Enceladus Dan

Test Results are in, the box isn't complete and I have further issues. I have made a handset on a 1m cable as that was length of temp sensor cable (will extend when finally finished). now my buck/boost module overheats, so I need a small fan on the side of the handset. with the box empty at 22c I can get the inside air to 4.9c. I still haven't made a seal for the lid yet, this is because I realised I never left space for the data cable between the camera and the wall of the box. now I'm planning to make a new box. while I had this one almost finished, I thought I would test it while taking darks. 

when setting up the ambient temp was 15c and the box reached a low of 2.4c, by the time I started taking darks the temp had risen to 20c and after my tests it was 22c. I set Magic lantern to take a 300s dark frame every 10 mins. I tested if having the LCD screen open helps by having it open as my intended plan, then quickly open the box and close it, then check the data after further cooling. results as below. 

peltier was running at a current limit of 2.2A variable voltage between 7.5-8.5v

Time from cooling started (Sub Started)                           Box Temp at start and end of sub                    Camera Temp from EXIF Data

10mins                                                                               13c / 11.5c                                                         22c

20mins                                                                               10c / 9.4c                                                           19c

30mins                                                                               8.8c / 8.5c                                                          17c

40mins                                                                               8.1/ 7.9c                                                             15c

50mins                                                                               7.6c / 7.4c                                                           14c

60mins                                                                               7.4c / 7.3c                                                           13c

70mins                                                                               7.3c / 7.1c                                                           12c

Screen Closed

80mins                                                                               8.6c / 8c                                                              12c

90mins                                                                               7.8c / 7.8c                                                           13c

100mins                                                                             7.7c / 7.6c                                                           13c

110mins                                                                             7.6c / 7.5c                                                           13c

120mins                                                                             7.5c / 7.6c                                                           13c

130mins                                                                             7.6c / 7.6c                                                           13c

140 mins                                                                            7.6c / 7.7c                                                           13c

Dark Frame comparisons, first are the frames which lead me to want to make this box. on the 7th of July during a heat wave I tried to image the veil, the ambient was 20c at midnight and by 3am when I started my darks it was still 17c. this is my first and last dark frame from that night. the Dark frames when viewed on the DSLR or my PC photo app don't look as red, this is how they open in GIMP. not sure if it is how the data actually looks and other viewer's are applying something to reduce noise. (no idea) . this is a crop of the bottom left corner of each frame (worst corner) 

these are the frames from the cooling test, edited in exactly the same way as above in GIMP, no changes just the same crop of the bottom left corner. this is the 10min, 70min and 140min frames listed above. 

while not completely free of noise they are remarkably better than non cooled. if the night is cooler than 20c it can only be better than this. now its time to order more Aluminium and start the Mk2. 

Regards

Danny. 

The prototype mk2 is finished. With a 100mm x 70mm aluminium heatsink and a 120mm computer fan . I made a bracket that pulls the heatsink down onto the holes for the Arctic Alpine holes (had to elongate a bit) and also holds to fan onto the heatsink. 

first test with 2A at ambient 22.3c gave me a drop of about 14c to 8.5c

then at 2.5A it dropped fast but from 9.6c it then heated, so at 2.5A the heatsink cant disapate the heat fast enough   

Finally at 2.25A at ambient 21.5c it dropped about 16c to 5.7c. 

all tests were indoors at night, with no camera inside just the probe taking inside air temp. The box is not yet complete as i need to seal around the nosepiece (i just plugged it for the test) and i need to make sure the lid seals good. 

all in all im much happier with a 16c drop in ambient temp. It Might improve with  a better design at the heatsink than my bodge up from using old holes. With the added weight of a bigger heatsink and fan i decided to put the project box with controlls on a long lead and not on the back of the box. I might even take out the temp control for a simple temp display, as i was able to tweak the temp drop with current limit. 

thanks

Danny

On 11/08/2022 at 10:58, Stuart1971 said:

Great image 👍🏼
but just an FYI, you should not use dark flats and bias frames, just pick one or the other….👍🏼

Thanks, I did read that but as i never head of dark flats till recently. I took both at the time just incase I had read it wrong. I think the veil has beat me this year. By 1am when lights go out it moving over the meridian and behing my house. But soon orion is back, which is a favourite of mine. 

On 11/08/2022 at 10:46, dark knight said:

I like this a lot Danny, I just had my canon 6d astro modded by Andy too last week and received my l- enhance from RVO, as yet not had chance to get out and test so was a good to see what a difference it will make

The filter is like magic, only issue I had was trying to get the red channel off the left of the histogram. At 300s it was still clipped on the left. I'm waiting for this heat to die down as camera temps are soo high and images too noisy. I did reprocess this data in a trial of pix insight which made a big difference. 

