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Compatible with the new ZWO ASiair
Combining the Sky-Watcher EvoGuide 50ED guidescope and the hugely popular ZWO ASI120MM-Mini lunar/planetary/guide camera.
The guidescope fits a standard Sky-Watcher / Celestron/ Orion finder-shoe.
This is a great bundle for the money. The scope is very high quality, all metal construction, with ED glass, and the camera is the perfect partner to it for guiding. This is my first guide scope and I was expecting a lot of hassle setting up the system. But the scope itself mounts very easily using the included Vixen dovetail plate and the camera does its job perfectly. Others have mentioned how far out of the focuser the camera needs to be to achieve focus, I found that this was nowhere near where I thought it was going to be. The camera has a small extender, about 15mm, attached to the barrel and that allows it to sit in the scope nicely so there's no issue. If you look at the image of the camera in the bundle and on its own, that extender is not in the images but it comes with the camera. So you can be confident that the camera won't be hanging on by its fingernails. Focusing on the scope is easy but takes time because it's a fine thread screw-type focuser so it takes time to get anywhere. You'll get it though. The camera on mine is positioned so there is about 4mm of the extender out of the scope. So camera, 4mm sensor cover (that's the black bit on the pics of the camera), and another 4mm of the extender. That allows perfect focus. Aligning the scope with the main OTA is easy using the screw adjusters in the scope rings. The screws have nylon tips so they don't damage the OTA. You do have to tighten them up though otherwise the scope could slip out in the rings. The lock nuts on the screw adjusters are great. That reminds me, I can't find a way of locking the focus on the scope. There is a screw that seems to be in the right place to do this but it doesn't seem to do anything when fully in or out.I'm very pleased with this bundle. It allowed me to set up effective guiding from zero to 300s test exposures of Andromeda the same evening it arrived.
The scope and camera arrived safely, and last Friday was a good option for testing them . All works great, but I was a bit surprised by how far the camera needs to stick out from the guidescope tube to get into focus: I had to put the the focus ring in its most extended position, and then I need to move the camera (with extension tube) up and down the shaft of the guidescope to find the focus position (it is then still several cm out from the normal position). But, it all works fine! When focused this way, setting it up with PHD2 worked within minutes, and I have been able to make photos of M57 with up to 10 min exposure with my SW NEQ6 without PEC, 200/1000 SW PDS, and EOS 600D camera using an H-alfa filter, without any obvious trailing! Only when the moon got out, the SNR became so low that PHD2 lost the star occasionally, indicating it was time to call it a night...
I've mounted this onto my SkyWatcher OTA, where it is a plug-in replacement for the existing finder scope (same base to the guidescope mount). I then used one of the supplied USB cables (there is a longer one and a shorter one in the box) to connect to my laptop. Then I loaded up the software from the ZWO website to provide drivers for the camera, as well as a camera viewer which allowed me to test it out. Since my first tests were in daylight I needed to adjust the exposure time to get anything other than a white over-exposed picture, but with a bit of fiddling it worked fine. When I tried it out at night, again I adjusted the exposure, and it picked out the moon and stars very well. Once I'd connected up my mount to the laptop as well (it's a Celestron CGEM mount and I needed a separate FTDI USB to Serial Adapater cable to do this), I was able to guide my shots using the free PHD2 software with only some very minor fiddling about, and capturing dark frames for PHD first. My first night's testing had rock solid 240s exposures, and I see no reason why I couldn't double this or more without any problem, but the moon was out so my subs would have been overexposed.
No. Unfortunately not. The Sky-Watcher EvoGuide 50ED will not work with a star-diagonal so is not suitable for use as a compact rich-field telescope.
First Light Optics LtdUnit 7 Budlake UnitsBudlake RoadMarsh Barton Trading EstateExeter, DevonEX2 8PY
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