John

34 minutes ago, Barry-W-Fenner said:

Well you do learn something new everyday! Thanks for the clarification folks!

 

Regards

Baz

Perhaps we need an "extreme observing techniques" thread

Worth bearing in mind that when looking for the really faint and elusive stuff, ANY light near your eyes (red or otherwise) will impair your ability to detect it. When I was looking for the Horsehead Nebula I needed to be dark adapted to a higher level than I have done before. I isolated myself from every form of light that I could for about an hour before try for the Horsehead and also observed faint objects to "limber up" as my eye got adapted. I turned my finder reticules off and just used the optical finder as well.

Extreme challenges need extreme methods !

It took me a long time to realise that there are some occasions when using very high power is a useful "tool" for certain tasks. For example, I had observed Uranus and Neptune in the past at 200x or so, enough to see them as disks. I read somewhere that it was possible to see some of their moons with my scope but very high magnifications would help tease these tiny points of light out of the background sky. Using 300x - 400x has helped me to see Neptune's moon Triton and Titania and Oberon. I would still like to see Umbriel and Ariel and also Phobos and Deimos at Mars 

The views of the planets themselves are not (usually) augmented by such high magnifications of course.

While they may not be the the most used tools in the tool kit, very high power eyepieces do have their uses.

2 hours ago, Stardaze said:

Do you use a coma corrector for your dob John? Be interesting too see how going to 100 deg will affect this aspect for me. 

No. I guess there is some coma visible at the field edges with my F/5.3 dob and the very wide angle eyepieces but I've not noticed it so far. Astigmatism from the eyepiece bothers me much more.

100 degree eyepieces are not something that everybody gets on with to be honest with you, regardless of how well they perform. Quite a lot of folks prefer the 68/70 degree apparent field, some are very happy with 40/50 degrees.

At least we have the choice these days

With regard to DSO's in other galaxies, the huge star forming region of nebulosity, NGC 604, in Messier 33 is reasonably straightforward to observe even with moderate aperture scopes.

I don't image either - apart from the odd phone at the eyepiece shot.

The shorter refractors will show some false colour (CA) and the longer ones less, or practically none in the case of the 80mm F/15.

The shorter refractors are good for low to medium power deep sky type observing but not so good and lunar and planetary observing.

I've owned the 127mm F/9.3 and the 152mm F/8 achromats (by Meade and Bresser now) and, personally, I prefer those to the shorter ones. The longer ones are harder to mount steadily though.

If you are considering as wide a range of specifications as you seem to be, it might be worth starting a new thread to kick around the options. This one is about the ScopeTech 80mm F/15 of course

You won't see that when the scope is properly focused on an astronomical target.

You need a 1.25" adapter for 1.25" eyepieces and the 2" adapter for 2" eyepieces. Don't put both adapters in the scope at once - they need to be used separately.

Just now, Stu1smartcookie said:

.... I was either going for a 127/1200 or 600 or the 152/1200 or 600 (bresser)... then this came into my view.....

 

That's a pretty broad range of options when you include the 80mm F/15 in with them !

Is the desire simply to try a refractor or do you have a specific aim in mind ?

That looks OK to me.

Quite a few mounts still just have one large locking screw and a smaller security screw so two large ones is a step up.

Just now, Alan White said:

 

Chaps, it's always good to be different.......

 

True !

My T-Rex alt-az is still on a steel tripod and is working splendidly

What, no wood ??????

A good, low cost, wide field eyepiece is the Maxvision 24mm. It has a 68 degree apparent field of view which means that it shows as much sky as a 1.25 inch eyepiece can and with enough magnification to keep the background sky reasonably dark.

There are other eyepieces with a similar spec and also good performance but the Maxvision is one that you might find within your budget. They are out of production now so you will need to find a used one but they are well corrected eyepieces for their price which is more than can be said of some of the low cost wide field eyepieces.

