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View Full Version here: : Finder scopes, what do you use?


xnomad
17-03-2009, 05:03 PM
Hi,

A bit of a beginner question here as to what finder scopes people use. I'm using the straight through 6x30 that came with my Skywatcher 127mm Mak Cas.

All I can say is thank God I've got a pair of 10x50 Binos.
It really helps me locating objects and then putting the finder on it; however I'm really struggling with the upside down image in the finder when it comes to star hopping.

I'm tempted to part with more cash for a 'correct image' finder. I'd prefer to see the same image as the binos so that I can star hop more easily.

Is this just a learning curve issue or do others simply go with a 'correct image' option?

The 2 things that put me off getting a new finder are the following: Firstly I've spent a lot of money lately on the scope, and then on eyepieces, barlows and books etc, and I'm feeling guilty with what seems a new purchase every week! (My fiancee' would kill me if she knew!)

Secondly I like to use both eyes with the finder so that I know the star in the finder is the star I'm looking at with my naked eye. This won't be possible with a diagnoal on the finder.

Is it possible to remove the diagonal and use it as a straight through when required?

What do you do?

Quark
17-03-2009, 05:52 PM
I have a straight through 8 x 50 finder and a Telrad. I use the Telrad to get me in the right area and then use the finder. I use both eyes with the finder to centre what ever the target object is. Some of my friends have right angle finders but I would much prefer the straight through variety, as then you can use both eyes to centre the object.

Trevor

I do have a portable scope that I take out in the field and it has an 8 x 50 straight through finder and a red dot finder that I use in a similar vane to the main scope in my observatory

PCH
17-03-2009, 05:53 PM
G'day Xnomad,

I and many others on here have a couple of things to help us align real quick.

I use a red dot finder scope. These are around $75 and you just look through it from behind until you can see the approximate area that you want to look at thru your scope. Next I hop to my right angle (read erect image) finderscope where I can quickly position the object of desire in the centre of the cross hairs. And then just look through the scope, and assuming these two devices have been set up (aligned) correctly, your object will be near the centre of your field of view - fov for short.

This all takes just a couple of seconds when you've done it a couple of times and it really does make viewing easy.

Cheers,

GeoffW1
17-03-2009, 08:47 PM
Hi,

After weeks of getting a sore neck I bought a Bintel right-angle correct image finder. With that I use a Telrad finder, it is an ideal combination for me.

Enough skiting, what I mean is that I start by eye with a star chart to make sure I have the Constellations identified and the right way up (no flannel, many star charts are printed for the Northern Hemisphere, which is upside down) and align the Dob roughly with the Telrad. Then the field of view in this RA finder is wide enough (it is 8 x 50 like a monocular) to keep myself oriented enough to get the desired star in the crosshairs. After that a small nudge gets it in the eyepiece too. Star hopping is only a matter of repeating this. I find it helps also if you can get really distinctive stars in the finderscope like Betelgeuse or Acrux.

What is a pain is those times when I have had the Telrad or the finderscope unmounted (I do that sometimes for perverse reasons) and I have to line everything up again. There have been occasions when I had one star centred in the finderscope and another in the eyepiece! And then I drop the little screws in the long grass :mad2:

If you ever get the very popular Argo Navis it will make you lazy, after aligning all you do is dial in the desired destination and push-to it.

Cheers

jjjnettie
17-03-2009, 09:26 PM
My 10" dob came with an 8x50 right angle finder and I wouldn't use anything else now.
You can't remove the diagonal.
Adding a red dot finder is an excellent idea.

As for feeling guilty about the amount of money you've been spending.
Well, you might as well get used to it because this hobby is a money pit.:lol:

erick
17-03-2009, 10:05 PM
I'm with you. Straight through finderscope with both eyes open.

But I have a beauty. An erect image straight through with illuminated crosshairs - bought from Japan. See my post in this thread:-

http://www.iceinspace.com.au/forum/showthread.php?t=40879

When I can, I use a laser pointer on the scope which usually gets me directly into my widefield eyepiece, bypassing the finderscope.

ps. I'm now a "lazy" user of an Argo Navis so I don't have to look through the finderscope as much as I used to.

AlexN
17-03-2009, 10:08 PM
I too am a red dot finder kind of guy... I love my red dot finders... I do have a 9x50 finder on my C11, unfortunately its a straight through, I prefer right angle finders... However I rarely use my finderscope... as my red dot finder is pretty spot on.. when I line something up in the red dot finder, its usually within the approximately 12x12 arc minute field of view given by my camera/scope.. I then center it in the cameras field of view, and away I go..

GrahamL
17-03-2009, 10:27 PM
I like my f50 a lot and have become quite partial to swapping
eyepieces in it http://www.cloudynights.com/item.php?item_id=1324

Don't know much about these but they are the right way up
http://www.cloudynights.com/item.php?item_id=1324


Well ..cant have that !! so best you don't tell her and hide it someplace:thumbsup:

[1ponders]
17-03-2009, 10:44 PM
I like the straight through with both eyes open. Too easy. ;) :thumbsup: Though I must admit my erecting RA illuminated Stellarvue is a dream to use. Would be better if it was straight through like my other illuminated finder. ;)

leon
18-03-2009, 02:57 PM
Yep, straight through is my choice as well, ;) although one can get one's neck in some mighty difficult positions, I use a Takahashi Finder, man is that thing clear. :eyepop:

However one could buy several other Finders for the price of that one. :whistle:

Leon :thumbsup:

dannat
18-03-2009, 03:06 PM
Same leon - I use the intes one, 8x50 very clear, ep focus - way above the synta 6x30 - they are more difficult to use

gmbfilter
18-03-2009, 05:20 PM
35mm Tele Vue panoptic don't bother with a finder.
At the time it seemed like a good idea.
Originally used it in an ED80 + HEQ5PRO mount, even with dodgy alignment most times stars are in the field of view

I eventually got a red dot finder for about $60 so I could see what part of sky the scope was pointing to

Greenswale
18-03-2009, 06:38 PM
I'm using a Telrad, previously a had red dot on a Celestron.

