jonathan

2 hours ago, Victor Boesen said:

I too love my 82 degree ES eyepieces but my 24mm is very heavy at almost 900g. I've also heard very good things about the Baader ND filter for planets and the moon (even as an LP filter) How's your experience with the filter on the moon and planets? I don't know if I should rather get proper color filters for studying specific features of the planets or if a multi purpose filter like the ND filter is the best solution.

The Baader 2" ND filter is mostly just for cutting down the brightness, this may enable you to see some detail that was washed out by the brightness before, definitely makes viewing bright objects easier on the eye.  Personally I would only use a 2" ND filter on the moon if I really wanted to use my PanaView 38mm or if I was going to be swapping eyepieces a lot (in a 2" - 1.25" adaptor), most of the time I think better views can be had with 1.25" and even using the front OTA cover if it has a small aperture cap one can remove, anything to reduce the amount of light arriving at the eyepiece.  I don't think refractors usually have this smaller cap, although I think maybe my ST80 did.

I've tried ND filters on Jupiter and Saturn but honestly I think opinion could go either way on their effectiveness.  In recent times I've observed Jupiter and Saturn just fine without any filters, though I read that using a red filter on Mars can help, and maybe a yellow filter on Jupiter.  Probably worth having two or three basic colours and just try them out.  I have an OIII filter which turns the Orion nebula into a fantastic ghostly aparition!  The trapezium stars come through as bright green, and it does help to show some more structure in the nebula clouds; this may also work to some degree for LP, or so I've read.

Not sure about using an ND as LP filter, I've never had one nor needed to when observing bright objects (I am under Bortle 4 skies); local LED street lights are bright and annoying, I can see one or two directly depending on where I stand in the back garden, but I don't think they generate enough LP to be concerned about (unless the target is very low to the horizon).

I'd say definitely have an ND filter at your disposal, whether it is 2" or 1.25", and in addition think about having red, yellow, or blue filters to try on planets.

I find that even if I can get a decent view with my glasses on, that I'll then often be left with smudges on my glasses from the experience.  My glasses are for distance, my close-up vision is very good, so I tend to take my glasses off at the eyepiece and it gives me a far better view as I can get right in there with the eyeball.  Can't say I've come across any eyepiece that provides a truly equal view for glasses or no glasses, I expect that to get the best for glasses wearers an eyepiece would have to be designed for it, meaning that non-glasses wearers would be at a disadvantage. 

I'm curious about the UV cure - I have read on these forums a time of about 20 minutes, but is that direct sunlight shining through glass itself or is scattered UV sufficient, e.g. eyepiece laying on it's side?

If working with lens elements or OTA glass or mirror surfaces etc I would recommend a bulb blower (with long plastic nozzle) to blast away dust and small particles etc, I could only find a medium-sized one which I bought from eBay, I wanted a much larger version (the bulb itself the size of my hand) but couldn't find where to buy one from.  I've seen advice not to use an air duster as this can spew out liquid propellant.

12 hours ago, Victor Boesen said:

At least it looked like it with an OIII filter The local vendor actually suggested a Panaview to go with the refractor but I said I already had some eyepieces. Perhaps I could ask them if I could add a 38mm Panaview at a reasonable price;) After all it's a little over 30£ more than from FLO!

It would probably suit the 100ED nice as you say yourself because of the slower focal ratio.... Thanks for recommending!

I have the PanaView as well, it's definitely a go-to eyepiece for wide field (the double cluster in Perseus looks amazing) or something like the moon.  I also really like my 14mm Explore Scientific 82 degrees eyepiece, a very nice one for clusters too.  My PanaView is a heavy beast though, it will upset the scope balance a bit, weighing at least twice or possibly three times as much as a regular eyepiece, so either adjust this or don't use it for too long at a time.  Consider a 2" ND filter if observing the moon or planets, a 2" diagonal should have a filter thread to save you some effort if you might switch eyepieces often when viewing a bright target.

When it comes to personal attachment to objects that were a part of your life at a certain time, I have quite a few of those objects still hanging around in my life!  I'm terrible when it comes to that sort of thing, always attaching memories and feelings to inanimate objects, but there is another way of looking at it, especially for something as useful or utilitarian as a good working scientific instrument, which is what a telescope is.  You are the current custodian, or owner if you like, but that telescope's journey is just beginning; whether you sell or give it away to someone else or keep it until the day you die, the hope is that it will still be in good usable condition and so it's journey will continue.  It's true, plenty of treasured items do get damaged or thrown away by people who perhaps don't understand or don't take good care of things, all you can do is care for them while they are in your posession.  If you sell a telescope be sure to do it in a place where you can be confident that the buyer is someone like yourself, who will care for the telescope, use it and get the same pleasure and joy from it as you did, then perhaps they will sell it on too, and thus the journey for that item continues.