35 minutes ago, Stardaze said:

Do you get out regularly with yours John. Really looking forward to taking mine for a few trips, will just have to prepare a few things ready. Haven’t got an old suitable duvet really. A cheap kids sleeping bag will probably still work out cheaper than a dedicated bag.

A few times a year to society outreach events but not this year so far, for obvious reasons.

I do most of my viewing from my back garden which is not too bad for light pollution although there is some.

2 hours ago, Stardaze said:

Do you wrap the tube in a duvet? Remember seeing a dob with a seat belt mark in the classifieds and thought, there’s a warning right there. 

Actually I wrap it in an old childs sleeping bag that was my daughters when she was a lot younger. I don't use a seat belt on it though - it neatly fits between the end of the boot and the rear of the passenger seat of the car so it's not going anywhere.

1 hour ago, Stardaze said:

That would be pretty good John 👍

How do you find carting your 12” around? 

My 12 weighs about the same as a Skywatcher / Bresser 10 so it's not too bad. The tube section just about fits into the car with one half of the rear seat folded flat. The base goes next to it in the boot. The car is a medium hatchback.

At some point hopefully the SGL star party will start up again. It's held near you and while the skies are not perfect they can be pretty good. I've had some great fun there with 10 and 12 inch scopes (and even with smaller ones - the skies can be quite a bit darker there than they are at home)

One way to get an idea how a filter might perform compared with another is to look at the band pass charts for them:

The above is a couple of years out of date now but it shows that there are differences in band pass width, cut-off profiles and maximum transmittance between brands. Where the profiles are relatively close, the visual impact will probably be undetectable but the larger differences do make a difference that can be seen.

Here are similar charts for a group of UHC filters with a bit more information to help interpret them:

I have seen profiles for O-III filters which make them practically UHC status and likewise UHC's that are moving into the broadband territory.

Apologies if the above is "data overload" on filters

Forums like this provide a constant and responsive flow of feedback and opinions on equipment from those who actually own and use it. Far more influential and pursuasive than magazine reviews and advertising I reckon.

As the volume of positive information on a product builds it can be quite difficult to resist the feeling "well maybe I would like that better than the one that I have" and also quite easy to forget the positive experiences that you have had with your existing gear

In pre-online forum days the only information that I had on the relative merits of products or even that they might exist was through the pages of the monthly astronomy magazines and the very occasional and usually rather non-committal piece on "The Sky at Night" on buying equipment.

The first time I saw the name Tele Vue mentioned was in a small advert in the back of a 1980's edition of Sky & Telescope. I remember thinking what a cheesy name for an astro equipment brand and that their stuff was likely to be rather cheap and nasty 

What scope will these be used in by the way ?

Sorry if you have mentioned it somewhere but I can't recall it (getting old !)

5 minutes ago, Stardaze said:

Just clocked that, as it'a clearer on 365's site. That's next months present sorted then....

https://www.365astronomy.com/televue-bandmate-type-2-h-beta-premium-visual-nebula-filter-2-inch.html

Slightly worrying that the pic is of an O-III filter but the description is for an H-Beta.

If you buy from there, make sure you know what sort you are buying !

The closest focus on the scope is probably a lot further away than 20 metres - probably more like 100 metres or more.

13 minutes ago, Stardaze said:

And that's where my 'scrimping' falls down 😂

There's a Televue Bandmate O-III listed badly on a popular auction site. It's listed at 1.25" , at that price point, but, is pictured as a 2"? Only 'good' condition though, which puts me off...

Careful ! - the TV Bandmate and Bandmate II's are very different in quality. The II's are fantastic, the originals rather mediocre.

Astronomy equipment is much less expensive now than it was a couple of decades back.

I have catalogues from the 1990's and the prices compared to what you would give today for similar gear are, almost universally, a lot higher.

I have seen this mount before - it's been for sale reasonably recently I think.

Interesting that the amazing looking construction does not translate into a good mount to use.

I think I was quite tempted by it back when I was looking for a mount for my 6 inch F/12 achromat. I'm very glad that I didn't take the plunge having read Mike's assessment !