Quick update. 

I have the parts and have constructed the cooler box. I ran a quick test, although I have not assembled the project box with buck/boost module or the temp controller. I just soldered some wires so I can test it first incase I need changes. 

1st it did cool, but not as I hoped. 26c ambient and 18c at the heatsink inside the box. The arctic alpine 12 co fan is not very good. It's so slow and doesn't seem to be moving much air. The outside heatsink was hot to the touch. So next step is a better fan and some frankinstien attachment. I have an old tower cooler in the loft with a 92mm fan (same as the arctic, but should be faster) 

2nd. The buck/boost module can be set with both voltage and current limits. But it limited the volts to keep current (as I thought but was hoping some kind of magic was happening inside) but I did see the volts increase as the peltier was working ( guessing the resistance change with temp change) 

So now it's a fan exchange, then a different heatsink if I need to. 

Regards

Danny. 

Quick update, my 2nd try at the veil nebula, in reality my 4th but I discounted the middle 2. One I managed 1 hour 40 mins of lights but in processing the background was very red and the veil was washed out. It turned out Sahara sand was blowing over, the next time it clouded over after my first two 5 min exposures. 
 

this is my latest attempt, 26x 300s at iso 1600 lights, 24x 300s darks, 20 x flats, 20 x dark flats and 50 x bias. It’s not as clear as I’d hoped with 2 hours 10 mins compared to my first 20 min try out. But I think it’s the heatwave in the uk. APT reported camera temps of 32-37c during the session. 
 

regards

Danny

7 hours ago, VectorQuantity said:

If it's only 1W then that's great, your peltier should have no problems.

I have just done 4x 300s darks indoors at ambient 18c. For ease I measured amps at the 12v input to the dummy battery lead which has a 12-24v to 8.4v convertor. The dc jack after the converter is so small and goes in the side of the battery. 

My battery was at 12.4v as not charged since Friday. The 4 subs drew 0.169, 0.168, 0.167 and 0.167A seems the hotter the less power which makes sense. So average power is 2.08w but this includes power used to step down. Under no load (cam off) it was using 0.01A /0.02w but I guess the more load more wastage. Guessing efficiency is no better than 80% camera draws 1.6w. If it's lower I guess it will equal out as with electronics cooler will use more. 

Still 2w or lower still good. I used 4w as a worst case in first calculations. 

2 minutes ago, VectorQuantity said:

Hi Danny,

PSU. Appears to be OK and it's a good price so not the end of the world if it turns out not to do the job.

You should indeed be able to use it to adjust the peltier heat pump to an optimal value.

here's a link to a more detaied description. https://www.aliexpress.com/item/4000197872662.html

 

Thanks, good to hear. I was hoping that’s the case to fine tweak power input to suit the need, rather than just run it on more power and waste energy maybe and have to use temp control switch as read its best not to keep switch on and off. PWM was ok but can use low cycle so thought I would avoid both. 
 

thanks for the help. Hopefully have a picture and some successful temps to show soon. 
danny 

1 hour ago, VectorQuantity said:

Do you know how much power your camera consumes?

Not sure but I have been using a dummy battery on a 12v3a ac adaptor till now. Just having made a 12v power box so I can go off grid to a bortle 4 site. I could put my multimeter inline and measure current used while doing some test long exposures. Then Average them out. 
 

I did find a post with someone who did lots of tests with a 700d and 30s Timelapse with screen off is 1w of usage. 

32 minutes ago, VectorQuantity said:

re: 2. You would expect the o/p voltage to stay at its set point unless it's in current limit, i.e. not to change until you reach a current draw of 4A. Do you have a part number/link to the psu and the peltier?

The buck boost module is this one. 

DollaTek ZK-4KX CNC DC Buck Boost Converter CC CV 0.5-30V 4A Power Module Adjustable Regulated https://amzn.eu/d/dMVOCbE

And the chosen peltier is a tec1-12704. 

On a side note I have disregarded the sensor temp for my bad image on friday gone. It was bugging me and darks were bright red which made me think temp. But seen another post and this is normal when opened in a programe (my case gimp) I popped sd card in my 600d and sure enough darks are actually dark and zoomed in sees the noise. My darks were at 32c as was my last 2 x 300 subs which were the best 2 as background was grey. I went to earlier sub at 32c before sensor peeked at 34c and the background was red. 

It turns out we had some saharan sand signals in the sky when I was imaging. Explains why my car looks like I've been in the Dakar rally. 

