EAA Newbie Report - Double Cluster

[vineyard]

Returning to astronomy after decades away, the biggest thing I have been struck by is the huge changes in what technology (hardware & software) allows us mere amateurs to do.  (For example, I can now take AP images from my back garden that I could not even have imagined in my younger years: thank you plate-solving, INDI, CMOS, dithering, multi-star guiding, stacking, post-processing etc etc!).

It was in this spirit of curiosity that, while rummaging around, I came across NV technology on CN & then even noticed it in its own ghettoised prison-yard on SGL (no NV posts allowed elsewhere - strictly verboten!).

While intrigued by it on paper, I've always been one to make my own mind up based on direct experience.  And so nothing much more came of it.  Until @GavStar put a PVS-14 up for sale.  Since we're in the same city, he v kindly agreed to let me come & try-before-possibly-buy.

I went with zero expectations.  The night was SQM 18ish, clouds were drifting in from the North.  But when I put my eye to the NV at 1x with just a simple 1.25" long-pass filter in (as would be used for planetary), it was breathtaking - a MULTITUDE of stars, with even the clouds drifting across stars (which you couldn't see with the naked eye) seeming like a scene from a Japanese woodblock.

There followed a trawl through various nebulae with an Ha filter in place while dodging clouds.  And frankly I saw things (NAN, Pelican, Pacman, Butterfly etc) that there is NO WAY I could otherwise have seen from a conventional backyard in light-polluted London.

Now I also wanted to test the NV with more "mortal" equipment.  So Gavin kindly put a TV76 on an AZGTI with an 18.2mm Delite and the PVS-14 & a normal long-pass filter, and we pointed it at M13 in Hercules.  I think that was the single most powerful demonstration of NV-enabled visual astronomy for me.  I had just been looking at M13 about a fortnight ago through a 180mm MakCass & had been v happy to be able to resolve a few pinprick stars amidst the fuzziness of the core though an 18.2mm.  And the little TV76 just blew that away...done.  (I can't wait to see what the 180mm MakCass will show - if its the same proportionate impact, then maybe I'll see what a 400mm+ would show?).

About ten nights back it was clear for a few hours.  I was in the middle of capturing some AP data with my TV76 so I didn't want to change its configuration then.  So while that was clicking away, I thought I would just give the PVS-14 a run-out.

On an old Telementor 2 (63mm, f/13) with a TV40 plossl & an 18.2mm Delite.  With a bog-standard Baader Moon & Skyglow filter (I don't have a planetary long-pass filter yet).

I knew that this would not be a fair test - everything about NV says the faster the optics the better the impact.  So here was a small aperture, s-l-o-w setup w an ok-ish broadband anti-LP filter (its not an Astronomik CLSCCD).

I pointed it at the Perseus Double Cluster.  And did both non-NV and NV at both 40mm and 18.2mm to compare.

The difference between the NV and non-NV was PALPABLE.  In non-NV only a small handful of stars were visible, and you would have to have relied on an atlas to say to yourself yes those must be the clusters (tbh it just looked like a few nondescript points of light).  With the NV in place: yep those are clusters.  I took a couple of quick photos with my smartphone (attached, 18.2mm and 40mm) - literally just holding it over the EP as still as possible.  These pictures won't win awards but hopefully give a sense of what these devices can show.  I can assure you that non-NV there were not that many stars visible (same scope, same EP, same filter, same night).

So this has just whetted my appetite for what more can be done with this kit.  If a 63mm slow scope shows this...I'm already concocting some what-if ideas to try different permutations.

There is ofc a role for both non-NV & NV visual astronomy.  Sometimes its nice to see the vast blackness and just a few random stars - and sometimes its nice to see just how that vast space isn't as empty as you think through your own eyes (rather than a multi-hour stacked AP).

So two takeaways continue to sit with me.

1.  This is visual astronomy.  I have nothing against AP or live-stacking (& in fact v much enjoy the former & am beginning to explore the latter).  But NV is visual - the user experience (UX) as techies would say is v much visual.  No computers, no capturing, no stacking or processing, changing EPs in realtime to explore objects in realtime.  This is a visual UX.  (Yes a battery is involved, but tbh if someone does non-NV visual with digital setting circles, or a go-to mount, or a tracked mount, they're being electronically assisted...and even if someone does old-school star-hopping only and finger-pushing only, then I'd wager the lens/mirror they're using will still have been critically reliant on electronics-driven processes at some stage to get to the required level of precision! This ring-fencing of NV astronomy as “electronically assisted” is bizarre & short-sighted).

2.  At the risk of seeming like a heretic, if you live in a LP urban/peri-urban environment, and want to do visual only, are you actually better served getting a v nice achromat & an NV device, instead of a high end apo like a Tak (or any other make!) or a big heavy dob?  That will probably put the cat among some pigeons - and don't get me wrong I appreciate quality as much as anyone else - but having seen first hand what this device can do, I'd rather have this and a Vixen 102M than spend the same amount of money on a 4" Tak tbh.  (Ofc if you also do AP it is completely different, or if you are in dark skies then it will be different...this is specifically if you are in light-polluted urban/peri-urban skies where you will never be able to dark-adapt properly and yet you want to be able to see deep or faint objects without having a big beast of a scope).

