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I have been trying, but completely failing, to copy the arrangement for viewing the sun mentioned on this website: https://astronomyconnect.com/forums/articles/2-three-ways-to-safely-observe-the-sun.21/ enter image description here

The telescope shown does not appear to have a finderscope or any other obvious means of finding/tracking the sun. This set up is actually far harder to do than it would appear in the photo. However, I think it is worth the effort as it doesn't risk blinding the observer.

Finding the sun is not our issue because our telescope moves. We punch in what we want to look at and the telescope moves there. We can use it manually, but have found that the sun is surprisingly difficult to find without looking through the finderscope. We are not willing to do that for obvious reasons.

I have been trying to figure out a way to have the board portion grab hold of our telescope instead of set on a table. So when the telescope moves, the board moves with it. Orion does sell a sun-filter, which I have purchased, but I am not willing to set a precedent with my homeschoolers where they look at the sun through the telescope - even with a sun filter.

Does anyone know of another website with instructions to use the telescope as a projector that uses a telescope similar to mine?

Our telescope

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Yes this is a bit more of a challenge! The first scope in the photo is long and thin and before the big square cardboard shadow-maker is put on it can be easily pointed at the Sun by moving the telescope until its shadow becomes a small circle, the minimum outline of the scope. If it's off a little bit that long tube's shadow will immediately change shape.

But with a short squat form factor your telescope won't be so easy. Start with the smallest magnification largest focal length eyepiece and at least try to use the shadow method of looking at the shadow that your telescope makes behind it (on something flat and held perpendicular to the Sun's direction, and move the scope around trying to make the most circular profile shadow. For this method, instead of a finder scope you can use an empty long thin tube to make a shadow.

Wait, you have a finder scope!

Eyepiece projection will work just as nicely for your finder scope as your main scope, so BEFORE you use it for the Sun, check that the finder is aligned to the main scope EITHER AT NIGHT or using TERESTRIAL OBJECTS on the ground. DON'T POINT IT AT THE SUN if there's any chance that you will look through it.

Those have to be distant objects so parallax doesn't lead to misalignment.

Once your finder scope is aligned to your main telescope, use eyepiece projection to get a nice centered image from it. At that point your main scope should be really close.

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  • $\begingroup$ So , if I understand you correctly, the projection should occur through the finderscope instead of the main telescope? In all my attempts, I had the finderscope capped off. I will try your "shadow aiming" trick our next sunny day. $\endgroup$
    – Bookaholic
    Nov 28, 2020 at 5:54
  • $\begingroup$ @Bookaholic not instead of but rather in addition to. The finder scope may have a field of view of perhaps 5 or 7 degrees roughly, while even at the lowest magnification your main telescope's field of view will be 10 times narrower. So even if your scope is off by many degrees eh finder scope will work as a projector, and then you can move around until the finder's projection is directly behind it, centered on the finder's own shadow. If you are careful and your finder is aligned, then you should already see some misaligned projection from your main scope. $\endgroup$
    – uhoh
    Nov 28, 2020 at 6:03
  • $\begingroup$ @Bookaholic You can practice a little bit using a bright light in a dark room, or a bright streetlight outside a window. Your finder scope will make a small projection of those as well. But once you focus it on the object by eye move the eyepiece outwards away the front lens so that it will focus not at infinity, but at a sheet of paper held nearby. It may take some practice but it may be more comfortable doing this first to gain experience. $\endgroup$
    – uhoh
    Nov 28, 2020 at 6:07
  • $\begingroup$ Other uses may post additional and more helpful answers as well, so continue to check back here regularly $\endgroup$
    – uhoh
    Nov 28, 2020 at 6:07
  • $\begingroup$ It might be possible to replicate the Baader Sky Surfer's solar finder functionality by making a small hole in the front lens cap of the finder scope and using a clear plastic rear lens cap to see the projected solar image. $\endgroup$
    – Aaron F
    Nov 28, 2020 at 11:34

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