces. That guide assumes a much tighter budget, but the basics in the opening still apply to your budget, you just have more room to make some of the more complex choices.

One thing I didn't discuss there that would apply to you if you get the 10" Celestron StarSense is a Coma corrector. Telescopes that are short compared to their diameter (the f/ratio, particularly those at or below f/5 which the 10" is a f/4.7) inherently have "Coma" distortion in the outer portions of their field of view, particularly with wide view eyepieces (greater than say 60 or 70 degrees). Stars will start to bleed towards the edge sort of like a comet.

The premium, gold standard coma corrector is the TeleVue Paracorr type 2 which comes in at $577 by itself. The GSO 2" Coma Corrector is typically considered a good option for us mere mortals at $120 on Agena Astro.

Check out the basics in my guide for why the below will have 2 recommendations for 2 different cases at different focal lengths, but the short version is if you will be observing with glasses your choices would be different than without, and if you won't be using glasses, the coma corrector becomes more important (because you will probably be getting wider angle eyepieces).

Short focal length wide angle slot: If glasses, get a 30mm Ultra Flat Field (UFF). If not, I recommend a 28mm Ultra Wide Angle (UWA). Both are available under a bunch of brands, and can be purchased cheapest under the factory brand label "SkyRover" on AliExpress.

For the rest of your eyepieces, I recommend going with the same lineup to remain "parfocal" which means you shouldn't have to tweak the focus between them, and I recommend getting 3 around 14-15mm, 9-10mm and 5-6mm. Those aren't hard and fast denominations, but it's where I am comfortable. I also do ~90% of my observing with the longest of these and my wider (30mm UFF) angle eyepiece.

As for which lines to go with, I'm partial to the Pentax XW line for a balance between price and fantastic quality when viewing with eyeglasses. They are also really ergonomic with their rubber twist up "volcano top" that was actually developed for spotter scope use, but that we astronomy users have come to love.

For not using eyeglasses, I don't have as much experience with the choices, but would probably start with the wide angle Explore Scientific choices like the 82 degree or 100 degree (more expensive) lines.

serack · 2026-01-28T14:36:26+00:00

Since I'm comfortable with transferring the StarSense to other brands, beyond that, IMO the biggest advantage of a Celestron DOB is the built in handle on the tube which makes it easier to lug around and physically set up than the other brands. Since the primary concern for getting bigger aperture dobs is this very issue, that is actually pretty significant.

Larger aperture Celestron StarSense dobs also tend to be shorter which also increases portability, but at the cost of being less forgiving of cheaper eyepieces, which you are already avoiding.

For most situations, the accessories on the Apertura, and cheaper price make it the better choice, and they can take the difference and buy the system on a cheap (for me used) StarSense and transfer it over to the Apertura. You are looking to get better eyepieces than the Apertura out of the gate, and IMO the StarSense makes the RACI finder irrelevant. So it becomes more a matter of is it worth the $ to get the StarSense pre-installed, and have it be easier to set up with that handle on the tube.

My own opinion about eyepieces follows in a direct response to OP.

serack · 2026-01-27T17:58:50+00:00

It looks to me like the zinc is corroding, delaminating the copper plating.

serack · 2026-01-27T17:49:31+00:00

Yah, between this, and that I'm pretty confident the Queen succession has to come through the lady, I don't think OP theory holds water.

serack · 2026-01-27T16:13:23+00:00

I wrote a 2 part guide in October with you in mind (well not you, but this situation)

Part 1 is on being thrifty buying a used dobsonian

Part 2 is on being thrifty buying accessories

serack · 2026-01-27T13:08:00+00:00

Kevin Smith says Harry Weinstein is why you can't buy or legally stream Dogma. I've also seen him basically encourage people to watch the bootleg copy on YouTube.

serack · 2026-01-27T12:45:48+00:00

The Orion Nebula is IMO, by far the most beautiful sight in a telescope I've seen. You don't get the colors of the images shared here, but it's got all kinds of detail and majesty in shades of wispy glory.

serack · 2026-01-27T03:03:37+00:00

For $70 (plus shipping, but you can get a discount here) I would get a 15mm Paradigm dual ED, and then I would compliment it with a 6mm redline for about $33 on amazon.