Thanks

Danny

10 hours ago, VectorQuantity said:

Hi Danny,

1. Apologies it's a bit ambiguous are you able to re-phrase the question?

2. Is it a buck convertor (step down) or a boost convertor (step-up)? It could theoretically be both but that's unlikely. The majority of output protected convertors will current limit at which point it appears as a constant current. You shouldn't be running at the current limit point, this exists to prevent destruction of the PSU and the attached load.

Thank you for the reply, 

1. Was for the equation to figure out the hot side temp. Where ((Pin + qc)xC/W)+Ambient. the Pin figure I was unsure if I use the Peltiers rated power 36w or power applied. I went back to overclockers and it would appear to be power applied, so In my case 22w (which is good to reduce heat I need to extract). 

2. The adjustable buck/boost I have found claims to be both while offering constant current. Max Amps is 4A and I intend to only use 2 amps. I hoped this would give me the 11v 2A supply that the Peltier data sheet states. I guess I could just get it and test on a 12v 21w brake light bulb which should draw 1.75 amps, then try and limit to 1A and see if voltage remains at 12v. 
 

3. is again going to be a buy and see, I can’t find any data showing the efficiency in c/w, so will be some trial and hopefully not error. 
 

im trying to work it all out before I buy any of the parts, but with not knowing the C/W or the Qc values, it’s going to be a best guess. But at least I will have fun experimenting. 
 

thanks

Danny

Interesting to see the comments in that topic on fan push and pull. I was debating pulling heat away in my drawings, not for the airflow but on the fact the hot air leaving the heat sink is directed back towards the hot side of the Peltier. By pulling its taken away from it and possibly even picking up some cold air radiating round from the cold side and drawing that through the heat sink. 
 

I like a good tinker, and will have fun with this. More so than my diy dew heaters I think. 
 

thanks danny. 

Thanks tomato I will search it up. I found an other video, Explains a bit more and dt is driven by the amps used. So I believe the volts will be of less concern if I get amps right. So the buck/boost should work, and I can play with settings t fine tune it to get the air in the box to 0 or just under. I’m only looking to keep sensor in single figures if I can. 
 

maybe it’s time to play and see what happens. 
 

the rs online has some clearer data sheets, the ones I found online were in let’s say broken Chinese English. 

Thanks I will have a look. 

Hello, 

a project I’ve had on my mind a while now is a cooler for my DSLR. After testing my car battery power box for 6hrs on Friday 17th June running a mini pc, 14” monitor, dslr power, guide scope, tracking motors and 3 dew heaters (not attached just running for a test) with good results as I still had 70% battery, however the images were not so good. The Ambient temp was still over 20c at midnight and APT was reporting sensor temp of 34c after 300s exposures. So now I think I need to get moving with the cooler. 

my plan is to adopt the cooler box idea from Gary Honis, but slightly deeper so my 600D screen can be open slightly. Allowing cold air to reach the warmest part of the camera. I do like the simplicity of the cold plate butted to the back of the camera like with  Martin Pyott, but think all round cooling with its own little ambient temp would be better. I have drawn up an idea to add a small plate, from the cold heat sink to the back of the camera. In an attempt to see if like a cold finger takes the sensor heat out to the Peltier, if this plate will take some heat from the back of the camera away to the cold circulating air or even to the cold heat sink. See if I can create the best of both. 

Not wanting to just copy parts from others I’ve seen, I wanted to look into and understand what I was doing. Im thinking of buying separate components rather than a kit, as most posts I have read indicate bigger heat sinks and fans are required. I have read up and watched videos from overclockers about Peltier and have managed to wrap my head around most of the technical details on how it all works, but I have a few questions for those who specialise in this area. 

After reading many data sheets, I finally realised adding more volts, amps or going to a bigger module was only using more power and not increasing the delta temp as the hot side was hotter. So I settled on a tec1-12704 at 11v 2A giving a -40c drop. Assuming the hot side is (Peltier power 36w + Qc (camera heat unknown) then multiply by heat sink C/W 0.5 (actual is unknown) and add ambient 20c) I’m looking at a guess of 40c on my hottest night. 

1. Peltier power - for the hot side, is it just the rated power 36w or the power used ie. 11 x 2 = 22w?

2. power supply - My limited knowledge from a past career in vehicle electrics 25 years ago, is telling me if I apply 11v with the module being 3 ohms will draw 3.6A. I found a buck/boost module that has constant current, but I don’t know if it somehow limits current or just alters the volts to keep Amps steady. 
 

