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I have decided to buy a red-dot finder when I was finally fed up with not knowing which star the telescope is actually point at, due to my right-angled optical finder scope. Most of you probably know how confusing a view through a finder scope can be, especially when you are pointing at a rich star field with most bright stars being roughly the same brightness. This becomes an issue when you want to starhop to your destination and you choose fairly dim star as your starting point. This is no big issue with a simple straight-through optical finder, because you can align the star to a centre of a cross with both eyes open. However, this becomes a problem with right angled finder scope, due to the reasons I mentioned earlier. So, to get the initial star hopping alignment more easily, I decided to get myself something that would help me with that. Since using two optical finders seems idiotic, I thought that some kind of projection finder scope would be in order; two options came to mind – either getting a Telrad or Rigel finders, or getting a simple, though much cheaper, red-dot finder. Since I just wanted a simple solution, red-dot finder it was.

I have chosen the Baader Sky Surfer III finder, primarily due to its ability to regulate the brightness of the projected red spot, which seemed handy. When I finally got it, it has occurred to me that there might be a problem – I wanted to use the red-dot finder the same way I use my optical finder, and that is, removable with a simple turn of a screw (no literary pun intended). However, although the body of the finder could be mounted to a plastic mount with a typical Synta mounting end, there was no mounting shoe supplied with it, and since I wanted to use both red-dot and optical finder at the same time, I had to purchase a mounting shoe separately. Other mounting options were pretty much permanent ones, which is not really practical when you regularly transport your telescope.

When I got the red-dot finder finally set up on my telescope, I have noticed that the projected red-dot is not working perfectly when turning around the brightness adjusting on/off button. It was regularly working, and then not working. Even though I changed the battery, the problem persisted, so I was frustrated and ready to send the finder back to the supplier. And then I though, since it had cost me only the equivalent of some £9, I just thought „to hell with it“, and decided to try and fix the problem myself. As it eventually turned out, one of the cables inside the electronics was faulty, so after replacing it, the finder scope finally worked as it should have, although it did not give me any confidence in this finder’s build quality. Furthermore, there are no dustcovers for the finder, which means that you will occasionally have to remove the dust from the projection lens mechanically, or, as I did, make some dustcovers on your own.

After you finally get the red-dot set up and working, you should align it with your scope during the day, because, the adjusting screws for both axes work a bit awkwardly. You have to combine adjusting with your thumb with a screwdriver, which seems complicated enough, and now try to do that at night. Luckily, once you align it, it stays aligned quite well, and some occasional deviation from the alignment is no biggie, since the finder scope does not magnify, and is basically for rough alignment. So, setting it up, getting it to work and aligning are quite complicated processes, but once done, you are ready to go and basically no additional tweaks are needed.

I like the way the red-dot finder is easy to use – you just turn it on, align the projected dot with what you want, and turn it off again. Nice and easy. The combination of a red-dot finder and an optical finder is unstoppable, and using the two in tandem allowed me to find objects that were too complicated or confusing to find using the starhopping method.

Upsides

  • Simple to use, intuitive
  • Great in combination with an optical finder
  • Adjustable brightness of the projection dot
  • Battery life
  • Range of mounting options
  • Very cheap
  • Better than those plastic 30mm optical finders

Downsides

  • Poor build quality
  • Difficult to align
  • Difficult to set up
  • The plastic mount flexes a bit
  • No dust covers
  • Projected dot poorly visible in daylight

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Edited by assasincz
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