John

Hello and welcome to the forum. This link should be the instruction manual that covers your scope: Celestron1510UsersManual393336.199887065.pdf Feel free to ask questions if things are still unclear.

There is a section in this piece by Howie Glatter titled "BARLOWED LASER PRIMARY ADJUSTMENT" which goes into the optical principles: http://www.collimator.com/collimation

Hello and welcome to the forum For balcony observing a short tubed scope would be desirable I would think. Something like a maksutov-cassegrain perhaps ? These show no false colour and "refractor like" views in a compact package. For example: https://www.firstlightoptics.com/maksutov/skywatcher-skymax-127-synscan-az-goto.html

I agree. Even though I don't do a lot of solar observing, even I found a noticeable step up when I moved from a Baader film filter (Kendrick) to the Lunt Herschel Wedge.

From what I've read, the Vixen HR's are very close to the best planetary eyepieces that you can get and in the same league as the Zeiss ZAO's, TMB Supermonocentric's, Pentax XO's. The Takahashi TOE's and Tele Vue Delite's are excellent but just a step down in terms of outright planetary performance. The Vixen SLV's (which I have used and reported on) a small step down again. Still very competent though. The very best mentioned above are out of production and practically impossible to acquire now at any price. The Vixen HR could well be in a similar situation soon so picking one or two up while they can be got and at a reasonable cost makes sense if you are looking for that type of eyepiece.

These eyepieces have been branded many different ways since I first saw the as Astro Tech Paradigm's 11 years ago: https://www.cloudynights.com/articles/cat/cn-reports/eyepiece-reports/first-look-astro-tech-paradigm-eyepieces-r1845 Barsta, who make them, had their own brand name, originally the BST Explorer's and then changed to Starguider's when, I believe, they were told that another manufacturer had claimed the Explorer name was theirs. It maybe that Astro Essentials is a branding that FLO have specified ? If you order enough you can have the branding you like printed on them. At least Barsta didn't use the branding "Barsta RD's"

Nice reports folks Very large storm clouds building over here currently - I'm not going to risk putting a scope out

A few things bother me about the photos of that scope. The diagonal is missing it's eyepiece tube which seems to be attached to an eyepiece in another photo. The finder scope bracket is on backwards. I wonder if the seller knows much about the scope he / she is selling ? If the GOTO is not working properly, they might not be aware of it ?

It's been more like an open cast mine with me

I have the Astronomik H-Beta in the 1.25" size. Apart from the Horsehead Nebula I have not really used it on much else I'm glad that I have it because seeing the HH was a long held objective of mine. My UHC and O-III filters see a lot, lot more use. Perhaps we need a rental / loan arrangement for these seldom used tools ?

I would get a mirror diagonal for an SCT. Good quality prism diagonals work well in slow refractors. not so sure if the bring the same benefits to an SCT ? By all means buy the Celestron if you like it's looks but be aware that you are probably paying £70 for those looks. The underlying diagonal is the same as the Skywatcher one and almost certainly made by Synta who make Skywatcher stuff and own the Celestron brand now.

They are excellent scopes. Large and heavy though. You will probably want more eyepieces plus some collimation tools, a Telrad and a RACI optical finder. While the Moonlite focusers are very good but why not try the stock one first ? - they are not that bad at all. I would probably invest in the list above before rushing to upgrade the focuser.

I use this approach when I'm using the barlowled laser collimation method. It works well for me http://www.smartavtweaks.com/RVBL.html Mind you, the collimation adjustments that my F/5.3 12 inch dobsonian requires are generally very small so usually I just use a cheshire eyepiece and then a quick star test to check.

I'm doing something similar here. There is quite an electrical show going on towards the north currently. Either Pink Floyd have reformed and are playing a monster gig or there are some thunderstorms over Chepstow and the Wye Valley. The latter is more likely I suppose

I have recently bought a Skywatcher 1.25 inch diagonal to use in a small mak-cassegrain. This one: https://www.firstlightoptics.com/diagonals/SWdiagonal-20967.html Although it does not have the twist lock eyepiece clamp that the Celestron does, it is otherwise identical and my guess is made by the same manufacturer. I bought mine 2nd hand for somewhat less than the new price and a lot, lot less than the Celestron item is listed at. The diagonal works very nicely but I don't think I would pay £100 plus for one, even with the twist lock clamp.

I don't know quite how this feeds into this interesting thread but one of the times when I find using very high magnifications useful is when I'm trying to see faint point sources such as the dimmer planetary moons. When I've observed Neptune's moon Triton and Titania and Oberon at Uranus I've found that really high magnifications (400x plus) have been helpful in teasing these faint points of light out of the background sky and the glare of their parent planets. Sometime over the next couple of months I'm hoping to use my 12 inch dobsonian in this way on Mars to try and spot Phobos and Deimos.

You have to be a little careful there. Their pricing is, I would say, somewhat higher than a personal sale is likely to realise.

Done. I had similar issues to @davew on some of the terminology used so I used a best guess there.

Takahashi FC100-DL tonight. Lowest power that I had a confident split of both pairs was at the 13mm setting of the zoom so 69x.

I currently have the Celestron branded 90mm F/11 and it's proving to be a nice performer as well

I find that using a higher magnification with a wider field of view helps me to find faint objects a little easier because the background sky is darkened enabling the deep sky objects to be just that little bit easier to spot. I observe mostly from an area with some light pollution. I have 40mm, 31mm and 21mm eyepieces which all show around the same amount of sky. The 21mm (which happens to be an Ethos) is that one that gets used the most for deep sky sessions. The 20mm Myriad or APM 100 degree eyepieces are a lot less expensive than the Ethos 21. The scope that I would be using mostly for this is a 12 inch F/5.3 dobsonian.

The 7mm will see more use although my my 12 inch F/5.3 I find 6mm the "goldilocks" high power much of the time. I do use the 5mm XW quite often to tease out the finer lunar details though. I hesitate to say "get both" though because it's so easy to spend other peoples money !

I'm going to be experimenting with my Giro Ercole this evening. Fortunately I have quite a lot of scopes and counterweights to play with ! Forums are really helpful with these sorts of issues - a number of folks kicking ideas around can be really productive

Good seeing here just now. No filter (Tele Vue discontinued them after a couple of seasons) but the Martian disk looks pretty much like this with the Tak 100mm: