Red Dot finder help...

[malnuman]

hi all,   here is my 1st of what wil prob be many total newbie questions,    its regarding the Red Dot finder I got with my Heritage 130p.. having had bad weather past two nights, I havnt been able to make use of my scope yet,  but how does the Red dot finder work?  when I switch it on I cant see anything, is there meant to be a light shining out or something?   I put a new battery in but still nothing... also is the standard 10mm and 25mm lens that came with it any good?   I have ordered a 2x deluxe barlow is this a separate lens or do I use it with the 10mm & 25m?   thanks

[PeterCPC]

When you have switched the red dot finder on you look along the tube through the RDF and you will see a red dot at the end of the tube - you use this against the sky to align the scope with the intended target. Make sure that it is aligned with the scope first by adjusting it - do it during the day on a distant object but NOT the Sun.

Peter

[billyharris72]

Hi there, and welcome. Good scope you have there. I had the same issue with the RDF - it does take a bit of getting used to at first.

There are two things to bear in mind:

• The finder is designed in such a way that you have to look through the finder at just the right angle or you won't see the dot. This is needed to avoid the effect of parallax - if you could look into it from a range of angles it would point at different places depending on where your head was.
• The dot is not very bright in daylight, so it is possible to miss if it is a bright day or if the brightness is not up full.

Try getting down right behind the RDF (with your chin almost resting on the scope) so that you are looking straight through, and experiment with different angles to see if you can get the dot visible. Try first with the curtains closed if you are having no joy. You might also try adjusting the vertical and horizonal alignment to see if that brings the dot into view. In a dark room you will often be able to see a faint reflection of the light (but not a dot) if it is not lined up right - at least then you know the finder is working. Also, sometimes you can pick up a faint red glow looking in from the other direction (won't help you align but will at least reassure you the light is on).

Once you have the dot in view, then try aligning the RDF with the scope, using a distant object.

As for the eyepieces, they are basic but reasonably good for bundled eyepieces. I would start out with them and not feel any pressure to upgrade unless you find they are limiting your use of the scope.

Best of luck.

Billy.

[laudropb]

Hi when you look through the red dot finder with both eyes open, you should see just that, a red dot. During day light you may have to turn it up full to see it. You align it to your scope in day light by looking at a distant object through your longest focal length eye piece. Try to find a chimney or other easily recognisable object that is about a mile away. Centre the object in the eyepiece and get it in sharp focus. Look through the finder with both eyes open and adjust the finder using the wheels at the side and underneath the finder until the red dot is on the object. Check through the eye piece and make any fine adjustments as necessary.

Repeat this with your shorter eye piece. You should then be able to put a night time star in the red dot and when you look through the eyepiece it should be visible.

the Barlow goes on to the telescope first and then the eyepiece into the Barlow.

[malnuman]

thanks all,  so I attach it to the side of the scope, turn it on and I should see a red dot on the mirror?   I will give it a go later  

Edited April 5, 2016 by malnuman
spelling

[PeterCPC]

No, not on the mirror. At the front of the RDF by looking through it from the back.

Peter

[malnuman]

DOH!  told you I am a total newbie,   thanks for the helpfull replies,  I will get the hang of it.........eventually!!   

[happy-kat]

There is a mount place on the telescope to attach the rdf.

[malnuman]

hi happy-kat   yeah I managed to find that,  just when I 1st got the scope I turned on the RDF (see I am learning)   I was expecting to see a light or something.. I will try out the suggestions above later and see If I get any joy

[BeerMe]

I know that in mine there was a small film of plastic separating the battery from the connector that must be removed for the battery to provide power but since you have replaced the battery, that doesn't seem to be the issue here.

I think your problem is as simple as not looking through the proper angle to see the dot being projected on the scope of the RDF.  There is a small raised part behind the lens at the part of the unit nearest you as you look from behind.  The laser that provides the dot is emitted from here and you should see that lighting up when it is switched on.

I'll try to get a photo of mine for you...

[BeerMe]

Hope that helps...I had to crop the pics a lot to get them small enough for the forum.

[malnuman]

Thanks for the pics and advice BeerMe,   and yeah I finally saw the red dot      my problem was that the battery cover is loose, and I had to stick some tape over it to make a firm connection with the battery.  I will have a go at aligning my RDF with the scope tomorrow during the day, then hopefully tomorrow night I shall set it up outside for the 1st time  and take a look at the night sky,  weather permitting!   

[andyb505]

On my 130p the RDF was not very easy to set up. I think because it is plastic it was very difficult to adjust to get it to work properly. You may end up having to put a thin piece of plastic or paper underneath it to get it to align properly.

[laudropb]

I recently purchased a ST 102 refractor which came with a red dot finder. Having read many negative reports I was surprised to find that the finder was relatively easy to use and quite accurate. It does help that this scope has a good FOV but I am quite happy using the finder.

[pjsmith_6198]

The 25mm and 10mm eyepieces that came with the scope are pretty solid and will do the job.   The 2x Barlow is a good investment giving you the equivalent of  12.5mm and 5mm eyepieces.   That will pretty much cover telescopes operating envelope.  You will have high, medium, and low power EP's.    To use the Barlow slide the eyepiece in the top and tighten the screw on the side  and  use the assembly like another eyepiece.

[Mak the Night]

The mass produced (probably) Synta RDF's are more robust than they appear and actually surprisingly accurate and easy to use. However, it's not unknown to receive a damaged or borked one with a Synta scope. I had a dodgy one with my 102mm Mak and I ended up buying an Orion equivalent 'EZ Finder II' as the X- axis adjustment didn't work properly. 

You can see the X & Y axis calibration controls marked here. These kind of sights can often be difficult to use when the scope is pointing at or near the zenith and the red LED is often a bit bright and makes it difficult to see faint stars. For finding planets and the Moon though they are superb.

The Sky-Watcher 25mm and 10mm MA (Modified Achromat) eyepieces are pretty decent for what they are.

To double the magnification of the eyepiece place it into your Barlow and then place the whole thing in the scope (as above), or more usually, put the Barlow in first then just place the eyepiece into it. 

The Sky-Watcher Deluxe Barlow is Synta made and identical to this Celestron one (above). These are quite decent achromatic Barlows and better than the 2x Celestron (GSO) Omni equivalent IMO. They differ also in the fact that you can remove the Barlow element by unthreading it (shown above), this is a feature often only on expensive Barlows. When the unthreaded element is threaded directly into an eyepiece it shortens the focal length by about 1.6x. Effectively turning your 10mm EP into a 6.25mm and your 25mm into a 15.6mm eyepiece. This gives you six eyepieces if you include the magnifications with the eyepiece placed conventionally in the Barlow!

 

Edited April 11, 2016 by Mak the Night

[malnuman]

thanks for the info and pics Mak,  really helped.. I still have not had set my RDF up or used my scope yet,  weather has been terrible past week or so,   nowt  but clouds and rain since I had my scope delivered :-(

[Mak the Night]

You're welcome. Setting up the reflex sight isn't difficult, but you will need a fairly decent day, daylight wise, to achieve it. laudropb's method (above) of setting it up is the easiest method. Just sight something in the distance, like a church steeple or even a TV aerial, with a low powered eyepiece in your telescope, centre it in the eyepiece, and set the red dot to be on that centre as well. A bit of trial and error and you should set it up easy enough. They are simple to use after being set up. Unless you change the X & Y settings on the RDF they should stay pretty much the same even when you take it off the scope at the end of a session.

It's always the same when you buy new gear, the weather goes bad! lol