Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 5, 2014 23:30:49 GMT
I think the stuff is called RAIN X. Pretty cloudy here tonight, so no dew yet. No stars either.
I'm hoping any heat generated by the cam might keep the dome clear, but The 2 cctv housings I found both had heaters in them and one had a 24V transformer. I have yet to test it, but can allways get another if needed.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 6, 2014 23:40:36 GMT
Well this seems to be as good as I can get it. I've set a DSS at x32, max contrast and brightness at 42. Lots of hot pixels if I turn up the brightness.With the dome on any light source, even the moon, gives glaring artifacts all over the image. Even a fingerprint shows up something horrible. I'll try giving it a better clean tomorrow as I may have touched it again when doing the final focus tonight. Perching on top of a ladder at midnight with a laptop on the roof is not an ideal scenario, but that was the only way to focus the cam, and it was a right mare. Anyone seeing me would have thought I was nuts. Here is a screen capture of the best I could get with a decent clear sky.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 6, 2014 23:42:53 GMT
Same problems I had Allan, any bright outside light will cause nasty reflections on the dome
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 7, 2014 0:04:39 GMT
Its a problem I cannot find an easy solution to. If I rotate the cam and view the sky from NE to SE the street lamp does not affect the dome and I get a clearer pic. Any other direction is affected. I can still raise the housing by about 3 feet more and that may help a little, but then it may be subject to wind movement. more experimentation needed. HEY guess what. As I am typing this and looking at my skycam, I just saw my first meteor flash by on the screen, so it does work as intended. the meteor only left a trail about 1/2" on the screen, but at least I saw it. Feeling not quite so disillusioned now.
|
|
|
Post by johnno on Jul 7, 2014 0:15:26 GMT
Allan, when I captured the Perseids I had senseup at X4
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 7, 2014 0:21:46 GMT
Hi Allan the moon I have found will blast the stars from the sky which is a bummer its due to using the high intergration not much you can do. Maybe worth testing it in different locations to see if you can find a sweet spot when the streetlights are on.
Good to hear you got a catch!
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 7, 2014 6:17:09 GMT
Johnno, I realise that I will have to find the optimum senseup for the conditions on the night. Last night was a half moon. It will probably get worse as the moon gets more full. At least with the cam above the roof, I can now scan the sky in a direction away from the glare of the moon.
Next small mod is to shorten the video cable as it is way too long and is coiled up at the moment. I have phase lines so I need to clean up the signal. I have used a dc battery and transformer, but the phase lines persist.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 10, 2014 21:20:05 GMT
Another update. I could not tolerate the annoying reflections and artifacts on the dome ruining my image, so I ditched the dome and went to phase 3, or 4, or 5 maybe. Anyway, I replaced the dome with a flat glass version.
It performs much better and any stray light from moon or streetlamps is far less intrusive. My conclusion is that domes are best suited to dark sites. Upon testing last night, I had a strange shadow in the image which looked just like a profile of my lens, so in case it was created by the grey interior of the top housing, I have painted it matt black inside and also painted the edge of the glass disc. The 4" glass disc is 3mm thick and cost £5. Far cheaper than the dome, and less prone to scratching.
Awaiting a dark clear sky for testing.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 10, 2014 22:19:51 GMT
Another update. I could not tolerate the annoying reflections and artifacts on the dome ruining my image, so I ditched the dome and went to phase 3, or 4, or 5 maybe. Anyway, I replaced the dome with a flat glass version.
It performs much better and any stray light from moon or streetlamps is far less intrusive. My conclusion is that domes are best suited to dark sites. Upon testing last night, I had a strange shadow in the image which looked just like a profile of my lens, so in case it was created by the grey interior of the top housing, I have painted it matt black inside and also painted the edge of the glass disc. The 4" glass disc is 3mm thick and cost £5. Far cheaper than the dome, and less prone to scratching.
Awaiting a dark clear sky for testing.
Allan, I'm loving this little project and I want one! I have a PTZ camera that is not great in the dark and I'm thinking of maybe sticking in a decent cam and popping it on the roof upside down so I can pan right round and have control from the office. This would be my early cloud warning system and double up as a nice meteor cam. Look forward to the test results
|
|
|
Post by davy on Jul 10, 2014 22:38:40 GMT
hi allan,,great mod and you came to the conclusion I was thinking about..i wondered if with using the dome that it may act like a fish eye and have good focus on the center of the dome but stray off focus to the edges..as with a dslr..did you do any mod on adding a heater to the project.. I was thinking along the lines as I think it was john and use 100 ohm resistors to gently warm at the glass side if it was viable and to try and fit a variable resistor to control it,i would also concider using a fan in back end to act as a demister..food for thought maybe..davy
|
|
|
Post by davy on Jul 10, 2014 22:41:19 GMT
have you thought about putting the batman logo on it....lol
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 10, 2014 23:46:43 GMT
hi allan,,great mod and you came to the conclusion I was thinking about..i wondered if with using the dome that it may act like a fish eye and have good focus on the center of the dome but stray off focus to the edges..as with a dslr..did you do any mod on adding a heater to the project.. I was thinking along the lines as I think it was john and use 100 ohm resistors to gently warm at the glass side if it was viable and to try and fit a variable resistor to control it,i would also concider using a fan in back end to act as a demister..food for thought maybe..davy davy, I didn't notice any coma effect at the edges of the image. so I don't think using a dome has that kind of negative effect.
