Pixies

I'm afraid I've made a bit of a boo-boo!

It looks like I've been a bit cack-handed with the screwdriver when trying to adjust the secondary mirror of my new Bresser 8" dob. The mirror holder is made of cheese (apparently), and I've managed to dig the screws into it! (see pic below)

It has always 'turned' as I tightened down the screws, and now I've really dug into it. I didn't think I was using a lot of force, but it's hard to tell using a screwdriver. I noticed some tiny swarf lying on the inside of the tube (it was horizontal) stopped and panicked! Eventually saw what was happening by taking some photos. Anyway - I have learnt my lesson the hard way. Now I have to fix it.

I intend to remove the secondary, add a steel washer (countersinking for the new 3 machine screws with rounded ends). I'll also make sure the face of the holder is smooth and add a plastic (milk carton) washer to the surface between metal washer and secondary holder.

However, I'm paranoid that I don't do any (further) damage - esp to the mirror itself. Can you recommend a safe way to protect the mirror? Is it worthwhile wrapping it in a freezer bag, say, or a clean lint-free cloth with elastic bands, etc. Any suggestions on this or other considerations very welcome.

M4, M5 - going to have to take one out and double-check. Thanks John

Hi,

My recently purchased 8" Dob has 3 small philips-type screws to adjust the secondary mirror. I am aware that some similar models (like the 10") have knurled knobs instead. In fact, the diagram on the cover of the manual for the 8" Dobsonian has them too. (See below)

FLO have confirmed that they cannot source these as spares. I have spoken to Bresser who say they do not supply them either. Bresser UK (Telescope House) confirmed this but say they are M4 screws.

Before I take one out to measure and try and find an alternative, has anyone here done this and can they suggest a suitable alternative? 

I keep my binoculars in a cupboard (near the back door) where we used to have a box of Indian Dalit candles. The candles were only lit once (smelt nice in shop, but not alight). They were thrown out years ago, but the binoculars still smell of them! 

Is it just me (or my new scope), but when I take off the dust cap, there is a very distinctive solvent-like smell?

It's a Bresser 8" dob. It could be paint, glue, lubricant, or a mixture. Anyway - I quite like it. I guess it will wear off pretty soon.

I Enjoy Astro Biscuit's videos. this one is particularly funny when his wife overhears him say how much his telescope really cost!

4 hours ago, John said:

I use the Celestron Illuminated RACI finder on my 12 inch dobsonian.

I don't use the mount that it comes with though. I took the finder out and fitted it into a Skywatcher 9x50 RACI mount.

 

John,

Do you still have the original Celestron mount that it came in?

I also had a look at the Explorer Scientific RACI, but it's a polar scope and has an engraved pole star finder diagram as the reticule, which is a bit of a bummer! It would fit the current bracket though. It's surprising that none of the Bresser 'group' has a RACI finder to fit their own bracket. 

Blimey guys, thanks very much!

I've got a lot of things to decide on now - I'll look at total costs, delivery times, etc.

One thing though. The finder bracket on my Bresser 8" looks a little different to most others. It's the full sized one, rather than the one with only 2 bolts (see below). Can anyone confirm that the Baader bracket will fit this?

Hi,

Does anyone here have a Celestron Illuminated RACI Finder Scope? I'm looking for a RACI finder for my Bresser 8" Dob (illuminated if possible), but can't see what type of fitting this has, and work out whether I can find a way to fit it to the Bresser.

Cheers

12 hours ago, Andy0306 said:

If all goes to plan, I'll be picking up a 150p tomorrow. Once I get it home, I'll start the panicking 😅

Don't panic about collimation. There's so much apparently conflicting advice out there, it seems a bit daunting. But as long as you have a little mechanical ability it's pretty straightforward, once you see it in the flesh and you can get your head around what it is you are trying to do.

Don't rush down the path of buying all the expensive collimation accessories at first. I've managed to get it done with just a basic £9 collimation cap. After you have tried a few times, you will know better what extras you will need. Lot's of good advice available on SGL. And ask the owner what they use - and will they be supplying it with the scope?

