DIY all-sky cam?

[Gonzo]

I will have to make my own yes.

Found the following article on how to do it (I'm sure there are hundreds more on the interweb...)

http://www.skyandtelescope.com/astronomy-equipment/everybodys-do-it-yourself-dew-heater/

[Gonzo]

Looks like tonight is a clear night, I will be testing it by taking a timelapse of the night. However I will not go to bed at 3am like his morning.... damn, this astro thing can be addictive.

No wonder I got no time to work on the Mustang

[Gonzo]

So my first timelapse, day time.

I know it's only 5 seconds long...

Took slightly over one hour of capturing pictures every 30 seconds.

Will have to do more reading on how to do this properly, this is the first time ever I do it.

Things I need to do now that I know it works is to buy that expensive proper fish-eye M12 lens, cost is around £40.

Is my low cost box up to the task compare to a proper all-sky camera, I think it does the job ok.

It will be used to check for cloud cover and to do the occasional video streaming / timelapse video / odd pictures here and there.

fun in making it: 10/10

[Gonzo]

Just started a 6 hours capture....

 

here's one shot from the Raspberry PI NoIR camera:

Just realised the naming my file, day_lapse ..... doh, it's night time. Oh well, can't be bothered to start again. lol

Looking out through my roof window, I can't see that many stars. It's still a bit cloudy and with London's light pollution... not much fun.

But got to say, with a 1 sec exposure time (that's the max this camera can do) it's OK

[Gonzo]

Just seen my timelapse from last night, wow, just wow.  Sadly, can't seem to be able to upload the video to youTube at the moment. Will do it from home later on.

[Gonzo]

I have now managed to upload the video, here it is:

(don't mind the end of the video, early morning, too much exposure = censor washed out.

Do I see stars? checked

Do I see moving clouds? checked

Is it a success: yes it is

Waiting for a few more sensors to turn up so that I can finish this box as the weather station too.

[Horwig]

OK, so I've got my QHY5 working as an all sky camera. I'm using PHD2 as my viewer, cos it looks as if it subtracts darks from the display, not just the processed images like PHD1.

This is ongoing tonight, two instances of PHD 2.3.0 and Maxim.

H

[Gina]

That's interesting, I have a QHY5 I'm not using

[ChrisLX200]

FireCapture will use dark frames too, whilst HandyAVI has a better capture method but it will not utilise dark frames. I had an email discussion with the author of HandyAVI a couple of months ago and he said he was going to modifiy the program to use dark frames but I've heard nothing since.

ChrisH

[tekkydave]

That's interesting, I have a QHY5 I'm not using

Project Alert !!!

[Gina]

Project number 1001

[JamesF]

The one concern I've not been able to resolve for a largely home-built all-sky cam made using, say, a QHY5. is what to do about the Sun.  "Proper" cameras have an auto-iris system as I understand it.  Cameras without are going to be focusing a lot of bright light onto a small area of the sensor during the day and probably doing it no good at all unless there's some other solution.  Anyone have any clever ideas?

James

[pete_l]

 Anyone have any clever ideas?

Arduino, light sensor, stepper motor.

When the Arduino detects it's daytime it rotates the camera (which is connected to the stepper) 90° to the north.

So long as the electronics inside the dome doesn't cook, and there's space, it should be OK.

Plan B would be to rotate a crescent shaped shade to cover the sensor. That could be either inside or outside the dome.

Plan C would rotate the whole sky-cam assembly.

[JamesF]

Hmmm.  Perhaps a piece of Baader solar film could be rotated over the camera at sunrise and removed at sunset

James

[tekkydave]

How about a small solar cell that moves a shade over the camera lens via a small dc motor or servo. It could have a small return spring to pull it back out of the way at night.

[Gina]

Some interesting ideas there

Oh dear, so much to do so little energy...   Can't do everything at once anyway.   And I've got the roll off roof to automate too...

[Horwig]

Yes, burns on the sensor are worrying me, think it might be a cover manually placed over the camera when not observing, till I come up with a better, automated, solution, that is.

H

[Gina]

The problem is now residing in my mind - there is always the possibility of the odd idea rising to the surface

[Horwig]

Can I show you these, so your mind can evaluate them Gina?

http://www.technobotsonline.com/miga-nanomuscle.html

http://www.ebay.co.uk/itm/2-5watt-5v-500ma-usb-solar-panel-charger-/291187576943?pt=UK_Gadgets&hash=item43cc21d06f

Would need some mechanical amplification, i.e. a lever, but might it work?

H

[Gina]

The blurb says the NanoMuscle is only really suitable for intermittent loads whereas we want the shutter to operate and stay operated until the sun goes in.  Very interesting though

I think an electromagnetic actuator would work though - doesn't take much to operate a shutter.  eg. Magnet, coil and spring.

[Gina]

BTW - What lens do you use with the QHY5 for 180 degrees coverage?

[kalasinman]

Just as a reference...re:5vdc-12vdc . Simple dc-dc voltage converters are cheap, adjustable over a wide range, and easy to use. They work either step down or step up. Some include a small digital read out.

[tekkydave]

Would a small solar panel, say 4" x 3" generate enough juice to move a servo? I haven't used servos before so not sure. Is there any space in the dome for it? Maplin do small solar kits for kids that have them although the one I have contains a small DC motor not a servo.

http://www.maplin.co.uk/p/6-in-1-educational-solar-kit-a86jr

[Horwig]

One of these Gina, It's not the same one that SBIG use, they use the MUCH more expensive lens, but this is ok. :http://www.fujifilmusa.com/products/optical_devices/security/fish-eye/vari-focal/yv22x14a-2/

As to power for an actuator, I've got 12v feeding the dome for the anti dew, so I don't need the solar cell, just a light sensor to switch the shutter on and off, the anti dew could come on when the shutter is open, off when shutter closed, that would be quite neat.

H

[Gina]

One of these Gina, It's not the same one that SBIG use, they use the MUCH more expensive lens, but this is ok. :http://www.fujifilmusa.com/products/optical_devices/security/fish-eye/vari-focal/yv22x14a-2/

As to power for an actuator, I've got 12v feeding the dome for the anti dew, so I don't need the solar cell, just a light sensor to switch the shutter on and off, the anti dew could come on when the shutter is open, off when shutter closed, that would be quite neat.

H

Thanks   That doesn't look cheap    How much was it and where can you get it in the UK?  I was thinking more in terms of a CCTV camera lens.

One advantage of using a photovoltaic cell to drive an actuator for the shutter is that it would still work in a power cut or if the power connection should somehow fail.  I think the sort that power garden lights might do.  That would need an actuator that would operate with current applied and return to the shutter open position when the current dropped off.  Something like the mechanism in an analogue meter was what I had in mind.  I guess you could adapt an old meter - choose a robust one preferably.  Of course a DIY expert could make their own using a rare earth magnet and a coil of wire with a light spring for return.