The negatives for me was, that due to the extreme DOF of these lenses, even when focussed at infinity, dirt or fingerprints on the dome could be seen as a dustbunny or a big bright smudge. raindrops were quite clearly seen. I tried placing the lens even closer to the dome on my second trial, and still, every mark could be seen. It got to the point where the lens was almost touching the dome, so I thought having a dome with this lens seemed pointless when a flat glass would do the same job. Bare in mind, this is not a fisheye lens, but does provide a decent fov. The other downside was that stray light caused terrible artifacts through the image in a magnified form. A bit like pointing a dslr with a wide lens too close to the sun.
With the new version, the stars are points of light right across the frame and the stray light reflections are much less intrusive. The bright smudge in the image is the streetlight, and the two larger spots are artifacts from the light. With the dome, these were magnified and more of them. This was taken at 12.45am with a bright almost full moon.
I may add a Batman logo if it helps. The demister is in the to do list. I have a couple of demisters to try out.
|
|
|
Post by davy on Jul 11, 2014 1:19:15 GMT
looking good mate/
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 11, 2014 2:48:54 GMT
hi allan,,great mod and you came to the conclusion I was thinking about..i wondered if with using the dome that it may act like a fish eye and have good focus on the center of the dome but stray off focus to the edges..as with a dslr..did you do any mod on adding a heater to the project.. I was thinking along the lines as I think it was john and use 100 ohm resistors to gently warm at the glass side if it was viable and to try and fit a variable resistor to control it,i would also concider using a fan in back end to act as a demister..food for thought maybe..davy davy, I didn't notice any coma effect at the edges of the image. so I don't think using a dome has that kind of negative effect.
The negatives for me was, that due to the extreme DOF of these lenses, even when focussed at infinity, dirt or fingerprints on the dome could be seen as a dustbunny or a big bright smudge. raindrops were quite clearly seen. I tried placing the lens even closer to the dome on my second trial, and still, every mark could be seen. It got to the point where the lens was almost touching the dome, so I thought having a dome with this lens seemed pointless when a flat glass would do the same job. Bare in mind, this is not a fisheye lens, but does provide a decent fov. The other downside was that stray light caused terrible artifacts through the image in a magnified form. A bit like pointing a dslr with a wide lens too close to the sun.
With the new version, the stars are points of light right across the frame and the stray light reflections are much less intrusive. The bright smudge in the image is the streetlight, and the two larger spots are artifacts from the light. With the dome, these were magnified and more of them. This was taken at 12.45am with a bright almost full moon.
I may add a Batman logo if it helps. The demister is in the to do list. I have a couple of demisters to try out. Hi, In all my all sky camera units, both daytime & nighttime, all have heaters and fans. A heater block near the dome and a fan low in the base keeps the air circulated and the dome frost free. I have made similar units for two all sky DSLR's with 8 mm fish-eye lenses. On the outside of the dome I have a heater wire with an internal controller, wireless control from outside, so I adjust the heat band until any dew disappears, add a tad more to keep them frost free during the night. Using quality acrylic domes and quality lenses, I do not get any distortion, I do if using cheaper lenses and cheaper domes. Quality in images never comes cheap I have found. If you don't want 180-degree view, then plane glass plates work just fine.
Clear skies
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 11, 2014 11:06:18 GMT
Great work on this Allan looking good!
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 27, 2014 16:21:01 GMT
Having climbed to the roof at midnight to change the angle of view by tilting the cam, I added a high tech solution to the problem today. This will allow me to tilt and rotate from just outside my door at ground level. Fortunately my housing is top heavy so when I release the bracket clamps, the cam housing goes almost horizontal. So, pull string down to tilt up, let string up to tilt down. Works lovely.
|
|
|
Post by davy on Jul 27, 2014 17:08:41 GMT
keep it simple works for me too
|
|
|
Post by Dragon Man on Jul 28, 2014 5:49:48 GMT
Very clever Allan
|
|
|
Post by johnno on Jul 28, 2014 11:34:26 GMT
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Aug 6, 2014 20:03:38 GMT
With my remote tilting mechanism (string) I don't have to climb so often.
|
|