I had a classic VW Beetle, 1972, I loved it to bits but it was terrible when it came to rust, it had a worn out engine and the heating didn't work very well, but I drove it all over the country and had a lot of fun doing so.  It eventually came to the point where I didn't have the money to fix it anymore so it just sat in the driveway crumbling away, sad and neglected.  I eventually sold it to a guy who worked in a garage so had the skills and the tools to do it justice, he was going to fix it up for his daughter to drive.  I was still very sad to see it go, but the thought that it was continuing on it's journey gave me some relief.  The car I had after that, an old Citroen AX, ended up being collected by the scrap man!  I had no qualms about that one, it wasn't a classic and it wasn't a particularly good car, no real character or personality, and I had to get my hands dirty quite a bit fixing things on it that had worn out because I didn't have the money to pay someone else to do it.

If you regret selling it and later have the desire, money and space for another one then you could always buy one again, it should look and perform just the same.  Money is just money, how you spend it on your hobbies is entirely up to you.  As others have said or implied, it is important sometimes to let go and move on, that applies to objects as well.

Oh, and if you're able to then I would suggest making an effort to get the 10" dob out to a dark site and observe Mars in the next few weeks, what better way to make use of such a capable telescope than to observe Mars at it's best, it won't look this good again until you're well into your 30s, and there are no guarantees that it will look as good even then (could be dust storms obscuring surface details).  You won't get quite as good a view (visually) through a 100mm refractor in my opinion, my 8SE SCT usually beats my 102 triplet APO when it comes to visual on planets.

OK, quick question - With a dome that has a push-to revolving top half would it be advisable / safe to open it up on a sunny day, point the dome opening at the sun and just point the scope (with the caps off) North so the sun should never track to it, in order to eliminate any fungus that has formed on surfaces?  I realise the fungus would still be around, perhaps on interior surfaces that don't catch the sunlight, but warmth from the sun shouldn't affect the scope should it?

How often would you say this should be necessary to keep the fungus factor under control?

Similarly, should an eyepiece case be left open and exposed to direct sunlight, and should the eyepieces have both caps off in order for scattered UV to contact the glass surfaces?  Will this be sufficient to kill off fungus etc (I read in a post that about 20 minutes should be sufficient)?  Is there any danger from or to eyepieces so long as they are not directly pointing at the sun?

Thanks.

Does anyone know when the best period will be to observe Mars?  October, yes, but are there any factors I should be aware of?  I saw it a couple of weeks ago looking pretty good, hoping to get an even better look!

The 80ED was the scope I looked at for getting into astrophotography, a good choice!  In the end I decided to go for a more visual route so bought Altair Astro's Wave Series 102, a very nice refractor for visual (I haven't tried photography yet but I hear it's also excellent for that).

I think on the heavier mounts (EQ5 and up) they all have an autoguider port which can be plugged into a computer for software control, and there's the handset-only approach as well of course which generally comes as standard with goto models.  You may be talking about EQ6 for an 11" scope, and definitely look at SCTs rather than newtonian reflectors as they're a lot easier to handle by comparison and at that size should be comparable in performance (from what I've read on forums). 

I don't think a dob base is going to fit your requirements, although still worth a look to cover all options as it might just take your fancy.  Goto is available, particularly for larger dob configurations, but from what I've experienced and read you're probably better off with an EQ6 mount and an 11" SCT.  In dob form you'll probably be looking at a truss design.

Take a look at the EdgeHD OTA and match to your choice of mount.  Personally I like Skywatcher mounts but that's only because that's what I have experience in, and they are white so easier to see in the dark; Celestron CGX mounts tend to be black which seems like an odd choice to me but there you go.

Beware of bundles such as the Celestron C11 SCT VX Goto, while they will work fine you may notice in the small print it states "The Advanced VX mount is strong enough to support this optical tube assembly and a couple of small accessories" which to me translates as 'the mount is almost at it's limit with this OTA sitting on it, there will be some vibration when touching the scope to focus, a couple of accessories and a heavy eyepiece will push it over the limit meaning lots of wobble / vibration at the slightest touch or gust of wind, possible motor strain and louder gear noises'. To get the best experience, especially with a heavier scope, you need to buy far more mount than you may think you need, so EQ6 is the way I would go for 11".  9.25", well... possibly EQ5, but EQ6 will withstand a gale.

Then there are the Celestron fork mounts, I have my reservations about those having owned the 8SE single arm fork mount.  I haven't tried the mount linked to but my 8SE had noisy gearing and it didn't work well when I attached additional items to the OTA, it strained with the additional weight and could not point at the zenith because of the additional length at the back of the OTA (I have a steeltrack focuser, 2" diagonal, and sometimes some large and heavy eyepieces).  If you were thinking about attaching a regular DSLR camera body then you may have the same problem with this style of mount.  This should not be a problem for EQ mounts.  Also, with any Alt-Az mount you're going to need to add a wedge if you wanted to do any kind of serious astrophotography with it (beyond basic short exposures).

