Erling G-P

For my HEQ5Pro, I've had to set the polar scope illumination to a minimum level - otherwise it drowns out Polaris. After getting an angle finder, I've had to up the illumination if I use the magnification, as it turns the image much darker. As suggested by others, I would make sure nothing is blocking the view - counterweight bar and axis - and of course lens cap. You say you can see a dot on the wall at home through the polar scope. If it's in focus, it suggests that the scope is focused on close objects, and that something at infinity might not be ? Regards, Erling G-P

I have the same scope & mount, and have had problems too, with a fairly heavy DSLR attached (and putting a heavy ADM saddle on didn't help either). One neat trick that does help however, is rotating the OTA so that the eyepiece or camera is on the 'inside', towards the mount - that moves the center of gravity closer to the mount and was enough to solve the problem in my case. Cheers, Erling G-P

Hi Alex, I have a 200PDS and a recently acquired 130PDS which hasn't seen first light yet due to I use Skywatcher's 0.9 Coma corrector / reducer, having fitted it to the camera with an M48 t-ring like you. After that I just plop the coma corrector (with camera attached) into the focuser, instead of an eyepiece. Haven't used filters yet, so not sure where to place that - front or back of coma corrector perhaps?

There is And to Eikie: yes, 6 has to be at the bottom & 12 at the top, like a clock dial, as accurately as you can make it. Like others, I can recommend the app SynscanInit2. It provides you with a graphical representation of what you should see in the polar scope - has made my PA more accurate, than when I had to figure out myself where on the clock dial I should put Polaris, based on the time given by the hand control. In addition to dimming the light in the polar scope, remember also to extract the counter weight bar & turn the Dec. axis 90º - otherwise the view will be blocked (But you probably know this, if you've zeroed the scope in daylight) Best of luck, Erling

Hi Asim, Thanks for your kind words regarding my images; I'm still just a beginner, fumbling my way around, having done this for about a year now. Yes, images were tracked, but not guided. I'm trying to get guiding up and running, as I'm pretty much restricted to 30-sec exposures as it is now - trying to increase the exposure times results in too many lost subs, due to tracking errors (A HEQ5Pro is probably at its limit with a 200PDS). I'm blessed with having Bortle 4 skies where I live, so all shots were from my garden. With regards to processing, I'm very much experimenting, still learning. All has been done with Astroart 6, and Andromeda wasn't particularly hard. It has a filter called 'DDP', which is described as 'making digital look like film'. I find it invaluable for galaxies, as it makes for a smooth transition from the core to the fainter outer parts. Don't know if it goes under different names in other image softwares. Andromeda pic was made by using 219 out of 250 subs, each 30-sec, so total time is 109.5 minutes to be exact. Stacked with DeepSky Stacker. Used 20 darks and no flats. Images shot at ISO 200. In your case, I would go for a CC first, and then look at guiding, but remember that I'm just a beginner, so take it with a pinch of salt As mentioned, I'm trying to get guiding working myself. Have the necessary hardware ready, but weather has been most uncooperative the entire autumn. Also have a new (to me) astro modded, cooled Canon DSLR, that I'm dying to try, but the weather.. Best of luck with your continued endevors, Erling

It is indeed. I have a Skywatcher 200PDS (8" Newton), using it unguided so far on a HEQ5Pro, with a Nikon D7000. Like you I have also found M57 to be very small, and have tried a couple of times to use a 2x Barlow. Shooting unguided, I have limited myself to 30-sec exposures, but with the Barlow, I had to discard them all, due to tracking errors being blown up. Finally got something somewhat useful, by going down to 15-sec exposures. Below are two cropped versions of this; the first have used less subs, while I included more, lower quality ones for the 2nd. As you can see, the 2nd perhaps looks nicer regarding the nebula, but is definitely more fuzzy. Reason for the smaller central star, is using 'Reduce stars' feature of Astroart.

I have the same scope as you, and am using Skywatcher's 0.9 reducer/CC. I have never used the scope for imaging without it, so can't offer any with/without comparisons. One advantage of this CC is that it will work with other scopes too - a 130PDS for example. Got such one a couple of months ago, for wider field work, but regrettably weather hasn't permitted me to use it even once yet. Below are some shots with the 200PDS, on an unguided HEQ5Pro, using a Nikon D7000, with 30-sec exposures stacked, so a setup very similar to your own:

I guess so, although there's some pretty big jumps between them. Another limitation is that you can program two separate sequences, each of up to 50 pictures. In other words, 100 pics is the most you can program in one go, if you use both sequences. With my short exposures and the Nikon, I've typically shot at least twice that, but once I get guiding to work, I should be able to increase the exposure times, thus needing fewer subs, and then 100 may be more than enough. Alternatively, you could of course just restart the sequences as many times as necessary.

