Bobby1970

Noted on the "no fan" idea. 

Thanks guys. 

I could stick a variable resistor in line with the fan I guess and reduce the speed to an acceptable noise level maybe, while still cooling the heatsink. 

I just wondered if the fact that the heatsink is 40x40x20mm, it may have been enough without the fan. 

I'm just making it up as I go tbh. Lol

7 minutes ago, Adam J said:

You dont really need to go sub zero and it will solve a few issues if you dont.

Adam

I am wondering if I can run it without the fan. Need to do some more testing. See how it goes without it. 

Made some more of the foam insulating jacket. 

Had some thin self adhesive black foam left over from something so.covered the insulation around the main body with that too. 

So, today I started with some insulation around the main part of the camera body and pit the camera on test for around ten mins. Insulation around the main body seemed to do a good job, need to make some smaller bits for around the rest of the camera and heatsink/peltier as there was still moisture there. Sensor window still fogged up temp 3-4 Deg after 10 mins or so. 

Next I reversed the fan so it was pulling air from the heatsink and out into the ambient air. Within 10 mins the temperature had gone from an initial 20 odd Deg. Down to sub zero. 😨. There was actually frost on the rear of the camera lol. It leveled off at around -0.2-03 Deg. Sensor window still fogged up. 

My current conclusion is. 1) I still need some sort of dew heater for the front of the cam. 2) I will deffo need some temp control lol. And 3) the fan may be too loud. Lol. 

1 minute ago, Neil H said:

Is it dewing up because the air is being blown into the camera so sensor  face is getting very cold  . Would it do this if the air was being pulled from inside to outside may be sensor would not get as cold so the battle begins 

Heat one side cool the other ???

thats certainly worth exploring. I have a dew heater wining its way to me so will be working more on the cooler during the week i would think.

1 minute ago, Neil H said:

Hi i use the celestron power tank and you can use the usb and not the telescope out put or the telescope out and not usb

I also use a powerpack it fits in my pocket and has a large amp hour rate 

https://www.amazon.co.uk/gp/slredirect/picassoRedirect.html/ref=pa_sp_phone_search_atf_aps_sr_pg1_1?ie=UTF8&adId=A011655815U4ZWTX2NMX2&url=%2FStarter-Ultra-Safe-Battery-Charger-Portable%2Fdp%2FB088K5D88K%2Fref%3Dmp_s_a_1_1_sspa%3Fdchild%3D1%26keywords%3D12%2Bvolt%2Bpower%2Bpack%26qid%3D1602341522%26sr%3D8-1-spons%26psc%3D1&qualifier=1602341522&id=3125572137240767&widgetName=sp_phone_search_atf

All i did was remove crocodile clips and fitted a plug for my mirror fan and later on i will make a lead for a dew heater when i get it 

looks very similar to the one i got 👍

1 minute ago, x6gas said:

Nice image Bobby.  On my monitor the background looks a bit black to me and I wonder if you've clipped the black point at some stage.

Cheers, Ian 

i think i have maybe clipped it a little, you are correct, im still fairly happy with it

4 minutes ago, happy-kat said:

Very nice

How long were the subs?

30s

While the AZGTI was doing its thing with my scope on the Pacman nebula i set the star adventurer going with my A57 and an old 50mm Minolta f1.7 lens @f2.5 in the Cygnus area. 

Captured around 1hr 8mins worth of 30s subs at 800iso, captured darks and flats also.

Stacked in DSS and processed in Startools, Topaz and paint.net

I think i have captured a few objects in this frame.

Thanks for looking

Annotated:-

4 minutes ago, Juicy6 said:

And what was the temp difference when you pushed vs pulled air over heatsink? You asked the question and you can tell us!

Christer, Sweden

I haven't tried swapping the fan around yet, i currently have it drawing ambient air onto the heatsink. 

1 minute ago, Tomatobro said:

If you lag the camera body then tuck the sensor next to the camera body underneath the insulation. Use sharpcap to monitor the sensor temperature and adjust the on/off controller temperature till it gives you what you want. These temperature settings will be different to what sharpcap says but once set will give good results.

Takes about a hour and a half of bench time to optimise the settings

Excellent, thanks so much for the info.  if i can get the thing to a steady 3-4deg regardless of the ambient and also stop the sensor window fogging up i will be more than happy.

Thanks again

Had a crack at this last night as its another target i haven't "seen" or captured in anyway previously.

So, this is 2hrs 40 mins worth of 180s subs from the ZWO 178MC, plus some darks i captured previously at a similar temp and some flats.

Processed in Startools, Topaz Denoise and Paint.Net

Not as good as many others but for the effort i put in along with my meagre processing "skills" i'm not too unhappy with this one.

Thanks for looking 🙂

3 minutes ago, Tomatobro said:

comes with a remote sensor. The relay is rated at 10 amps and comes with a set of instructions on set up options.

Is it best to sandwich the remote sensor on the cold side of the Peltier?

Or just somewhere on the case of the camera??

Thanks again, all good info and an exciting DIY project

12 minutes ago, Tomatobro said:

I use these modules a lot from Ebay

 

193288386461

Under a fiver

Even comes in a self assembly clear case

Thats a bargain. 

does it require a sensor adding to the case of the camera/peltier? Or does it just measure ambient??

