An almost-a-report

[turboscrew]

It looks like I saw something else. I think the pair should have been harder to split, and the dimmer star should have been seen to NW from the brighter one (refractor with diagonal). I wonder what I might have seen?

[OzEclipse]

Juha,
It's very hard to tell what you might have seen from your description.

Some possibilities:

• other stars

• ghost images of the bright star - internal reflections in the eyepiece

• atmospheric dispersion can split a star into two images.

You can easily eliminate ghosts by slewing and moving the view of the bright star towards and away from the centre. A ghost image will mirror the movements on the opposite side of the field centre.

cheers
Joe

[turboscrew]

Juha,
It's very hard to tell what you might have seen from your description.

Some possibilities:

• other stars

• ghost images of the bright star - internal reflections in the eyepiece

• atmospheric dispersion can split a star into two images.

You can easily eliminate ghosts by slewing and moving the view of the bright star towards and away from the centre. A ghost image will mirror the movements on the opposite side of the field centre.

cheers
Joe

I wonder if there are other stars of that brightness that close.
I would think atmospheric dispersion would have made another star appear below the star, not SW from the star.
The reflection needs to be checked, but I guess BCOs are not notoriously famous for that.
This, obviously, calls for another attempt.

[OzEclipse]

I wonder if there are other stars of that brightness that close.
I would think atmospheric dispersion would have made another star appear below the star, not SW from the star.
The reflection needs to be checked.

As I said, from your description, I couldn't really conclude what it might be. These are just a range of suggestions of possible causes based on my own observations of similar phenomena.

[turboscrew]

It looked like this (at best), in the eyepiece (just basic diagonal - left and right swapped).
This picture (b&w) is from Wikipedia, just scaled and rotated 180° to look like what I saw in the eyepiece.

220px-Gamma_Leonis_Algieba_orientation.jpg (551 Bytes) Viewed 917 times

The colour(s) were a yellow/orange-mess (varied and were hard to detect), and the stars separated and merged (the atmosphere, I guess).

[OzEclipse]

Juha

Are you sure the orientation was wrong? How did you determine it? In a Newtonian, the field rotates depending upon the rotated position of the tube/focusser.

I usually establish orientation by using one finger to put a little pressure and push the tube south, so the star deflects north. Then I push the tube west, so that the star deflects east.

Joe

[turboscrew]

Juha

Are you sure the orientation was wrong? How did you determine it? In a Newtonian, the field rotates depending upon the rotated position of the tube/focusser.

I usually establish orientation by using one finger to put a little pressure and push the tube south, so the star deflects north. Then I push the tube west, so that the star deflects east.

Joe

It wasn't the newtonian, but the Omegon refractor on alt-az. To my understanding, it mirrors the view in respect to the centerpoint (equals 180° rotation), but the diagonal reverses the north-south mirroring.
I think, in "real life" the dimmer star should be to the NE from the brighter star, so in the eye piece the dimmer star should be in NW from the brighter star.

[OzEclipse]

When you look through a refractor with a diagonal, on an alt az mount looking at the horizon with the eyepiece vertical AND you standing behind the scope looking in, ie the direction of the objective extending from the focusser is 12 o'clock: -
=> The image is erect right way up.
=> The image is mirror reversed left to right

It has less to do with north south east west and more to do with ALT AZ. If the eyepiece is oriented vertical with respect to the horizon, it's still erect in the up down and mirror reversed left right. north/south east/west is relative to where you are pointing in the sky and where you are on Earth. If you are at the north pole, and you are closer than any of us, , then what you say is correct.

I have attached a diagram, I hope I have done the mental gymnastics correctly. You are 95 deg away from my latitude.

This is the view but only if you rotate the diagonal to tilt the eyepiece to about the 2 o'clock position, not vertical.
Hope this helps more than it confuses.

Joe

[turboscrew]

When you look through a refractor with a diagonal, on an alt az mount looking at the horizon with the eyepiece vertical AND you standing behind the scope looking in, ie the direction of the objective extending from the focusser is 12 o'clock: -
=> The image is erect right way up.
=> The image is mirror reversed left to right

It has less to do with north south east west and more to do with ALT AZ. If the eyepiece is oriented vertical with respect to the horizon, it's still erect in the up down and mirror reversed left right. north/south east/west is relative to where you are pointing in the sky and where you are on Earth. If you are at the north pole, and you are closer than any of us, , then what you say is correct.

I have attached a diagram, I hope I have done the mental gymnastics correctly. You are 95 deg away from my latitude.


This is the view but only if you rotate the diagonal to tilt the eyepiece to about the 2 o'clock position, not vertical.
Hope this helps more than it confuses.

Joe

Yes, with the directions (like NW), I meant in the eyepiece, where south is down towards you, west is on the left and so on. And yes, my diagonal (eyepiece end) points to zenith when the tube is level.

It starts to look more and more like I saw something else.

