Aurora EL flat panels

[pixueto]

Can someone using one of these give me some advice?

I have the 220 and it's powered from the car lighter through the inverter. Any idea of a cheap way of connecting it tho the wall and being able to regulate the light intensity?

How should I go about cleaning the panel? Should I take as much care as with an eyepiece?

Thanks for your help

[Stephen]

I can't remember the price, but I got my panel from GN direct and purchased a wall adapter with it.

[pixueto]

Thanks for your repply. I got mine from FLO, I had to take it to the car to test it! Did yours come with a connection to the car lighter too? What kind of wall adapter is that?

[Dave Smith]

I also got mine from FLO. The panel itself is mounted between two sheets of translucent perspex. I don't think the surface is as critical as a lens or mirror surface but I would try to avoid any scratches as they could get filled with grime and then the light would no longer be uniform.

I power mine from a Maplin regulated power supply which also powers my mount and dew heaters. I believe it can be dodgy trying to make it dimmer by altering the supply voltage. The recommended way is to insert sheets of plain white paper between the panel and the telescope.

It also works fine from a Skywatcher portable power supply.

Dave

Dave

[ollypenrice]

I agree with Dave that you should regulate the brightness using paper or a white T shirt etc. Scratches will be way out of focus but you'd be better without them!

Olly

[Stephen]

Thanks for your repply. I got mine from FLO, I had to take it to the car to test it! Did yours come with a connection to the car lighter too? What kind of wall adapter is that?

Yes the cigar adaptor came with it as standard.

Off the top of my head (at work at present) the additional adaptor is a variable voltage thing that plugs into the wall, then plugs into the inverter.

[ianaiken]

Why would we want to regulate the brightness and make it dimmer? Is the aim to have a flat with a long exposure with a max ADU of say 22k? Surely you can just alter the exposure time to get the appropriate ADU rather than adjusting the intensity of the light?

This question is open to all and not just OP. I'm curious, my flats are taken with 0.3 second exposure. I don't dim my panel (which I got from FLO). I have read some people say this is too fast and flats should be longer exposure without really saying why. Is there a reason?

[pixueto]

I also got mine from FLO. The panel itself is mounted between two sheets of translucent perspex. I don't think the surface is as critical as a lens or mirror surface but I would try to avoid any scratches as they could get filled with grime and then the light would no longer be uniform.

I power mine from a Maplin regulated power supply which also powers my mount and dew heaters. I believe it can be dodgy trying to make it dimmer by altering the supply voltage. The recommended way is to insert sheets of plain white paper between the panel and the telescope.

It also works fine from a Skywatcher portable power supply.

Dave

Dave

Thanks Dave. Could you give me details of your power supply? The panel connects to the inverter with a jack I hadn't seen before. Is there a way to connect the inverter to the PS whilst being able to regulate the light intensity? Sorry if this is a dumb question!

[pixueto]

Yes the cigar adaptor came with it as standard.

Off the top of my head (at work at present) the additional adaptor is a variable voltage thing that plugs into the wall, then plugs into the inverter.

Thanks Stephen. Can you give me the detais of that adaptor? Thanks.

[pixueto]

I'm happy to report that I've tested the panel with the camera in AV mode and it seems to work really well. The histogram was located slightly to the right, at about 70% of the scale. Also, I downloaded the pictures to inspect them at 110% magnification and the picture was a white continuum everywhere. I don't normally use any filters; only my Canon 350D in prime focus so I gess I don't need to dim the light or use any sheet of paper.

Am I right?

Thanks for your help.

[Dave Smith]

Thanks Dave. Could you give me details of your power supply? The panel connects to the inverter with a jack I hadn't seen before. Is there a way to connect the inverter to the PS whilst being able to regulate the light intensity? Sorry if this is a dumb question!

This is the power supply that I use http://www.maplin.co.uk/13.8v-regulated-mains-power-units-231

Mine is the 10A version that doesn't seem currently available. However mine is to run everything, mount, dewheaters and the panel. If you only want to run the panel something much more modest will suffice. As I said before, it is not agood idea to regulate the light intensity electrically. If needed just cover the fron with layer(s) of paper.

