The Coulter 10" f/4.5 Dob Review - A Classic Retro Dob in 2024. How Does it Fare Today?
ฝัง
- เผยแพร่เมื่อ 28 ส.ค. 2024
- Do you have any memories of old Coulter Dobs?
Amazon Affiliate Links:
Orion Observer 134 Telescope amzn.to/3DF1c59
Orion Starblast Telescope amzn.to/3N3GYp9
Zhumell Z114 Telescope (same as the Orion Starblast) amzn.to/363jVdH
Orion XT6 Telescope (new version as of 2022) amzn.to/3z4TBuz
Orion XT8 Telescope (new version as of 2022) amzn.to/3FN54SX
Sky-Watcher 6” Dobsonian Telescope amzn.to/3CXUZAi
Sky-Watcher 8” Dobsonian Telescope amzn.to/3wkAQmt
TeleVue 24mm Panoptic (my favorite 1.25” eyepiece) amzn.to/3NtKHwl
TeleVue 13mm Nagler Type 6 eyepiece amzn.to/3t248F4
TeleVue 7mm Nagler Type 6 eyepiece amzn.to/31xtq2q
TeleVue Everbrite 1.25” Diagonal amzn.to/3JWEveT
TeleVue 2X Barlow (Much better than the cheap throwaway barlows found in cheap scopes) amzn.to/335DAaI
Heated gloves amzn.to/2R45aiW
Heated vest amzn.to/3nVoefs
Small planisphere amzn.to/2JAGvyK
Large planisphere amzn.to/3qsiRFh
The Cambridge Star Atlas amzn.to/3mDAakC
The Stars: A New Way To See Them amzn.to/3lvEUaA
Sky & Telescope's Pocket Star Atlas amzn.to/2VrcDrb
The 21st Century Atlas of the Moon amzn.to/3bsk4Hk
Turn Left at Orion (good beginner’s book about finding stuff) amzn.to/3fYPRQQ
My tiny 8X21 binoculars are here amzn.to/39RdfyP
A decent pair of 7X35 binoculars amzn.to/3mESBoV
A decent pair of 7X50 binoculars amzn.to/3g6amLB
The Orion 8X42 binoculars are here amzn.to/37vW1UK
Camera used for filming amzn.to/38QrkLv
Camera I’m using for 4K video and some B-Roll amzn.to/3D1pOmk
The lens I use for filming (80% of the time) amzn.to/38QIN6i
The lenses used for filming the rest of the time (17-40 f/4 and 24-70 f/4) amzn.to/3cITdpV and amzn.to/3ns4cck
My tripod amzn.to/2OEDhNo
My ballhead amzn.to/3cLeLSW
The softboxes I use amzn.to/3qSDp91
Wireless mic: amzn.to/3tQcRHv
My astrophotography book contains advice on telescopes observing, and taking pictures (based on my award-winning Dartmouth thesis, June 2020) 255 pages, 258 color images: amzn.to/2Jt1O5o
Top Three Recommended Beginner’s Telescope Video: • Top 3 Beginner's Teles...
Top Beginner’s Astronomy Books: • Top Beginner's Astrono...
For Complete Beginners, Part 1: • Getting Started in Ama...
For Complete Beginners, Part 2: • For ABSOLUTE BEGINNERS...
Hundreds of other telescope reviews on my web site at:
www.scopereviews.com
Babe wake up Ed ting posted a video
Ed, you’re one of the very few channel creators on YT whom I’d call erudite.
In the late 80’s one of my observing buddies had a blue 13.1” Coulter. He used it a LOT - often with the version 1.0 13mm Nagler.
He’s gone now. May he rest in peace. One night he came along with info on NGC 2419 - the intergalactic wandering globular cluster. We each tracked it down with our respective scopes - as always having a grand old time. Before I met him he had a C-8 and did astrophotography out on frozen Lake Ontario. He joked - not far from the truth - that he had no need for a “cold camera” out there at forty below. And he was out there at forty below.
I love your channel. Thanks a million for giving a rather prosaic relic its time in the sun.
I used a Meade ultra-wide 82 degree 14mm eyepiece exclusively on my 13.1" Coulter. Perfect all-around eyepiece for that scope.
Coulter brought aperture to the world of amateur astronomy... The first time I saw M51 through a Coulter 17.5 inch I was in shock.
what did it look like?
