Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

DIY Gen 1 Cascade P7089HP cruise ship NVD

  • Please log in to reply
63 replies to this topic

#51 nimitz69

nimitz69

    Mercury-Atlas

  • *****
  • topic starter
  • Posts: 2,819
  • Joined: 21 Apr 2017
  • Loc: A barrier island 18 miles south of Cocoa Beach

Posted 02 September 2020 - 05:28 PM

I’ve been told the Cascade tubes are powerful enough (gain of 100,000) that using something
Like my 7nm Ha is no problem. Don’t know about something like a 3nm but I don’t have one of those for my NV

#52 nimitz69

nimitz69

    Mercury-Atlas

  • *****
  • topic starter
  • Posts: 2,819
  • Joined: 21 Apr 2017
  • Loc: A barrier island 18 miles south of Cocoa Beach

Posted 02 September 2020 - 08:56 PM

So it was clear tonight enabling me to do a side by side comparison of my MOD3 and my Cascade Gen 1 systems.

I used my Fujinon 50mm f/1.4 lens for the comparison.

No big surprise that the MOD3 gave better views overall but the Cascade NVD was surprising good. The PVS-2 does suffer from a fish eye effect at the edges but the center of the image is bright and distortion free. When just looking at random star fields the Cascade showed pretty much the same stars as the MOD 3 as far as magnitude. I picked out some easily identifiable faint star fields and when looking through the Cascade NV I could see the exact same fields.

Using the 640nm LP filter gives better views on the MoD 3 then without but on the Cascade the view was actually quite a bit better without a filter. I then put on my 7nm Ha filter on the Cascade to see if I could find any nebula. I went to look for the NA nebula since that should be the easiest for me to locate. Although there was a lot of ‘noise’ in the image I could still make out the nebula. I then switched to the Mod 3 and while the image was cleaner so the nebula stood out more it was not exactly a ‘night and day’ difference.

So the good news is that the Ha filter works but I’m wondering if a 12nm filter might be better for the Cascade NV? Not sure I want to spend the money to find out jus yet so I need to ask around to see if anyone has one I could borrow to see if it makes a difference.

Edited by nimitz69, 02 September 2020 - 09:00 PM.

  • GeezerGazer and Hilbily like this

#53 nimitz69

nimitz69

    Mercury-Atlas

  • *****
  • topic starter
  • Posts: 2,819
  • Joined: 21 Apr 2017
  • Loc: A barrier island 18 miles south of Cocoa Beach

Posted 17 September 2020 - 12:36 PM

I was asked to put a project summary up in case anyone wanted to build one of these so here it is:

 

As built in this thread: $431.58

Material list:

P8079HP Cascade tube:  Ebay

PVS-2 housing: ebay

PVS-2 ocular & battery caps: What-A-Country

6v battery compartment w/wires: Amazon

Toggle switch: Amazon

Ring terminal wire connector/heat shrink tubing/metric bolts: Ace H/W

Objective lens front cap:   3" PVC cap @ Ace H/W

Female C-mount adapter/threaded lock ring/5mm extension rings: Amazon or any astronomy store

 

Tools:

Soldering iron

RotorTool w/metal cutting blade

Chop saw

Drill

Screw drivers/wire strippers/crimpers

 

There are 2 other options to build one of these:

1.  StarlightNV (UK company w/online store) sells a complete DIY kit.  all the parts have been machined & fit together so all you's need to do is buy a tube (which they also sell), wire the tube up & screw everything together.  this is the simplest, turn-key DIY option - no thinking required but it will cost you:

$846.54 (incls tube) + shipping to U.S.)

2.  the other option is to use a simple aluminum 3" dia tube instead of sourcing a PVS-2 housing.  This requires the most "work" as you'll have to to a bit of trial & error to get the spacing correct between the tube/ocular/objective lens to ensure it will come to focus but its also by far the cheapest method:

~ $360

 

I will try to get a few cell phone pics of the 2 NVDs side by side so you can see what you'll see as compared to a Gen 3 WP manual gain MOD3C as soon as the weather clears


Edited by nimitz69, 17 September 2020 - 12:50 PM.

  • GeezerGazer likes this

#54 GeezerGazer

GeezerGazer

    Apollo

  • *****
  • Posts: 1,387
  • Joined: 06 Jan 2005
  • Loc: Modesto, CA

Posted 17 September 2020 - 05:51 PM

A great project!  Thanks for sharing. 

Ray



#55 Oukifrench

Oukifrench

    Explorer 1

  • -----
  • Posts: 68
  • Joined: 19 Feb 2018
  • Loc: France Perpignan

Posted 01 October 2020 - 05:51 AM

Thank you very much for this post, i also use an 8079 hp in france, i was a little ashamed to post but it makes me want again.

But it's not really easy to develop around this gen1.

Do you think with your experience experience that it is possible to put it on a telescope? I plan to use it on a celestron c5 with focal reducer at F3.

friendly ouki

 

With Google translator


  • Joko likes this

#56 nimitz69

nimitz69

    Mercury-Atlas

  • *****
  • topic starter
  • Posts: 2,819
  • Joined: 21 Apr 2017
  • Loc: A barrier island 18 miles south of Cocoa Beach

Posted 01 October 2020 - 11:02 AM

Someone asked me that exact same question at my club when i gave my presentation on how to do it. Since it has female C-mount threads on the objective front you could easily screw on a C-mount to 1.25” or 2” adapter to fit into your telescope but its pretty long 12” and still heavy ~ 4 lbs. Functionally it will work but you probably want to be very careful using it.

Depending on how you made your DIY scope = threaded parts, glued together or force fit it could be stable. For me, my front objective cover is just a force fit so it would never stand up to the torque if I tried sticking it on to a telescope ... the front cap would likely just pop off ...

#57 Oukifrench

Oukifrench

    Explorer 1

  • -----
  • Posts: 68
  • Joined: 19 Feb 2018
  • Loc: France Perpignan

Posted 02 October 2020 - 03:42 AM

OK thank 's la lot waytogo.gif



#58 nimitz69

nimitz69

    Mercury-Atlas

  • *****
  • topic starter
  • Posts: 2,819
  • Joined: 21 Apr 2017
  • Loc: A barrier island 18 miles south of Cocoa Beach

Posted 02 October 2020 - 07:10 AM

Can you post a pic of your DIY NVD?

Edited by nimitz69, 02 October 2020 - 07:10 AM.


#59 Oukifrench

Oukifrench

    Explorer 1

  • -----
  • Posts: 68
  • Joined: 19 Feb 2018
  • Loc: France Perpignan

Posted 02 October 2020 - 07:28 AM

2020 10 02 14 16 53 746
Album: scopes Eaa
1 images
0 comments

 
Low cost astro night vision p 8079hp

Here is my modest multi compatible night vision system finally finished.
Compatible with 1.25 "2" M42 T2 c / cs sinking
Brief photo lenses, exotic optics and virtually any telescope.

Here dobsonian mounting on its graduated table with as optic a c5 with variable reduction gear (meade 3.3 but with variable extension therefore variable reduction)

In demo version, images directly on the tablet because not usable visually in this configuration but easily posable on an equatorial or az mount and there ok for visual.

Tests to come but moon and clouds are in the game at the moment .........

If successful transfer to the c8 

Ouki

 



#60 nimitz69

nimitz69

    Mercury-Atlas

  • *****
  • topic starter
  • Posts: 2,819
  • Joined: 21 Apr 2017
  • Loc: A barrier island 18 miles south of Cocoa Beach

Posted 02 October 2020 - 10:07 AM

Nice, quite a bit more sophisticated then my simple scope

#61 VegaSkyLoom

VegaSkyLoom

    Lift Off

  • -----
  • Posts: 5
  • Joined: 03 Jun 2021

Posted 07 June 2021 - 10:05 PM

Restarting this great discussion ... and I'm wondering if anyone can advise on whether any image whatsoever can be discerned from just the P8079 tube? I'm using the non-HP variant.

 

Ive not yet placed the 35mm lens on it. Is it possible to see any detail whatsoever from the output of the tube alone?

