Telrad issue

[rob0971]

I have recently bought a telrad to go on my sct for rough alignment. The issue I have is that the reticule when looking through the glass is not sharp, in fact it looks as if it is doubled up. This makes it very hard to see anything let alone align it. Does anyone else have this issue & can it be "focused" to get a sharper image on the glass panel?

Cheers

Rob

[Tinker1947]

This double up of the circles happened when i was wearing glasses, removed the glasses and all was well, there are no adjustments for focusing......

[hobsey]

I also get this as a glasses wearer and have to remove them to view through it.

Another thing I found, if you are going straight from the eyepiece to the telrad, you have to let your eyes adjust then all becomes clearer.

[mitchelln]

I've found you have to be looking through it "straight". I resisted buying a riser for a long time, but one came up in the classfieds. Definitely makes it easier to look through straight and also much easier on the neck!

[rob0971]

I get the double reticule & I don't wear glasses! It seems as though something is not properly aligned. I have tried moving around to look straight through, but I get it wherever I look, day or night.

[callump]

I can't say I have ever noticed this problem, and I use my long distance glasses when viewing through it.

This is what my camera saw...

http://starlightnights.com/callump/wp-content/uploads/2014/05/IMG_0274_1260.jpg

/callump

[brantuk]

The Telrad is just plain perspex - so it can't be focused. But you do need to look through it at the correct angle - or rather no angle at all. It's a straight through view so you do need to get it centered and be in line with it when viewing. You might have an electrical problem if the reticule isn't sharp - it certainly shouldn't be doubled up. Check the reticule is mounted correctly in the grooves at the sides of the pane - you could also try sliding it out and turning it round to make sure it's assembled correctly. Hth

[LeeB]

a telrad works by bringing the reticule to focus at infinity to lose any paralax errors, all with shortsighted problems will need glasses on those with long sight glasses off off, if the image still won't focus the reticle lens distance is incorrect.

if the focus is out ( should'nt be as telrads have no adjustment)  you can check by moving your head from side to side, the projected target should remain stationary on a long distance object with no parallax. if it moves against the background the image is not at infinity

I make my own red dot/ finders and the telrad is not helped by using a poor lens, I think its plastic

[rob0971]

Thanks to everyone for there comments, much appreciated. Lee, the image does stay on target when my head moves side to side. The ghosting of the image on the screen is better the closer I get to it. So my next question is, how far away should your eye be? It looks best to me around 6 ".

[mashedpotatomountain]

had exactly the same issue when i first got mine. i thought i must have a faulty one,

until i tried taking a photo of the reticule with a camera and it was sharp as a tack...

it was then i realised how rubbish my eyesight has got...

[LeeB]

Thanks to everyone for there comments, much appreciated. Lee, the image does stay on target when my head moves side to side. The ghosting of the image on the screen is better the closer I get to it. So my next question is, how far away should your eye be? It looks best to me around 6 ".

It should'nt matter how far you eye is away, as the image is at infinity as you move away the size of the rings in relation to the background will not change (they will appear to grow in the screen) but at a point the image will not fit in the screen , however if you are starting to suffer from shortsightedness a telrad will look out of focus as you eye struggles to conpensate for infinity, as above try taking a photo and if its sharp its you eyes I'm afraid.

[rob0971]

Yep coming to that conclusion!

[uminded]

Adding to an old topic, this was the first google result.

The reason my telrad was fuzzy was dust from changing the batteries! I blew it out and wiped the lens and its sharp and defined.

[Charic]

Its the reason I sold my first Telrad, I needed to wear my glasses go see the rings clearly.

I honestly think there is nothing wrong with your Telrad, they are solid and quite durable.

I suggest your next move is to visit the opticians, be on the safe side.

Infact, just reading a thread this week, I may even have to get used to using my other eye at the eyepiece, as, on its own, my right eye is not so good.

Wish you luck.