Sorry this is quite a long post (and a delayed one - ten days after the actual observations!), but figured a first-hand account of a sceptical newbie may perhaps be of help to others considering on the sidelines.  

Cheers

[PeterW]

Welcome to the dark side…. helps the fight back against what London light pollution throws at you! @GavStar coverts another hapless observer! Go and get a faster scope (or do the afocal “trick” to speed things up) and some longpass/hydrogen alpha filters… you know you need to!

Peter

[vineyard]

Indeed re the induction to the Dark (actually No Longer So Dark) Side.  Gavin has a lot to answer for b/c yep Ha & 642nm filters are en route....as is probably a TV55.  I still need to get my head around the maths on afocal, and also have a 0.5x reducer which I want to experiment with.  

Reading the reports of the UK pioneers in this 'ere ghetto, as well as the CN folks, is whetting my appetite.  I know I've already seen things I could not imagine from the Big Smoke - glad to be aboard this ship!

[GavStar]

Moi? 😉

Very pleased that you are happy with the pvs-14 @vineyard

Enjoy the night vision journey - it’s very cool 😀

And Orion with a certain horsey is now appearing in the early hours. Plus the Rosette which I think is my favourite nebulae - just a fabulous looking thing

Edited October 13, 2021 by GavStar

[PeterW]

Forget focal reducers, eat up the back focus and don’t necessarily deliver the goods. Get a big plossl from Uncle Al and pop the little lens in the top and turbo charge the nebula view! Let Prof Gav be your guide. Put a copy of Brackens Astrophotography Sky Atlas on your Xmas list, but don’t limit yourself to just the hydrogenated stuff… as you have already found!  Go and try stuff out and point it at things and see how you get on… the community has learnt much from people testing out new things to see what happens, what’s visible.

You’re a (cool) white phosphor user… leaves some us “seeing green” 😉

Peter

PS which bit of London are you from, at least Gav and I get to look outwards when we look south!

[Deadlake]

On 12/10/2021 at 18:59, vineyard said:

But NV is visual - the user experience (UX) as techies would say is v much visual.

Nice post on NV. Looks amazing and you have not bought a high end APO.

Ps: I only found this post due to a message, safely buried in the EEVA section where no one will find it…
 

Edited October 14, 2021 by Deadlake

[PeterW]

High end apo… pah, I make do with a truncated 80mm jumbo finder achromat… 

Definitely post positive observations on SGL, it’s a valid way of observing, though it might upset some people… it would make an awesome outreach tool.

Peter

[vineyard]

Thanks for that tip on Brackens @PeterW - Xmas list it is.  I'm S-facing in N London so looking up is about the only way to look out!  And being an inveterate tinkerer I intend to try all sorts of daft things with this NV kit.

Thanks too @Deadlake - yes NV is clearly like the bogeyman & must stay hidden under the bed for fear that it will frighten the pure & innocent😂.  The big problem with that is that it doesn't give a complete picture to lay-readers.  For example, reading the recent reports on the observations of the propeller in M13 w big dobs in dark skies.  Those sound brilliant & I'm v pleased for those folks who were able to do that.  A reader would think that that's whats needed to see the propeller (and ofc if you live in those skies & are able to get a dob that big, then good for you!).  But Gavin and I also saw the M13 propeller with a wee refractor & NV in Bortle 8 London.  An interested lay-reader would never see that in the Observation section, and would have a wholly incomplete picture of what is possible (or what is needed).🤷🏾‍♂️

An analogy that comes to mind is if, for example, a scuba diving board said that folks who use closed-circuit rebreathers were not allowed to report on dives in the same section as open-circuit divers.  I think that would be met w much mirth, & probably even some derision knowing how irreverent fellow divers are.  Kit stuff clearly has to be different, but a dive is a dive is a dive. And folks value reading & learning about how the same dive site can give different experiences with different kit.

Anyway it is what it is - I thankfully missed the mini-civil war that seemed to happen on this & have no desire to go down that back-alley.  I guess other than ghettoised nuggets, there is no other way (verboten!).  CN actually seems much more useful & inclusive on this topic - I have particularly enjoyed reading the experiences  of CN'ers whose expertise on other topics (such as BV'ing) I have found v helpful in the past.  Shows that there are many ways of enjoying this hobby.

Cheers

[Stu]

Nice report @vineyard. Ironically I found your post quite easily just looking at the recent posts feed, so it’s not that hidden.

I’ve had the pleasure of observing through Gavin’s NV kit on a number of occasions, seeing the Horsey from my back garden was quite amazing, and something that was totally unexpected I think for both Gavin and me when we pointed the scope at it. I do agree that the experience is one of observing, more than, say, live stacking etc and it feels a very natural and intuitive thing to do. Complete novices are normally able to view through it very easily which is great for outreach.

NV effectively has its own section on the forum within EEVA, and I do think it is important that members reading reports are clear on what they are reading. We have had examples of observations carried out with NV in large Dobs where NV is not declared and so for new or unaware readers it becomes very confusing as to what is and isn’t possible.