I bought my Odyssey 13.1 inch dob back in 1980 for $300! The best money I have ever spent. I had to wait a year for delivery due to backlog. I hauled that baby to dark sky locations for over 25 years, including a 4X4 trip to Moab Utah. Yes, it was a simple inexpensive telescope, but it was functional and durable. The mirror was slightly less bright when compared to a Galaxy 12.5 inch mirror, but given the price difference, the views from my dob never disappointed. I made a stop-down mask to observe the planets and observed comet shoemaker-levy impacting Jupiter. My buddy and I could visibly see the black impacts from the comet fragments! It was a good scope for the price! Great to see this "ole" girl in such great shape! Brings back wonderful memories, thanks Ed!!!
i want to experience that magic
@@marcov9808 I hope that you do! Find the right size scope that fits your lifestyle, and you won't be disappointed. It's a wonderful hobby and pursuit.
@@ToddHurney I just bought an 8 inch dobsonian 2 days ago and I've out every night. I need to learn how to target DSO's i have a hard time even remotely finding where to point the scope.
@@marcov9808 If the scope came with a right-angle finder then that's probably what's contributing to your difficulty. I replaced my right-angle with a Telrad and it makes life trying to locate objects much, much easier, because you are looking at the night sky while you move the scope instead of staring at your optical tube! You still need to have star charts, a red light to keep your night vision and some training learning the night sky. Learning the constellations and major stars isn't that difficult but requires some time and effort. Once you feel comfortable with the major constellations and bright stars, then pull out your star charts and begin with the popular Messier objects. Take it from there! Enjoy! If you can purchase or locate a Planisphere it will take a lot of the guess work out of what you're looking at in the night sky. Planisphere's are great hands-on devices that I used to teach myself the constellations. Have fun!
@@marcov9808 I believe I already responded to your inquiry, but just in case here's what I suggest. Back in my younger days there were books called Star Atlas's that had all the NGC (New General Catalog) and all the Messier objects and their locations in the night sky. Now you can just download one off the computer. I used a Planisphere to learn the constellations as well. If you can pick one up, they are quite helpful. The last thing you'll probably need to purchase to make finding objects easier is a reflex finder like a Telrad or similar product that allows you to see what you are looking at. I hate right angle finders. Learn how to "triangulate" using the stars depicted in your atlas. It just takes some time and practice. Before you know it you'll know the constellations and where your favorite objects are-just take it from there! I hope you're enjoying the new scope and hobby! Happy observing!
Thanks Ed for doing this very nice review of a very old classic dob. I’m a member of the Coulter Cult. My 13” Red Tube sports a 2 speed 2” crayford focuser, a green laser pointer, telrad finder, a counter weight on the aft end for balance, a bar stool cloth cover for an end-cap, a new dolly with 6” locking wheels and finally - a reverse-engineered StarSense bracket copy using Celestron’s plate solving app. I wish I could show you a photo. When I wheel it out of my garage, it’s like moving a Saturn 5 rocket to the launch pad. Her name is “Big Bertha - United Federation Starship”. It’s a galaxy class starship. Love my Coulter! Thanks for all of your great video reviews Ed!
I had a Odyssey 17.5 inch. It was huge! And heavy. I needed help to set it up. The views were spectacular. I bought it used in 1992 and it had been modified. It had a smaller secondary and a spider to hold the secondary. it was not made to remove the mirror for storage/travel. I rebuilt it into a truss telescope and I could set it up by myself.
I could see the California nebula w/ an Oxygen filter., and 11 moons around Saturn.
Hey Ed, Glad I found your channel! I remember the Planetarium had a 13.1 Coulter that we used in an Astronomy class I took thru UNH back in the 90s.
I had the 13.1" in 1982. I Ioved it. It was a huge revolution when most of us where using 6" scopes. It was hard to move to the observing site, but damn it was easy to use. It was much smoother than any newer dob I have used. And the optics were good! I had a red one later, and it wasn't nearly as good.
The earlier Coulter mirrors from the late 70's early 80's were better configured. These scopes with their large light gathering power and low cost revolutionized amateur astronomy. If you were teenager such as me in 79 and wanted or drooled over a 10" Cave Astrola or Celestron C-8, you either had to have generous wealthy parents or you had to wait for a much better paying job. Coulter made big aperture affordable. I never regretted purchasing my 13.1" in 1980. It simply was the best $300.00 I have ever spent. I got a lot of use out of that scope.
@@ToddHurney I got mine in 1982, aged 20. I wish I still had it.
Such a beautiful telescope.
