tassie tiger

Seeing was very nice this morning (22nd Feb AEST)
I chose not to have the cooling system on all night as I have found it is getting too cold. When I got up at 4.30am, the mirror was still 1 degree above ambient. 20 minutes later, I had turned off the cooling system and was happily focussing.
This one was probably the pick of the evening, bordering on 8/10 seeing.

High cloud started to interfere a bit and dawn was approaching, but I did want to get the GRS peeking around the corner


Thanks for looking

Very cloudy this morning and at the end of the day I was not really worried about the quality of the image, just really some testing

I got my evaluation fully featured edition of Lucam Recorder by Astro Factum. It is one impressive piece of software. It allows for 12 bit saving of tiff or fits or sers straight to a directory that creates itself based on the UT time. There is also the capability of filter wheel capture.

To get 60 fps in 12 bit data, I had to record to memory, which was fine, but whilst it was fast to record 30s @ 60fps, it took the full 30s to write from memory to hard disk....................i feel I will have an issue with changing filters. For example 30 sec @ 60fps for red, wait another 30 seconds to dump, 30s # 60fps for green, 30 secs to dump, 30 s@60fps for blue, 30 s to dump. In total 150s from red to blue, which will probabley be a bit too long re rotation. The software writer of the program is very approachable, so it may be something He can fix.

Overall, very happy with the camera and software, can't wait to add the filter wheel.

"Cutting off your fingers....oops I mean cutting and drilling holes"


drilling the perspex, note the nylon nuts and bolts, to try and stop any "cold" transferring out of the system


4mm hole done


now for the aluminium


lets attach it up


take the aluminium off and cut out the holes with a jigsaw without cutting yourself!


attach up the aluminium again and don't forget to cut your toenails before showing them on the internet!

"Preparing the perspex"


already marked in the centre by the guy that cut the material with the band saw


always need some help...........


3 peltiers, therefore 360 divide 3 = 120 degrees separation. Need to make sure that there are spread out enough to evenly cool the plate.



this is the section that will be coming through the perspex and connecting to the aluminium round plate. The centre 4 holes are for attaching the unit to the aluminium plate



so, i will need to cut out these holes x 3

"Dismantling the Dick Smith Fridge"


Disassembling the cooling system from the body of the dick smith fridge.
Keep the 4 screws that connected the aluminium cold plate to the thin aluminium section


Extracting the overload


Getting the peltier module and fan out of the cooling system


Cutting the power leads


Peltier module is now extracted


Cutting the fan power leads


Unscrewing the fan


Fan and peltier module now

Last night the high cloud had gone away, but the seeing was not as good. I do now have officially a problem with the peltier cooling on nights when the overnight low is still warm. My usual procedure is to take the scope out, plug in 240 volt, on with the cooling and set the alarm.

The last couple of nights, the minimum temp has been arrived at well and truly by say 10pm (around 17 degrees). My cooling has kept chugging away and when I got up at 4.30am, the mirror was at 15.2, ambient 17.1!!! You beauty, inverted boundary layer problems. The actual detail was quite nice, but the shape was all over the shop.

It took about 1.5 hours for the mirror to warm back up. Birds automated cooling system is looking good!

It was nice during that 1.5 hours to observe the GRS pass around the corner and then the emergence of STrD-2.

I also got to play with the LU075M trying to check if I was actually capturing in 16 bit or 8 bit....time will tell i spose.

Filter wheels arrive tuesday

thanks again for looking

davo

I had both cameras out this morning. The lumenera and the toucam. Mick Pinner from melbourne has kindly offered to lend me his manual filter wheel to go with the LU075M from Bird. Top stuff guys, thanks heaps.

Seeing must have been good getting up near 7/10 at times. I was able to split antares to see its blue companion which is something i cant do very often with my 10" newt.

The high cloud cover had the ambient at least 1 degree higher than the cooled mirror, so it took at least 1/2 an hour to settle out. There remained a decent amount of tube currents even at 1/2 degree difference.

The colour captured toucam avi was split into BMPS and then ran though ppmcentre, for cropping and quality sorting. I then ran RGB split to break it up into the 3 channels to process through registax and astra image.

My best this year, but a long way to go!

Thanks for looking

Davo

Well my good friend Anthony Wesley (Bird) has kindly lent me his spare LU075M, so I got up this morning to give it a whirl. Thanks Bird, an awesome gesture and I intend to make sure "who goes around, comes around"
I downloaded the Lumenera drivers & program (LUCAM capture) and the capture program AMCAP. First thing I noticed is that you can preview and change settings in the lumenera program, but not capture avi's. In AMCAP, you can capture avi's but not change the settings. Apart from that, and the fact that I have a b/w camera but no filter wheels, I proceeded to have a go at Jupiter.

Upon inserting the LU075M at prime focus, it does not focus, so straight to the 5x powermate and 100mm extension tube. I assume the pixels are larger on this camera and as such, there has been a size reduction on the screen and hence capture.

60fps, well the computer handled it with ease which is very promising. The only issue was when the laptop found a wireless network and started asking me if I wanted to connect. Paul Haese will be wanting to push 100 fps with all that extra light available with his 18" mirror and I feel, that his new laptop should be equal to the task.

My first impression of 60 fps was the smoothness of the preview, but this is an illusion. When you capture at 5 fps, you notice the deformities easily, at 10 fps, the eye must smooth them out a bit and then at 60fps, the eye & brain think you are watching a super still object...ie it seems to blur.

So to try and determine seeing was hard from my first play with the LU075M. The resulting image is fair testiment to roughly 4/10. Once into registax and watching the optimise stage, I realised how bad the seeing was. The mirror and ambient had settled beautifully at 15 degrees C.

There was high level clouds which played havoc with the brightness even over the 20 and 30 second captures I was taking.

I intend to try 30fps over the weekend as I have been following Mike Salway's (Iceman) progress with his new 12" mirror and DMK. He is talking about the histogram, and I would like to test that I am getting proper dunamic ranges for different fps. Not sure if dynamic range will apply to a b/w image, but I will soon find out.

Now to the image, I am happy to have watched live the STrD disturbance that is just past the CM, but with b/w, I am unable to check the oval above it to check if it is red like BA.

For the future, i can see i will be needing to get a filter wheel..... once bitten with 30+ fps, I am now addicted! There is no practical way I can work with LRGB ie use the LU075M for 20s or 30s burst for Luminence and then take out the LU075M and replace with the toucam for RGB for a further 90 seconds. They have different focus points and I can see tears and frustration. PLUS, the resulting images are different sizes!!!

Thanks again Bird, i am not sure if I will now capture only in b/w or a bit of both....time will tell................Hey Darling Wife...if you really love me, a motorized filter wheel would be nice........

Thanks for looking

Davo

Got up this morning to a lovely clear sky. Fair bit of twinkle in the stars though. ESE winds do the seeing no good at all, as there are mountains and hills along the way. Any laminar flows from the ocean would be well and truly disrupted from this direction. I would rate the seeing at 4 or 5 out of 10. The GRS has paled significantly to last year. I still had 1/2 an hour until sunrise. The mirror temperature and ambient settled at 17 degrees which is very warm for my latitude.

Welcome to my BLOG.

I will be documenting my exploits at imaging the planets and also how I tinker with the equipment to try and maximise the experience of imaging.

Weather permitting, I hope to adding images here good and bad of Jupiter this season.

Thanks for looking

David Pretorius