Hard to look at Dob finderscope by left eye

[SingleWord]

I always use my left eye to look through the finderscope but that's tired by leaning towards the Dob, it causes my neck pain.
Any adaptor or piece of part can make it right-angle like finderscope so that I can just view as the focuser position?
I mean by adding the new part to my existing finderscope, not to replace with new one.

[torana68]

Get yourself a new or second hand 90 degree finder. Get one bigger/better quality than your current one as an upgrade whilst your at it. Modifying yours can be done but its not worth the effort.

[astro744]

Not easily done as you add length to the optical path and to surmount this you usually have to shorten the tube unless the finder was already designed this way in which case you need an extension for straight through operation.

Note a right angle finder will reverse the image left to right no longer matching the sky or star chart. A Corrected Image Right Angle finder (RACI) will correct the image and match the sky and star chart. Depending on your head and telescope orientation may mean a rotation of any chart but at least it will not be reversed when using an RACI finder.

[ThunderStorm]

At the moment the scope finder is already reverse the image.
Saturn viewing again, when I look through the scope finder (on and before 8pm), Saturn was on the top left hand of moon via the scope finder but actual should be at bottom right hand of moon.

Am I understand correctly?
Not sure if OP has the same thing as mine.

[astro744]

A reversed image is back to front. e.g top left reversed would be top right. A shift from top left to bottom right is likely upside down. If you rotate the image (or your head) the view will be right way around.

Note the orientation of the head with respect to the telescope, horizon and object position all cause rotation of the image.

A straight through finder will show an upside down image but not a reversed one. For reversal you need an odd number of reflective surfaces.

A reversed image cannot be matched up with a star chart whereas an upside down image can.

[ThunderStorm]

As OP said about Saturn/Full moon last week, when I looked through both scope finder and eyepiece, the Saturn moved from top left corner of moon to bottom right corner.

The actual appearance(visually) is from bottom right corner to top left corner of moon, so it was up-side-down and left-side-right, is that correct?

[mental4astro]

A few things to consider about finder, optical and red dot finders.

1, You don't need to use just one eye. If the finder is a straight through type, use BOTH eyes. The 'free' eye and the 'finder' eye images will meet at a single point when the finder is on target. I do this with both my optical and red dot finders. I too used to use just one eye, but a chance moment of distraction had me looking through my optical finder with my 'free' eye open - scope movements relative to the finder stayed the same, and the aiming operation worked even faster! You can close your free eye at will if you need to tweak things.

2, If the position of the finder is poor due to it being close to the body of the scope, LENGTHEN ITS STALK. It will raise the finder up off the scope, and actually place it at a more comfortable position so you don't need to stoop so much. I did this to my 8" solid tube dob's red dot finder. The ONLY reason this is isn't offered by manufactures is it means that they need to double up on their accessories range, even though it makes things easier for the end user. Manufacturers don't have all the answers, and is upto us to make the changes they don't.

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3, Change the position of the finder. No reason why you can't remove the mounting block of finder and put it on a different part of your scope! There is a bloody lot of empty space on the outside of the OTA, and the finder mounting block is placed where it is for the convenience of the manufacturer, not the customer. Every customer is different, have different habits, different eye capabilities, different degrees of movement - different. This makes particular sense if your preferred 'finder eye' is your left one, and the finder is set such that it would be easier for your right eye to use it, such as the situation with my 8" dob pictured above.

4, Fit multiple finders to the scope. Not as crazy as it sounds. Optical finders and red dot finders have a different set of pro and cons. Coupling both to the scope not only can make things easier, but offers counterweight advantages too. I have three finders on my 17.5", two optical and on rdf. I designed this feature deliberately into my 17.5" as I knew that when I used excessively heavy eyepieces, all I needed to do was remove the highest set optical finder and balance as re-established, and I still had finders to use. The other two finders being lower set, also allow me to point the dob while my feet a on the ground, not up the ladder. Then, in practice, I mainly use the rdf first, and then the higher set optical finder. The second optical finder comes into use mainly when the high-set one is off the scope. It is also a larger finder that I then use when chasing really difficult targets - Advantages all round for me.

This next pic shows all three finders on the OTA of my 17.5" while the OTA was being tested while it was being built.

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5, Straight through and right angle finders have different applications, and also don't suit everyone. BUT, there is a great trick and a brilliant little gizmo that may help a lot of people with dobs and Newtonians, a double finder mounting block! (http://www.bintel.com.au/Accessories/Finderscopes/Orion-Dual-Finder-Scope-Mounting-Bracket/1768/productview.aspx) You can mount a red dot finder on one and a right angle finder on the other. You can do your gross pointing with the rdf, and fine with the right angle finder as you then don't need to do mental gymnastics with your charts (paper or digital). You also end up with the counterweight advantage mentioned above too.

Just some other ways finders can be used.

Mental.

[astro744]

Try to focus on a street sign and you will see if the text is upside down or reversed or both.

Note upside down may be sideways depending on how you are positioned and how you turn your head. You'll get the idea a bit easier if you focus on something on the ground/horizon rather than in the sky. You can then try on the Moon and note which features are where and you'll see what the telescope and finder are doing.

Try to turn your head and see what the image does too. It is a good idea not to think of upside down, left or right but rather north, south, east & west. Point to something due north and then nudge the telescope north and see which way the object moves. Then nudge east and also see what happens. You'll soon get your bearings.

[SingleWord]

Do you think this Saxon can do the job?
http://www.aliexpress.com/item/Explore-Scientific-8X50EF-Just-right-angle-illuminated-finderscope/1682851063.html

[astro744]

Both illuminated and non-illuminated RACI finders can be found at much better prices and local here: http://www.bintel.com.au/Accessories/Finderscopes/49/catmenu.aspx

Just check that the foot matches your telescope finder base.