[turboscrew]

More about the little scope and gear:
This time (during cool-offs between löylys) I tried to see M51, M101 and some targets in Leo.
It didn't work out at all. The "balancing" was waste of time - in the cold, I expected the alt to become tighter, but it actually became looser. The red dot finder is pretty useless if you try to find something during the Finnish spring. You can barely see Arcturus, that's quite bright to naked eye. Dimmer stars just disappear. Also, it needs quite some yoga-lessons to be able to look, if the target is near the zenith. Then again, the AZ-3 mount doesn't bend high enough to see the tail of the big bear (Alkaid), whose altitude was 72°.
I still think that the tube itself is quite good. And even the eyepieces (super-what?) are usable. It's just that the mount and the red dot finder suck big time. While I tried to wrestle with the mount altitude limitations, Leo dived head-first behind my neighour's trees.

[Bigzmey]

More about the little scope and gear:
This time (during cool-offs between löylys) I tried to see M51, M101 and some targets in Leo.
It didn't work out at all. The "balancing" was waste of time - in the cold, I expected the alt to become tighter, but it actually became looser. The red dot finder is pretty useless if you try to find something during the Finnish spring. You can barely see Arcturus, that's quite bright to naked eye. Dimmer stars just disappear. Also, it needs quite some yoga-lessons to be able to look, if the target is near the zenith. Then again, the AZ-3 mount doesn't bend high enough to see the tail of the big bear (Alkaid), whose altitude was 72°.
I still think that the tube itself is quite good. And even the eyepieces (super-what?) are usable. It's just that the mount and the red dot finder suck big time. While I tried to wrestle with the mount altitude limitations, Leo dived head-first behind my neighour's trees.

I think it comes down to personal preferences. People like different things, naturally. I have tried fancier reflex sights and still prefer the model you have. You can see it on all my scopes.

I have used AZ-3 for a year. Did half of the Messier list with it. Basic mount but usable. May payload was even heavier than yours since I used it with 120ST. It could be that you are EQ mount guy.

Another thing to consider for the summer when you don't have enough visible stars to navigate is a small GoTo mount.

[turboscrew]

More about the little scope and gear:
This time (during cool-offs between löylys) I tried to see M51, M101 and some targets in Leo.
It didn't work out at all. The "balancing" was waste of time - in the cold, I expected the alt to become tighter, but it actually became looser. The red dot finder is pretty useless if you try to find something during the Finnish spring. You can barely see Arcturus, that's quite bright to naked eye. Dimmer stars just disappear. Also, it needs quite some yoga-lessons to be able to look, if the target is near the zenith. Then again, the AZ-3 mount doesn't bend high enough to see the tail of the big bear (Alkaid), whose altitude was 72°.
I still think that the tube itself is quite good. And even the eyepieces (super-what?) are usable. It's just that the mount and the red dot finder suck big time. While I tried to wrestle with the mount altitude limitations, Leo dived head-first behind my neighour's trees.

I think it comes down to personal preferences. People like different things, naturally. I have tried fancier reflex sights and still prefer the model you have. You can see it on all my scopes.

I have used AZ-3 for a year. Did half of the Messier list with it. Basic mount but usable. May payload was even heavier than yours since I used it with 120ST. It could be that you are EQ mount guy.

Another thing to consider for the summer when you don't have enough visible stars to navigate is a small GoTo mount.

The stars were visible to a naked eye, but looking through the red dot finder was like looking through an UHC filter.
The main problem with the mount is the altitude. At some point, a screw in the saddle hits the RA-turntable, but more often either the diagonal hits a tripod leg, or the fine-tuning cables get in between.

On a second thought, the main problem may be the attachment of the tube to the tripod. A Vixen saddle might be a good solution...

[Bigzmey]

When I needed to look up I would position the scope tube between the legs. The setup is so lightweight that you can lift the whole thing and turn around as needed to accommodate this. I would also on occasion remove the slow mo cable if it clashes with something.

For the red dot the trick it to aim with two eyes, so the red dot you see with one eye is superimposed on the star you see with the second eye.

No matter how basic or advanced your setup is, there are always some limitations, design flaws, quirks etc. to work around.

[OzEclipse]

When I needed to look up I would position the scope tube between the legs. The setup is so lightweight that you can lift the whole thing and turn around as needed to accommodate this. I would also on occasion remove the slow mo cable if it clashes with something.

For the red dot the trick it to aim with two eyes, so the red dot you see with one eye is superimposed on the star you see with the second eye.

No matter how basic or advanced your setup is, there are always some limitations, design flaws, quirks etc. to work around.

You position your scope between your legs?? How do you observe? Like this?

Position_5.jpeg (28.76 KiB) Viewed 854 times

You refractor dudes crack me up

[turboscrew]

When I needed to look up I would position the scope tube between the legs. The setup is so lightweight that you can lift the whole thing and turn around as needed to accommodate this. I would also on occasion remove the slow mo cable if it clashes with something.

Yes, looks like that. Didn't come to think about removing the cables, though.

For the red dot the trick it to aim with two eyes, so the red dot you see with one eye is superimposed on the star you see with the second eye.

Thanks, need to try that next time.

No matter how basic or advanced your setup is, there are always some limitations, design flaws, quirks etc. to work around.

Yes, I guess so.