Do you know what eyepieces it comes with?

3 hours ago, scarp15 said:

An 8" scope is a great tool to take out to darker skies, it will be easy to manage and will deliver impressive observations that are improbable from light polluted zones. Going to dark sky locations can be an infrequent pursuit yet it can become habitually addictive. One final thought, if the nature reserve parks (with large carparks) are anywhere near urban areas they might be best avoided as anyone else showing up late on is maybe unlikely (but not improbable) to be either an astronomer or photographer. 

Hmm - had crossed my mind. Sitting there with a red lamp, too! 😳

Thinking about later in the year when we MIGHT be able to get out and about to dark skies. I'm in Edinburgh, so the lockdown is a little stricter, now; but when the nights are darker, in Autumn, hopefully we'll be able to travel for skywatching.

Anyway, I'm in a Bortle-6 area with some local light pollution. However, I can get to Bortle-3 in 40 minutes. I'ts the Lammermuir hills which I've become slightly more familiar with during the last few years with a cycle club. However, I've never driven out there overnight. I know what the Borders night skies can be like, regularly stopping when passing Kielder to have a look, but this was before I had a scope.

So, once things have returned to normality, I'd quite fancy heading over to the Lammermuirs in the car with the scope. However, I'm a complete noob and I'm wondering how this usually works for you when trying to observe in public areas? The roads I'm thinking of are very rural, with hardly any car parking and side roads lead mainly to farms. 

Is anyone familar with the area or somewhere similar? Is it do-oable with a biggish scope (8" dob) and what is your advice for public observing? Or should I be looking for a less-farming area with perhaps more suitable locations like nature reserve car-parks?

Cheers
Pix

Morning!

OK - so as they say, "a picture paints a thousand words":

11 minutes ago, johninderby said:

Wish FLO would stock a Concenter. 🙏🏼

If they did, I'd consider it. 

Is that with a star test when out in the dark?

49 minutes ago, Dr Strange said:

A Cheshire collimating eyepiece will really help with collimation. And collimation needs to be done each time you move the scope. It is very easy to do once you get the hang of it.  

Sorry to hijack. But as a newbie, I'm unsure of how frequently collimation is required (and what type). Most of us will be moving our scopes each viewing session - and in my case I have to move it depending on my target, since the back garden is surrounded by various obstructions. Are you saying we should be thinking about re-collimating each time? And are you talking about just collimating the primary, as the secondary (as I understand it) needs collimation much less frequently?

Thanks

OK - update of tonight session - Sunday 10 May. Don't worry, I'm not going to do this every night! This is just a follow-up.

As the viewing is pretty limited just now, especially from my back garden, I started by hunting the same easterly targets as last time. Mainly in Hercules and Lyra. 

M13 (Hercules Cluster), M57 (Ring Nebula) and Double-Double were successful again. I managed to split both of the latter this time, although it felt like I was climbing inside the 6mm Plossl. I'm not a fan of it - I bought it from a seller on here (the 18mm Starguider I got from the same seller is much nicer). I need to think about a different higher-powered EP.

However, I had more success in finding M92 this time. Smaller than M13, when using the 6mm EP it's framed better and its slightly sparser nature makes the brightest stars stand out more. 

After Whistlin Bob's suggestion, I tried M81/M82. I'm getting the hang of the 6x30 finderscope and managed to land on M82 first go. I was down on my knees at the time - so thinking a RACI finderscope will be an imminent purchase. In the 18mm EP I could get both in the one view, but I think they looked better as a pair in the 25mm. Faint - but more obvious than the Whirlpool; M82 is more 'concentrated' than M81, I think. Pleased with myself again, I saw in Sky Safari that NGC 3077 was close by and thought I'd have a shot at it. It was small and faint, but I definitely found it - not that I would have noticed it unless I knew it was there. 12 million light years, blimey!

Looking to replace the 6x30 plastic straight finder that comes withe the Bresser 8" dob with a 10x50 RACI-type finder.

