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Is this RDF defective?

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13 replies to this topic

#1 ppbb

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Posted 16 January 2020 - 02:16 PM

I just got my Baader SkySurfer III.
I am concerned that it's defective. I can't see the red dot by looking straight thought it. I need to look "from above" (see pics). Is this one defective? It's my first RDF.

3271d9e521ad40e69faf9b4badaf7d70.jpg

93535981dc27bf0caf9bf02d0de93526.jpg

#2 JohnBear

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Posted 16 January 2020 - 02:27 PM

Most RDFs have Left-Right & Up-Down adjustments. If you haven't already, check that. Otherwise if this is the best you can get from it, I'd return it.


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#3 Jim Waters

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Posted 16 January 2020 - 02:38 PM

Check the battery.



#4 gkarris

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Posted 16 January 2020 - 02:40 PM

Most RDFs have Left-Right & Up-Down adjustments. If you haven't already, check that. Otherwise if this is the best you can get from it, I'd return it.

this...


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#5 vtornado

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Posted 16 January 2020 - 02:52 PM

Hello and welcome to CN

 

Venus is up in the early evening and the moon is up in the early morning.

Put the RDF on your scope, and try with one of these targets, because they are easy to find.

With a reflex finder like this.  Keep both eyes open while siting.

Use your highest focal length eyepiece (lowest power)

 

If after adjusting  the brightness, and adjustment screws on the RDF, if you can't see the dot,

or if the dot is on the target, but your scope is no where near it, then return it.

 

VT



#6 wtd1114

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Posted 16 January 2020 - 02:56 PM

The bottom picture is what I would expect from a red dot finder, so it looks like it works.  You don't put your eyes up to it and look through it like a conventional finder scope.  Your head needs to be about a foot or so behind the red dot finder and you need to have both eyes open.  You need to focus your eyes at the sky (infinity), move your head around to get it until you see the red dot "floating" in the sky.  The red dot is superimposed on the transparent screen.  Just like your last photo.   Once you see the red dot "floating" in the sky, the object behind the dot is where you are suppose to be pointed.

 

Initially, you need to calibrated it to your scope.  In daylight, you look at a phone pole or mountain far away through your scope.  You check your red dot to see what is  pointing to.  If it is not pointing to the same object in your scope, you need to turn the left-right knobs and up-down knobs to get it to align with the object you see in your scope.  One you do the calibration, the next time you look through the red dot finder, it should be at what you see in the scope.

 

Best-

 

Willis



#7 ppbb

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Posted 16 January 2020 - 03:05 PM

Yes, there is the dot but my concern is its placement. I'd expect to see the dot at the center of the circle seen on the first picture. Looking other way seems counterintuitive. And when I look "from above" the body obstructs part of the view.

Edited by ppbb, 16 January 2020 - 03:08 PM.

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#8 Jon Isaacs

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Posted 16 January 2020 - 03:52 PM

Yes, there is the dot but my concern is its placement. I'd expect to see the dot at the center of the circle seen on the first picture. Looking other way seems counterintuitive. And when I look "from above" the body obstructs part of the view.

 I believe the second picture showing the red dot is correct.  The dot should pretty much be aligned so it seems like you are looking straight ahead.

 

93535981dc27bf0caf9bf02d0de93526.jpg

 

These are reflex finders.  They do not actually project a beam.  Rather, you are looking down into the device at the reticule. The window serves as partial mirror. 

 

https://www.wikiwand...n/Red_dot_sight

 

Jon



#9 ppbb

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Posted 16 January 2020 - 04:29 PM

Most RDFs have Left-Right & Up-Down adjustments. If you haven't already, check that. Otherwise if this is the best you can get from it, I'd return it.


It indeed has these adjustments. They move the whole body against the base so this doesn't change anything with regards to the dot placement.

#10 ppbb

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Posted 16 January 2020 - 05:24 PM

I'm after the field test. I was able to align the center of the finder with the view from the eyepiece. But no amount of turning adjustment knobs aligned the dot to match with the EP.

Edited by ppbb, 16 January 2020 - 05:25 PM.


#11 Jon Isaacs

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Posted 17 January 2020 - 01:46 AM

I'm after the field test. I was able to align the center of the finder with the view from the eyepiece. But no amount of turning adjustment knobs aligned the dot to match with the EP.

 

That's not uncommon. With inexpensive red dots, I am often unable to align the dot with the eyepiece.

 

You are looking through the finder in the direction shown in the photo I posted?

 

What scope is this for? It looks like nice woodworking. Telrads are only about $40..

 

Jon



#12 ppbb

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Posted 17 January 2020 - 04:31 AM

 

You are looking through the finder in the direction shown in the photo I posted?

Which photo? You only posted one of my own. That is the direction I look from (the second one).

 

 

What scope is this for? It looks like nice woodworking. Telrads are only about $40..

I intend to use this on my APM 20x70 binoculars. So Telrad would be impractical.

 

And the nice woodworking is this. :grin:  I only put the RDF there just to take the photos.


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#13 Andynator

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Posted 17 January 2020 - 10:12 AM

Defective, no.

Off-centered, yes.

#14 NMBob

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Posted 17 January 2020 - 07:19 PM

Yes, there is the dot but my concern is its placement. I'd expect to see the dot at the center of the circle seen on the first picture. Looking other way seems counterintuitive. And when I look "from above" the body obstructs part of the view.

Yup, I'd send it back. The adjustments are to align it with the scope and not with itself. I had one from AgenaAstro that was so far off you couldn't get the dot anywhere near the center. Boy did they argue with me. Got a refund. :)




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