Meridian Flip Question EQ6-R Mount

[PKay (Peter)]

Hi Clever Ones

Tonight I plan for the first time to image across the meridian (NGC253).

I have never done the flip thing before.

Synscan gives me three options: Auto flipping, Force flipping & No flipping.

Questions are:

Should I go Manual (force) or Auto?

On Auto when will the flip occur: before or after crossing the meridian?

On Manual should I force it before or after crossing the meridian?

Is there anything I should be aware of: like cables, camera hitting tripod, re framing the image etc?

[_Jimmy (Loren James)]

Originally Posted by PKay

Hi Clever Ones

...

Synscan gives me three options: Auto flipping, Force flipping & No flipping.

Auto means the mount will determine if a meridian flip is required as part of the slew when the goto command is issued. I haven't used the newer paddles so I'm not sure if this will perform a flip on an object while tracking.

Force does what it sounds like - it forces a meridian flip regardless of one being required at the time the goto command is issued. SO if your scope and equipment is small enough and the object is relatively high in the east, you may get away with forcing the flip at the start and letting it run through the meridian and into the west.

No Flip - even if a meridian flips is required (e.g. going from an object in the east to one in the west) the mount will not perform a flip. Just be careful and watch your equipment.

Should I go Manual (force) or Auto?

If you are shooting from the start of the night and it's well in the east, leave it on auto, unless your equipment has enough room and won't hit the mount by starting off flipped.

On Auto when will the flip occur: before or after crossing the meridian?

As above, at the time the goto command is issued it will determine if it needs one then.

On Manual should I force it before or after crossing the meridian?

Either or, just do it when you finish a shot and are basically there.

Is there anything I should be aware of: like cables, camera hitting tripod, re framing the image etc?

All that, especially if you are starting off in a flipped state. Watch your cables especially. I now do a rotate test with my cables as part of setting up to make sure I've allowed enough slack.

You will most likely need to reframe the image after. It will be inverted, this isn't a problem, but the alignment is usually out after a flip so it most likely wont be framed the same.

I use SGP for imaging. It has an auto flip and re-centre function where it will perform the meridian flip then platesolve on the other side the match up the middle of the frame to the last one and kick off your imaging again so you can just keep enjoying a beer.

CHheers,
Jimmy.

[PKay (Peter)]

Thnx Jimmy

I am getting a feel for what is required. Today I might pick a star near the meridian and play with things (with the lens cap on).

[PKay (Peter)]

Just worked it out.

Only a few minutes ago (9.00AM) I performed a dummy 1 star alignment on Sirius. Of course I couldn't see it, but the mount doesn't know that.

I then used GOTO and aimed at NGC 3121 which was at 85 degrees alt.
(East of the meridian).

Synscan was set to Auto Flip.

I used GOTO again for the same object - nothing happened.

Watched and waited and the scope passed through the meridian. Nothing happened. If I did NOT interfere, the camera was going to crash onto the tripod leg.

So, I used GOTO again for the same object.
This time, the mount did the flip.

So, In summary, if I want to image across the meridian, I have to be there to take manual control. Otherwise disaster.

Attached 2 photos: One just before the flip and one after.

[fsr]

IIRC, Synscan only performs flips as part of a GOTO operation. Also, changing the flipping mode is only for the next goto, then goes back to automatic.
I remember reading about setting slewing limits on the mount, to avoid things hitting the legs, maybe you want to take a look at that part of the manual.