275 replies to this topic

[cj7hawk]

Anyone interested?

Yes, I am serious... Some heavy DIY involved and a but of glue and cutting and more glue and cutting, but something with a lot of gain, very low noise and cheap.

More suited to fitting a permanent lens of fairly short magnification ( eg, under 200mm ) and using for locating objects, for which it is excellent, but if you're really dedicated and a glutton for punishment, you could attach it to any telescope.

Now, before anyone gets too excited, there are some caveats.

1. It weighs about 2Kg.
2. It's about the size of a pringles can.
3. It has some serious "fisheye" distortion.
4. It involves older, surplus tubes.
5. You can connect a video camera if you like. Heck, it already weighs 2Kg - you could attach a Betacam if you like.
6. It's a beginner level project. If you can tie your shoelaces but only barely, it's not for you. If you can cut straight, use sharp tools and color within the lines, it should be doable.
7. It involves PVC plastic and black plastic paint.
8. It will look ugly, but it will compare to older Gen3 tube technology even though it's actually Gen1 technology. ( Called "Cascade" or "Multi-stage" or "Starlight" technology.
9. You can make a terrestrial project out of it. They work well down to starlight levels without any extra IR.
10. You will have to find the parts. I can only provide guidance. But I've seen someone make one with duct-tape and cardboard as the main components.

If anyone is interested, let me know. A fun project and great for spotting satellites, meteors, comets, alien motherships or anything else that comes close to the earth but is a little difficult to see.

And before I get too far into it, you can see details of previous projects here: http://aunv.blackice...s&story=cascade

But I will be straight up and say "I have never made one of these for an eyepiece adapter before and it may not be very pretty... But it should work OK."

Anyway, this first post is to gauge interest. If anyone is interested, I'd be happy to make it a group project. It's still fun even as an example to how to make your own kit and you can always buy some cheap Gen2 or Gen3 tubes to make your own eyepiece using the same technology.

Even that probably won't be pretty, but if you're in for the ride, let me know I've run projects like this on a few forums in the past and they go down pretty well, though most of the people who use them with telescopes are spotting satellites or aircraft or other flying objects.

But if the interest is eyepieces and the weight doesn't make you burst out in laughter, I'll go through the motions there too and talk you through everything you wanted to know.

The fun comes with a lesson in how intensifiers work and everyone is welcome to watch who doesn't join in. Just so it's known upfront, I don't get anything out of this except enjoyment - so I don't sell the parts or make any component of it.

Regards
David

[cj7hawk]

Oh yeah, I should add, although it's military technology for the project, it's export-compliant so it's an international project, well, mostly anyway. Not just US based.

Regards
David.

[ccs_hello]

David,
Nice work! I think this Gen 1 P8079 cascade tube (3 stages) datasheet can be helpful:
https://picasaweb.go...CNix_PfG9sHCqAE

Clear Skies!

ccs_hello

[nytecam]

A fun project - I've played with Gen#1 EODs in the past both single stage, single stage with polarity reversed [Ov at output screen for contact photo-film] and triple stack EOD and as you say the latter is heavy. Mine used exclusively for astro and were all quite noisy. Used M42/Pentax screw adapter to receive s/h camera lenses from 28mm to 300mm. Currently use a cheap commercial NVD but good luck with your project

[Dragon Man]

David, if you gain interest in this thread from folks wanting to build the project, go ahead and do a tutorial.
Don't tack it on the end of this one though. Make a whole new thread entitled 'DIY Intensified IIT setup for around $200 project - Tutorial' and I will add it to the other tutorial threads so it won't get lost

[cj7hawk]

Thanks Ken -

LOL, I should have thought of that, that in an electronics forum section in which everyone probably knows how to assembled a telescope that most of you would know how to add an IIT already.

An easy enough mistake to make as the new guy Kind of embarrasing too. I saw a few projects here, but not DIY IIT systems. I guess the experience level here is higher than I thought.