The red dot is quick and easy, two eye use, pretty good, perfect for getting stuff into the eyepiece at 60x (25mm Celestron Plossl) when properly aligned. (I prefer the word 'harmonised' rather than 'aligned'...has to do with fighter aircraft gunnery systems, but means right on target....)

I've gone to the Telrad on my new scope because I want to learn the sky. Using a good sky map, occasional use of binos to get into an area (particularly in light polluted suburbia), then using the Telrad calibrated circles to move about, I can get onto targets pretty easily. I can aim accurately enough to get an object in the lens (Pentax XW7) at 170x if I'm a bit lazy with lens changes.

Its not the best two eye finder. I fitted a dew shield (has a mirror installed to allow 90° viewing, and found that this made two eye use more difficult, but dewing has been stopped.

I am quite happy with the Telrad and can't see the need for anything else with my current set up.

Wren

xnomad
18-03-2009, 07:48 PM
Thanks for all the info guys, looks like I'm going to have to part with some cash as the current setup is difficult. Last night I was pointing up near the zenith and even had the tripod fully extended and still was hating the finder. Maybe I'll find a way to strap the straight through next to a finder with a diagonal.

Robert9
19-03-2009, 09:03 AM
Very interesting reading through this post. I have been looking to change from my red-dot finder as I find the contortions my back has to endure are creating problems for me. I would like a right-angle finder, but how well do these work if you don't have an illuminated graticule? Perhaps a Telrad mounted to the side and at the front of the scope might be better option. Or perhaps even a combo, as you use Geoff?
My scope does have GOTO but even the initial alignment I find painful, especially on high alignment stars. Also the GOTO isn't helping me learn the skies. Any other thoughts?

Robert

Greenswale
19-03-2009, 09:21 AM
Robert,

The Telrad dew shield plus, available from Bintel, incorporates a mirror that facilitates viewing at various angles around 90° from the sight line.

Go here to read a bit about the sight: http://www.company7.com/telrad/products/telrad.html

And here to understand the dew shield: http://www.astromart.com/articles/article.asp?article_id=178

Wren

Robert9
19-03-2009, 09:49 AM
Wren,
Thanks for those links. I couldn't see how it could be adjusted for right angle view though. Is that a "fiddle"? The review comments a little on quality too, though there are obviously many happy users. You don't happen to live any where near Waverley?
Robert

Insomniac
19-03-2009, 03:14 PM
I've got both a Telrad (optional dewshield fairly useless!) & a 7 by 50 right angle finder despite having a go to. Must say, I wouldn't give the latter up because I still enjoy the occasional wide view through the finder & often end up slewing to something that catches my eye there. Just wish the cross hairs wern't so obvious & intrusive. Don't worry; they never disappear, despite being unilluminated. I'd much prefer a finder with a tiny thin cross at the centre of the fov. Do they exist?

Robert9
19-03-2009, 04:10 PM
What's the problem with the cross-hairs? Do they interfere with the view? They must be very thick.
Robert

Greenswale
19-03-2009, 08:06 PM
Robert,

The 90° view is obtained by rotating the dew shield about 180° from the shielded position. The mirror is then flipped up from its rest position by use of the little extension on the side. Then, the hood/mirror is rotated to obtain a suitable view of the sighting circles in the mirror.

Cumbersome to describe! I live to the west of Melbourne, Perhaps you should drop into Bintel to have a look, as thay are significantly closer to you?!

Wren

Robert9
19-03-2009, 08:40 PM
That was a pretty good description Wren, I could actually visualise the procedure as I read your description. You ought to go into journalism!
Yes, I think a trip to Bintel (quite close) is in order. They may also suggest an angle finder with a few mags. and crossed rabbits.
Robert

GrahamL
21-03-2009, 04:54 PM
http://www.stellarvue.com/f50.html

The supplied eyepiece with this finder can be dissasembled and the crosshair insert removed or any eyepiece of your choice can be used
no crosshairs either way..havn't visited vics site for a while theres now a couple of great looking additions you can fit to this little finder by the looks:thumbsup:

Robert9
21-03-2009, 10:05 PM
Looks like a very nice finder. But its just too expensive. By the time its equipped with mounting rings or the like, the cost will be here in Oz. about $250-$300, well beyond what I would like to pay. :juggle: There are other gizmos that I "need" before such a deluxe finder.
Robert

g__day
22-03-2009, 12:04 PM
I bought a right angle 8 * 50mm GSO finder from Lee Andrews and am totally satisfied with its performance. At time I'd like greater light gathering and less magnification, but in my light polluted neck of the woods - it hardly matters. Some subjects are so faint I can't resolve them glacing through a 127mm MAK - so a finder has no chance. This is where accurate shines through. I find when my goto is working well I barely even bother to look through the finder all night.

Robert9
24-03-2009, 04:24 PM
I have to agree with you on that Matthew. A GOTO certainly in many ways negates the need for a finder beyond the initial set-up of the scope. However, for star-hopping, I think something reasonable would come into its own.:astron:
Robert

xnomad
25-03-2009, 12:41 PM
I eventually got myself one of these, just the other day. It's been a bit cloudy and windy lately but I was able to use it for a short time last night and it's just what the Chiropractor ordered ;). Also much easier to find my way around, I'm very happy with it so far.