NBTV Camera Question

[Harry Dalek]

Here are a 1.5 turn and single spiral dxf file at CD size in DXF format:

Thank you for that Gary ! thats great ,see if i can print those out right size the + makes life easier as well the dots on print outs are so hard to see on some of the other nipkows i have seen .

[Harry Dalek]

Today i had a go at the Nipkow i made a 32 and and one and half spiral garys ...dxf files

I made them with a needle in the Dremel tool the friction works its very easy to make the holes...the first two disks are just test ones i want to see how these go ...

i will take in what Gary and Albert have said in making them correct but you have to try first as see learn how to correct mistakes ..in any case i have something to work with ,its easy to make more to try different ideas.

Reason i dropped the size of the Nipkow i needed the Nipkow to match the lens area.


i will wash off the paper templates and check holes .

[gary]

Hi Harry, it's hard to tell from these pictures but that cutter and the holes look awfully large - did you go all the way through with that? can you measure the diameter?

Since you seem to have scaled my files down can you tell me how far in from the edge the spiral starts? I can then give you a new aperture size.

Other than that they look good - I suggest you try them just as a monitor to begin with.

[Harry Dalek]

Gary, Harry, to maintain a datum if cut oversized how about a piece of brass rod with needle sized hole drilled through (that's about .5mm dia plus to suit).

Taper the end (and maybe serrate) and place the needle point onto the datum mark on the CD before piercing.
Whilst holding the needle vertically, slide the rod down and twist to mark (CD marking ink on end?)
This gives a fixed datum dia same size as needle for future reference if needed.

Hi Albert

I like the idea of the brass thing as a stopper to keep the hole sizes the same .

i was thinking of using a Permanent marker and mark the needle ,i know in DIY shows they use tape around the drill bit same sort of idea as your brass rod.

Its amazing really how you can see passed a hole that is just a pin prick size when you hold it up to your eye it amazes me more my eyes can do it still

[Harry Dalek]

Hi Harry, it's hard to tell from these pictures but that cutter and the holes look awfully large - did you go all the way through with that? can you measure the diameter?

Since you seem to have scaled my files down can you tell me how far in from the edge the spiral starts? I can then give you a new aperture size.

Other than that they look good - I suggest you try them just as a monitor to begin with.

Hi Gary

The Disks today gary are really not the end ones Just test to see what works making them a learning thing i am sure i am over the place in hole size i was more interested in making them ...i do need some sort of stopper as Albert talked about doing this stuff by hand you really need some thing like that ...No i didn't use all the needle but i can see doing it to get them all the same a stopper is needed .

I will measure the diameter let you know just wanted it to match the lens and didn't want the first holes so close to the edge of the disk thanks for the help there Gary ..

Yes just something to test with and see what happens with the light part of it .

[Viewmaster]

Holding that drilling machine I don't see how you have the required control on where the drill is going, Harry.

For myself, I prefer the slow, delicate cold needle in a holder and held very close to the pierce point for max control and seen under a fixed microscope, taking it very slow and very steady.

I never used a hot needle either as a hot needle might,
" Suddenly go somewhere where no needle has gone before," as it were , says Jim Kirk

[Lowtone]

Not for sale you have to make one if it works you can copy

aww i don't know electronics and mess up everything i try when it is complex. Too bad it is not for sale.

[Harry Dalek]

Holding that drilling machine I don't see how you have the required control on where the drill is going, Harry.

For myself, I prefer the slow, delicate cold needle in a holder and held very close to the pierce point for max control and seen under a fixed microscope, taking it very slow and very steady.

I never used a hot needle either as a hot needle might,
" Suddenly go somewhere where no needle has gone before," as it were , says Jim Kirk

Hi Albert

Its believe it or not very controllable the dremel drill is made for hobby work.

Its more albert how bothered you are taking your time as i know your pretty good at it ... i wouldn't mind a dremal bench press for it which you can buy ...that would get it pretty right at speed get all holes right.

This friction drill idea works pretty good its again how you take your time at it its better than a hot needle idea any case Albert these are for testing and were an idea to make holes i will take my time on others and do it better ....
Gary the templates are about 10cm across 10.2 really that seems about right for the lens not to close to the edge of the cd.