I'm new to this and have been finding it hard to see the cross-hairs in the current 6x30. Is it much easier to have an illuminated reticle when using the finder? Or are there drawbacks?  Obviously the brightness needs to be adjustable and low enough not to affect your dark-adaption.

Thanks

The manual says it's the friction screw, to adjust the resistance of the adjusters. The fixing screws, that hold the tube in place, are smaller and on top of the body.

3 minutes ago, Stardaze said:

Which was how mine was 😂

Got an email from Bresser yesterday confirming the replacement bracket has been despatched. The SW 9x50 RACI isn’t due till the end of the month though 😔

 

Does that mean I have 2 faulty brackets!

34 minutes ago, Whistlin Bob said:

Excellent report! Your enthusiasm comes across in spades and reminds me why I still love visual astronomy so thanks for sharing.

Well done on snagging m51- that took me a long time to get in my 8 inch. I'm certain that if you were able to see that then at least two thirds of the Leo triplet will be quite easily available to you when conditions are more favourable- you still may just get a view this year when there's less moonlight about. 

If you got m51 then the m81/2 pairing should be available to you- is quite well placed at the moment 👍

30 minutes ago, Stu said:

Great stuff, a really successful first session, far better than most of us managed on our first nights in sure!

If you managed M51 then you should be able to get quite a few other targets even given the brighter nights, it’s not an easy one.

Thanks guys.

M51 was at 70deg alt, so made for much better viewing.

M81/82 - right, that's Sunday night's target!

Thanks.

Regarding the plastic tabs, the holes drilled into the alt bearings for the fixing bolts only allow said bolts to pass through as above. The holes are larger on one side than the other, so the wider shank part of the bolt has to be on the outside, along with the tabs. I couldn't set it up as you suggest, as the bolts won't fit. BTW, these are the new alt bearings with the white surface - perhaps the design has changed?

Thanks for the advice about the tube rings. I'll get that fixed.

Morning all.

I'm still buzzing from the last 3 hours fun. I've been observing with binoculars for years, but tonight was the first night with my new 8" dob (Bresser), and it went so much better than I expected. Bearing in mind that in Edinburgh now, astronomical twilight is the best I can get. It's Bortle-6 here too, with some nearby streetlights and railway yards to the south, with lots of spotlights.

Anyway. I started with Leo. Always fancied finding the triple - but no luck. So I had a shot at M13 in Hercules. I have seen this in bins plenty of times, so knew exactly where to find it. And boom! Using an 18mm EP (x67) is was a lovely blob, I could make out individual stars, even against the light background, averted viewing helped. I tried my 6mm plossl (x200) and I was surprised how nice it looked. Really 'glittering' even though it was rushing past the view so quickly.

Then I tried M92, but couldn't find it.  It was still hard to find much in the finderscope, let alone do any star hopping - not for my noob skillz.

Next I had a look at double double. Easy enough to find, but with the 6mm, I could only split one of the pairs. Not sure if it was the viewing, my eyes, the plossl, or just lack of experience. It's not my best eyepiece, though.

Anyway - nearby was M57 the Ring Nebula, so I thought I'd have a shot, not really knowing what to expect. Wow! It's a nebula, it looks like a ring! It was so clear, both in 18mm and 6mm eyepieces. This was the highlight of the evening for me. I really didn't think it would be so obvious in these conditions.

OK - I was cooking on gas now, and at 1am the sky was as dark as it was going to get. I thought I'd try the Leo Triple again. I got more comfortable and took my time star-hopping using Sky Safari. Still no luck though, trying the 25mm and 18mm EPs. I am very confident I was looking at the correct locations, everything matching-up with Sky Safari, but nope, nothing. It was getting low on the horizon and the LP from the rail yards was obvious.

So for a final shot, I thought I'd try M51, the Whirlpool galaxy. Straight up, almost; star-hopping was a little tricky but I took my time and after a few attempts I found it! Just a couple of pale 'clouds' with averted vision, but definitely the Real McCoy!

Can't wait until we get some dark skies again. The Leo Triple will have to wait until next spring, I guess.