John

I have managed to split Antares once - with the aforementioned 130mm triplet refractor. Most of the time it has not split for me - it's too low for comfort here.

Great report Mark !

Here is my sketch of Zeta Hercules made with my ED120 refractor. It is still a tough split even with my 130mm LZOS triplet refractor:

I find UHC and O-II filters very useful for observing nebulae, especially planetary nebulae and super nova remnants. They don't provide any benefits for viewing galaxies and star clusters - the opposite really, the diminish the view of those.

I tend to use them at low to medium magnifications but sometimes at high magnifications on smaller targets such as the little planetary nebulae.

Smaller aperture scopes (less than 100mm) probably get better results with a UHC filter because those have a wider light band pass width than the O-III filters.

Astro photographers find these filters very useful as well but there are filters that are optimised for imaging and those optimised for observing. The latter will work for the former purpose OK but the former type are limited in their usefulness for observing.

Dark skies will help get the best from them, as with all deep sky observing.

You are correct that these filters do only permit certain wavelengths of light to pass through. Pick a target that emits strongly in those wavelengths and you get the results. Stars do get dimmed and can take on a different tint but it's the nebulosity that you are using the filter to see.

Great stuff Mark

For me, I've found that the key to SN2020jfo is the right angle it forms with the galactic core and the star just to the S of the galaxy. I've marked what I look for - the green lines are the angle that I look for which rules out the other faint star that can be seen at a more acute angle (red line). Hope that helps a bit. I think this one is still brightening. Below is the newtonian view:

I agree with Mike. The quality of the lens figure and polish is as important as the glass types used. Mind you I've found that the Chinese scopes that use these expensive glass types (FPL-53 glass comes from Japan and costs 18x as much as normal optical BK7) do tend to be pretty well finished optically. I reckon if they are going to spend that much on glass, the figuring, polishing and quality control is done to a higher standard as well. There will always be the odd rogue that slips though though.

Is there a scope in there ???

Superb night here.

Added a swathe of galaxies, globular clusters and planetary nebulae to the above supernovae sightings. One of the best deep sky nights for sometime. Cold though so I've packed in and I'm warming up.

Snapped my "tools" mid-session. All the big guns got to play in the 12 inch dob tonight

Good advice there from Skipper Billy.

Have a browse around and don't feel that you have to post but also there is no problem at all if you do. There are no silly questions on this forum

One thing though, please could all posting be in English please ?

This is one of the forum rules.

Thanks

3 minutes ago, betelgeuse91 said:

Hi, I am wondering what are the differences between those two doublet telescopes:

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p9868_TS-Optics-PhotoLine-102mm-f-7-FPL-53-Doublet-Apo-with-2-5--Focuser.html

https://www.altairastro.com/starwave-102ed-r-fpl53-refractor-459-p.asp

Thanks so much  

I suspect they are the same scope under different brandings.

22 minutes ago, MarkAR said:

That's temptation beyond belief, I'd do it for free. Wonder how the Mrs would react if I end up with half a dozen mounts and scopes to test out in the garden.

Like mine did when I had a couple of ED150 refractors knocking around as well as my own scopes !

Another nice clear and dark night here.

Got the 12 inch dob out mainly to see if I could still see SN2020hvf in NGC3643 (Leo) and SN2020jfo in Messier 61 (Virgo).

In short, I have managed to spot both of these. 2020hvf is still magnitude 12.4 I think (same as Monday) and 2020jfo I feel may be a touch brighter than on Monday night but still a rather dim. I reckon it was nearly the same as a mag 13.6 star close to it so perhaps 13.8 or something like that ?

Apparently Messier 61 has hosted no fewer than 8 supernovae that we know of.  

Nice Sky & Telescope piece on these two supernovae here:

https://skyandtelescope.org/astronomy-news/supernovae-light-up-m61-ngc-3643/

I reckon the brighter of these could be seen with a 6 inch scope under a good dark sky. You probably  won't see the host galaxy NGC3643 though - that is magnitude 14.9 which is beyond my 12 inch scope under my skies.

Edit: Not 100% sure now about the magnitude of NGC 3643. I've seen a number of values between 13.6 and 14.9. I can't see it with my 12 inch scope tonight so I suspect visually it's mag 14 or dimmer.

2020hvf is still quite bright tonight (as SN's go !). About the same as it was on Monday night I think.