[gary]

Gary the templates are about 10cm across 10.2 really that seems about right for the lens not to close to the edge of the cd.

Hi Harry, no it's the distance away from the edge of the disk of the first hole that I need to know - I fear that if you are too far away the size of the aperture will become impractically small. Having a precise mask may be a better approach when using a CD disk.

[Harry Dalek]

Not for sale you have to make one if it works you can copy

aww i don't know electronics and mess up everything i try when it is complex. Too bad it is not for sale.

OH no Lowtone its hard hobby if electronics is a problem which it can be really for every one at times ,its an on going learning thing that you have to try and try and try one day it will work .

I'd love to make stuff and sell now that would be a good job ! but our hobby i like making stuff out of junk so never the same second time around and imagine trying to post nbtv stuff working i think it wouldn't once it did the trip..

I suppose copying should be easier ,one thing i did learn many years ago its very unlikely to work trying to make some thing from start to finish without testing as you go ...its almost a dead serenity once you flick that on switch nothing will happen or smoke the latter is really really not good

But you do have us if you want to make something every one will help with advice ...do it slow take your time Just ask as you go ...if you want to try what i am doing see what you have handy ...need some electronic junk for a start .

[Harry Dalek]

Gary the templates are about 10cm across 10.2 really that seems about right for the lens not to close to the edge of the cd.

Hi Harry, no it's the distance away from the edge of the disk of the first hole that I need to know - I fear that if you are too far away the size of the aperture will become impractically small. Having a precise mask may be a better approach when using a CD disk.

Oh sorry Gary its 9mm ... could be closer to the edge just choose that looks about right was thinking i will have problems with the first hole so close to the edge ....i will look into the masking off for a full size one.

Some thing i am also toying with in my mind is cutting out parts of the cd and placing gluing a thin paper or tin foil disk what remains of the cd holds the thin disk in place ...perhaps 3 or 4 arms from the center to the round outer edge between the nipkow hole areas...this would fix the thickness problem..

[gary]

Ok, Harry - if your first aperture is 9mm away from the edge your aperture size becomes:

0.196182524576204 mm

and your picture size becomes a whopping 6mm x 9mm (approx)

[Harry Dalek]

Ok, Harry - if your first aperture is 9mm away from the edge your aperture size becomes:

0.196182524576204 mm

and your picture size becomes a whopping 6mm x 9mm (approx)

Yes Gary your 1.5 spiral is good in another way i can see the size of what the picture size will be small for sure ..... but i bet next to Alberts mine would look like a movie screen

I washed off the template see how i did with the holes ...more than likely to big still i didn't go looking for the smallest pin and guessing the holes size by hand ok for a first go but i can see i will need to do pin prick size with a raster size like this .

I Plan to do the dome sensor electronics in this little old CB RF case and i will try and use 2 since i have 2 holes handy in the drilled out plugs .

[gary]

well it is certainly a thing of beauty if nothing else.

BTW is the dome sensor(fss)/light source(mps) and the modulation source on the same axis? If not the picture will not be framed...

i.e.

---modulator-------DISK---------sensor/light source----

[Harry Dalek]

well it is certainly a thing of beauty if nothing else.

BTW is the dome sensor(fss)/light source(mps) and the modulation source on the same axis? If not the picture will not be framed...

i.e.

---modulator-------DISK---------sensor/light source----

I was planning using both the dome sensors Gary ,i suppose distance apart would be more helpful picking up the light ,i did not really think about the placement of this apart from where it fits and can pick up the light ,so that has to be in line with the camera lens to one side ...theres gos sticking it on top if so .....if i am correct in saying that ?

I am still not too picky about the monitor side of it so long as i can see getting the camera in sync ,i know at the moment even with the extra half spiral i expect it will be out on the monitor but really haven't looked to much into this yet ...apart from thinking of adding a extra spiral below the camera one to line up with the monitor start position perhaps.

I was doing some of the monitor circuit tonight try and finish that off tomorrow ,need to do the motor speed control and work some thing out for the light projection....i would like to try and do this small depends how much light this thing needs...i have a small luxeon torch that gives out 190 lumens not sure what a projector gives out but must is more ..i wouldn't mind if its a in dark room only camera ..