Thanks again

3 minutes ago, Tomatobro said:

Re the temperature drop question,  in a warm room at say 20c and bench testing shows a sensor temperature of 5 c means that outside in the cold air it will go down to around -8c unless some form of control is introduced.

when i bench tested it yesterday, it was in my cool garage, probably around 12-14 deg.

I do appreciate what you are saying and if needed will introduce some sort of temp control to the system.

I used the jump start battery pack last night and i had an issue.

Although it powered up my ASIAir and AZgti (via the ASIAir) the mount itself would not respond to slew commands or gotos etc.

It is definatley delivering 12v as it powers other equipment such as the 12v cooler mod i am working on for my camera.

When i replaced the battery pack with my old car battery the ASIAIr and AZGTI worked just fine. 

The jump starter states 12v/10a on it so i am a little perplexed as to why it wouldn't run the ASIAir and AZGti just as my old car battery does.

28 minutes ago, tomato said:

I can confirm that the ZWO heater fits the ASI 178 mono.

https://www.firstlightoptics.com/zwo-accessories/zwo-anti-dew-heater-strip-for-asi-cooled-cameras.html
 

As the non cooled cameras aren’t designed with forced cooling in mind, they can be prone to  ice crystals and water droplets. I recommend not taking the temp sub zero but rather keeping it stable at 2-3 degrees, thereby ensuring consistent application of calibration frames.

That is awesome news, many thanks for confirming, i was about to start cutting out circular bits of paper/card to check if it would work lol.

I have no intention of running it sub zero, i don't think it will get there anyway tbh, seems to level off at around 3-4 deg.

Just need some suitable insulation to make a jacket for it now.

Thanks again

Not 100% sure the Zwo dew strip will fit the 178mc. 

I wonder, would a camera lens dew heater, wrapped around the part of the focusser where the nosepiece of the camera inserts, work maybe? 

Ultimately the front part of the camera needs to be kept a bit "warmer" than the rest of the camera, right? Or have I got this all wrong?

So. The replacement peltier arrived today.

I have literally just cobbled this together for some testing. 

Anyway I left it running for 10-15mins. Temp down to 3.5 degrees. So pretty good I think. 

However, the sensor window fogged up :-(. And there was some moisture on outside of the camera.camera 😞

So, my next query is, what can I do to stop the foggiing up and the moisture build up ? 

Really pleased at the performance of the cooler itself. Just another couple of issues to fix now. 😡

Wonder if I can make one of these fit:-

https://www.firstlightoptics.com/zwo-accessories/zwo-anti-dew-heater-strip-for-asi-cooled-cameras.html

4 minutes ago, teoria_del_big_bang said:

Its okay I have seen it now in the title says 22000 mAhrs so 22 A/hrs. 

I need to check what my setup pulls but if I don't so too much slewing of mount I would guess about 5A, so I would get around 4 hours. So not bad for that price. Might need 2 of them though 🙂 

Steve

I did wonder if I was seeing things that weren't there. Lol

I also have an old car battery and a 7ah leisure battery. Hopefully I now have enough "juice" for my AsiAir, AZGti and cams along with a home made peltier cooler for my 178mc. As you say, cam always get another as the price is very good. You don't get a wall plug with it tho. It comes with a usb cable (usb c input) for charging but you probably have an old phone charger or something you can use ??

I had intended on getting the 17ah Skywatcher power tank. But the Amazon one is definitely better value and lithium Ion rather than lead acid. 

26 minutes ago, teoria_del_big_bang said:

I cannot find any reference on the Amazon listing to Ampere/hours is there anything in the documentation you got with it, so I have no way of working out how long it would last on my setup. 

Steve

How many amps does your set up pull in total?

I can have a look tomorrow at the paperwork  as it's in the garage. Comes with a nice case too. 

12 minutes ago, GordonD said:

Wow 22Ah for 70 quid is bit of a bargain!

Yep. Seems really well built and it's lithium ion. And has usb ports as well as 12v out via the 2.1mm DC socket or can use a 12v car socket adaptor which comes with it. Built in torch too. I intend on sticking some red gel over it for better night use. 

I've just got one of these:-

https://www.amazon.co.uk/dp/B07WG1JVYJ/ref=cm_sw_r_cp_apa_i_Z51FFb7EP7YY3

Not used it yet but seems well built and 22amps should be more than enough, hopefully. 

I am still waiting on a Peltier cooler. Got most of the bits now. But the pletier arrived with one of the wires hanging off. So it's been returned. 

Hope to have something cobbled together at the weekend. 

I'm not expecting it to perform as a cooled camera would. But from the you tube videos it would seem a reasonable improvement in terms of noise in images can be had. Fingers crossed. 

Thanks for all of the replies. I hope I haven't opened a can of worms here lol

Seems as though pulling ambient air into the heatsink is the best way to go. 

19 minutes ago, Xplode said:

It's usually best to blow the cold air at the object that needs to be cooled, this is how, this is how 99% of all computers are setup

So that would be sucking the ambient air onto and across the heatsink???