If the knowledge around here is at that level, I may not find anyone new to the concept, but if anyone is interested, I will do that then

Out of interest, have many on this forum already made their own eyepiece?

Regards
David

[Dragon Man]

David, there aren't as many as you think that know about IIT's.

I for one know absolutely nothing about them except they give a green image
But if you do get interest, I'll add your Tutorial

[cnoct]

David, Really good idea and I look forward to seeing you do this. I would like to make some suggestions. It is certainly not be a $200 dollar one but may be of interest to some.

Here are my suggestions:

A guide on the types of image intensifiers most easily adapted for telescope use and ones that are currently available from ITT, L-3, Photonis etc… These would probably be more or less limited to the MX-10160, MX-10130 type and possibly the MX-11769. This list could include companies located outside the U.S. so as to not leave out those that are not able to purchase from the U.S.

A list of suppliers where these image intensifier tubes can be purchased:

http://www.summitnig...mage_tubes.html
http://www.nvdepot.c...fiers/index.asp

A list of OEM housings that can easily adapted such as the AN/PVS-B/D and Micro monocular and are available with or without the image intensifier. Also units such as the, AN/PVS-7A/C, B.E. Meyers OWL and Recon M3NV (formerly Star-Tron MK-880) etc... This list would be pretty long and a bit involved as some units already come with suitable lens mounts e.g. c-mount while others need simple adapters made or purchased. I’d probably limit it to the ones that are the simplest to adapt since anything with an image intensifier can be adapted to a telescope, A good example would be the AN/PVS-7B/D, which is cheaply available second hand. These units are fantastic for astronomy and only require the purchase of a c-mount adapter that replaces the objective lens. These adapters can be sourced from places such as:

http://www.adamsindustries.com/

Video or text on how image intensifiers work such as the following:

http://www.youtube.c...h?v=gpwSnb_mgkM
http://www.youtube.c...feature=related
http://www.nivitech....tvision-gns.htm

A guide to performance specifications and what they mean in the real world. As well as which ones are more crucial than others and why they are so.

A realistic guide on the limitations and benefits of image intensifiers for general star gazing and telescope use. This could include the type of telescopes most suited to image intensifiers.

I am sure there are a few suggestions missing but it’s as start. No pressure , just some thoughts that might enable more folks to enjoy image intensifiers and realize that they are accessible and easily integrated into telescope use. This is not to mention their unmatched use as a general stargazing tool.

[efahrenholz]

David, I have kinda wanted to try this in the past, but the weight was just a massive hurdle to overcome. The problem is the mounting points. You need to be able to anchor the intensifier to the telescope (excluding a reflector possibly) in a fashion that allows easy removal. I thought about it, but everything I came up with involves permanent mounting to a telescope.

You could utilize a lightweight housing for the intensifier, or I suppose PVC would work but it is a bit heavy. Most telescopes offer t-mounting and I recommend trying to mount it that way. A 35mm slr bayonet mount would be best, as c-mount is a bit narrow but could work. There needs to be sliding rails that we can pinch down because a focuser will not hold the intensifier, it will just roll out. I thought about using those rails off of desk drawers but adding a threaded stop screw (like the ones from eyepiece holders) or you could bend in the rails so it doesn't slide unless you overcome the pressure. Honestly, the focus knob is going to take some imagination. I'll brainstorm a bit but the very best idea I came up with is a threaded stop screw against some moving part.

[PEterW]

More details on how this would compare to a reasonable gen3 tube.... Gen1 are usually not worth the bother! How well would it couple to a fast scope? Can you provide some data on the tube response, I'd be interested to see what kind on h-alpha response it has... To hunt down sharp less emission nebulae. I am tempted by the price and the use of epoxy and duct tape.

Cheers

PEterW

[Lightning]

Very interested, though it better be international. Being stuck with Gen1 in any country other than US is such a load of bull...

