![]() I have not tested whether this means that with a 50mm lens you can do 100 seconds. 25 seconds at 200mm means you can get away with 50 seconds at 100mm. "Field rotation makes it completely useless" is wrong. But maybe the newer image processing software that I am not familiar with can handle it. The benefit is much less work at the image processing side when you get back home and want to turn those frames into an image. It's not much more than having to learn the buttons on a new photocopier, microwave, or TV remote when you change cable fibre. Yes, the equatorial means a rotating camera that starts and ends at different angles, and is more complicated than a simple up-down-left-right unit, but that learning curve is short and actually pretty easy. Sure, I can "get away" with it for some things, but for the same price you can purchase an equatorial unit. With all the success I managed here, you might be surprised with that. So would I recommend the iOptron? Short answer: definitive NO. Pluto is way down low in Sagittarius, so it is not surprising that I did not quite reach its mag 14.4 glowing speck through the suburban glow and forest fire smoke. Using only the iOptron's goto function to get to Pluto, it put me on the right field within 1/4 of the width, while I was at 200mm focal length. You actually need more than 10 times the half minute to get as good a signal to noise ratio than a single 5 minute one. 25 seconds is a low signal - in Skynews many people take subframes of 5 minutes for a good signal. The concept of stacking is to add signal while the noise averages itself out. I was able to do this with ImagesPlus software, but (with my older v5.5) I had to manually click on two stars for each image so the software could recognize the rotation. ![]() One shortcut to step around the problem is to take short exposures that do not reveal the trail, in my case 25 seconds at 200mm, then later in software, stack the images by compensating for the rotation from one frame to the next. Visually, who cares if things rotate 15 degrees in an observing session? Photographically it matters. All professional telescopes have "de-rotators" that turn the camera/sensor at just the right rate to cancel it out. It shows up when an AltAz (Altitude-Azimuth) mount track in a diagonal line but the sky rotates around the poles (see parallactic angle). ![]() Quite disappointing (unacceptable?) for a beginner of 1 month experience I would think. You can see the stars towards the edges are all short circular arcs around the center of the image. Similarly with Messier objects and NGCs: just move the cursor over to the 0 and input the number. At first I was put out that Deneb was 75 button pushes of 170, but then I realized you could type in "075 ENTER" and bam there it was. I could choose named star or Messier or NGC object with a couple of short jumps down the menus. Pretty easy if you don't kick the tripod! Next object I went to was less than a 1/4 field from center, and so it was for the rest of the night. I then went to "SYNC to target", pressed the arrows to center it, then ENTER. I chose Vega and it showed up less than 1/3 of a field of view from center of a 135mm telephoto lens. ![]() You point the arrow south, turn your scope straight up (use a level lying across the dew shield), press ENTER a few times to accept GPS values, and you're ready to "Select and slew". Although you can manage without GPS by manually entering all the specifics, having the mount lock in makes everything easier. Newer Alt-Az units (the model we have has been discontinued) undoubtedly take less time to acquire a GPS signal. As you can see in the photo, the easiest way is to use a construction bubble level in two directions rather than use the little circular bubble on the side of the mount. The mount found the first star 40 minutes after starting, though I could have saved 11 minutes by turning on the GPS right away to register satellites while levelling the unit. Having the 5 minute demo from Luca earlier in the day, I assembled it at a neighbourhood park, literally a few metres from a streetlight, which is not a bad idea for a first assembly so you can see what you're doing. The tripod is similarly robust at 17.2 lbs (7.8 kg). The carrying case is 28.4 lbs (12.9kg), of which 10lbs (4.2kg) is the counterweight (important for balancing telescopes and camera lenses to prevent grinding the drive gears). The cube is a beefy unit, a tad smaller and lighter than a car battery.
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