choochoo_baloo

For anyone else wondering, I heard back from Astronomik support, who said: For deep sky imaging with an apochromatic refractor the Deep-Sky RGB set is recomended. The L-RGB set gives you the best color rendering of all availiable RGB filtersets. The main benefit of this is in planetary imaging.

Same question please: how does one book to attend your talk. Do we not need a meeting ID and password? @steppenwolf

As per the title, I'm struggling to discern the difference between the 2 flavours of RGB filter sets produced by Astronomik (other than one has a luminance as well!) The technical spec's don't give an obvious contrast. Deep-Sky RGB Color Filters L-RGB Typ 2c Color Filters Thanks in advance.

Thanks Julian. I assumed the former because all of my William Optics parts seem to be. Perhaps a better question is: do you know the default thread for other big brands eg Takahashi?

Am I correct in saying that M6.0 (x 1.0 pitch) is the default thread for astro fixings - clam shell OTA rings, dovetail plates, etc?

Lars I want to thank you for such a generally useful and thorough website. It's great to have the mathematical/physics rigour for many topics. I can see me spending many cloudy evenings trawling through all of these scholarly endeavours!! 🤓

Ok thanks for the info. Actually not long after posting this, I gave mine one last attempt, and 50 thou allen key did undo both grubs. Sensible RE allen bolts - I shall do the same. What thread is the female tapping (assuming you didn't re-tap your holes obviously)?

Sorry to resurrect this thread Dave. I am just unboxing my s/h EFW2, and have the same question. Yes they are definitely intended as rotator locking grubs. However mine lacked allen keys, and I'm blowed if I can get any from my allen key set to fit it just right. What size allen key did you get to fit, although having stripped the head maybe it's not that size anyway..! How did the drilling out go by the way?

THANK YOU Marcus. I was getting very frustrated at there not being a straight forward calculation. This is even better

Can you elaborate please? Why is arctan needed if we're only concerned with the hypotenuse in the same plane? I also thought there must be increments to allow for edge effects from the filter frame etc

I bought a mono CCD a little while ago, and am researching filters to go with it. The filter wheel I bought S/H has a 2" carousel. I s there a reference for knowing which filter size (1.25", 2", 36mm etc) can serve what sensor, without vignetting? If I'm going to stick with a small sensor for a while, then there's no need to buy the bigger filters, when the smaller/cheaper behave identically. Thanks.

Lesson learnt 😕 Actually the triplet element seems to be mostly condensation - it's steadfily shrunk since been in teh house. Though some faint hazing beoynd teh shrink codesation, this could well be mould traces still. Can anyone recommed Orion Optics servicing? https://www.orionoptics.co.uk/telescopeservica.html They're obvs a top drawer optical manufacturer, so it they can't service a refractor, I don't know who can!

It's not good. The WO GTF aluminium lens cap was jammed on. Took a lot of twisting to remove. Nice big mould colony on one of the inner surfaces of the triplet objective - looks like a petri dish! I'm annoyed with the Telegizmos cover. Will be contacting FLO (suppliers) to find out about support. Gortex manage to make fabric breathable yet waterproof... I want to warn other British owners of Telegizmos 365 covers of this effect. Looking into refractor servicing.

Unsurprisingly some light mould patches have formed on my William optics scope, untouched, under a Telegizmos 365 cover since late August. I suppose the water-tightness of the cover means that the typically damp autumn/winter in Britain means mould is inevitable for long periods outside? I will now get in the habit of opening up to check more regularly now I’m back home. Main question: how should I go about cleaning it off? Thanks in advance.

Thanks for the reply. I'm happy to meet with a few others during the autumn to do our own star party thing one night or so. I will miss a semi-rural location! The Cardiff society looks pretty established?