ONIKKINEN

That's a lot of stars in one picture. Almost tempted to test if DSS has a stroke trying to count the stars with 5% detection threshold 😃.

Curious black spots on an otherwise very busy image, dust lanes and molecular clouds in the plane of the milky way i assume?

4 minutes ago, Don Pensack said:

However, where eyepieces are concerned:  Inexpensive, well-corrected to the edge, widefield--choose any two.

Like most things in the hobby, the wallet and the wallet holder disagree on whats best 😁.

I would hate to make a "just fine" decision and have to stick with it so ill probably avoid the more affordable ones for now. As i was already considering the Hyperion zoom + maybe one other affordable eyepiece i realize the TV panoptic 24mm would be "just a bit more" (i will pretend its close in cost, although quite a bit more). That would be ideal for me, well made and the widest 1.25 inch eyepiece there is. I hated the idea of buying TeleVue at first, but perhaps that's the direction ill be going anyway... Thanks for the insight!

18 hours ago, Catanonia said:

Here is the 1st 10min sub (preview from asi air) with a lEnhance 2inch filter

I would take the filter out, as it works against you pretty severely in this case.

The l-enhance cuts out almost all of the visible spectrum, except for the common emission lines of H-alpha beta Oxygen something something etc. The IFN is reflected starlight from the integrated flux (hence the name) of the stars of our entire galaxy, and since starlight is mostly white and falls to the area that your filter cuts off you really are sawing almost all of the nebulosity off. Just shoot without the filter and take normal RASA length subs and i think you would already have the IFN visible quite well.

12V for appliances is just a naming scheme, the voltage ideally would be close to 14V in many cases, so no you cannot damage your stuff with that! 13.8V is pretty much ideal for 12V electronics 👍. You would probably not want to go much over 14V though, and definitely not close to 15V as this could start damaging sensitive electronics although still quite unlikely for short periods of time.

If a car battery reads 12V with the engine running you should change it immediately as it will die very soon, car batteries with the engine running are right around 13.8V with a good condition battery in warm conditions. Like car batteries and other appliances with "12V" in mind a voltage of over 13V would be desirable. In this way the 12V naming scheme really means "do not go under 12V".

1 hour ago, Iem1 said:

I quite like the starless image, but I have not figured out a way to blend the stars back without introducing a grey cast to the image and blowing out the core too much, working on that!

Did you follow the StarXterminator page instructions to create the starless-just stars-original layers? Goes like this:

If you want to create a layer with just the stars so they can be processed separately and added back in later, do the following:

• Duplicate the target layer twice
• Process the top-most layer with StarXTerminator
• Duplicate this layer, then make it invisible
• Select the first starless layer and set its blending mode to "Subtract"
• Merge this layer with the one below – this is now the layer with just the stars
• Move this layer to the top and set its blending mode to "Linear Dodge (add)"
• Make the remaining starless layer visible again
• You should now have three layers: the original photograph, the starless photograph, and the stars themselves

After this, hide the background layer (not needed anymore, but keep it for now to compare), set the blending mode of the starless layer to be "screen" (starless layer is the topmost layer if you followed the instructions). Then unhide both the starless and stars layer to have both visible at the same time. It should look the same as the background layer as it is created from that.

The just stars- layer does not have any background at all, it is set to 0 by StarXterminator. The only signal there is the stars and possible bloat around the stars if any remained after running the filter. You must use the starless layer to set the background to the level you like. I personally dont think the background should be 0, or even that close to 0 but it depends on the target. Galaxies have no defined "edge" in reality so a grey-ish background will look nice as the galaxy edges just sort of blend to the background. Play around with the black end of the levels to set it where you want, but i think values between 20-30 are typically the nicest.