My 12 inch dob, this time with the 17mm 92 degree Explore Scientific eyepiece (94x) showed it and the fainter star close to it quite nicely.

What a super opportunity to be part of a great team

18 minutes ago, Jennifere20 said:

Yes done all that. Just got what I think is a very bright planet in my finder then I couldn’t see it through my telescope because my telescope moved 😩😩

If it is in the West it is most likely Venus.

Whatever fluid you use, apply it sparingly via a microfibre cloth or similar. Don't apply the fluid direct to the lens. Capillary action has a nasty habit of sucking the stuff between lens elements

18 minutes ago, Jennifere20 said:

Right. I’ve just aligned my scope on a church steeple. But when I’ve looked through the eye piece I couldn’t see nothing. What am I doing wrong? Does the telescope have to be upright because I had it to the side? 

You want to use your lowest power eyepiece for this (ie: 20mm or 25mm) and, in case you have one, don't use the barlow lens.

7 minutes ago, Stardaze said:

Thanks John, I'll venture out of the beginners section now that I've got my 2300 light years badge 👍

You don't have to post anywhere else but it's worth seeing what others are looking at 

That tiny crater is described as "relatively recent" in the Wikipedia entry for Albategnius so I guess it must be of impact origin, if that is correct.

I use a manual "hurricane" blower to remove loose debris from mirrors or lenses.

Over the years I've found the Baader Wonder Fluid applied via a micro fibre cloth the best for eyepieces and objective lenses. A bottle lasts for many cleans:

https://www.firstlightoptics.com/astronomy-optics-cleaning-protection/baader-optical-wonder-fluid.html

2 hours ago, Stardaze said:

As we didn’t get an official Bresser dob  owners thread,  what would a typical session for someone like yourself, who’s been doing this for many years, entail tonight? Have you a load of go-to’s that you generally find yourself flitting between? 

If you have a look in the observing sections (link below) you can see what people are or have recently been observing. Also "heads up" posts on interesting short term targets often go into the Astro Lounge or the Celestial Events Heads Up sections (also linked to below)

We are not picking on Bresser owners particularly - we have long resisted single brand sections and scope type sections on the forum because we have seen the negative impact it has had on other forums over the years

Here are those links:

https://stargazerslounge.com/forum/7-observing/

https://stargazerslounge.com/forum/239-celestial-events-heads-up/

https://stargazerslounge.com/forum/12-the-astro-lounge/

It is important to get the finderscope aligned with the view through the eyepiece (a low power one) in the scope. You need a distant target such as a chimney to do this in daylight. The target needs to be several hundred metres away or more.

It is very difficult to find targets in the main scope without the finder scope properly aligned - even the Moon !

The moon does not rise until 2:52 am tonight I'm afraid.

The Sky & Telescope Pocket Sky Atlas has a special chart dedicated to the Virgo / Coma galaxy cluster. It's quite good for navigating from galaxy to galaxy I find. Still possible to get a bit lost in there though !

I used to visit the Farringdon Road shop when I was on trips to London. It seemed like an "aladdins cave" back then and a chance to see and discuss mouthwatering equipment.

I bought quite a few eyepieces from them - mostly dealing with Pete Gallon I seem to recall. Dud Fuller was usually around somewhere at the back of the shop. They would take my older eyepieces in part exchange, which helped cash flow a bit !

I eventually bought a Fullerscope MkII mount and had a number of interesting phone conversations with Dud coming up with more and more varied excuses why the mount was taking longer than estimated to make. It was a bit like the Monty Python "Cheeseshop" sketch at times !

It arrived in the end and formed a very sold mount for the 6 inch F/6 Astro Systems (Luton) newtonian that was my main scope back then.

Good memories

3 hours ago, Neil P said:

Nice, I am biased but I do think they are some of the best looking scopes around. I have a 152 as well as the 115, only downside to them is the weight.

My 130mm F/9.2 is not too heavy - 9.2 kg with finder, rings and diagonal. The tube length has posed a challenge for mountings though. The AZ100 handled it well and now I have a T-Rex which is superb.

I imagine that the 152 is quite a handful, having owned one or two 6 inch refractors in the past. Superb optics though I'm sure.

When we can travel around again, come along to a star party and have a look through some larger aperture telescopes. The views can be quite startling

The difference between, for example, the globular cluster Messier 13 observed with my 100mm scope at 150x and my 300mm aperture scope at 150x is really marked in terms of both brightness and resolution. A completely different experience.