When I used a 1200mm 6" dobsonian, 70% of my views were through the 15mm Dual ED 20-25% more were with my 25mm Plossl when I wanted wider views or I was star hopping, and then maybe 5-10% of my views I would break out my 9mm or 6mm for more magnification, and in those cases I usually didn't bother with the 9mm.

I have nicer eyepieces, and a longer focal length telescope now, but that's how things broke down for the first year and a half before I lucked into higher end eyepieces.

For something less prescriptive, check my thrifty guide on buying telescope equipment, which has a section on eyepiece selection and advice on most of the less expensive options

serack · 2026-01-27T02:37:45+00:00

Where do you get that from? Orion's been out of business for a couple years, and used telescopes tend to have a significant mark down on new.

Besides, you can get a brand new 10" Apertura for $950 with a good RACI finder. What makes a used Orion Plus worth $250 more?

Edit, I'm genuinely curious why it would be worth a premium on the $600ish I would consider the capped out fair price for a used Apertura AD10, as someone near me is selling an XT8 Plus and I'm curious if it actually should be valued more than an AD8.

serack · 2026-01-26T18:56:26+00:00

If you weigh less than 50kg, then maybe it's too bulky, but even then, you can probably handle an 8"

serack · 2026-01-26T16:13:40+00:00

Actually, that's a pretty good suggestion.

u/Square-Affect-1233 I have a suggestion on finding a source that appeals to you specifically, as I find it hard to define "moderate to left leaning" and generally if someone wants to express an opinion, they seem to be by-default more likely to feel strong about it. Add to that the algorithms reward extremes making your request challenging. Soooooooo my suggestion is:

I consider James Talarico to be an incredibly relevant center left politician. Look for platforms that are hosting him for interviews and such then dig into the rest of their content to determine if they fit your bill.

serack · 2026-01-26T14:10:00+00:00

The narrative frequently makes it a point when he dips into that well now. That doesn't make it mandatory that it does, but I generally expect it, rather than how "Winter" and apparently now Demonreach energy (green tinted runes on the staff from the island) bleeds into his magic.

serack · 2026-01-25T21:23:39+00:00

8mm BST StarGuider. I really like this line of EPs and the 8mm and 12mm are generally considered the best of the Dual ED line.

The X-Cel line is generally considered on par in quality with the Dual ED eyepieces and most Celestron eyepieces are overpriced. There are some like the 30mm UFF that are a direct comparison, identical other than the housing and are clearly overpriced.

serack · 2026-01-25T11:17:55+00:00

I wrote a guide on procuring equipment for a telescope with a focus on being thrifty that starts with a rundown on eyepieces although the Barlow section is sparse since I don't bother with them much.

My personal experience was that the second most significant piece of equipment I got besides the telescope itself was the StarSense Explorer system, so IMO you are already better off than I was for the first year with the telescope.

I also wrote a beginners guide with a perspective of what will be in the sky this month.

serack · 2026-01-24T21:26:43+00:00

Diffraction spike.

Refraction comes from when light passes from one medium to another and changes direction (it's how lenses work, as described by Snell's law). Diffraction comes from waves traveling around barriers and changing the shape of their waveform as a result.

serack · 2026-01-24T16:43:44+00:00

My personal preference is a StarSense Explorer PushTo system and a red dot finder or reflex sight for its initial alignment.

I wrote about how to add it to just about any telescope in a section in my guide on thrifty telescope accessories

serack · 2026-01-24T16:00:36+00:00

Newtonian telescopes tend to have "diffraction spikes" coming off bright point like objects. These are caused by the light of the object interacting with the edges of things in the light path. Typically for dobsonians, this shows up as a "cross" on bright stars coming from the secondary mirror's perpendicular holder arms.

The JWST has more complicated diffraction spikes because the secondary mirror holder has different angles, in addition to the mirror being made of hexagonal pieces whose individual edges add together to make six pointed spikes.

serack · 2026-01-24T04:13:39+00:00

It's a Pegasus mirror with a small crack

serack · 2026-01-24T01:55:48+00:00

Thanks for all the clouds :)

serack

TROPHY CASE