Observing the Pleiades

[william123]

How wide of a true field of view (TFOV) does one need to observe the entire Pleiades cluster well?  Will 2.3 degrees suffice?  Will 2.7 degrees suffice?  I know this may be an odd question, and I know that good binoculars may be the best answer ultimately, but right now I'm trying to determine, without access to any equipment, the minimum TFOV for a pleasing observation through a telescope.

Thank you.

Bill

[ronin]

2.3 should manage them, although 2.7 would likely be better..

Sizing these gets difficult as there is nebulosity associated with them the question is  "Where does it end?"

If you get a better scope, collect more light and if imaging a better more sensative camera and you can add to the size. Another example is M42, it seems to get a little bigger every so often for this reason.

I used to consider M54 as about a degree across, raised that to 1.5 degrees. Not sure if they have yet made 2 degrees, so as said initially 2.3 should do them well, and 2.7 would sort of frame them. Some depends on your preference for seeing them as in biger and just fitting in the view or smaller with darkness surrounding them.

[Moonshane]

2 degrees is plenty

[Stu]

As Shane says, 2 degrees is plenty to fit M45 in, although I prefer to see it with some surrounding dark sky as it puts it in context better.

This shows it with Telrad circles (0.5, 2 and 4 degrees) so might help a little. I think 2.5 to 3 degrees would give it plenty but this is often about personal preference.

Stu

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[Pig]

My 80mm refractor easily fits M45 in the FOV using a 25mm 50 degree eyepiece, I call it a scope that gives binocular views  

[Stu]

The outer blue ring is my Genesis with 31 t5 Nagler in it. Gets a bit silly :-)

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[william123]

Thank you, everyone!  You told me just what I wanted to know!

I have a 130mm f7.7 apo coming soon, and I wanted to know whether my 35 Panoptic would show the Pleiades properly with the scope.  The 35 Pan will give me 2.2 degrees TFOV, so it should be alright.

Bill

[Stu]

Looks ideal to me :-)

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[Moonshane]

here's a recent sketch done with my 12" dob which with the 40mm TV widefield eyepiece has a field of 1.9 degrees even with the paracorr (2.1 degrees without)

[ollypenrice]

Yes, I have a similar FL (980mm) in our TEC140 and with a 26 Nagler it's a great view. A little wider would be even better. Should be stunning. Get after that nebulosity! A high position in the sky is the secret.

Olly

[pyrasanth]

The details for the M45 image below is:

******** ASTROMETRIC SOLUTION RESULTS ********

Center RA: 03h 46m 16.91s

Center Dec: +24° 13' 37.3"

Scale: 3.38 arcseconds/pixel

Size (pixels): 1374 x 1099

Angular Size: 1° 17' 23" x 1° 01' 54"

Position Angle: 84° 39' from North

RMS: 1.70 (X: 1.33 Y: 1.05)

Number of Stars Used in Solution: 61 (97%)

FWHM: 2.53 pixels, 8.53 arcseconds

*********************************************

You can see at this resolution it captures most of the cluster.

[Beehive67]

As Shane says, 2 degrees is plenty to fit M45 in, although I prefer to see it with some surrounding dark sky as it puts it in context better.

This shows it with Telrad circles (0.5, 2 and 4 degrees) so might help a little. I think 2.5 to 3 degrees would give it plenty but this is often about personal preference.

Stu

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Wow...this is a  cool presenation .Are there more than 7 stars and wish one can't be seen by eye ??

[Stu]

There certainly are more than seven stars. I've seen 8 with the naked eye I think, and there are reports of people with excellent eyesight being able to see 14 or more under excellent conditions.

I'm not sure but this there maybe several hundred in all in the cluster

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