A bahtinov mask is better than nothing to find focus IMO but its not the optimal way. Looking at HFR values on a computer/mobile device is a much better way to reach critical focus. Since you run unguided i don't think that's possible for you right now? But it might actually be better to eyeball focus with the camera screen on whatever is the max zoom mode on a barely noticeable star than do a bahtinov mask focus, although when i did DSLR shooting i found it way too fiddly and just accepted whatever focus the bahtinov mask reached.

If technical details interest you, have a look at this site: https://www.photonstophotos.net/. You can filter the cameras you want to compare in the various tests done there. But generally Canon cameras are quite weak from a raw sensor specs standpoint and Nikon cameras are better. Sony cameras are also good but here you have whats called a "star eater problem" where there is noise removal in the raw frame that can remove small stars from the image. That feature cannot be removed so some research should take place before buying a sony camera.

Also, have to agree with Olly above. Dedicated astro cameras are MUCH better than DSLRs and the price differences are getting smaller by the day. I would say that get the DSLR if its less than 500e (preferably much less) but otherwise dont bother and jump straight to the dedicated astro camera train.

16 minutes ago, Don Pensack said:

The assumption that paying more money means the eyepieces will work at a faster f/ratio is a false one.

Eyepieces have to be designed to not yield astigmatism in the outer field at f/4, and very few eyepieces are.

This is one of TeleVue's claims to fame.  I would also add Pentax, Nikon, Leica, and Zeiss to that list.

So far, very few Chinese eyepieces make that list.  The APM XWAs do well at f/4 (and the other brand names for the same eyepieces).

The APM 30mm Ultra Flat field is also a good performer at f/4.

 

Every eyepiece design has a "critical f/ratio" below which edge of field astigmatism increases.  Explore Scientific has not really aimed their designs at the f/3-f/5 market

except the 92° series, which does work quite well in faster f/ratios.  The Orion LHDs also work fine at faster f/ratios.

 

I've explored many lower-priced eyepieces in scopes of f/3.45-f/5.18 (all coma corrected).  Baader does not make anything appropriate, though they work OK at f/5.1 (f/4.4with Paracorr).

All the older designs: Ramsden, Huygens, Kellner, Plössl, König, Erfle, Abbe Orthoscopic, Monocentric, should be avoided if you are looking for correction to the edge.

 

 

Looks like all of the good ones are quite expensive, some food for thought... Perhaps i should say that a compromise of "good enough" should be noted and perfect correction to the edge not being necessary.

I wonder if the other APM ultra flat models also work well as i would ideally avoid 2 inch barrel sizes just for simplicity's sake? I would say that my 19mm flat field (an apm clone) works at least decently well to a point where it doesn't bother me.

3 minutes ago, PeterW said:

…. Like eyepieces I have several pairs of filters now… though I am trying to ”optimise” (read get rid of the ones I don’t absolutely need). By wedging 1.25” filters into the eyecups with 5mm foam sheet it saves me needing to buy any 2” filters!

 

Peter

Love it, what a simple way to save a hefty sum of money.

3 minutes ago, John said:

I've seen the Eastern Veil with 11x70 binoculars on an excellent night here and under really dark Dartmoor (Devon) skies but not in smaller binoculars, thus far.

 

I don't think I've seen it at all. Suppose it would be visible from Bortle 6 through the VX8? Its a 20-30min drive away so not that difficult to do.

I keep reading about this notion that fast telescopes require some sort of different types of eyepiece to work well, for instance the explore scientific 68 degree ones say they work well at f5 and above, which my scope is not. Actually my scope is more like f4.2 with the TS maxfield 0.95 coma corrector so worse for this case. Are some eyepieces really so picky about this? I would assume if i pay more than plössl-type money for an eyepiece it would work with mine, but i could be wrong.

I have 3 eyepieces at the moment, all Omegon branded. Omegon Cronus 7 and 9mm (i think 60 degree) and an Omegon flatfield 19mm 65 degree. I think the flatfield is like any other "apm clone" out there as it looks identical to many others from other brands. I also have a good quality 2.5x barlow to extend the range.

