wulfrun

9 minutes ago, Optic Nerve said:

 if the secondary is rotated/tilted I guess that means any object I look at will appear tilted too?

No, it means you won't get the clarity and sharpness that you could have got. I bumped one of my newts, knocking the secondary quite a way out (it was not locked properly and I'd failed to realise). It didn’t make much difference, for most targets but for things like planetary detail it did degrade the view.

Try this guide, it's one of the simplest I have found:

https://garyseronik.com/a-beginners-guide-to-collimation/

I also suggest you pause for a bit and don't worry too much. You can follow the guide above methodically but I think the best part of it is that he explains, in simple terms, the "whys" and "hows".

41 minutes ago, Optic Nerve said:

https://imgur.com/a/QzvYuXi

 

Tried fixing the secondary mirror but just made it a lot worse

The mirror was loose at one point and I accidentally moved it so its probably off-kilter now. Maybe I should have gone with a refractor, this is frustrating

First couple of times is when you get your brains tangled up. Read the guides until it sticks in your head and you can look and know what you're seeing. Once you "get it" it becomes a simple and quick job, so stick with it! Ask any Newt owner, they'll likely tell you much the same. First time I did one of mine, I was faffing for hours. Now takes a few minutes, worst case, when I've bumped it (which happens).

Last night I managed (finally) to bag "the comet", nearly overhead. So faint I couldn't see it in the finder but I popped a 32mm Plössl in the Heritage 150P and found it after a bit of sweeping around. Just a faint fuzz with a slightly denser centre, I wasn't sure if I'd not landed on a galaxy in error so I went and checked on Skeye. Nope, no galaxy there but it's reporting the comet exactly where I was aiming. Result - just!

I spent a bit of time on M42 (has to be done, eh), just 4 stars of the Trap visible, then had a play on the moon with the new Svbony 8-3mm zoom. Things looked good down to 5mm but deteriorated after that. In fairness, the seeing was quite poor so I can't say it was the EP's fault. Tried it on Castor too, easy split at 7-6mm (a bit over x100), barely split at 8mm but again the seeing wasn't cooperating. Hardly a fair test.

1 hour ago, pipnina said:

So if I wanted the ground to be properly exposed, I should get a meter reading with the center of the frame pointed at the ground, then frame my shot? Works for me if that's the case, I was probably exposing for the sky.

That's about right, yes. Assuming your subject is "typical" (not a black cat or a white sheet etc), you need a reading where it occupies most/all of the central region in the frame. Either lock that exposure or note the settings it says and set them in 'M' mode.

I admit never having done Astro (beyond once or twice lying an SLR on its back and leaving the shutter open for 30 mins or so for star trails) so I can't offer suggestions for it. Reciprocity-failure is very real though, if you can actually get some sort of metered reading (the built-in meter won't do it), expect to use double and upwards.

One thing to mention, alluded to above...regular (automatic) printing processing is geared to "normal" photos. Meaning they expect a shot to be 18% grey on average. Any astro shot, which should average to almost-black, will get blown out to a grey average in printing unless they know not to.

23 hours ago, pipnina said:

...Weirdly enough even normal photographs I took came out very poor, despite using the camera's inbuilt metering system (and setting the ISO on the camera body to the 400 declared on the film can). Maybe some film photographers here might know what's going on...

The AE-1 has a centre-weighted metering system, in the daytime photos you have a lot of bright sky and I'd bet that's fooled it. In the days of film cameras, modern evaluative systems didn’t exist and you'd learn to think about when to accept its readings and when to "interpret" them (i.e. override and correct it!).

5 minutes ago, LDW1 said:

I am a wide field guy with my eyepieces ie 76° at minmm so it matters to me but the zooms are great for what they are and how I use them. Remember they are a zoom, for most astronomrs not a main ep, on most nites, you may differ.

I agree with you completely, I also use a zoom as a tool for use when appropriate. I also like wide-field, my other EPs are at least 60-degree and some are 82-degree. I was merely pointing out the narrow FOV at the longer end to the OP.

Of the two, I only have the SV135 (7-21mm) and for the price there isn't much to complain about. It's reasonably small & light and the zoom is fairly smooth. Optically, I haven't noted any significant issues. It has (possibly) the narrowest FOV at the longer end, compared to other zooms but that may or not matter to you. A wider FOV will cost a fair bit more.

Postie brought me this, I succumbed to temptation:

EDIT: the cloud-gods, have of course, exacted payment. I'll post my thoughts in the ongoing eyepiece thread...when I've used it!

I have one Nirvana, the 16mm and it gets frequent use in all three of my scopes (f/4.4, f/5 and f/8). I like the wide field, particularly for longer "dwell time" in the two untracked scopes, i.e. less nudging. Personal taste and depends on what you're looking at too. I also have another 82-degree in 9mm (Nagler), that also sees a lot of use. Again, personal opinion but using narrow FOV eyepieces seems like looking down a straw once you've used wide ones regularly.

I had the 150PL out for another session observing Mars. Damn cold out but with a 9mm plus 2x FE  (x266) I had probably the best views yet with some reasonable clarity and better-than-usual steady seeing. I can't usually use that high a mag successfully. I tried a variable polariser since it was still a bit bright but it didn't help, I got my best view with just a Neodymium. I could see definite colour differences, bluer/redder areas but didn't note any sign of a polar cap. No doubt the views were helped by a freshly-collimated scope, which turned out to have needed it - it was badly out, oddly so!

I spent another half hour or so splitting a few doubles and then having a good look at the Trapezium. Rather chuffed with that, since I just managed to spot the 'E' component for the first time. Sadly not the 'F' though.

I finished up with quick look Jupiter but the view was disappointing since by then it was getting a bit low and badly placed (streetlight!). After that I gave up due to being too cold.

