AllSky camera nightmare….help….

[DaveL59]

I remember our dear departed Gina also had issues with her all-sky and moisture ingress, tho hers were 3D printed casings.

I wonder if it's a difference in thermal properties causing the plastics and seals to open gaps with the internal heating?

[Carbon Brush]

Silica gel absorption is a very slow process. Give it time.
Sealing the housing on a cold dry day minimses moisture trapped, reducing the burden on the silica gel.

Something else to consider. Do you know anyone who has a MIG welder? With a cylinder of argon based welding gas.
Standard argon shielding gas for MIG welders is an argon & carbon dioxide mix. Importantly no water vapour.
In some equipment I get involved with, the electronics (and more) enclosure is purged using either nitrogen or argon.
High pressure cylinders contain dry gasses.

Feed the gas in slowly at one side of the box, allowing it vent at the opposite side. OK not a 100% air purge but a big improvement.

HTH, David.

[DaveL59]

Perhaps leave the assembly open in the fridge for a couple hours and then quickly seal it up while still in there but with the door open for access? That'd be dry and cold air filling it I'd think.

[Stuart1971]

Ok, so my solution is, and thanks for all the help on this thread…

I have sealed the dome area completely from the box itself. Silicon sealant around the base of the lens holder as that where the gap was. So a much smaller volume of air to contend with. And also put a pot of desiccant in the dome and will now leave in the garage for a week or so for the desiccant to do its thing inside the dome, then I will fit back outside…I sealed it in the garage where it was colder.

So fingers crossed this works…

 

Edited March 28 by Stuart1971

[Stuart1971]

Does desiccant work best in cold or warm environment to remove moisture from the air…? Wonder if it will be better indoors for a week rather than the gargae to remove any moisture…

[Carbon Brush]

Just seen your mention of silicon sealant.
I assume this is the 'no smell' cure type? Standard sealant releases acetic acid (vinegar smell) during cure.
The chemical release from 'smellicone' sealant can cause a lot of corrosion problems in electronics.

As for leaving in a warm or cool place while the silica gel works its magic...difficult but I don't think there will be a big difference.

If there are problems fitting big bags of silica gel into anything, there is another way.
Calcium chloride absorbs a lot more moisture per Kg of product.
It changes from flakes to a lump or gel.
You would need to buy it already packaged in suitable bags. It is a single use method. No oven reset.
A further thought is that calcium chloride is quite corrosive - if it gets out of the bag.
I have encountered this compound in big applications - not in small applications.
This stuff from amazon may be worth a look.
https://www.amazon.co.uk/NATRUTH-Moisture-Absorber-Bags-Fgrance/dp/B0BHX32SN7/ref=sr_1_10?dib=eyJ2IjoiMSJ9.z7yKOZaItl_GYJbR8CsMEUKRrcPjXnItbLiAy9KimxmKfQ3vx20ZgZmLrsx9WZ0pnFpN3IYxiK4WWvB6IrftE1l7UMx4zcwapvFZbe4A7FnayMlKffZp8WEYIbOAlBL3Ll4v5OMEY8GRclSgni5jcTXfOgGlD6Sm0phE4kOE8MKm7_7UYSxTWrZ48LdfP7oQik3StPj956HcMRqZvvv6o8nY6VQNAtifCD-E1giX91o.GYATK0_cPTdaEDZ7TwCBgiuSxKM2eb9kWwY7hR_e1HM&dib_tag=se&keywords=calcium%2Bchloride%2Bdesiccant&qid=1711633995&sr=8-10&th=1

[Stuart1971]

1 hour ago, Carbon Brush said:

Just seen your mention of silicon sealant.
I assume this is the 'no smell' cure type? Standard sealant releases acetic acid (vinegar smell) during cure.
The chemical release from 'smellicone' sealant can cause a lot of corrosion problems in electronics.

As for leaving in a warm or cool place while the silica gel works its magic...difficult but I don't think there will be a big difference.

If there are problems fitting big bags of silica gel into anything, there is another way.
Calcium chloride absorbs a lot more moisture per Kg of product.
It changes from flakes to a lump or gel.
You would need to buy it already packaged in suitable bags. It is a single use method. No oven reset.
A further thought is that calcium chloride is quite corrosive - if it gets out of the bag.
I have encountered this compound in big applications - not in small applications.
This stuff from amazon may be worth a look.
https://www.amazon.co.uk/NATRUTH-Moisture-Absorber-Bags-Fgrance/dp/B0BHX32SN7/ref=sr_1_10?dib=eyJ2IjoiMSJ9.z7yKOZaItl_GYJbR8CsMEUKRrcPjXnItbLiAy9KimxmKfQ3vx20ZgZmLrsx9WZ0pnFpN3IYxiK4WWvB6IrftE1l7UMx4zcwapvFZbe4A7FnayMlKffZp8WEYIbOAlBL3Ll4v5OMEY8GRclSgni5jcTXfOgGlD6Sm0phE4kOE8MKm7_7UYSxTWrZ48LdfP7oQik3StPj956HcMRqZvvv6o8nY6VQNAtifCD-E1giX91o.GYATK0_cPTdaEDZ7TwCBgiuSxKM2eb9kWwY7hR_e1HM&dib_tag=se&keywords=calcium%2Bchloride%2Bdesiccant&qid=1711633995&sr=8-10&th=1

Yes, it’s a non smell type, as I did know about the issues with the stuff that smells of vinegar when curing…

The dome steamed up as soon as I sealed it down, and is slowly now clearing, and the desiccant is changing colour already slowly too, so hopefully it’s working…👍🏻

[tomato]

I took mine apart today to fit the heater ring, the bottom of the enclosure was very wet, so the warter is getting in somewhere. As an additional measure I am going to enclose the whole unit in a waterproof drawstring bag when not in use to hopefully drastically cut down on the moisture ingress.