Dave

[ianaiken]

I would have thought you could put the camera into manual mode and not AV and just set the shutter speed yourself therefore controlling how much light enters the camera therefore not needing to control the light intensity? A shutter speed of 3 seconds lets in more light than 1 second, so you would adjust until your histogram was in the right place for your flats. I think with my 40D it was around 1/8 of a second

[Spikey]

I use a maplin 12v power supply which in turn powers a 4way 12v car lighter distribution box. When taking flats with a DSLR my GN EL panel plugs into one of those and sits on top of the scope. With the DSLR I use APT and one of the flats plans which utilises AV mode and alters the exposure automatically and it works really well. I've also taken flats in manual mode and just made sure the histogram is about 2/3rds of the way across to the right and they seems to have worked well also.

[Stephen]

Thanks Stephen. Can you give me the detais of that adaptor? Thanks.

There's not really any details I can give I'm afraid, it's a wall plug that has a switch on it to change voltage : and a plug on the end that goes in the inverter

I also don't filter the panel in any way, nor do I use AV. It only takes 30s to find the correct exposure length in manual to get the histro half to 2/3 the way up

[Spikey]

I also don't filter the panel in any way, nor do I use AV. It only takes 30s to find the correct exposure length in manual to get the histro half to 2/3 the way up

Don't get much choice when you use a CCD

I can't get used to calling you Stephen

[Stephen]

Don't get much choice when you use a CCD

I can't get used to calling you Stephen

How so? I must confess I've not used the panel yet with my Atik however the 450D required about a 1/80 to 1/200 exposure, and the Atik min exposure is 1/1000.

You'll get used to it

[Spikey]

I meant between the AV & manual

At least you'll only have to take one set of flats with the Atik OSC mate.

[Stephen]

I meant between the AV & manual

At least you'll only have to take one set of flats with the Atik OSC mate.

DOH! I get you now

Anything for an easy life me

Old mono is in new hands now and getting much more use than I ever did with it.

I'd just rather go out there on the rare night I have time / energy / skies and just fire off a load of subs than dither around trying to get 4 channels through ....

It's currently at the local PO : waiting to see if I get a parcel tomorrow or a nasty letter from HMRC asking me for money ....

[pixueto]

I would have thought you could put the camera into manual mode and not AV and just set the shutter speed yourself therefore controlling how much light enters the camera therefore not needing to control the light intensity? A shutter speed of 3 seconds lets in more light than 1 second, so you would adjust until your histogram was in the right place for your flats. I think with my 40D it was around 1/8 of a second

I see. I'm new to all this and I haven't managed to take proper flats yet. That's why I went for the aurora panels.

Thank you all for your help.

[ianaiken]

If your using something like APT or BYEOS to control your canon then the software picks your exposure time for you when you have selected flats however I still preferred to set my own exposure time.

[pixueto]

If your using something like APT or BYEOS to control your canon then the software picks your exposure time for you when you have selected flats however I still preferred to set my own exposure time.

Why do some people use sheets of paper if you can select the exposure time get the histogram in the right place? I don't get it.

[Gina]

Maybe the light is too much for the camera at minimum exposure? Seems unlikely though. Is the EL panel brighter than a cloudy sky?

[ollypenrice]

Exactly. Some CCD cameras in fast systems are simply too sensitive and even the shortest exposure is too much. It's marginal for me when using the F reduced Tak and in Yve's system a lot of dimming material is required.

Also several of us using big reflectors have been struggling with flats and it turns out (thanks to some ferreting by RobH) the well depth isn't necessarily 65000 but less than half that. To expose to one third on Yves' setup seems to require only 8000 ADU which is why we may have been struggling with flats taken at 30,000 ADU. To get down to 8000 will need lots of paper!

Olly

[pixueto]

Thank you all very much. I've learnt a lot from this thread. Hopefully I'll be able to put the theory into practice if this weather give us a break!