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What to image without goto ?


smr

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Hi all,

It looks like we're going to have clear skies tonight for the first time in a while. I've got a Star Adventurer mount and I really struggle to know what to image, I haven't got Go-to and I have no experience at star hopping. I've could shoot really wide at 50mm but I'd like to aim on a particular target with my 200mm lens instead, but I don't know what to. I have imaged M42 well but that was easy. So what would be a good DSO to image tonight, or if not DSO star clusters, is there something I can image near a bright star that I'd be able to see ?

Any help much appreciated.

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21 minutes ago, SilverAstro said:

I was wondering the same thing for tonight.

but those Messier are going to be a bit small with a 200mm lens though?? Assuming a DSLR.

I was thinking that. Yes DSLR, APSC but still going to be too small to bother imaging I think.

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Size-wise, I think you are going to be limited to open star clusters at this time of year.

M44 & MEL111 are the most obvious targets for this, but neither of those are particularly "near a bright star".

I suppose, find Arcturus & Denebola (the tail star of Leo) and from them find Cor Caroli at the apex of an equilateral triangle. Point the camera about half way between Cor Caroli & Denebola and you will be close to MEL111.

That would probably work well with a 50mm lens, but I suspect that a 200mm might give you "part" of the cluster on one edge of the field.

Best I can suggest ... sorry.

 

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Oh yes, M44 good thinking !  with little M 67 not far away and close to Alpha Cancer.

A bit off topic :  first I will be going for asteroid (51) Nemausa, mag11-ish  (between Regulus Alpha, and 31 Leo ) a second time to confirm from a week or so back.

And I have just noticed  (45) Eugenia near Denebola  Beta Leo. So I'll try for that as well  at a similar mag.

 

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I've noticed on Stellarium, at about 2am in the morning, the Elephant Trunk Nebula, Veil Nebula and a lot of other DSOs in that area are quite high up, why is Spring known as the Galaxy season then when there seem to be quite a lot of Nebula to image?

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39 minutes ago, Scott said:

Maybe the Heart and/or soul Nebulae ? Not sure how hard finding them would be thoughHeartandsoul.PNG.f05e40616cae9f54ef893b6303d8c278.PNG

I did think about trying them a week or so ago but gave up because I think moonlight. If I can make out Segin and CS Cam stars (excuse my ignorance! if they're known better as other names) it looks like the Heart and Soul is pretty much between them.

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19 minutes ago, smr said:

I've noticed on Stellarium, at about 2am in the morning, the Elephant Trunk Nebula, Veil Nebula and a lot of other DSOs in that area are quite high up, why is Spring known as the Galaxy season then when there seem to be quite a lot of Nebula to image?

The majority of people set up at sunset and observe/image from then - lots of galaxies atm. Often pack up before 2am if they need to work next day.

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14 minutes ago, Demonperformer said:

The majority of people set up at sunset and observe/image from then - lots of galaxies atm. Often pack up before 2am if they need to work next day.

ah ok so it's basically what is highest in the sky during reasonable hours which determines what are best to view / image during a particular season?

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I really don't know why but my alignment must have been off tonight. I levelled my SA earlier indoors and lined the reticule up properly, found Polaris after sunset, levelled mount and Put Polaris in the circle, went out when it was dark to fine tune Polaris and took a few subs of 20 secs, trails, then 10 secs, trails, made sure Polaris was in the right position but still trailing. Only using a short fov with my 50mm as well. It is a little bit breezy but I thought 10 secs and a slight breeze would be ok. 

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3 hours ago, smr said:

I've noticed on Stellarium, at about 2am in the morning, the Elephant Trunk Nebula, Veil Nebula and a lot of other DSOs in that area are quite high up, why is Spring known as the Galaxy season then when there seem to be quite a lot of Nebula to image?

Because they are only high up for about an hour before it gets light, and in late summer they are overhead at a civilised hour. :icon_biggrin:

Mainly because the 'best' time to image anything is during the season when it is due south at about midnight (UTC)

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7 hours ago, smr said:

I really don't know why but my alignment must have been off tonight. I levelled my SA earlier indoors and lined the reticule up properly, found Polaris after sunset, levelled mount and Put Polaris in the circle, went out when it was dark to fine tune Polaris and took a few subs of 20 secs, trails, then 10 secs, trails, made sure Polaris was in the right position but still trailing. Only using a short fov with my 50mm as well. It is a little bit breezy but I thought 10 secs and a slight breeze would be ok. 

I don't know the SA mount per se, but if you were getting trailing in 20 sec subs with a 50mm focal length, there was something seriously screwy with your PA. Based on my experience of PA, I would guess it is something really simple (something you don't even think about checking) like not making allowances for it being BST or the date needing to go in MM/DD instead of DD/MM, or battery not charged enough. Don't even know if any of those things are needed with the SA mount, but you get the gist of the sort of thing I mean. It will probably work perfectly next time.

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10 hours ago, smr said:

I really don't know why but my alignment must have been off tonight. I levelled my SA earlier indoors and lined the reticule up properly, found Polaris after sunset, levelled mount and Put Polaris in the circle, went out when it was dark to fine tune Polaris and took a few subs of 20 secs, trails, then 10 secs, trails, made sure Polaris was in the right position but still trailing. Only using a short fov with my 50mm as well. It is a little bit breezy but I thought 10 secs and a slight breeze would be ok. 

Once you’ve aligned it with Polaris you can do a little check by rotating the mount with the clutches loose whilst looking at Polaris  and the reticle. Polaris should stay on the outer ring of the reticle whilst you rotate it. If it still trails maybe the clutches were loose and it slipped? Or perhaps you knocked the mount? 

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2 hours ago, geordie85 said:

Just remember to re-check your polar alignment once you've pointed your camera at your desired target as moving the camera can disrupt your polar alignment, especially if you've got a lightweight tripod.

I believe this to be the source of my problems with the iOptron Skyguider Pro, very similar to the Star Adventurer. I can only manage to get about 2 minute subs reliably. Anything more than that is a throw of the dice on how much I've bumped it. Attaching the camera with a ball mount covers the polar scope so rechecking it after you've pointed your camera isn't always the easiest. You have to take the camera off, check it and then put the camera back. And who knows how much you've thrown it off just by doing that.

There are a few targets out right now to choose from for us widefield guys, but none that are necessarily easy to find by using a bright star as a sign post. You'll have to hunt for them taking multiple subs repeatedly to try and locate what you're looking for. I imaged the Rosette Nebula last weekend, but it took a while for me to find it. That was mostly due to my own screw ups. However, there are no nearby bright stars that will show up in a live view to guide you to the target so if you don't have GoTo, it's not exactly easy. Orion is going down now, Rosette Nebula, Heart and Soul, California is getting pretty low, Flaming Star, Beehive Cluster, Virgo galaxy cluster, a few galaxy clusters in Leo. Not a ton for us to spot with the widefield stuff, but a few things. Compared to what the deep field guys can image, we only have a handful of targets to begin with. The best part of the Milky Way will be up soon enough though.

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