My conclusion: seriously look at the EdgeHD 11" or 9.25" on an EQ6 goto mount.  You could save a few quid by looking at the C11 or C9.25 however these are more geared towards visual than photography, I have no doubt that the views through the EdgeHD series will be comparably better for visual too though.  Consider reserving a few hundred for accessories such as eyepieces and probably a 2" diagonal if the scope doesn't come with one - the Explore Scientific 14mm 82 degrees eyepiece works very well in my 8SE.

One thing I notice is that these Celestron SCTs seem to come with the 9x50 finder scope, which is a great finder scope for sure but can be tricky to find things with, luckily there are screw points already included so you can add a red dot finder shoe very easily, helps a lot to find the general area, at which point the target should be visible in the 9x50 finder (assuming they are both aligned to the scope correctly).

Hope that's of some use!

PS Also invest in dew prevention - for any SCT of this size you will need a dew shield and at least one dew heater tape around the corrector plate (front, just behind the plastic rim) of the OTA.  I have the HitechAstro 4-channel controller and AstroZap tapes around the OTA front, the finder scope (front and back), and the eyepiece.

PPS StarSense can be added to certain Celestron motorised mounts, as per the description here.

41 minutes ago, Seelive said:

Based upon the number of posts I've seen, Skywatcher control boards seem to be pretty easily damaged by possibly incorrect connections.

Yes, I've noticed that too which is why spending the money on a pre-made one is sounding more appealing.

Looks good, thanks, though it would be nice to know if there's any kind of comms standard they're following or if it's 100% proprietary.

I see FLO have a good looking one made by Lynx Astro, might be a better option as it comes with a long coiled cable as well which I wouldn't have in a DIY effort.  Hmm, might have to do some selling on eBay to generate the funds!

I have a SynTrek with my NEQ6 and that suits me fine, I presently have the opportunity to try out a SynScan handset however I do not have the appropriate cable as the SynScan uses RJ45 whereas the NEQ6 uses a DB9.  Does anyone know where I can find the appropriate pinout to make a cable, or if the cable is super cheap where I can buy one pre-made?  Don't want to just guess at the pin assignments if it could wreck stuff.  Thanks.

Have you tried without the coma corrector? 

So I didn't just imagine that the planets looked a lot better when I first got my telescope around ten years ago?

Thank you Peter, though I think now I've discovered / learned everything I need or want to know about Celestron corrector plates.

Tonight I took the 8SE outside on a beautiful clear night, set up and set to fiddling with the thumb screws ('Bob's Knobs'), learned lesson #1: Don't use Jupiter for collimation!  It just didn't seem to work.  I pointed at Vega and got a much clearer bright star to defocus and collimate to, ten minutes or so and it was looking good, focussed and there it was, all looking great and no coma or other weirdness going on. 

I moved to Jupiter, the double vision was gone, focus was achievable, I could make out three bands easily.  This is the 8SE I remember from years ago!

I slewed over to Saturn, I fancied I could see some colour variation on the planet disc - a large band - and perhaps even a variation in the rings, at least the darker outer ring was discernable - possibly the Cassini Division at a pinch.

Then I noticed something bright and orange rising in the East, a bonus planet!  I shuffled over to Mars, it's been many years since I've been able to get some decent observing on the planet.  I fancied that I could easily make out the large darker area on the planet disc, and also a definite polar ice cap.

I'd call this job 'good enough' for now, there may be another 5% collimation to get out of it but maybe not really worth the effort.  I'd rather forgotten how things look through this scope, it doesn't have the pin sharp contrast of my refractor or even the 150P reflector, but those scopes don't seem to have the same raw magnification for planets (the refractor maybe comes close, I haven't compared them side-by-side).

The dew came in and said hello to my glass surfaces, I didn't have my heater tapes on so had to call it a night.

On 05/09/2020 at 11:06, billhinge said:

Putting the shims back under the plastic and then trying to find the screw holes is a nightmare as the shims will move respective to the plastic ring. Easier to add glue to to the ring & cardboard shims to keep  them lined up before trying to replace, glued together its a simple job.

Just been through this with my 8SE, I found the card gaskets / shims easy to put back - just hold them in place with one screw then the rest is easy.

That article was dated 2011, I couldn't see mention of which firmware they were using but the latest firmware for the V3 handset (which I assume yours is, going by the firmware version) seems to be from 2018.  You may want to look through the changes to the firmware versions (or try updating) here.

The original poster of that article still seems to be active in the comments (as of January 2020) so you might want to ask your question there as well.

Thank you for your replies, good info to know.

Just wondering if this is a compatible match, as I already have the NEQ6 Pro mount and tripod but would like to know if the HEQ5 Pro SynScan mount will fit onto the tripod I already have.

