ASC Questions and Options

[DaveS]

Thinking about an ASC and putting together a parts list while considering my options.

So far:

ASI178

1.55mm f/2 220 deg fisheye lens

Dew heater[

2.9mm Dome

 

Now the options.

As I see it there are two broad possibilities

A "dumb" box with just USB3 and power connections to the obsy computer and RDP'd from the office, but the USB3 will need to be quite long as the logical position to give good coverage is on the west support post of the roof rails, at leat 5 metres, possibly more so a powered repeater needed.

A "smart" box with a RPi running the capture software and RDP'd to the office computer.

Is the latter feasible?  Will a Win10 computer connect to an RPi running a flavour of Linux?

 

Beyond this, to cool or not to cool?

For cooling I'm thinking of using a cast ali box with the hot side of the peltier cooler in contact with it and possibly some fins on the outside. I'm only looking to reduce the camera temp to about 0 deg, so not looking to a water block. May need a metal block to support the camera at the right height.

 

OK, that's enough for now, more questions later.

[Gina]

I'm inclined to agree that a waterblock is almost certainly overkill.  When I decided to water cool, I was using a different, less sensitive camera.  I'm even considering redesigning my ASC and making things simpler.  OTOH I have all the water-cooling kit so might as well use it.

[Gina]

As you know, I'm using an RPi right at the camera thereby reducing the USB cable to almost nothing and needing only power connections.  I have all the info on this including step-by-step instructions.  But whether anyone follows my example is entirely their choice, of course.

[DaveS]

Thanks Gina

My instinct, based on experience is KISS, as I doubt my electronics abilities now. To that extent it might be simpler to run a USB3 to the obsy computer, but whether it would be effective is another matter

If I had a cooling fan on the camera I could use an ABS box, but where to draw the air in from is another matter.

[Dr_Ju_ju]

Just bare in mind that USB 3.0 cables are usually much shorter that USB 2.0

[Gina]

You don't need to use USB3 for an ASC - USB2 is fine.  That's what I'm using.  The only advantage of USB3 is a shorter download time.  With an ASC you will probably use an exposure of 60s for nighttime when it's dark.  A few seconds download time is no problem.  You can go up to 5m with USB2.  In daytime you will want to use the minimum exposure of 32 microseconds, but still not want to image more than once or twice a minute.

I have my ASC mounted on an aluminium pipe on a bracket on the north wall of the obsy roughly NW of the pier where I tend not to image much.

[Gina]

27 minutes ago, DaveS said:

Thanks Gina

My instinct, based on experience is KISS, as I doubt my electronics abilities now. To that extent it might be simpler to run a USB3 to the obsy computer, but whether it would be effective is another matter

If I had a cooling fan on the camera I could use an ABS box, but where to draw the air in from is another matter.

That sounds sensible.  Only do what you feel comfortable with - it's all for your own enjoyment, after all.

[Gina]

This is something I considered for cooling the hot side of the Peltier TEC.  It uses purely convection cooling (or if outside, wind if there is any).

On 11/10/2019 at 18:56, Gina said:

This looks pretty amazing - I think it might actually work.  NOFAN

 

[Gina]

An earlier ASC looked like this.  That was alright until a storm ripped it off the obsy roof and spread the contents far and wide!!  Got the Passive Cooler from Amazon.  They're now black anodized, mine was ali coloured.