Why is there still a market for magnified finderscopes?

[Jimtheslim]

This may seem like a simple question and there may be a straightforward answer. However I just can't understand why it's worth using a magnified finderscope or why there is still a market for them when you can just use a Telrad or similar. 

here's a summary of how I look for DSO's before and after buying a telrad:

With magnified finderscope - look at a star map and find the general area of sky. Spin the scope to the approximate area. Look for a bright star nearby and look through the finderscope and hope I'm in the right area and use it as a start. Then, get overwhelmingly confused by the increased number of stars in the finder compared to the naked eye and have no idea if I'm in the right place. Move the scope about and become more disoriented by the upside down and back to front movement. Look through the main eyepiece in the hope that the DSO just happens to be there, but be in constant doubt. Give up with the finder and just use a low mag ep.

With telrad - look at the telrad map and look for the most prominent star and it's position within the 3 rings. Look for that star in the sky. Turn the scope to the approximate position. Use both eyes from about a foot behind the telrad and using averted gaze put the star from the chart into the same place in the actual telrad rings. Look through the ep straight at the DSO and spend ages taking in the view and enjoying it. 

Using my telrad the other night was so easy and took all the doubt and frustration out of the search. I'm willing to bet i found targets faster than you could put them into a synscan type device and wait for it to move. 

My question is, why use a magnified finder when a Telrad or similar product is so much easier. I used to spend so much time going between the finder and the ep and having no idea if I was ever in the right place and often giving up. Given they are so much cheaper to make and buy, why are they not supplied with scopes as standard? Is it a bad thing, am I just lazy and not truly becoming familiar with navigating the night sky? Does it matter? 

 

[Stub Mandrel]

It depends what you are looking for. If you are trying to find Uranus or Neptune with a Telrad, good luck! Equally, my planetary imaging rig has a FOV of about 3.5 arc-minutes 1/8 the size of the Telrad's smallest circle, even with an x9 finder it has to be dead on and the target spot on the crosshairs to show on screen.

If you are looking for a bright planet with a scope or a sizeable DSO, very different although I can't say my RDF (not actually got a telrad) doesn't get a lot of use.

[Stu]

To be fair, I don’t use a finderscope much these days, but they can be handy for star hopping to a target. The wider field of view makes it easier to work out where you are, and the DSO in question may even be visible in the finderscope making centring it much easier.

So, I think it is as much about how you are using them as to whether you find them useful. Like many things, there is no right or wrong answer.

[Mr Spock]

Red dot finders are useless. Good luck finding anything faint!

I wouldn't have one given to me

[Davey-T]

It's hard enough finding stuff with a finder scope at 2500mm f/l when the little square formed by the double crosshairs in the finder is the same size as the FOV.

Dave

[CraigT82]

If you can't see many naked eye stars (ie. in the city) then reflex finders are not much use... You need a bit of light gathering to reveal dimmer stars to use for orientation/star hopping 

[John]

I use a combination of an optical finder and an illuminated reticule finder. Combined with a good star atlas and occasionally a wide field, low power eyepiece in the scope (to cover the final stages of the hunt for a particularly challenging object) I find these tools complement each other.

When I have to make do with just one form of finder I can manage with either optical or illuminated reticule but having both on the scope seems ideal to me.

[triton1]

Exactly what John said.

[johninderby]

Another vote for having both types on your scope. As mentioned it all depends on what you are looking at. Usually use the Telrad to get in the general,area then the 9x50 finder to zero in on what I want to look at. 

      John

[Louis D]

It depends on the focal length of your scope as well.  One of my setups has a 72ED with a 127 Mak on the other side.  A 40mm 70 degree eyepiece in the 72ED yields about a 6.5 degree true field of view which more or less negates any need of an optical finder.  I generally start with a green laser sight to get the scope swung to the general area then use a Rigel QuikFinder to get a more accurate centering.  I then look in the 72ED with a low power eyepiece to center it further and finally I can then look in the 127 Mak at a lower power to center it further since the two sides of the mount aren't quite exactly aligned.

For my Dob setups, they both have DSCs, so for difficult objects like Uranus and Neptune, I'll star align them with a Sky Commander unit prior to hunting them down.  I'll locate and realign on easy objects first to refine the initial two star alignment.  I just use a Telrad and green laser sights on them for initial targeting.