A great look at a classic. Coulter rode the wave of interest in Dobs and big aperture observing that started in the 70s. Before Coulter if you wanted a big Dob you had to make it, likely grinding your own mirror from porthole glass, such as John Dobson did. The early Coulter Dobs like the one you tested were copies of Dobson’s original design. I was at the Riverside Telescope Maker’s Conference in 1980 when Coulter owner Jim Jacobson (?) unveiled the 13.1 inch. A photo is on p. 127 of the current edition of The Backyard Astronomer’s Guide. I bought one shortly after, picking it up at Coulter in Idyllwild, CA, and using it for the first time at the campsite in Mt. Palomar! I remember Jim asking if it would be possible to see all the NGCs in a 17.5-inch, then in planning or with advertising starting - he wanted to know what they could claim you could do with an even bigger scope! I think I said yes? The odd mirror sizes I think were a result of maximizing the number of round disks you could cookie cutter out of a sheet of glass.
Thanks, Alan. The owner of this 10" says he looked through a 29" and saw subtle blue and red coloring in the Sombrero.
Our Astronomy club "Texas Astronomical Society of Dallas" recently auctioned off 2 of these in the 8" range, one was a red-tube with a helical focuser the other was blue. They both sold at our club auction for under $100, one going for less than $50
Thanks Ed. Your scope reviews are always informative and enjoyable. And also the source of 99 percent of my current scope knowledge. Looking forward to you next video.
I've wanted to re-coat and maybe re-figure the mirror on my 13" red tube coulter for a while now.
Man, I love these reviews and explanations. These are just the best on the whole internet.
Bought a Coulter 17.5" mirror set circa 1979 or so when they first came out, before Coulter sold completed scopes. It was a REVOLUTION in US amateur astronomy. Sold the mirror, still have the secondary, my biggest is a mere 10" f/7 made by Edmund on an Astrola equatorial mount.
I like these reviews of the older newts! I know what you mean by not wanting to haul heavy scopes out and in. The 13.1" rarely makes it out of the garage...
That's a shame, but I understand. It's a lot of scope to load and unload all the time. When I would take mine out into the field I would have people pull over and ask why I had set up a big red water heater out in the middle of nowhere!
@@ToddHurney LOL! I can see why they'd ask that! 😂
I remember drooling over those Odyssey ads, but never had the $ to buy one. Still a fond memory.
I recently picked up a 13” coulter from my astronomy club. The OTA and rocker base were in rough shape the the optics were good. I’m planning on building a truss frame dob for it.
My first real astronomical telescope was a red Coulter Odyssey 8”, purchased around 1990, with an eyepiece from a cheap pair of binoculars mounted in a piece of PVC tube. I put a serviceable focuser from University Optics on it (I think it was a threaded 2” model) and happily used it for around 6 months. I then sold it and bought a Celestron/Vixen C80 on a Super Polaris mount. While the images weren’t quite as bright, the improvement in sharpness and contrast blew me away. With a very few exceptions (including, very briefly, an 18” Coulter!) I’ve been a refractor guy ever since.
I bought a 13 and 10 red tubes last year off Craigslist in a package deal. 13 was not sharp on moon or planets but ok for galaxies, nebulas and brighter large clusters. Never used the 10in.
They have been recently replaced with a 16in Starfinder Dob I got for $500.
I remember those adds in Astronomy magazine from years ago early 80's .......................I'm getting old .
Very cool! I have a 10" red from 1985 still in the basement. Only mod was a Telrad. No rocker box by then. Need to check az - it was always pretty smooth. Definitely need to clean it up and give it some light.
I always enjoy your reviews.
My Coulters include: The 4" 'Coffee-Can scope,' a 13.1 mirror that I ordered in 1989 and received 36 months later(!) which I housed in a truss travel scope of my own design that I've taken to Hawaii twice and Chile once, and a 17.5 that was the old blue version that I bought from a club member in 1989 and immediately remade into a truss-Dob. The latter was my main scope and I regularly observed with friends (Steve Gottlieb and Jim Shields--well known observers) that had Galaxy or Zambuto 18-inchers: I kept up just fine. Steve and I hunted down most of the 100 Hickson Compact Galaxy Groups together--and traded views all the time, for example. . . Sure, I own Zambuto mirrored scopes now (10, 12.5, 18) and a plethora of APO's, but I'm not gonna throw any shade on Coulters.