[cj7hawk]

Hi Guys, Sorry for the late get-back... A few busy weeks at work lately.

A cascade tube is technically a Gen1, but it uses three tubes in a row to amplify each stage, so it's like a Gen1 to the power of 3. That's an oversimplification of the formula, but it's easier to think of that way. While a normal Gen1 ( or Gen1+ though very few tubes are ) can achieve up to 500x gain, a cascade uses additional stages to get additional gain. These are military tubes as were used in Vietnam and even by the UK forces in the Falklands conflict.

Cascades compare *very* well to Gen3 and are about the same quality as earlier Gen3. They don't convert photons to electrons quite as efficiently ( About 25% of the performance of a Gen3 ) but they are extremely low noise and very high gain - A typical Gen3 has a maximum gain of around 50,000 while a top-quality cascade tube can achieve around 100,000 gain with much lower ebi and noise levels. So in terms of raw amplification, it's about 8x higher gain than a Gen3.

The very best tubes, BTW, are Gen3+1 which are quite rare and also known as hybrid tubes and these couple a Gen3 with low gain to a Gen1 amplification stage. These are capable of visualising individual photons but are best known for low-noise high-gain output. Mostly they use them for military purposes but they cost a lot so are very rare.

OK, thinking this one through, I am going to split the project to cover US and Non-US users. I am going to make it generic, will discuss tube technology in detail, including looking at how to make this project work with Gen1 cascade as well as Gen2 fiber plate and Gen2/3 glass input tubes. I will also extend the project to making standalone scopes with Gen1 cascade and similar and also look at the smaller, lighter 18mm Gen1 cascade tubes, which are sometimes a little more advanced, a lot lighter and might be supportable by a telescope as an eyepiece.

That way, people will be able to assemble either a standalone telescope, adaptable eyepiece or dedicated eyepiece with whatever tubes they can get their hands on. I'll also track down a few suppliers around the world for Gen1 cascade technology.

Lightning - I might even be tempted to make some low-cost Gen3 Omni IV military surplus tubes available for Australian projects if anyone locally is wanting to make one since they are near impossible to import from the US but I only have a few here in Perth and they would be strictly for Australians due to legal requirements.

I'll also look at ways to add a video camera for recording of images. Any other requests, add them in to this thread and if they are in line with the other project objectives, I'll add them in Give me a few days to collect all the parts and order the project components for both Gen1, 2 & 3 and I'll start putting the first part of the project together.

Regards
David

[greg]

Great..... I'll follow this tread....
Thanks for taking the time to share with us.

GregW

[efahrenholz]

David, the best route for adding video to the unit is going to be something lightweight. I recommend a webcam but not any webcam--and spc-900 philips. They will work for video capture and can be modified for long exposures. Another suggestion is the panasonic scb-2000, because it has up to 8 second intengrations. That would make the mallincam croud a little jealous since you could capture objects MUCH quicker. Not as colorful but hey, it's nearly instant fir most deepsky objects.

[Dragon Man]

efahrenholz says:

David, . . . Another suggestion is the panasonic scb-2000, because it has up to 8 second intengrations. That would make the mallincam croud a little jealous since you could capture objects MUCH quicker. Not as colorful but hey, it's nearly instant fir most deepsky objects.

1. It's a Samsung, not a Panasonic

2. The Philips ToUcam 840 Pro II and the SPC900NC are both fantastic webcams. But no-one has worked out how to do a Live broadcast thru NSN with one modified for long Exposure yet.

3. No, the Mallincam crowd don't get jealous of the Samsungs '8 seconds' capture
I use both the Samsung SCC-A2333 and the Mallincam Xtreme together switching betweeen the two and they really are chalk and cheese

But Bang for Buck the Samsungs do a good job.
But Jealous? Not on your Nelly

[cj7hawk]

LOL! I am doing this on the cheap... Actually, my budget for the necessary starting parts has run dry before I got started thanks to a BIG mistake by a company that charged me several thousand dollars too much by accident and now I am waiting to get the charge returned ( They are OK about it and acknowledge the mistake ) - But it's really messed with me ordering some of the extra parts I need.

