First Light for my new Wide Field Rig

[nebulosity. (Jo)]

I have finnished the first stage of cooling my 350D and I thought I'd better try it out and see if it works

Only had an hour before the moon came up so just a quick one.

It's around the bottom of Cygnus, NGC 7000 and Gamma Cyg Nebula shot though a pretty dirty sky 15 degrees above the horizon

I took darks and flats but had some dramas with processing so in the end just used the lights.

60x60sec subs, Canon 350d Iso 800, Nikon 85mm lens F four.four (the four key has died on my key bourd )

Would have been nice to get some more subs but as this was only a test run I'm not real worried.

Thanks for looking,

Jo

[lazjen (Chris)]

Nice test run.

Tip for getting a '4' - cut'n'paste it.

[rcheshire (Rowland)]

Looks good Jo. What temperature did you image at?

[nebulosity. (Jo)]

Thanks Chris and Rowland,

I'm not real sure what temperature I was imaging at as I haven't got a temperature probe on the cold finger yet, I'll put one in next full moon when I do some more mods to it. I'm going to add another heat sink and fan, larger TEC and put in temperature control, I figure if I'm going to have cooling I might as well do it properly

Jo

[rcheshire (Rowland)]

In for a penny, in for a pound. 28C is pretty darn good, all the same. If it helps. My first mod was 12V 8A with a 0.2 C/W heatsink = 34C differential. What temp are you aiming for?
http://www.micforg.co.jp/en/c_fhce.html

[nebulosity. (Jo)]

Originally Posted by rcheshire

In for a penny, in for a pound. 28C is pretty darn good, all the same. If it helps. My first mod was 12V 8A with a 0.2 C/W heatsink = 34C differential. What temp are you aiming for?
http://www.micforg.co.jp/en/c_fhce.html

The TEC I have at the moment is a 15v 8A 55w, but my power supply can only keep up with 11v 8A, so I got a new one that runs at 12v 6A 60w. I'm sort of hoping I can get a max 40c differential and be able to keep it at an even 35c with the temperature control. Would this be possible you reckon? The good thing is I don't have to worry about dew problems with my purged case

By the way I've been able to mount the screen and buttons on the out side of the case which means I can now work all the settings without a computer

Thanks for the link and interest in this Rowland Pretty much all I know I've learnt from reading your cooling threads and from your input

Cheers
Jo

PS. What does 0.2 C/W mean?

[multiweb (Marc)]

Nice flat field. Beaute shot.

[nebulosity. (Jo)]

Originally Posted by multiweb

Nice flat field. Beaute shot.

Thanks Marc, just wondered how you focus for your wide fields? I made a baht mask but it doesn't work properly with my lenes

Cheers
Jo

[multiweb (Marc)]

Originally Posted by nebulosity.

Thanks Marc, just wondered how you focus for your wide fields? I made a baht mask but it doesn't work properly with my lenes

Cheers
Jo

Some nights I get lucky. Seriously, very hard. If it's still with good seeing I do it by the numbers in nebulosity. It's quite easy. If the seeing is not good then it's near impossible and it's an educated guess. I have small bathinov masks too. One with very fine slits and one with coarse ones. If you slew to a very bright star and do a 5s exposure then stretch you can see it. Problem is that the iris already makes diffractions spikes so it's not obvious at first but with a bit of practice you get there. Once I have my brackets for my focuser motor I'd like to give a go to Focusmax see if it does a better job at it. But I'm no there yet. Once you're in focus tape the side of the lens and stick a sock with a hottie on top. That won't move for days.

[renormalised (Carl)]

Originally Posted by multiweb

Once you're in focus tape the side of the lens and stick a sock with a hottie on top....

Does it matter if she's blonde, brunette or a redhead?

And, she only has to wear a sock

[multiweb (Marc)]

Originally Posted by renormalised

Does it matter if she's blonde, brunette or a redhead?

And, she only has to wear a sock

I don't think it matters. I all happens in the dark.

[rcheshire (Rowland)]

Jo. You can try for 40C, you'll be pretty close anyway. With a fair bit of help from IIS member Garbz I've improved the pwm circuit. Is that the way you want to go?

[nebulosity. (Jo)]

Originally Posted by multiweb

Some nights I get lucky. Seriously, very hard. If it's still with good seeing I do it by the numbers in nebulosity. It's quite easy. If the seeing is not good then it's near impossible and it's an educated guess. I have small bathinov masks too. One with very fine slits and one with coarse ones. If you slew to a very bright star and do a 5s exposure then stretch you can see it. Problem is that the iris already makes diffractions spikes so it's not obvious at first but with a bit of practice you get there. Once I have my brackets for my focuser motor I'd like to give a go to Focusmax see if it does a better job at it. But I'm no there yet. Once you're in focus tape the side of the lens and stick a sock with a hottie on top. That won't move for days.

Thanks Marc, I tried focussing with Nebulosity and I think I got lucky

Am now getting some nice subs of SMC

Jo

[nebulosity. (Jo)]

Originally Posted by rcheshire

Jo. You can try for 40C, you'll be pretty close anyway. With a fair bit of help from IIS member Garbz I've improved the pwm circuit. Is that the way you want to go?

Good to hear that 40C should be possible, am certainly interested in the pwm circuit, Pwm would be pretty much the only way to go wouldn't it?

cheers
Jo

[Rex]

Nice shot Jo. Can't wait to see a serious shot if this is just playing around. Great work!

[rcheshire (Rowland)]

Originally Posted by nebulosity.

Good to hear that 40C should be possible, am certainly interested in the pwm circuit, Pwm would be pretty much the only way to go wouldn't it?

cheers
Jo

PWM - some would say no and perhaps some of the DIYs would like to offer an opinion. I like it. More complex but easier to operate for consistent temperatures. I'm just posting a revised circuit diagram in the ATM section. It would be great to get feedback.