What i know i am missing is the extremes and something in the middle. Maybe a 5mm for planets and close ups of the Moon and a 25-30mm wider field eyepiece for rich fields and making it easier to find stuff? Also what i could get is the hyperion zoom eyepiece which sounds very convenient, but lacks the wide fields because of the narrower field of view in the lower power range. Also i keep reading of this "fixed focal length eyepieces are better" type of thing compared to zoom eyepieces.

I am woefully under educated on visual stuff because for some reason visual always had a backseat for my telescopes. Last night i had a great time at the eyepiece with no cameras involved so i am looking to complement that with kit that seems missing from my setup. The budget would be somewhere around the price of the hyperion zoom plus or minus a bit since its not an exact number. I realize i could get just 1 great eyepiece, 1 zoom eyepiece or a few decent ones but i have no idea which ones are the best bang for my buck.

Just tested under the stars and found the same to still be true. 50mm and thereabouts works fine. Coma is still present at the edges but im not sure whether thats the eyepiece or the corrector or both. Also worth mentioning that looking at the Maxfield 0.95x spot sizes you can see that there just is residual coma that is not corrected. Still i think this nicely frees up the inner 50-70% of the view to be visually coma free at a glance.

Curiously i found that i could put a barlow in the eyepiece holder and the barlowed eyepiece was also much better than the barlow without a comacorrector, coincidence perhaps? For whatever reason i had thought that comacorrector + barlow is a big no no.

Ended up bagging a lot of the aforementioned targets this night!

3 hours ago, tripleped said:

You are correct in that brighter globulars in addition to open clusters are still pleasing targets in light polluted skies. I also live in Bortle 8 so lots of experience with this. With Auriga now rising in the east open clusters M36, 37 and 38 are good examples.  The double cluster, M52 and of course M45 also great choices.  Nebulas are hard to impossible except of course for magnificent M42 in Orion.  With planetary nebula the only one I can see in my skies is M57(ring)     You can definitely see M31 (andromeda) but mostly just a small bright core with a little surrounding fuzziness but at least U can see it !  M81 (Bodes) will look faint but visible.  I’m sure there’s more but those are the ones that come to mind. Hope that helps!

M36/37/38 were actually pretty nice. Lots of faint stars nicely filling the view at 93x and at this power the background no longer looks all that light polluted. Almost looks like cobwebs at a lower power of 44x? Perhaps its because a lot of the stars are averted vision and are coming in and out of view. Double cluster was very pleasant to view, a really photogenic open cluster! First time viewing M42 this year and of course it deserves the name "great" orion nebula. Lots of nebulosity surrounding the trapezium, and some semblance of shap even.

2 hours ago, Ags said:

I can highly recommend doubles as an observing choice in Bortle 8++ conditions. If you can still view Lyra from your location, it has a number of lovely doubles near relatively bright stars - all very easy to find. You can download the PDF in my signature which has a number of finder charts. Cassiopeia is also a rich hunting ground with plenty of bright stars acting as signposts.

I opened your PDF thinking there is like a handful of these. Turns out there there is an awful lot of double stars since you wrote a 250 page guide on them 😅. Im going to have to take this in chunks, maybe per constellation? Anyway thanks for the link, im definitely looking my next sessions targets ahead of time instead of trying to browse it on my phone at -8 and windy! I ended up taking a go-to to Almach, since it was in the synscan list and high enough up to see. Nice and clear separation at 93x, perhaps was even visible at 44x but im not confident enough on that to say it was separated.

2 hours ago, Captain Magenta said:

I used to live not far from London, also B8, and would generally look at the following targets:

- Polaris and Polaris B: Polaris B a beautiful blueish pinpoint near the Pole star, I never tire of looking at it

- The Mizar/Alcor system, a lovely arrangement including Mizar as itself a nearly-matched double

- Castor, a very nice double

- As a challenge for the skies, try for M81/82 and M51 near Ursa Major ... I could sometimes get those even from near London, just smudges but from B8...