Also, are the handsets interchangeable between HEQ5 Pro and NEQ6 Pro?  I have the SynTrek handset with the NEQ6 Pro, it has an RS232 style connector I think.

OK..  I've disassembled the corrector plate and secondary as far as I think I should, done some science / maths (or drawing, but a ruler and poor mental arithmatic was involved), and come up with the following photos.

I believe I have the secondary carrier centered, according to my measurements and doodles, it's just a matter of working out what these strange markings mean and how to put the pieces back together in the OTA.  Astonishingly there seems to be about 1.5 or 2mm wiggle room for the secondary carrier in the glass!  I wonder if this is on purpose to allow for metal expansion / contraction.  I didn't like to star prying at the carrier, there is no obvious way to remove it from the glass other than leverage with a screwdriver (the outside part of the carrier is metal, the inner cone where the secondary sits appears to be plastic, they are probably clipped together).

I used some precision measuring and a compass to draw myself a template to work from, then cut out the central obstruction hole so that I could fit it over the corrector plate and carefully draw around the edge of the whole plate.  This drawing marks the positions of the screw holes in the holding bracket and also the positions of each trangle that was scratched on the outside edge of the corrector plate glass.

The various markings didn't make much sense to my eyes, sometimes there were two triangles and what looked like a number (8, 0, 3... that's what they looked like to me), except for this one shown below which had no number.

And just in case anyone was curious as to what the secondary looks like in an SCT...   (the three collimation screws are underneath)

Anyone any ideas on how to proceed?  My only plan is to pick one of these symbol groups and align it to what I would guess at being the 'top' of the OTA, the point opposite the dovetail bar mounting.  There are no markings that I can see in the OTA though there is a screw hole so I'll just use that as a starting point.  As for orientation of the secondary, I can only go by photographs of other 8SE scopes, I believe it should be two screws towards the top with the 'FAST' logo upright. 

... wish me luck!

Update: I noticed that the secondary only fits in the carrier one way, there's a grub screw on one side of the secondary holder and a cutout slot in the carrier for it, that removes that potential problem from the equation at least.  Need to wait for the next clear night to test it (I don't have enough room indoors for an artificial star, couldn't place one far enough away).

The 'FAST' logo was not upright after I placed the secondary in the carrier, come to think of it I don't remember it being upright before anyway, probably changes from scope to scope.

The other night mine looked like that scene from 2010 when the monoliths all piled into Jupiter near the end, a black spot right near the edge!  It needs a bit of work...

1 hour ago, turboscrew said:

Also, I'm not that convinced that alt-az is so much easier. You don't really have to polar align it that well, if you are only doing visual. With rough alignment eq mount probably works a bit netter than alt-az.

I agree on the polar alignment question - when it has been set up and approximately aligned once then it's quite quick and easy to just put the mount in the same approximate place and orientation in future sessions without having to use a polar scope for accurate alignment.  I know where the pole star is in relation to my tree line so I just point the N leg of the tripod in that direction, gives me 80-90% tracking accuracy almost every time which is fine for visual.

Bright light sources do strange things through multi-element lenses.  Are you certain the second disc wasn't a spec of dust on the lens?

Yes, I've heard of Bob's Knobs, I think it must be time for those.  I had a thought that perhaps the screws have become stiff over time (I haven't adjusted them for many years), perhaps they've corroded with dew or something like that.

I feel that I should remove the secondary module from the corrector plate purely so that I can see what's going on in there.  There is a central disc on the outside of the secondary, does that just flip off to reveal a screw?

I do recall vaguely unscrewing the inside half of the secondary but I don't rememeber what it looked like behind the mirror.  Time for another adventure in telescope maintenance!

I see on FLO there are many different Bob's Knobs - does anyone know which would be appropriate for my Celestron 8SE?  It has an orange tube but I bought it new only about ten years ago.  I'm thinking these will be the ones, I need to remove a screw to confirm that it is metric.

Recently I took the corrector plate off my Celestron 8SE and cleaned it (it was quite badly fogged with dust or something on the inside), this part went well, however it seems that the central part didn't go back quite as it was so now it's rather badly out of collimation (the out of focus bright star shows a black dot far off to one side).

I had the scope out tonight attempting to collimate it by twiddling the three screws on the central part however they were extremely stiff, to the point where the heads started to strip, also when I was attempting to turn the screws I noticed the whole central part moving.  This worries me greatly - how can I possibly collimate this thing by adjusting the screws if they won't budge, but somehow the whole central part moves about?

Anyone who knows what's going on here, please help!  I was not able to achieve focus with the scope tonight, a very clear night by the looks of it. 

I will need to remove the corrector plate and examine the central part, I'm not sure why the screws are so very tight nor how it is able to shift up/down/left/right over the correctly plate.