Post by davy.... Shirva.. on Jul 3, 2019 18:40:19 GMT
A quick recap,, since all this can be a bit confusing. Project was to build a night vision telescope,, type of thingy. Von can name it lol.
So I got a night vision cascade tube from eBay about £102 delivered,,, thought I got it at a good price hence give it a go. Had a CCTV lens in my analogue Astronomy gear and a c to cs adapter.
I 3d printed a front cap for the lens to be mounted on , then the cap fits on cascade tube,, this was my third attempt,, The end cap must let the CCTV lens get as close as possible to the CCTV lens.
Rear cap made this to hold 2" Astronomy focal tube or 2" to 1.25" adapter,, this was to save multiple printing. Printing the caps was 2.5 to 3 hours each.
The viewing end I used a 36mm, 30x magnification jeweler's loop, it needs to be as close as possible to the cascade tube lens as well,, I printed an adapter to hold it in place.
I then bought a 300mm dovetail, mounted canon 4000d with standard lens on it. Measured up and printed a new body that aligned the DSLR lens to the NV, I made shure that the DSLR lens can go inside and have plenty of movement,, focus ect.
Fitted all together and looking great.. Canon lens has to be on manual focus,, looking good, Next up new battery box to print.. Looks like it's a successful project..
Post by vondragonnoggin on Jul 4, 2019 1:32:53 GMT
I’m getting excited to see some pictures from it!
If you have a cctv lens on the input side of the tube with F/1.2 - F/1.4 type speed, you should be able to get some bright wide view shots with your dslr.
Is your narrowband Ha filter a 1.25” filter or 2” filter? Hopefully you can mount it in front of the cctv lens easy.
The other filter that will be effective is a longpass filter that still allows some Ha through. Some of the guys over at CN have discovered that an Astronomik brand UHC filter works well as a 640nm longpass filter. It’s nearly identical to the Lumicon Night Sky H-Alpha filter curves with the addition of the Astronomik having the two OIII lines and one Hb line still visible.
A nice discovery for people wanting to get the most out of one filter with visual nebulae viewing, NV longpass viewing 640nm and up, or narrowband camera work in the OIII and Hb range while still having Ha broadband available. The NV tube won’t pick up the OIII and Hb lines anyway.
I was successful the other night in bringing my Startravel 150 to F/1.4
Most amazing live narrowband Ha views I’ve ever had. Only 7.7x mag so image scale was small, but every bit as bright and quite a bit larger image scale than my 75mm F/1.4 cctv lens with 3nm Ha filter over the front of it. The combination of afocal setup and use of two 35mm extensions between my reducer and the afocal eyepiece base brought reduction to 0.28x
So basically turned my 150/750 scope into a 150/210 scope. A whole lot to be seen this time of year near Galactic center (Lagoon, Trifid, Eagle, Omega, Cats Paw, War and Peace, etc) and near Vega and Gamma Cygni area. (North American, Pelican, Crescent, Gamma Cygni, Elephant Trunk, Veil, Dumbbell, etc). A lot of very large nebulae that should show up in the p8079hp using a narrowband Ha. Longpass is amazing for clusters and dense starfields like Sagittarius Star Cloud. Should be a lot a smaller cctv lens can bring in with very wide views with an Ha filter in front of it.
Glad it’s turned out to be successful! Maybe we can get others to use intensifiers over on your side of the pond. You’ve joined the ranks of the small handful over there doing NV Astronomy. I think one of the SGL members mentioned only about 7 people in the U.K. using intensifiers for astronomy.
Hi Von The lens is a computar 50mm 1:1.8 hopefully still do a job,, will look out for a bigger faster lens when finished battery box
That should be nice for some wide bright views. Hopefully you can fit an Ha filter over the front of it to try some narrowband!
I use a 50mm 1:1.8 with a 2” Ha filter over the front. You can take in Barnards Loop, Orion, flame, Horsehead all at the same time in the winter.
Summer Galactic center will be full of nebulae you’ll catch with that size lens. I use a 49mm to 48mm stepdown ring to fit the 48mm filter threads on the 50mm lens. It gives about 2x power with that lens. I think my 75mm 1:1.4 is a Computar lens. My 50mm is a canon EF I use an EF to c-mount Adapter for.