The air fryer is great for replenishing silica gel bags.😉

[Stuart1971]

22 minutes ago, tomato said:

I took mine apart today to fit the heater ring, the bottom of the enclosure was very wet, so the warter is getting in somewhere. As an additional measure I am going to enclose the whole unit in a waterproof drawstring bag when not in use to hopefully drastically cut down on the moisture ingress.

The air fryer is great for replenishing silica gel bags.😉

It might not be water getting in, it may well just be the water in the air condensing inside and settling in the bottom, this is what I have found with mine, but just put mine back out now, with the dome area completely sealed and airtight from the rest of the enclosure, with some desiccant beads in there too, while it’s been sitting inside the desiccant has soaked up a lot of moisture from the small area, so should have dried the air pretty well, 🤞🏻🤞🏻 we shall see now…

[tomato]

Interestingly I left the original (more powerful) plate heaters on by mistake continuously for about 48 hrs previously and the clear dome and lens were bone dry when I dismantled the camera, but the base of the enclosure below the heated plate and therefore the coolest part of the assembly was sodden. That does point to it being a sealed system but if so, there was lot more water present than the theoretical quantity that could have condensed out of that volume of saturated air.

[Stuart1971]

Well that did not work, ☹️ the desiccant worked and the dome cleared, BUT as I have a dew heater ring inside the sealed dome, over time it heated the air up in the dome and dried out all the desiccant as it turned from green as it is when it’s working, back to orange as it is when dry and all the moisture was back on the inside of the dome this morning…it didn't help as the little pot of desiccant sits on the heater ring  as I don’t have enough space for it not too, should have realised really…as it heated the pot from the bottom…😂😂

so one more thing to try and that is to disconnect the heater ring, so that the air in the dome stays cool, maybe just a little above ambient.🤷🏼‍♂️

[tomato]

Mine was good last night, clear from start up, but it was a dry day yesterday, the test will come when it gets a proper soaking.

[tomato]

Had some rain overnight but my nylon swim bag was dry inside…

And the light exclusion cover was dry inside and out…

And most importantly the dome and camera were still clear even with the heater off…

So, fingers crossed, it might be all good now.🤞

[Stuart1971]

Well mine is in the bin now, gave up with it, even with the dome completely sealed and desiccant in there and sealed up on a very low humidity day, it rained last night and the dome was all dewed up this morning….with and without the heater ring powered….☹️☹️

[tomato]

That’s not good news. I think with all the efforts you made there must have been moisture ingress somewhere. I noticed some moulding marks on the flange of the dome which would create a sealing issue, I filled them and sanded the flange smooth but I still think standing water was seeping in. The base plate heaters got everything toasty by the end of a session and when it cooled down I think there was the driving force to cause water ingress. 
 

Maybe a £3 swim bag might be worth a try?

[callisto]

2 hours ago, tomato said:

Had some rain overnight but my nylon swim bag was dry inside…

And the light exclusion cover was dry inside and out…

And most importantly the dome and camera were still clear even with the heater off…

So, fingers crossed, it might be all good now.🤞

What Len's are you using in the setup if you don't mind me asking? 

Mark.

[tomato]

I purchased it used from ENS optical, Birmingham. They always have some suitable ASC lenses in stock:

Search - all sky camera lens (ensoptical.co.uk)

[Stuart1971]

1 hour ago, tomato said:

That’s not good news. I think with all the efforts you made there must have been moisture ingress somewhere. I noticed some moulding marks on the flange of the dome which would create a sealing issue, I filled them and sanded the flange smooth but I still think standing water was seeping in. The base plate heaters got everything toasty by the end of a session and when it cooled down I think there was the driving force to cause water ingress. 
 

Maybe a £3 swim bag might be worth a try?

Why would I want to cover it, with a bag, it’s on all the time..? 🤔

Edited April 1 by Stuart1971

[tomato]

That would indeed be a problem, but I use mine purely to monitor sky conditions when imaging. Also I found having the sensor exposed to sunlight all the time was generating lots of dead pixels so now the covers only come off at night.

 

[Stuart1971]

9 minutes ago, tomato said:

That would indeed be a problem, but I use mine purely to monitor sky conditions when imaging. Also I found having the sensor exposed to sunlight all the time was generating lots of dead pixels so now the covers only come off at night.

 

Ah, ok that makes sense, I like to see the startrails image generated each morning if it was a clear night and the Timelapse, I just have it out for about 6 months of the year…and I too also use as a cloud cam while imaging…