3. Heat sink - thermal resistance? Overclockers said assume 0.5 if it’s unknown, I was looking at an arctic alpine 12 co 100w rated. Smaller and lighter than a tower cooler but bigger than the kit sink and fan. The website doesn’t give a C/W rating for this but a graph showing a 65w cpu running at 70c with this cooler, one of their larger tower cooler is rated at C/W0.8. Am I just over thinking this, as I can’t get my head round how at 0.8 I won’t even reach 10c, but on YouTube a setup with a 60mm heat sink and fan or a cooler from a 5v mini fridge has formed ice at the cold side. 

Any advice or experience welcome, especially on the Peltier power and power supply. For the heat sink, my gut is saying just do it, As the cpu cooler must be better. 
 

Thanks

Danny

I was tempted by the l-enhance as its cheaper, I did have to Google is hydrogen beta was needed for any DSO as I had no idea. Didnt have much luck with result but someone saying Hb is good for looking at comets. I decided on th extreme based on people's comments on how much  more light pollution  and moon light is cut by being narrower. 

I found the green channel so much cleaner than red or blue, probably the double amount of green pixels in the sensor, also the Oiii seems stronger than Ha. I don't know if this is the light source is stronger or where I only did astro mod not full spectrum that maybe some Ha is still blocked. Hopefully more data will clean up that red channel. 

I'm glad I chose the extreme, especially with the street lights on my road. I have access to a bortle 4 site only 10 miles away, but I'm working on a power box so I can use the mini pc I use, I have a laptop but it's a gaming one and battery lasts 40 mins with no lead. Also don't fancy a £1300 laptop being dropped or soaked in dew. 

Regards 

Danny

Thanks, this filter is going to be a big game changer when the moon is out. Money well spent in my eyes, I was looking at dedicated cams and found myself getting run away. If I go a bit further I can get this, then what If I go mono. Before I knew it in my head I had spent over £2000 on an asi294mm pro filters and a wheel. So I dailed it back and thought go slow and take the next step with the l-extreme for my dslr and even my asi462 for small DSO's. Enjoy what I have and make the most of it first, I've only been doing this 12 months and still have lots to learn. 

Eventually I'll take the leap into dedicated, be it colour or mono. This filter will still have a place in my setup for large objects that won't frame on sensors smaller than aps-c. It's that or a shorter OTA/refractor to get target on a smaller sensor. 

Regards 

Danny

My home location is Bortle 5 and the night sky quality is pretty good, when the evil led street lights go out at 1am. At this time of year it only leaves me with about 1 hour before the dawn sky comes. There are two of these lights one at the end of my garden, the other is 3 houses down, because of the slope of the ground it’s lower down and less of an issue. 

In comes my new tool, the L-Extreme. The plan is it will allow me to make more use of my clear skies from home while the lights are on or the moon is out. It always seems like the moon knows when the sky is clear and makes a special appearance just to make things more awkward. 

My test target was the veil nebula which at midnight should have been clearing my neighbours tree at 40 degrees. This was also going to be a good test for my 600d I have just had modified by Andy Ellis at Astronomiser. 

Clear outside predicted clear skies from midnight, so I was all prepped by 10:30 ready to drift align when the clouds clear. Typical British weather, never cleared till 01:20 am. Besides the clouds causing me issues, I had a glitch with APT. My first time using APT and after framing and focusing the veil with 30 second exposures (I knew it would be harder than no filter but didn’t expect this long just to see 52 Cygni for framing and focus). I then started to take increasingly longer exposures to bring out the nebula and histogram off the left. I reached 5 minutes and saw nothing……… confused I disconnected my 600d and checked the images on the camera lcd and sure enough there was the veil in as short as 2 mins. I settled on 4 mins to try and get the red channel off the left, green and blue were pretty good but red less so. 
 

I reconnected my camera to APT and ran the 4 min exposures at ISO1600. Due to the time wasted by clouds and APT seeming to be stuck with an image from 30secs, newer images were not updating to the APT screen. I only managed 7 x 4 min exposures before the sky was lit up. While packing up I took 4 darks, 15 x 1 sec flats and 15 x 1 second dark flats( another first, I never done these before but I read they are better than bias if your flats are 1 sec or more)

after all my issues I experienced with my first try with this filter, I am mega impressed. Only 28 mins of data and I have an image I could never have expected. While stacking in DSS the recommendations said I should have bias frames, I thought from what I read that dark flats replaced bias frames. If any one knows for sure let me know. Anyway here is what 28 minutes in a bortle 5 sky with 90% moon looks like. 

I can’t wait to actually get a whole night of data for this, when the weather and computer issues allow me. 
 

regards

Danny. 