I bought the (used) collapsible 'Coffee-Can' scope from a vendor at Riverside TM Conference around 1993; I had to ask what it was before I plopped down the money, as I had never seen one before. Later that weekend, I was standing in line to look through a 40" scope and sparked up a conversation with the guy right in front of me who happened to work for Coulter; he was, in fact, the foreman of the woodshop (in Tecate, Mexico, BTW) where the structures were made. He told me lots of stories: Everybody at Coulter loved the Coffee-Can scope, but they could not make money on it, so it was discontinued. Was it their first scope? Maybe, I don't remember. He said the owner Jim Jacobsen (sp?) had a huge contract with Meade, bought a bunch of expensive optical machinery to gear up, and then Meade backed out. Jacobsen then started making big Dobs with all this equipment. John Dobson's designs revolutionized visual observing: "Nothing beats aperture," as the saying goes: Coulter was the first to capitalize on this while remaining close to Dobson's vision of an 'everyman's scope'--an affordable scope for the masses, in other words. Others followed suit. And when did Al Nagler come out with his revolutionary Naglers? These eyepieces were designed with the fast Dob in mind, which simply did not exist before Coulter.
Right On! Couldn't agree with you more.
I plan on keeping a eye out for 1980's odyssey telescopes and grab them puppies up right quick!!!! Another great video!
I've had the same scope on 2 occasions! Decent scope! I call them 10in cannons!
That scope is in amazing condition! It looks like it's never been used in 40 years. Even a Coulter can look awesome if you take care of it.
I have an 8" red coulter and I have no complaints.
A 10" Coulter was my first serious telescope. The next one was a C10 Meade, similar to the other telescope in the picture. I got tired of using star catalogues, multiple finderscopes, and the bump-bump-bump of trying to track sky objects. And photography was out of the question. Still, I have fond memories of that Coulter.
Neat. I think I saw a red Coulter for sale on EBay.
I saw a 8 inch red colored for sale outta California recently.
Thanks Ed. I had the 13.1” model in the blue Zolatone finish. The mirror didn’t cool very well in that cell. I replaced the cell and primary mirror with a Discovery one.
Ooh! My Coulter story: I debated getting one for a few years. Finally I broke down and ordered one - I think it was a 13”? Anyway, after being on the waiting list for several months, they declared bankruptcy. I never got my Coulter, but at least the CC company refunded my deposit.
It's best, I hate to say, that you didn't get your scope. By the time they were declaring bankruptcy, the quality of the mirrors and overall assembly were sub-par. Murnaghan, bought them and never really brought back the bang for the buck scope that Coulter originally produced in their earlier years.
I remember seeing the ads in Astronomy. I wanted one so bad.
Very interesting. Don't think I want to own one, but interesting to hear the history of this company.
This would be a great telescope for someone who could refigure the mirror and have new coatings applied.
I like the Orion XT10 what a beast .
What a beautiful scope! By the way, I was born in 1980 lol
Hey Ed, I noticed one of the old ads in the video showed a EQ mount for the Odyssey. First time I've seen or heard about that. Do you know anything about them?
They were terrible. Practically impossible to balance. The eyepiece was either too low or too high.
I have seen a Coulter in an effective homebrew equatorial mount. It was basically a GEM on a low stanchion in a set of cast aluminum tube rings. The allowed the tube to be balanced by sliding it lengthwise, and the eyepiece could be rotated to position by rotating the tube in the rings. The counterweight was massive (this was for a 13.1" Coulter tube), and the owner was talking about moving the optics into a fiberglass or aluminum tube to lighten up the whole thing (lighter scope, lighter counterweight.)
The secondary bar is called the lawn mower blade.
OMG! That’s perfect! Thx.
Ed I hope you will also review the Svbony 102 ED doublet and 122 ED triplet someday :)
As always great information. Have you ever reviewed a 10in f5.6 deep space explorer? I have seen most of your videos. Don't think I have seen one with that scope. Tom ostahowski hand turned the mirrors form my investigations. I have one, sent it to him for mirror recoating. Did lots of rebuild. I consider it a VERY good investment. Thank you in advance
Ed, i just noticed that the first generation 10" explore scientific hybrid truss dob is still available for $599($629 for non costco members) and $649 direct from ES (and who knows, Scott might give me a deal since I put in 5 years of service with OPT).
Can you think of any reason NOT to buy this scope? I had a HUGE run of bad luck a few years ago, losing my van that was loaded with a handfull of scopes, including my xt8, a couple mounts, some eyepieces and filters, my counterweights, so I can't use my c4r on my main mount which wasnt in the van, and a bunch of music instruments/gear.