I’m am sure you will love the NV gear, particularly when you get the filters and a faster scope. NV certainly seems to response to focal ratio speed very well, much like imaging I guess. Have fun 👍👍

[Basementboy]

Hi, as another newbie it took me a while to figure out what this post was about. I live in London (also south facing) and it can be a struggle to see much, so was intrigued. Just Googled PVS-14 and it seems it's a monocular night-vision lens costing £2k+, correct? How does it work? Do you strap it to your head and then look through the EP? Plus various filters? 

[PeterW]

Have a look though posts by AlanJGreen and gavstar,l on SGL, should help answer your main questions questions about what and how. You can handhold or put into a scope secondhand around£2-3k, new double that. 
Certainly shows you far more than you have any right to see from the city, also works nicely under darker skies…. You no longer neeed a huge scope, though a fast one really helps.

Happy to answer further queries, London seems to be adding NV users.

peter

[GavStar]

Here is a link to a blog I wrote for Televue which describes how you can use a night vision device for astronomy

https://televue.com/televueopticstalk/2019/02/27/night-vision-in-the-uk-seize-the-night/#.YWhWw6TTUWM

[Highburymark]

Excellent post Vineyard! I’d missed it until now, but better late than never. You nailed it - this is visual astronomy, and it’s transformational. 
I now look at my PVS-14 as two machines - one, to be used with the fastest set up possible with the strongest filters for nebulae, and two, as an add on to normal viewing of globulars, galaxies and open clusters, ignoring speed. As long as transmission is good, even a relatively slow system (F/7.5 refractor, 18.2mm or occasionally 11mm Delite) delivers wonderful views of the brightest dsos like M13. And this is in worse light pollution than Gavin’s. As for night vision under dark skies - it blows you socks off. Dark skies with a large scope? Well, I’ve never experienced that, but Gavin’s images speak for themselves. 

[vineyard]

Thanks @Highburymark - yes that two-machine approach is a great description of exactly what I'm hoping for.  I intend to have the PVS-14 out by the scope alongside other EPs pretty much every sustained session (and then by itself for quick sessions).  The 642nm filter arrived today along with some adapters from RAFCamera.  Just need the clouds to disappear for a bit 🤞🏾

And as for dark skies, I'm managing my expectations down but am secretly v keen to see what this will show.  Its so small & light it will fit into my TV76 carry bag alongside the TV76, a diagonal & a few EPs = exceptionally holiday-friendly way of carrying the equivalent of a much bigger scope 😀

[Highburymark]

46 minutes ago, vineyard said:

Thanks @Highburymark - yes that two-machine approach is a great description of exactly what I'm hoping for.  I intend to have the PVS-14 out by the scope alongside other EPs pretty much every sustained session (and then by itself for quick sessions).  The 642nm filter arrived today along with some adapters from RAFCamera.  Just need the clouds to disappear for a bit 🤞🏾

And as for dark skies, I'm managing my expectations down but am secretly v keen to see what this will show.  Its so small & light it will fit into my TV76 carry bag alongside the TV76, a diagonal & a few EPs = exceptionally holiday-friendly way of carrying the equivalent of a much bigger scope 😀

Absolutely. My travel scope is a TV85, and taking the PVS-14 away is no more difficult than packing an extra eyepiece. I’ve just bought a Baader zoom for the same purpose - nice eyepiece in its own right but can also be used for night vision with an adaptor from Precise Parts. The prospect of zooming in on globular clusters from a dark holiday location is one I’m very much looking forward to.

[vineyard]

13 hours ago, Highburymark said:

...I’ve just bought a Baader zoom for the same purpose - nice eyepiece in its own right but can also be used for night vision with an adaptor from Precise Parts. The prospect of zooming in on globular clusters from a dark holiday location is one I’m very much looking forward to.

 

That's a nice set-up.  Thanks for the tip on the BZ - hadn't heard about that.  Something to add to the research list!  Cheers

[joko]

On 14/10/2021 at 16:47, Basementboy said:

Hi, as another newbie it took me a while to figure out what this post was about. I live in London (also south facing) and it can be a struggle to see much, so was intrigued. Just Googled PVS-14 and it seems it's a monocular night-vision lens costing £2k+, correct? How does it work? Do you strap it to your head and then look through the EP? Plus various filters? 

A NV eyepiece made for astonomy works like any eyepiece, it has a 1.25" barrel so you just plug it in the focuser.

But please note PVS-14 is made for terrestrial use, not for astronomy, so you can't use it in prime (in the focuser) and you can't add SLR/camera lens for handheld use.

Here is a review wrote by GavStar in Astronomy Now magazine this year, it may help you :

https://astronomynow.com/2021/07/29/reviewed-ovni-m-fom-2600-night-vision-eyepiece/

Please note the intensifier tube in the PVS-14 housing has been replaced before the test by an OVNI Night Vision Astronomy grade tube that i supplied. This is something i'm often asked by PVS-14 users. This is not explained but by PVS-14, this is only the housing, 80% of the price and the results obtained with a Night Vision Device is made by the intensifier tube.

Edited October 23, 2021 by joko