Anyway, yeah, expect ultra-cheap stuff... And very unconventional, with PC based control of the camera and adjustable high-resolution exposure tubes - but I still need to get and test the camera first.

So far, the equipment list for this project that I have collected and prepared;

1 x P8079HP Cascade Tube ( Gen1 )
1 x xx1130 distortion-corrected 18mm lightweight cascade tube ( Gen1 )
1 x Omni IV level Litton M869 Gen3 tube. Similar to MX10130 in size.
1 x MX10160A style tube. ( or MX11769 )
1 x xx2500 ( MX9644 style ) adjustable gain Gen2.
1 x Gen2+1 "Hybrid" tube...
Assorted C-mount adapters and mount parts.
Battery boxes ( commercial ) and switches and stuff.

So I am planning a Gen1/2/3 project with sufficient information to use whatever tubes the user can get and I'll explain the photocathodes as well. I'll write up a technology primer too.

As for cameras? Think small, like Microscope... Setup like an adjustable focus relay lens. But I need to find the right one.

eg, http://www.ebay.com....e#ht_4005wt_905

It's a 2.0 MP ( 1600x1200 ) image sensor with USB interface and direct-to-PC attachment with software and exposure times out to 1 second and it's very lightweight. With modification, it looks like it might be perfect for what I'm planning. ( Feedback is OK - Image Intensifiers I know, the needs of the astronomy community, I do not )

I still need to buy it yet and determine it's suitability... Also I need to make whatever I do make usable both with eyepieces and camera.

Regards
David,

[earthman]

I have been useing a Dino-lite digital microscope with my ETX-125. Got Jupiter a weekago for the first time. It isnt to bad but it was not a great night out, maybe a 5. I'm going out here in a bit and try out the Dino-lite and a Logitech quickcam i tore up and put a heatsink on. Havnt tryed the webcam yet, thats tonight. lol

What i found out is that focus takes for ever to get just right. Since the microscope focus's too. Once you got it, it works good.

[efahrenholz]

LOL! I am doing this on the cheap... Actually, my budget for the necessary starting parts has run dry before I got started thanks to a BIG mistake by a company that charged me several thousand dollars too much by accident and now I am waiting to get the charge returned ( They are OK about it and acknowledge the mistake ) - But it's really messed with me ordering some of the extra parts I need.

Anyway, yeah, expect ultra-cheap stuff... And very unconventional, with PC based control of the camera and adjustable high-resolution exposure tubes - but I still need to get and test the camera first.

So far, the equipment list for this project that I have collected and prepared;

1 x P8079HP Cascade Tube ( Gen1 )
1 x xx1130 distortion-corrected 18mm lightweight cascade tube ( Gen1 )
1 x Omni IV level Litton M869 Gen3 tube. Similar to MX10130 in size.
1 x MX10160A style tube. ( or MX11769 )
1 x xx2500 ( MX9644 style ) adjustable gain Gen2.
1 x Gen2+1 "Hybrid" tube...
Assorted C-mount adapters and mount parts.
Battery boxes ( commercial ) and switches and stuff.

So I am planning a Gen1/2/3 project with sufficient information to use whatever tubes the user can get and I'll explain the photocathodes as well. I'll write up a technology primer too.

As for cameras? Think small, like Microscope... Setup like an adjustable focus relay lens. But I need to find the right one.

eg, http://www.ebay.com....e#ht_4005wt_905

It's a 2.0 MP ( 1600x1200 ) image sensor with USB interface and direct-to-PC attachment with software and exposure times out to 1 second and it's very lightweight. With modification, it looks like it might be perfect for what I'm planning. ( Feedback is OK - Image Intensifiers I know, the needs of the astronomy community, I do not )

I still need to buy it yet and determine it's suitability... Also I need to make whatever I do make usable both with eyepieces and camera.