 

I'm concerned as all Ive got is what looks like a completely washed out green field. No detail at all.

 

Anyone have a non-HP variant user manual?

 

I apologize that Ive also previously started a topic on this issue. I wouldve started here if I had seen this, but Im just trying to reach out to the users in this particular forum at this point. Shout out to Dale E who tipped me off that a lack of detail might be par for the course.

 

Ive accesed the gain control beneath the rubber, and when I adjust it just makes the solid green image brighter or dimmer. No detail on trees or stars etc. Is the lens required to see anything whatsoever? I just want to make sure this is still a good tube.


Edited by VegaSkyLoom, 07 June 2021 - 10:14 PM.


#62 nimitz69

nimitz69

    Mercury-Atlas

  • *****
  • topic starter
  • Posts: 2,819
  • Joined: 21 Apr 2017
  • Loc: A barrier island 18 miles south of Cocoa Beach

Posted 02 July 2021 - 05:38 PM

you will not be able to see an image through just the tube, you must focus the light by using some combination of eyepiece and objective lens. It would be like looking through the viewfinder of a DSLR without a lens attached (well sort of).

 

all these tunes that are made into NVDs are in a housing with a n objective lens at one end and some sort of eyepiece at the other end ...



#63 careysub

careysub

    Mercury-Atlas

  • *****
  • Posts: 2,650
  • Joined: 18 Feb 2011
  • Loc: Rancho Cucamonga, CA

Posted 03 August 2021 - 04:20 PM

Ok, thx. When i wired it up to test the tube there was no issue but when I was chatting with a guy who refurbs PVS-2s, makes a new 6v battery compartment & then sells them he talked about the “capacitor” which got me wondering ....

 

The AN/PVS-2 I have is (judging from my copy of TM 11-5855-203-23) a AN/PVS-2 or AN/PVS-2A which as an external oscillator, which is probably the "capacitor" he is talking about. It converts the input battery voltage to high voltage for the tube. The AN/PVS2B uses a tube that has the high voltage source built into it. In the AN/PVS2B the oscillator is replace by the ABC adapter, which I gather just passes through the 6V current.

 

This component on my system is shown below. I think that must be an ABC adapter as it does not look like much like a functional electronic component.

Attached Thumbnails

  • IMG-3121_sm.JPG


#64 careysub

careysub

    Mercury-Atlas

  • *****
  • Posts: 2,650
  • Joined: 18 Feb 2011
  • Loc: Rancho Cucamonga, CA

Posted 03 August 2021 - 04:37 PM


 

here's the spacer and you can see the 2mm sliver ridge once assembled

attachicon.gifspacer.jpg

attachicon.gif5mm spacer.jpg

 

NVD with all the pieces assembled.  Unit is now 3lbs 14 oz vice the 6 lbs 4 oz of the Starlight AN/PVS-2. and with the objective lens removed it is only 11" long vice 15"

attachicon.gifcomplete.jpg

 

remaining steps: wire the switch & battery compartment together, solder neg battery lead to tube, mount a plate to the bottom of the unit (there are 2 threaded holes) and drill a hole to attach my photography tripod mount plate.  And finally test to ensure I can reach infinity focus ...

You have inspired me to modify my AN/PVS2 to make it suitable for astronomy rather than start with a from-scratch build.

 

One reason I wanted to ditch my original housing was the weapon mount that was attached to it by frozen screws. I finally got the mount off by hacksawing through it as it was thankfully made of aluminum) but by itself it weight 400 g, almost a pound of pure dead weight that also made setting up an astronomy mount for it impossible.

 

I started a thread a couple of months ago about the fact that I could not get point stars with this, just rings and in investigating it, taking the lens off, I found that it seemed to a catadioptric lens by its construction, except that what should be the central mirror was black on the inside surface. Whether it is really catadioptric (I would think it would not work at all if that were the case), the weird central obstruction made it useless to me, so cutting down the front to install a C-lens mount would be a big improvement in size and weight if I use a lighter fixed lens (the original lens is 462 g).
 


Edited by careysub, 03 August 2021 - 04:38 PM.



CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics