spaceslug

23 hours ago, EdG said:

I feel your pain, trying to explain to someone (especially a child) that they shouldn't grab hold of the telescope to look is pretty tricky.

Thankfully my daughter is a non-grabby nearly 18 year old 😃

..... or to my wife whenever she looks through the telescope! Then she complains that everything is wobbly. 🤨😂

On 25/09/2021 at 14:56, Andy ES said:

On 25/09/2021 at 09:31, Bigwings said:

Who considers the cost of repair when choosing a scope? I do now

Very good point. I’ve got a slight feeling of foreboding about how much it will cost to repair my CPC Goto when it fails, as it surely will and if it will still be supported them. 😬

I agree, it is a worry. As mounts are becoming more technically-advanced with wifi, GPS and phone/app connectivity etc., ongoing support and repair costs will probably be a big issue in the not-too-distant future. I bet the optical elements will long-outlast the electronics.  

On 27/09/2021 at 16:26, Tiny Clanger said:

The cheaper basic skywatcher 2x barlow I own does the same,  it seems to e a standard feature on many barlows.

The Celestron 2x barlow I have also has this feature, but I never thought to use the removable bit with another eyepiece. Will have to give that a try thanks.

On 27/09/2021 at 19:49, Second Time Around said:

I'd also add that using a lower power eyepiece plus a Barlow is often more comfortable than a higher power without a Barlow.  I find that the more comfortable I am, the more I can see and the longer I can observe before getting tired.

This is because some high power eyepieces (including Plossls) have poor eye relief meaning that you have to get very close to the eyepiece, and even then you may not see the full field of view, especially if you're wearing glasses.  The lower the focal length of such eyepieces, the smaller the eye relief.  However, if using a Barlow the eye relief will be that of the longer focal length eyepiece you're using it with.  In fact, the eye relief is usually slightly longer.

That's worth knowing thanks, will be giving that a try too.

On 14/09/2021 at 14:04, Tiny Clanger said:

I thought you just need to buy one of these:

https://www.firstlightoptics.com/misc/zarkov-cloud-gun.html

Brilliant, but we really need a much larger calibre version of it!

19 minutes ago, Spile said:

So you don’t think he was right?

I don't recall saying anyone was wrong. I canvassed opinion, weighed up the responses and came to a decision based on the comments made. I *will* clean it, it's just a question of when.

If by chance a seagull does poo on it, rest assured I'll do it sooner. 

5 hours ago, Stu1smartcookie said:

This is right up my street ! 

I bought a 12" dob from another SGL member and the only thing "wrong" was that the primary was really dusty . I actually had to get the primary recoated in the end because it was quite badly stained. BUT... when my mirror was caked in dust etc i still got acceptable views through it  maybe just losing a bit of contrast . I took the mirror out and cleaned it which made a difference. The views became sharp again , despite the staining 

The point i am trying to make is that the primary on my scope was in a very poor state but still produced fine viewing . If you are getting great views then why clean it although i bet you are like me ,can't stand seeing dust on the primary . But  cleaning a mirror isn't the perilous procedure that we are led to believe . 

 

I am a bit OCD when it comes to dust on optics! I use camel hair brushes on my camera lenses and other optics to keep them dust free but this is not an option for a newt!

5 hours ago, Laurieast said:

Rule No. 2 for Newtonion Owners:

Always have the open tube horizontal when doing anything. Exception being collimation of primary.

Remember gravity and falling objects.

Good advice, though I did make sure the wrist straps were in use when using the torch. 😁

As for cleaning, I am a bit nervous about this despite the reassuring words above. I'll research this further but for now, as it seems perfectly usable I think I'll put it through its paces as is and monitor it with a view to cleaning it in the spring or sooner it it deteriorates further.

Thanks all.

Mike

Sorry, late to this thread but I just had to share this given the topic.

We have occasional star meets in our village and one of our number is within walking distance of our preferred observing location. 

This is his transport solution for his 8" Dob........

😃😃

Looking for some advice again please folks. 

I bought a second hand Skywatcher Skyliner 250 over the summer and got first light with it a few days ago. Very pleased with it, best views of Jupiter and Saturn I have ever had with a telescope. With a 10mm eyepiece, banding was clearly visible in Jupiter's atmosphere and I could clearly see Saturn's shadow on the rings. At one point, I thought the optics were fogging up but this turned out to be due to Jupiter just grazing the top of some trees in the next garden. While investigating the cause however, I shone a torch down the tube to check the primary and was horrified to see how dirty it looked.  I checked it again in daylight the next day just to make sure it wasn't dew. If I look at it in natural daylight (as I did when inspecting it prior to purchase) it seems fine, but if I shine the torch at it the dirt is there. I took a couple of pics to illustrate this, see below:

I've read up on how to go about cleaning the mirror so I think I'm up to speed on that, but I have seen a lot of sources saying not to clean if it isn't necessary due to the potential risks associated with the process. Given the performance doesn't seem to be impaired, should I leave well alone or am I likely to see a big improvement if I do clean the mirror?

Thanks

Mike

Very nostalgic topic.

As a kid, I had a network of olds in the neighbourhood I used to visit once a week to collect tea cards. I still have a number of my original albums, including the iconic Race into Space. In my adult years, I've continued to pick these up from flea markets and collector's fairs. A few years ago, I found quite an unusual one I'd not seen before called The Space Age, similar to Race into Space but with astronomy cards too. Here's a few pics:

Thanks again for all the replies.

Despite it being a bit of a faff to adjust, I think I'll try the variable polarising filter to start with and see how I get on.

Mike

Thank you everyone for the useful replies and info, much appreciated.

I will look into the variable polarising filter as I quite like that idea and it looks to be a very cost-effective option. 

I had toyed with the idea of a binoviewer as well so this may be the excuse to invest in one!

Thanks again.

Mike

12 hours ago, Kon said:

You could also get a cheap Variable Polarising Moon Filter; I do not use it since I am happy to look even at full moon directly with my 8" Dob. On the other hand, my wife prefers looking at the full moon with the filter on and the fact you can filter how much light comes through is a nice option.

https://www.firstlightoptics.com/moon-neutral-density-filters/astro-essentials-variable-polarising-moon-filter.html

 

Interesting. I like the idea of a variable polarising filter, I've used one on my DSLR camera previously for standard terrestrial shots.  I may be about to challenge the "no daft question" comment though; if this filter fits on the inside base of a 1.25" eyepiece like other moon filters, how do you control the variability when it is attached to the telescope?

Thanks in adv.

Greetings 

I've been a lurker for quite some time and have found this to be a fascinating and useful website. I freely admit that the recent (and entirely understandable) policy change on the classified section has encouraged me out into the light (dark?) and to ask one or two probably daft questions. 

Having found some of the technology associated with astronomy irritating at times, I've recently acquired a Skyliner 250 manual dob to experiment with going back to the basics of the hobby. Very impressed with the optics for the money, but last night I was looking at the moon and it was the brightest I'd ever seen it in a telescope view; far too bright in fact. I put the end cover on and removed the cap on the small aperture to reduce the amount of light coming in, which seemed to preserve the detail although gave the rising moon a bit of a yellow tinge. I was wondering if this was the best way to reduce the brightness, or whether a decent moon filter would do a better job?

Thanks in advance

Mike