Regards
David,

David, have you proceeded with this project? I have ordered one of those 20x-200x usb microscopes. I am hoping that the 1 second exposure time is enough to capture plenty of photons off the phosphor to make a usable image of faint objects. Plus, I can hang out inside while I surf the sky. I hope that this gives me the ability to grab 1 second integration video so I can stack and clean up the signal. This way I can get more details. I figure a second of capture time should help, right?

[efahrenholz]

efahrenholz says:

David, . . . Another suggestion is the panasonic scb-2000, because it has up to 8 second intengrations. That would make the mallincam croud a little jealous since you could capture objects MUCH quicker. Not as colorful but hey, it's nearly instant fir most deepsky objects.

1. It's a Samsung, not a Panasonic

2. The Philips ToUcam 840 Pro II and the SPC900NC are both fantastic webcams. But no-one has worked out how to do a Live broadcast thru NSN with one modified for long Exposure yet.

3. No, the Mallincam crowd don't get jealous of the Samsungs '8 seconds' capture
I use both the Samsung SCC-A2333 and the Mallincam Xtreme together switching betweeen the two and they really are chalk and cheese

But Bang for Buck the Samsungs do a good job.
But Jealous? Not on your Nelly

The intended message is that the aid of an intensifier with an integrating camera will deliver scenes faster than a mallincam. Image intensifiers can deliver instantly what a camera would take 15-20 seconds to capture. While this can be of benefit, occasionally there aren't enough photons to make a complete image in real time. This is where exposing for an extended period of time beats intensifier technology. Combining the two will enable the observer to grab magnitude 10 objects in only seconds instead of one-minute plus integrations. There is a loss of dynamics, because color information isn't recorded. This can be overcome with a filter wheel but it can complicate the process. It's much simpler to realize the luminance data and appreciate being able to see the object quickly.

It's also a lot more cost prohibitive to purchase a mallincam, as you can pick up a decent cascade tube and samsung camera for under $500. Putting a housing together is simple, as it's really just dremel and pvc work. I hope this clears things up.

[runner70]

I am currently trying to adapt my p8079hp for astronomy viewing. I have encased it in pvc tubing and will employ a separate mount to mate it to my f/4 sn 10". Has anyone combined this nv tube with a telescope, and with what results? I am to test it tonight with a ~10nm h alpha filter. Any suggestions?

[Furmo]

I used parts from an eyepiece projection photography adapter I never got around to using - it basically allows me to screw my cascade tube directly onto the 2" focuser of my Startravel 120 f5 refractor. This means I can easily switch from NV to normal observing and my telescope didn't need any adaptation at all.

I also fashioned an eyepiece holder to the rear and rearranged the elements in a cheap eyepiece I had so I can use that rather than needing a camera, or looking at the little rear screen from a distance.

I can upload photos of it tonight if you like but my efforts are very 'industrial' to say the least - lots of poor soldering, zip ties and duct tape! I also have another tube with a camera lens attached for hand-held viewing - neither look very pretty but they both work well.

[runner70]

Which tube are you using, and what are your results?

[mattflastro]

I am currently trying to adapt my p8079hp for astronomy viewing. I have encased it in pvc tubing and will employ a separate mount to mate it to my f/4 sn 10". Has anyone combined this nv tube with a telescope, and with what results? I am to test it tonight with a ~10nm h alpha filter. Any suggestions?

Where do you get these tubes in the USA?

[seryddwr]

The only place I've seen the Gen I cascade tube is here at 80GBP (about $123 US, plus $7 for international shipping) it's tempting. I've had my eye on one of these, but they cost quite a bit more.

[PEterW]

Anchor supplies in the UK a bit cheaper but more on postage.... Only sources I know in the world.... Get them while there is still stock left.

Peter