- Epsilon Lyrae, the double-double in Lyra

- M57 Ring Nebula also in Lyra, should be bright enough to see

- Uranus, about 44 degrees up at 11pm from where you are - no doubting it's a planet, a disc

- try for M36, M37, M38 in Auriga

A short selection of what I'd try for, I'm sure others will suggest more interesting doubles to attempt.

Hey hey, Magnus

PS I would add @Stu has much more experience than me from these sorts of skies, although he's recently moved much darker, but I'm sure he can make some great suggestions too.

Polaris B was very surprising. I kept looking and changing between 44x-93x-120x and i was sure i cant see it but then i noticed the little companion! It was there all the time, maybe i just thought it was a speck of dust or a reflection? Once i had seen it once i could spot it easily at 93x. Very nice difference in brightness. I also think i saw M51 flicker in and out of view. No shape and nebulosity but the cores of M51 and the companion of the tail were roughly where i would imagine them being so perhaps it was M51? Did a go-to to M81 but at this point synscan decided that M81 was in fact on the ground next to me 🙄. Never did return to try this after troubleshooting that experience. Also never figured out why this happened, but it went away after redoing star alignment from park.

Lyra was getting a bit low in the sky at this time and was very milky. Wasn't able to see much of anything in there, but i will check again one day.

But the highlight was obviously the Moon tonight. The atmosphere got very stable and clear for a while there and i was able to observe at 300x without really any noticeable downsides. The PV 1/10 VX8 has never let me down with knife-sharp views of the Lunar terminator! I probably could have gone deeper but i ran out of eyepieces and barlows to do that.

Also after having mostly done astrophotography i find it very freeing to not have to deal with 40 gigabytes of files on a memory card after the session. The session is done and that's that, i think i could get used to this 🤔.

1 hour ago, Captain Magenta said:

I admire your dedication at 0230!!!

Sleeping can be done also when cloudy, unlike observing.

Appreciate the comments! 

At the moment going through some cursed mount diagnostics as the mount does not go to the correct coordinates. It goes to sonewhere random and says its there... Maybe i need a manual alt az with 2 moving parts 🤣.

Ill try to slew manually and find some of these.

22 minutes ago, assouptro said:

I’ve been looking at these 

have you got one? 
are there any issues with drivers or software? 
cheers

3 months owned one. No critical issues yet. Only slight nuisance with drivers is that sharpcap runs at very low framerates = 0.2fps even. Irrelevant for deep sky and other software like nina are as youd expect from any imx571.

Other than that no issues with sofrware.

2 minutes ago, Stuart1971 said:

Including VAT for you, but it has to be added for us in the UK when we buy from EU…

I meant this one: https://www.aliexpress.com/item/4001359313736.html?spm=a2g0o.productlist.0.0.6f047164JGhOx6&algo_pvid=88c7fc7f-59b2-4b58-9bdc-a75b08237944&algo_exp_id=88c7fc7f-59b2-4b58-9bdc-a75b08237944-0

Comes from China directly so VAT for everyone. When i bought mine i was not charged VAT at the checkout but i think the rules changed just after that and now you pay VAT to aliexpress. You never have to pay VAT twice, if you can prove the value of the item and the already paid VAT with an invoice which you obviously can.

You might enjoy Scott Manley on YouTube. He does general space related videos and uploads regularly.

Looks like its going to be a short/unknown length of sudden unforecasted clear skies tonight judging from current weather. Not long enough for me to drive to better skies but since its been weeks since i last saw anything im tempted to set up just outside my flat for a short(?) session at the eyepiece. I find that i have sudden breaks in cloudiness like these far more often than actual fully clear nights and maybe i could use them for observing. Conditions will be: Bortle 8 and no way to hide from local light sources such as street lights and city lights in general since i will be setting up on a fully lit parking lot just outside my flat.