The car I got stuck with probably can't handle my beat up 10" starhopper, which really needs the primary recoated anyway, and certainly not my meade 10" LX premiere in its huge trunk case and the huge wedge which i would rather not remove from the field tripod.
It might fit my powerstar C8, which is in the original black plastic case, but if so, it would be cutting it close, and when I would go out in the van, I could bring the dob for aperture and a wider field, as well as the C8, if I had to choose one to take to dark skies, I would prefer a 10" with fresh coatings on the mirror to an old C8.
I do still have most of my dob relevant eyepieces, and most importantly, a paracorr, which i can't really benefit from if i can't truck the starhopper to any decent skies anyway.
So naturally, this scope is very appealing to my situation, unless there are significant optical or mechanical issues. Why are they offering something like this for the same price essentially as most 8" solid tube dobs are nowadays?
I do have some extra electric guitars I could try to sell to cover the cost, and I will also need an $85 shroud unless cheaper options are available .
I have some heavy eyepieces, orion 28mm megaview (uwan/pwa), 20mm WO XWA, and 14mm 4k UWA, as my heaviest and most dob relevant. With the paracorr, will that scope hold still, or need weights added to the rear?
I could live with the red dot it comes with, but will probably want to mount a telrad, and maybe even a 50mm finder if it fits wherever the red dot mounts to. I am however, mostly a telrad/rdf guy, but have no problems using optical finders as well, and like you I prefer straight through, but both of my vintage SCTs have nice right angle polar reticle finder scopes, remeber those? I have a celestron 9x50 straight through on a vixen stalk, can that be adapted to the ES? Or does it have that funky meade style finder shoe that most other ES scopes have? I suppose I could borrow the shoe from my hopper, the seller gave me such a good deal on that beater scope that he kept the metal shoe and stuck me with a plastic one. But it is a little lighter which could help. That is if the holes line up and the screws are long enough.
I know these are a lot of questions, and not with an abundance of brevity. Can you tell I am on the spectrum? :)
Anyway, seeing this, after looking at the costco website to give more info to a commenter on your xt6 video, who said the xt6 was totally blowing away his costco special omni 102, I got excited when I saw they still had the ES10s.
I am pretty sure the guy's scope was completely bottlenecked by the 90deg erect prism diagonal, which are even worse than 45deg erect diagonals, and let him know even a basic star mirror or star prism diagonal (don't knock star prisms, they aren't that bad and are usually better than cheap mirrors that come with scopes) would improve the views of the omni bringing it closer in performance to the dob, and a nice wider field companion to the xt6.
Keep that in mind the next time a commenter mentions costco. My first scope 20 years ago, 2004, was a costco nexstar 80gtl, and it also came with just a 90deg erect prism. I think all costco refractors come that way, to avoid returns from the masses who freak out when they see everything reversed when used terrestrially. They have a nasty diffraction spike, reduced contrast and light throughput, and anything wider than a 25mm plossl will vignette. The 32mm plossl was one of the first things I bought for that scope and it was immediately apparent. And when i got a modest star diagonal for it, everything else improved as well.
Anyway, I hope you can provide a little insight on this, as it might be the solution that gets me back out there, or a first step at least.
Thanks!
Last night through my 4 inch F7 FPL-51 refractor I looked at 8 to 10 magnitude galaxies, some looked brighter others less so but M101 was imposible to see even if its a magnitude 7.8 galaxy.
M101 rewards a wide field. 2° is about right. 3° is fine. It’s low surface brightness and if you can’t see darker sky around it, you can be looking right at it and not know it.
My best view ever: A-P Traveler (FL 600 mm?) and 40mm Wide Field. In a dark sky in N. Ontario, out in 2 feet of snow.
It shows well in 15x56 binocs in a pretty good sky. 4°’FOV.
Hmm but the takahashi does take much better images... 😂 sorry Ed 😅
I'm grinding a 10" blank with a target of 4.5 up at Chabot. I haven't decided on the type or style but want to use it to take pictures, I mean astro. Any suggestions? I have 3 4'' Newts.
If you're going to do photography, you'll want an equatorial mount. To get the best contrast, I recommend building a fully baffled tube. Make the baffles so that you can slide the whole assembly out of the tube (put the individual baffles on rails that slide into the tube) so that you can repaint them regularly.
Shielding the secondary against stray light will help contrast a lot, too. And, of course, make sure the tube is long enough to block stray light, and that you can cover the tail end of the tube to block stray light entering there.
