Pixies

Hi, I've recently bought a new finder to replace the plasticky little one that came with the Bresser 8" dob. The recommended shoe is the Baader universal, which I have too, The Baader has 3 screw holes. The shoe I have removed have 4 in a square layout. I can either use two width-ways, or just a single one, and use the middle hole in the Baader. I prefer the latter, because it means I can shift the shoe across slightly, and leave room for the new Telrad. The Telrad also then covers 2 of the remaining open holes. See pictures below. Otherwise, the Telrad won't fit in the gap left between the Baader shoe and the focuser. So I have 2 options: stick with what you see in the picture, or use 2 screws to hold the new shoe and replace the Telrad with a Rigel Quikfinder. Either way, I need to fill in the remaining open 6mm hole(s). Also, the screws and nuts that were fixing the old shoe are too narrow/long for the Baader - I don't fancy them sticking over 12mm into the tube, especially as the screws are shiny silver. The nuts are black though, but M4, whereas the Baader really needs M5. So eventually got to the point of the post. Advice, please: 1) I can get the correct M5 bolts in various configurations, but can't find any black M5 nuts available in small volumes. Any anyone suggest a suitable source for black M5 nuts? Otherwise I'll be painting them in place - and I don't fancy that. 2) Has anyone had any luck using grommets or blanking plugs to close these holes? Or should I be looking at very short bolts? Thanks.

Hi AA&D, Unless you are going to have issues carrying the larger scope, I'd go for the 200. Otherwise you will always be thinking "I'd have seen more/better/clearer" when looking at something through the 150.

Did you report it to eBay?

There's another thread about this scope. You could ask to see if anyone else is seeing this issue?

Is that little dovetail moulded into the main part, or bolted on?

Can you get a pic of the mounting plate / shoe on the scope?

Looking good! Wish my secondary was that spot-on to start with!

The M13 and M57 were the first things I observed when I got my new scope. The Ring nebula is great - it looks so incongruous when seen in a scope (IMHO).

If it's cloudy, now's the time to learn. And if the locking screws are loose, then it will probably need a quick tune up. Plenty of expertise on here. I've found the following 2 resources were excellent: https://garyseronik.com/a-beginners-guide-to-collimation/ http://www.astro-baby.com/astrobaby/help/collimation-guide-newtonian-reflector/ And I hope it goes without saying.. Keep fingers away from the secondary mirror surface. I always wondered with these open heritage designs, how easy it would be for someone to mistakenly get a fingerprint on it?

Could it be an exit pupil thing? I guess if your focal ratios have all been similar, the same EP focal length would mean a similar exit pupil. This would affect the sky brightness and, if the exit pupil, wasn't too large, would help with astigmatism?

I see a lot of references to bikes. Is there a correlation between astronomy and bikes? (Visual vs Astrophotography) VS (road vs MTB)? Anyway - back to Dannomiss' last question... You mean the 3 primary mirror collimation locking screws? There appears to be 2 schools of thought. I guess most would say you need to tighten them up once you have collimated the primary with the 3 adjusting screws. However, they can throw out the collimation slightly. The other school says don't bother with them if you are happy collimating the primary at each use. I'm in the first camp (although a newbie). You can see how they alter the collimation if you are a less than very gentle. I treat them as the final stage of collimation - like a fine-tune. However, don't tighten them too much, as they will just take over collimation duties from the main adjusters.

OK - you've persuaded me to see how it goes removing it!

Yep - I've got to find room for that as well!

It's: https://www.altairastro.com/altair-10x60mm-raci-finder-scope-90-deg-erect-image-prism-variable-illuminator-eyepiece-2504-p.asp but from Astro Buy & Sell

Except with my head! Seriously, thanks everyone. I'll just have to try to avoid being my usual clumsy self!

Hi, My new finderscope has arrived and it is considerably larger than the little plastic 6x30 that came with the Bresser dob. Up to now, I've been lifting the scope in and out the back door with finder attached, and keeping it in a quiet corner of a room when not in use - with finder attached. However, I'm now nervous I'm going to whack the finder {on the door | with my head | with a small child} when moving it outside. I'm loath to take it off for storage and realign it each time, though. Does anyone have a cunning solution they use to add some kind of protection to the finder? I'm thinking of trying to fashion something out of the various bits of plastic packing material I have knocking around the house just now.

I have seen that spike on my 8" dob after 30 minutes, but gone at 60.

I've seen that extra diagonal spike when the tube hasn't cooled completely.

How do you find lining it up when you first start? With a straight-through, I keep both eyes open and usually find the starting target that way. I assume with a RACI, you will need to sight the whole tube in the right direction first? I'm just about to replace a rubbish little straight finder with a big illuminated RACI, and have bought a Telrad to accompany it. It's an 8" dob.

Baader Click-Lock on sale in the For Sale section just now. Spooky!

New finder to replace the cheap plasticky one that comes with the Bresser Dob. With this and the new Telrad, nothing will escape my gaze..... mwahahahah! Just need to get them both fitted. What was the Synta/Vixen finder shoe that a few folks here recommended to replace the Bresser shoe?

New finder!

Here is the sticky thread with various SkySafari observing lists: There are many directly available within the app, under the Observing Lists 'online repository'.

I'd say go with Plus. Pro gives you "Astronomy League Supernova and Quasar Database" plus purchase options fro some big databases. The comparison chart is here: https://www.skysafariastronomy.com/ the free one doesn't give you teh POV stuff. Neither does it have the observing lists, which are REALLY useful!

Had some coffee now? 😉