@Stu

 If that were mine, I'd be sorely tempted to put a stack of cannonballs beside it and shout "turn those lights off...or else!"

The Telrad looks like it's ready to launch!  😀

Depressing isn’t it. We make lighting more efficient, so we use more of it instead of utilising the efficiency to cut power & cost. Maybe we ought to have banned outdoor LED lighting rather than banning the old-fashioned "bulbs"?

I've had local streetlighting largely replaced with LED. I'd say it's overall slightly better-aimed but it's brighter, not filterable and the point-source LEDs have worse glare.

Time for some standards to be introduced for ALL oudoor lighting? Not holding my breath!

29 minutes ago, Hedlund said:

I have android so i downloaded it from the playstore.

Unless it's changed recently, that version may not work. Get it from the Skywatcher site. My version is Pro 1.19.15 but I think there's a newer one too, not updated mine because it works so I'll leave it alone.

I might also be wrong but from the screen-grab your WiFi is already connected to the dongle...the ! symbol next to the WiFi symbol suggests it is anyway.

EDIT: where did you install the SynScan app from and which version is it? Some are known not to work with later versions of Android.

Condolences from me too, he was a familiar name to me.

Just found this on beeb, I wasn't out so I didn't see it:

https://www.bbc.co.uk/news/av/uk-england-64220964

16 minutes ago, Shontay7 said:

off to read about Collimation!!

Try this guide. Simple, no nonsense and aimed at the beginner:

https://garyseronik.com/a-beginners-guide-to-collimation/

Yes, quite a few times! Stick your head out for a quick look and think "ooh look, stars, that's promising". Then go out properly for a bit longer and think "maybe not then" when you realise only the brightest are poking through.

53 minutes ago, spacedobsonian said:

A bit off-topic but they made a heritage 114p?

Yes, the Heritage 114P Virtuoso. Not sure if the OTA is available in any other mounts:

https://www.firstlightoptics.com/heritage/skywatcher-heritage-114p-virtuoso.html

(Mine has red tube, not black as shown)

I have a Heritage 114P, it has a collimatable secondary but the primary is fixed. I've tweaked the primary as per @Peter Drew's method above and made sure the secondary is correct. I've checked it now and then and it's not needed any adjustment since, so I don't think the fixed primary is an issue. Probably helps that the mirror is relatively small and lightweight.

2 hours ago, Mdennis said:

Got my new Skywatcher 150 P and I'm really happy with it. Got some good views of Jupiter and its 4 main moons last night so I'm delighted with my choice. I know the eyepieces that come with it are reasonably good but could someone recommend decent quality eyepieces and maybe a good quality Barlow lens.

Good choice, it's a pretty capable scope. I have the Heritage version, same mirrors. How much do you want to spend? Usual recommendation is BST Starguiders, around £55 apiece. Your scope is fairly "fast", so the best BSTs are likely 15/12/8/5mm although  you can get away with fewer, say 12 & 8mm plus Barlow (there's a 2x in the same BST range). The 5mm will also work well but the 8mm + Barlow would probably be just as useful.

I'd suggest a 32mm Plössl as a lowest-power, not expensive and it'll work just fine, Barlow it for an effectively-16mm. EDIT: might give too much eye-reliew Barlowing a 32mm Plössl, try it though.

If your budget is more generous, look at OVL's Nirvana range. Much wider and also good value step-ups, I have a 16mm and it works well so I'd expect the others would too. EDIT2: 16 & 10mm and a 2x Barlow would give useful choices in Nirvanas.

I don't think there's a definitive answer to your questions, mainly because you'll find it hard to compare "apples to apples". A good quality zoom will be very close to a good quality fixed EP, probably too close to tell under most circumstances. Likewise, a good quality Barlow will be almost indistinguishable from using an EP of half (or whatever) the focal length. Modern optics are pretty good and it's more a case of "technically" inferior for a zoom or with a Barlow. Provided you steer clear of the likes of a no-name fiver-off-Ebay Barlow.

One thing with most zooms though, they tend to have a narrower field-of-view and it's narrowest at the longer f/l end of the range (annoyingly). On the other hand, if you have a zoom you can set it to whatever is the perfect f/l for your situation. You can get 4 BSTs for the price of the well-regarded Baader Hyperion zoom (roughly speaking). Which is better is largely personal preference.

Incidentally, photographers tend to shun zooms based on historical performance. Early photographic zooms were noticeably poorer and the reputation has stuck. Nowadays the penalty for a camera zoom lens is more about f-stops than image quality.

I think the idea of three or four EPs really only works if you have one scope and live somewhere with consistent conditions. I have three scopes, ranging from 500 -1200mm f/l so some EPs aren't suitable for some scopes. Hence the Barlow, focal-extender, zooms and half-dozen fixed EPs. Between them I can find the optimum for most targets, scopes and seeing conditions.

On 26/12/2022 at 20:46, Simon Stewart said:

I'm quickly narrowing down my choices, and also got the skywatcher heritage 150p and the classic 150p, both on Dobsonian mounts. Any thoughts would be more than welcome. 

Rough comparison of those two:

Same aperture so same light-gathering ability. No advantage to either in that regard.

The Heritage collapses down to about 1/3 the size of the Classic, so easier for storage & transport. However, the Heritage needs a sturdy table to use it on and the Classic doesn't.

The Classic is f/8 which means it's more suited to higher magnifications and you won't need eyepieces that are as well-corrected (i.e they're cheaper) compared to the Heritage, which is f/5. The downside to the Classic's f/8 mirror is that the maximum field of view is narrower than the Heritage can achieve.

One thing the Heritage does need is a light-shroud (keeps dew off the secondary as well), easy & cheap to make one though. The Heritage also has a cheapo helical focuser...it works but some folk just don't get on with it.