On 09/04/2021 at 14:42, wsteel33 said:

Next on the DIY list are a power box (with power for the mount, camera, dew heaters and RPi: I have already made my own 12v power distribution box which sits on my EXOS2 "portable" mount) and a couple of auto focusers using the MyfocuserPro2 project on sourceforge (the parts are winging their way to me as I sit here). The savings bring that dedicated mono camera all the closer 😀.

Any advice from anyone who has made these projects very welcome (maybe it will help me avoid more silly errors) or ideas for other projects too.

Clear skies 💫

Did you manage to make a power box? 

I'm in the process of making one and my next project is the cooler like you made for my 600D. 

My idea is a box with a 12v 95ah agm leisure battery, my output requirements were:

Hp elitedesk 800 g2 Mini PC- 19.5v 3.3A 

Old laptop screen 12v 2A

Dew heaters and camera 12v 5A

Tracking motors 6v  <1A

Once finished I'm hoping to have an all in 1 box with a harness inside that I only have connect to the telescope. I have access to a bortle 4 site with SQM 21.3 but it's 3km away from any power, also good that nearest street lights are also 3km away. The led ones at the back of my garden cause me so much hassle. 

I just need to finish the lower part of the lid with some black perspex and mount the battery monitor, buck converter 12-6v, dual USB charger and a mouse mat. With the left over I will block in the back of the lcd panel as it let's out lots of light. 

The harness will have 3x usb 3 (dslr, guiding with the asi120mm and planetary with asi462) Tracking power, dew heaters and camera. All wrapped in a cable tidy. Hopefully I will leave the RA, Dec and ST4 cables in the harness too. 

So far with an old 68ah car battery I had in the shed it ran for 5 hours as it is, just the PC running PHD2 and APT and the screen. The battery monitor showed 12v 90% when I packed up. 

Regards 

Danny. 

Thanks for both replies,  good to know it should work. After Google search was worried I would get error message and not  e able to use the camera. But there was no specific answer for manual mode, I was hoping it would work just as if was an old m42 lens or telescope which don't have the electric functions for the camera to communicate with. 

I may dabble with attempting a fix, maybe after seeing what results I get first. I have heard of stopping down to increase sharpness, but no real experience with lens astrophotography as I only have the 18-55 kit lens.

Thanks again. 

Danny

Hello, 

I have found an EF 50mm f/1.8 ii lens cheap because its appature blades are stuck at f/1.8. It states the Optics are good and clear, the focus works only the blades are stuck so it's sold as spares or repair for £29 which if working would come to around £70. 

My question is, will my canon 600d accept the lens and allow me to use it in manual mode, or will it give me errors and not let me operate my camera. I'm hoping this will be a cheap widefield lens as I will only use it at f1.8 and in manual mode. 

Thanks for any responses 

Danny

This is my 8 year old daughters, She watched me with my entry above and wanted to take her own picture. you may disqualify as really both of us made this. I set up my Eos M3 to wifi control from my phone and she took 500 frames with an intervalometer app. i showed her what settings to use in PIPP, Registax as they were still set up from my image. and this is her image shes proud of. again please disqualify as a two person effort. 

Regards

Danny

This is my entry, taken on the 10th December 2021, taken at 1800 just before the moon set. i tried out my ASI462mc for this and being new i recorded in 8bit mode causing me issues with registax. i had to change the PIPP output from Tiff to Bmp to get it to work. im not sure if i lost any detail by not changing the bit rate but im happy with the outcome. 

33,000 frames were taken from the video and the best 3,000 were stacked in Registax, i had a play with the wavelet sliders not really knowing how they work just stopped when i was happy. 

Regards

Danny

I had a chat with FLO and the thought is, as others have stated these are cheap mounts and the fact I can track more than 45 seconds unguided is doing well. I asked about the worm drive going tight in the same spot each rotation means I can't adjust out all the backlash. 

The offer was I can send it back and they would tune it which is chargable service. for now I think my plan will be to plod on and try the 1 direction guiding. I could swap the worms but in my head it would create too much backlash in RA by the time I adjust out all the binding. Possibly could slip where so loose. 

I may look at just buying a worm drive online, I saw on teleskop-express.de they can do one shipped to UK for £55. 

Hopefully soon I can have a full night session and try some ling exposures as so far I've only practiced setting up my guiding system due to clouds. 

Regards

Danny

an entry for category 2, I have no idea if I was supposed to add the constellation lines or not. 

this was only 10 x 30 second frames and 5 x 30 second darks. stacked in DSS and just levels adjusted in gimp. 

Thanks

Danny