For the mount, you might consider reworking an older GEM mount if you want to keep things cheap. Especially mounts with just a clock drive, though if you can find one with a declination adjustment arm as well, that's a bonus.
You can do a lot in astrophotography using relatively short exposures with this type of setup today, using a stacking program. You want a good enough alignment and drive to allow for at least 30-60 second exposures that you can then stack. At your focal length, you'll need a drive corrector for your RA drive at the very least, preferably one with PEC (periodic error correction, it makes up for worm gear flaws.)
At least, that's one approach. At your focal length, attempting to use an Alt-Az type mount is likely to give you field rotation headaches.
Another technique would be putting a Dob style mount on a Poncet equatorial platform. You'll be limited in the tracking accuracy you can get--you'd be lucky to get usable 60 second images with this setup. But if you're willing to fuss with it enough to get a good alignment, and you can get decent tracking out of it, you might be able to build up good images out of stacks of 30 second images.
@@saundby Thank you very much. Now I have some homework to do. Would a different focal length make it any easier/better?
Hello Mr ting. I recently acquired an old meade 10" starfinder. I was wondering if you had one and if you might be able to review it?
Ah, the Starfinders. Sadly, those were some of the worst telescopes Meade ever sold. The worst part is the Starfinders replaced some of the best Newtonians ever made (the 628, 826, 645, and the Research Grade series). It was an era where Meade started cheapening all of their products.
0:00 I have a 13.1 mirror from the early run, is it worth getting re coated?
Probably, yes. Put a Ronchi tester on it and see how the form looks. You can do a hairshirt Ronchi test with a Ronchi pattern printed on a piece of acetate, an LED flashlight, and someplace stable to rest the mirror and yourself at the center of curvature of the mirror (twice the focal length.) The early Coulter optics I tested all looked very good, at least, some were excellent. This was even into the period where they went to red tubes and stranded board rocker boxes in the early 80s.
I totally agree with saundby. Coulter optics in the early days were diffraction limited, and many were better than that. Perform the test to see how well figured the mirror actually is, then go from there. I had a very good 13.1 in my dob which I sold 25+ years later and never recoated-even though I considered it many times. Many custom mirror makers 12" and larger used to offer refiguring and recoating. It's pricey, but if you have the money, it's well worth it. Some of the ones I remember from back in the day were mirror crafters such as Wilkinson, Swayze, Nova, Pegasus, Galaxy and if you have tons of money Zambuto. These guys are artisans so they won't be cheap! Shop around!
I live in central FL and always need 120x to split castor. Is this normal, and why should this be? I’d figure that splitting a semi-tight double (for me, at least) would be the same anywhere.
It depends on your seeing conditions and your scope. Florida actually has a good reputation for steady seeing. That's why they held the FL Star Party down in the Keys. Around here, in good seeing and with a good apo, I can split Castor with as little as 80X.
@@edting Thank you!
I have like 30+ telescopes, but I’ve always used the Tele Vue 60 when splitting Castor. You don’t have to respond; this is simply information for others.
Welcome to observing in Central Florida. Our seeing isn't as good as along the coast, particularly in the Keys. Part of what makes it take more magnification here is that we need it to get more contrast in the image with our hazy skies. Plus, as I mentioned, we don't have very good seeing here a lot of the time because of air movement between the Gulf and Atlantic meeting over our heads and causing a lot of turbulence.
Depending on the season, we have quieter periods of the evening for viewing where the seeing will be the best. Hopefully we will have no strong El Nino weather patterns this fall, so that we'll get good clear nights and steady air for viewing the planets through the later part of the year.
I had a Coulter 17” red tube for a while. Gigantic would be charitable. Optics were horrible. Sold it within 6 months.
Blast from the past.
And here I am debating if I should get a Celestron C6 or C8 with my girlfriend, she wants me to get a C5, what a girlfriend right?
You call it the 10". But everybody knows it's 10.1".
Yes, and I've had someone tell me his 10.1" mirror actually measured 9.75". The f/4.5 ratio also seems to be a suggestion rather than a specification.
little hint, maybe you know this one already: paint a mark on the side of the mirror, and one on the rockerbox-bottom where the mirror sits. with this marking you can place the mirror in the same orientation every time, and possibly reduce the need for collimation due to differences in the thickness (and thus reflection angle) of the mirror.
A sharpie stripe on the side of the mirror on each side where it comes up over the sling bracket works great. :)