The Nikon F to c-mount adapter and the Canon EF to c-mount adapters both have enough space between c-mount and lens mount to glue a 1.25” filter ring in so you could use 1.25” filters behind the lens and before the input window of the intensifier tube if you went with a Nikon F mount lens or Canon EF lens. A little bit of filter effectiveness rolloff from bandwidth shift at those speeds around the edges, but in the case of the p8079hp tube it shouldn’t matter because the tube itself has some fisheye effect near the edges. Center FOV should be great though. Once the filter ring is epoxied or glued in place, getting the little 1.25” filters to start threading is a little fiddly, but works good once that first thread catches. There are adapters for just about every type lens to c-mount and all but the M48 to c-mount have enough space to glue in a filter ring to screw in 1.25” filters. The M48 to c-mount doesn’t have any room between lens and adapter c-mount side. All others I tried were ok.
Its kind of a tradeoff for easy to use 2” in front, but some slight vignetting or fiddly thread start if using a 1.25” filter in the lens adapter. The 48mm filters have about 45mm clear aperture so slight vignetting with a 50mm lens. But again, edges not so important.
Well done davy. You are certainly becoming an expert at this 3D stuff
__________________________________________ Ken James - Snake Valley Australia CAMERAS: Samsung SCB-4000, Mallincam Xtreme & Xterminator, 3 different Revolution Imagers, 2 ToUcams, SX-5c, Canon 350d, 2 different IMX224's (an RI & RT) and an RT178. Broadcaster on NSN as 'Snake Valley Australia' HERE --> www.nightskiesnetwork.com/ - Video Astronomy Website: ballaratman.wix.com/videoastronomy
Post by davy.... Shirva.. on Jul 5, 2019 14:36:42 GMT
Doing the 3d printing a digital Vernier guage is a must,, and design spark mechanical software is really good for doing parts. Really enjoying doing the night vision project,, think I've put my own mark on doing it,, have more to do on stage two.. fitting a laser pen to it .. Just need pass marks once I try imaging with it,, With the DSLR attached I can use backyard Eos and see how it fairs
Post by davy.... Shirva.. on Jul 6, 2019 6:20:46 GMT
On the new main bracket I made two 5mm holes in the design, this was to have parts mounted,, I cut a 5mm bolt to use as a pin to hold the battery box holder secure with epoxy glue as well
Worked well,, battery box holder held solid.
What didn't work was the 3 volts to power the NV,, it definitely needs 6 volts, was a bit annoyed at this as the battery box I bought had a small footprint and a built in switch,, Found solution, the battery box holds two aa batteries to create 3 volts,, I removed the positive plate and if I 3d print a spacer block I can reduce the size of the aa space down to make the small 6 volts battery fit,, epoxy glue it in place and glue the positive lead to it,, Job solved
Post by davy.... Shirva.. on Jul 6, 2019 21:38:53 GMT
3d printed a rectangle box and epoxy glued into position,, glued the positive lead to the box,, the small 6volt battery sits in perfect, I made a second rectangle box and glued it in where the second AA battery would go, this is spare battery holder. Just need to solder wires and heat shrink cables,, got hairy joints just now wrapped in tape, till I get heat shrink from work
well it never quite went to plan last night,,,no stars out that I could see naked eyed,, put the nv on the heq5 and fired off some shots.. pretty disappointed ..have bus garage 1/4 mile max from me and could not focus,,clouds could be made out in another shot but no stars ect, took a photo inside flat of my dvd collection and it showed some promise...back to the drawing board.
I THINK THE PROBLEM IS THE LENS,, I cant adjust it enough to the right when im trying to get focus
took the camera off, and the image just looking through the 30x mag loop is fantastic...what an image ..trying not to burn out the tube,,but I need input to sort problem out.. the dslr lens was at 18mm and felt i had to come back further ,,at 55mm on the dslr lens it was crap. the switch to the fd lens on the cell has been a good move.. if I can get the view on a camera that I can see just through jewlers loop,,id be delighted
Post by davy.... Shirva.. on Jul 7, 2019 22:28:35 GMT
Bit of testing now it's dark,, I've found that to get decent focus,, it's a three step operation. I'm using the canon FD zoom lens.
Stripped the back end off and used three Different magnification jewlers loops,, up against the cell rear lens,, I then moved the loop further back away from the eyepiece , I get great focus
So here how it works,, set aperture to get the brightness you require,, then I will need to adjust focal length of jewlers loop till I get focus then set the zoom and fine tune the loop again,,, No idea how the DSLR will work,, at A focal ,, but getting sharp focus is first problem
Post by davy.... Shirva.. on Jul 8, 2019 7:24:01 GMT
Cheers Von Still going to make a new back end with a focuser to move the jewlers loop,, don't think it has to move much, but needs to be adjustable. Thinking along the lines of a rear end that will hold a tube with the jewlers loop on the end and be like a clamp type rather than a bolt pushed against the focal tube.