The Moon is an obvious target and will be nicely positioned in a few hours, but other than that my knowledge of viable targets are lacking. I guess stellar targets such as doubles (never tried), maybe globular clusters? Open clusters perhaps? Planets have already set for this year, not that they were very good to begin with being so low in the sky.

Observing would be done with a VX8 on a Go-to mount.

7 minutes ago, Stuart1971 said:

Yes plus VAT and import duties….👍🏼 For us here in the UK

Including VAT!

4 minutes ago, Skipper Billy said:

There are loads of used mono cameras about - there is an Atik16200 with EFW3 filter wheel and a full set of filters for sale for less than £1800 on a well known astro sales site. Find me an ad for a used ZWO 6200 or 2600 for comparison 😉  (The Atik has been for sale for quite some time and not sold!)

Used prices are not really fair as a comparison since there are so many variables.

A brand new IMX571 OSC camera is 1350€ btw.

7 minutes ago, Skipper Billy said:

Apart from mono being quicker than OSC, able to capture true narrowband, easier to process, smaller file sizes and being MUCH cheaper than OSC (there are some amazing used mono outfits for sale for crazy low prices as people jump to OSC) - I can't think of many reasons 😉 

Mono cheaper than OSC?

Looks like its the other way around unless i missed something.

Edit: i find it interesting that 3 users posted the same observation at the same time.

1 hour ago, Laurieast said:

We are spoilt by being kept relatively warm with the gulf stream. Anything less than -5C and everything stops!

I would actually rather be in a dry -20 than a humid +1. Thats the worst type of weather IMO.

-20 and windy is where i think again about going outside. Probably will still go after thinking about it.

11 hours ago, Louis D said:

I use the GSO CC with a fixed separation of about 75mm.  I simply added a 25mm M48 spacer ring between the included eyepiece holder and the optics nose piece.  As long as you're within 5mm of the design distance, it's hard to perceive much residual coma.  Generally, eyepiece field curvature and edge astigmatism drown it out.  I've only had to parfocalize one eyepiece with it, the 12mm Nagler T4.  It focuses about 20mm below the shoulder, so I added a 20mm M48 ring to the 2" skirt along with 5 4mm thick O-rings of 50mm ID.  When you're 20mm out, the residual coma is quite apparent.

I have no idea if the TS Maxfield CC will be as forgiving as the GSO CC, but it might be.

Keep us informed of your experimentation in case someone else wants to try it in the future as well.

Lacking clear skies at the moment i figured out an actually decent way to test coma from home. I pointed my telecope to a balcony about a kilometer away that conveniently has Christmas lights put out on a pretty wide area. My 19mm 65 degree Omegon flatfield eyepiece nicely covers the entire line of christmas lights end to end and makes it quite easy to judge coma at a glance. Sure im looking through dirty windows that are far from optically good but better than nothing.

I found that its not all that clear what the effect is with small variations. With the adapters i have on hand and just by lifting the eyepiece a bit i found that anywhere from 45-60mm from the corrector threads to the end of the eyepiece barrel is similar. 70mm was clearly not good, as was under 40. Ill have to test again with real stars as even at 44x power the Christmas lights were not point sources. Still good to know im in the roughly right area with the adapters i have. And of course just to test if this method is good at all i took the comacorrector out and there is the normal f4.5 strength of coma even quite close to the center of the field which is to be expected.

34 minutes ago, Enceladus Dan said:

For the deliberate Polar misalignment I read it and get the idea but didn't quite understand the how. I assume it's the altitude is slightly out so it corrects one direction. 

Regards

Danny

Pretty much just that.

Just align to an error of maybe 5-10 arcmin and there should be a consistent drift to just one direction in DEC. Run guiding assistant and see which direction the drift is to and set DEC guide mode to counter that. This way in theory your DEC backlash is in check because the gears are touching like in the RA. Also this relies on DEC balance being slightly out. Perfect balance will have your DEC axis wobble between the backlash gap.