Thanks for the reply and the links David. The smaller power supply appears fixed at 13.8V, which would make it a no go for me. I had seen other supplies fixed at this specific voltage, and asked Primalucelab if that would be ok for the cooling, but they warned I might ruin it if I went beyond 12V, so don't dare do this. Without knowing how much of a voltage drop I might see if I use a long cable, it would be a bit of a gamble. Like you say, there seems to be many different ways to do this, so I have some thinking to do. Adding to the complexity, the supplied power cable for the camera has banana plugs in the supply end, and the socket in the cooling unit is incompatible with the kind of power cables I use for my mount & the Synguider - looks like the same kind, but the center pin is a little bit thicker. Thus I may have to modify the supplied one.

Thanks for the replies. With a history of several hernia operations behind me, I'm trying to avoid heavy lifts as much as possible, so 20kg batteries would not be a wise solution. Thus leaning towards something mains connected. David, is it correctly assumed that you keep your power supply indoors, and then run a long, low voltage cable to your equipment ? Regards, Erling G-P

Thanks everyone for the replies. I had read about the mirror lock in the manual, but never pictured it working with an intervalometer. With regards to using a laptop; that's what I'm currently trying to avoid, preferring the simpler standalone option of a DSLR. Primalucelab has actually built an intervalometer into the cooling system. It requires running a small, supplied cable from the cooler to the camera's external controller socket, and is fairly simple, with fixed exposure times of 1, 5, 10, 30, 60, 120, 180, 300, 600 or 900 secs. It of course requires the cooling system to be running, so in case of using the camera without that, an alternative would be nice - perhaps also to have greater flexibility with regards to exposure times. I do recall reading about Magic Lantern quite a while ago, but had forgotten about it. It definitely sounds like something to get. Regards, Erling G-P

Hello all, Have just acquired a 2nd hand Primalucelab Canon 700Da (cooled). Had originally imagined I would power it with the Skywatcher 17Ah Powertank I use for my HEQ5 (and intend to use for the Synguider 2 I'm trying to get up and running) Got worried by the manual stating that the cooling requires a 12V 5A power supply - that seemed like a lot of current. Set about measuring it with my multimeter, using my Powertank. Showed a current draw of 3.6A. I let it run until it reached the set temperature of -5ºC, wanting to see if the high current draw was only during the initial cooling to reach the desired temperature. While it did start to fluctuate a bit, along with the fan speed, it did seem to hower around 3A. At this point I realized it had almost melted the wires for my multimeter! They were glowing hot and completely soft, so terminated the experiment immediately. With the high power consumption, I'm worried my powertank will be drained in a few hours, if I use it for the camera. As mentioned above, I'm also trying to start guiding, and have been told this will considerably increase the power consumption of my mount, adding to the problem. Presently, I'm imaging from my garden, so do have access to mains power. Have asked Primaluce for a recommendation, and they suggested a heavy duty car battery for powering everything. Not too keen on having to haul a heavy car battery back & forth in each session however. Also asked 365Astronomy who sold the camera originally. They suggested using my Powertank, stating to have used just such one for such a camera. Figure the cooling must work on the same principle in other cooled cameras, so expect them all to have high power demands, and so wondering; what do you guys with cooled cameras use to power them ? Thanks in advance for any answers. Regards, Erling G-P

Hello all, Have been imaging for about a year. So far I've used my bog standard Nikon D7000, but have now acquired a Canon 700D, astromodded & cooled, by Primalucelab. On the Nikon, I've had good use of some of its more obscure features, more specifically these: 1. Intervalometer. With this I've programmed my sequences of images. Limits me to exposure settings available on the camera, so 30 secs is the longest subs I can make. With an unguided 200PDS on a HEQ5 Pro, short exposures have been necesssary however - my attempts at longer ones via an external controller have resulted in too many discarded frames. 2. Delayed shutter release. With this, the camera flips the mirror and then waits a second before opening the shutter, to prevent vibrations from affecting the image. 3. Quiet release. Dampens the noise of the mirror & shutter, making it more discrete. I've assumed it might dampen vibrations further, and if it makes the camera clicking away in the garden less aurally conspicuous to passers by, then all the better. I have browsed through all the menus on the Canon, and also looked in the manual, but can't find anything resembling the above features. Puzzles me, as with Canon & Nikon being competitors, I would expect them to offer more or less the same features. Can anyone familiar with the 700D tell me if it doesn't have similar features, or if it's just me who can't find them ? I hasten to add that this is in no way, shape or form intended to become a Nikon vs. Canon mudslinging contest. Each camera respectively is my first of either mark, and I have no preferences presently Regards, Erling G-P

Thanks; it seems to be. Weather hasn't been cooperative, so haven't had a chance to try it yet. Also have been caught by surprise by the high power consumption by the cooling system, and have yet to work out how I'm going to power it. Regards, Erling G-P

Camera is sold WonderStar; I bought it. Don't know why Annie hasn't updated this thread. She went completely silent after I received the camera, and hasn't responded to any of my follow up messages. Regards, Erling G-P