[Galen Gilmore]

It also depends on the quality of it, that might seem silly as you don't really think about the optical quality that much. But I have an excellent 6x26 finder that is a strait through correct image scope, and I use that more than I do my telrad. It is just the perfect size for star hopping, and the correct image really helps a lot.

[mikeDnight]

Finding and centering a planet in daylight needs a magnifying finder. Accurate alignment of a target at high power is easy with a magnifying finder without having to change to a lower power eyepiece to centre the object. Telrads are bug- ugly, cheap plastic contraptions that only belong on the ugliest of telescopes, hence the saying in this neck of the woods "That telescope's so ugly it makes a Telrad look good!" 

None of the above means that zero point finders are of no use. Some are very handy, but most are still ugly little blyters, with the exception of Televue's Starbeam, which with its wonderful flip mirror is a joy to use. However, they all need batteries, which optical finders don't.

 

[pi_co100]

I have a Telrad and I found little use for it from the skies I usually observe from. I suspect all of this is a matter of what you used to. My first telescope (a 114mm Newtonian) had a 6x30 finder  and from that time I just got used to have a magnified finder - except for the last couple of years when I do not use any finderscopes, as my mount just goes where it is supposed to (and calibrates with Platesolve)!

Piero

[nightfisher]

If i were looking for dso (i dont) i would prefer a combo, telrad and 9x50, but as the only thing i look at is Luna, planets and the odd double star, i find my 9x50 does the job just nice, say i want to look at mars i spot it in the sky, swing the scope till it appears in the finder, centre it and it should be in the field of the EP

[Jimtheslim]

I put my finder away in its box when I got my Telrad and it's never been back out. I suppose they could be good for star hopping to a target but that relies on starting in the right place in the first place which is what I found difficult, which is where using a combination of both comes in. I live in a semi rural area with mild light pollution and I guess I'm lucky in that all the stuff I've looked for so far have always had a star visible to the naked eye. 

I totally get that they are ugly, like a 90's sci-fi B movie prop, but with them being so handy i can overlook. 

[johninderby]

Think this is a “Marmite” type of thing about what type of finder or combination thereof that you prefer.  

Interesting to read the differing opinions though.  

[Pete Presland]

I use both on my newt, but just a magnified version on  my C9.25, Perfect for finding Venus in the daytime and the outer gas planets.

[Mr Spock]

I have two finders on my C9.25 - the standard 6x30 straight through and a 9x50 RACI. Each has its uses.

[iPeace]

Depends on the scope I'm using. Short frac - RDF only. Low power eyepiece makes frac its own finder for stage two - but I'm using the short frac to be able to enjoy the wide view anyway, so it's worth the eyepiece switch involved for detailed observation when desired.

Longer newt - RDF and RACI. A good RACI, one that takes a decent eyepiece, is great for stage two as it shows more sky than I can see through the newt and in the 'correct' orientation. Use an illuminated reticule eyepiece for even more precision.

[Roy Challen]

My binoculars don't need any sort of finder - I just point and look?. Anything else is too much like hard work. 

[25585]

I have both a Telrad and finder scope. I need both to zone in. 

An easy example is finding M13 or M31. Not visible to the naked eye, but can be seen in binoculars - which have the same OG size and magnification as your typical 8 x 50 finder. So both are needed. Star hopping is not as easy as made out to be, like rock hopping they all look alike, so it's easy to take what looks like the right direction, may not be. 

People who use DSCs &/or Goto may not need RDF, but finder scopes still have a need to aid with precise centring especially when using narrow FOV eyepieces.  

[Roy Challen]

For those who do use Telrads or similar, but find them ugly (which they are) why not use a  red dot rifle scope?  Same thing, but much more aesthetically pleasing.

[25585]

9 hours ago, Davey-T said:

It's hard enough finding stuff with a finder scope at 2500mm f/l when the little square formed by the double crosshairs in the finder is the same size as the FOV.

Dave

I have a small frac which takes interchangeable 1.25 inch eyepieces. Best solution. 

[25585]

3 minutes ago, Roy Challen said:

For those who do use Telrads or similar, but find them ugly (which they are) why not use a  red dot rifle scope?  Same thing, but much more aesthetically pleasing.

Good especially with changeable reticules & usually decent eye relief. However they are only straight-through. 

[DaveS]

My first finder was a home-made job with a 60mm objective and an Erfle of unknown fl that I put crosswires in myself. I didn't have a red dot until I got my Meg90. I had a Telrad but sold it at the last SGL.

Now I don't have any finder as I use a sky model and an encoder mount.