Which do I buy next?

[BobInYorkshire]

I’m a complete newbie, I bought a Skywatcher 100 ED Pro a couple of weeks ago that came with a 28mm EP, I knew I’d have to buy others and decided to go for the Baader Morpheus.

I’ve just purchased the 17.5mm one and would like advice on which one to buy next, 14, 12.5, 9 or 6.5.

I'm still unsure as to what I want to view, as a newbie I’m just hoping for some clear sky so I can go and have a look at anything, eventually my goal would be some astrophotography but I just want to explore for now and get used to the scope.

All advice welcome.

Bob

Edited September 2, 2021 by BobInYorkshire

[scotty38]

I have different scopes but even so i have the 17.5 and 9 is most likely next for me and and would seem to make most sense with the mag jump....

[Stephen_M]

FWIW, I have the 14mm and 17.5mm. I got the 14mm as it was the only one in stock at the time earlier this year. I then added the 17.5mm as I thought the reduced magnification might help me spot DSOs in my suburbian skies.

However, I really can't see much difference between them unfortunately. My plan is to skip the 12mm and go to the 9mm next. I can see myself selling one of these two eventually as I'm not sure their is much benefit to having both.

[GoldTop57]

Have you thought about the baader hyperion zoom mark IV?

[John]

The run of focal lengths that I use with my 900mm focal length refractors (100mm and 120mm aperture) is:

24mm - 17.3mm - 14mm - 10mm - 7mm - 5mm - 4mm-2mm zoom

To be honest I tend to skip the 17.3mm very often and move straight from the 24mm to the 14mm. 

Don't know if that helps

 

 

[F15Rules]

I like John's logic, and I think you could achieve a set to suit your scope, but with not too many eyepieces as follows: ( I should mention that I have the 17.5 and 9mm Morpheus units, and rate them both very highly)..

As the core of your set I'd suggest the 6.5mm, 12.5mm and 17.5mm Morpheus's. These are pretty much parfocal (ie each eyepiece can be interchanged with little or no need to re-focus).

The Morpheus's do Barlow very well, so if you get a Baader Hyperion zoom 2.25X Barlow, you would end up with the following magnifications in total in your scope:

6.5mm - 311x (with Barlow) and 138x eyepiece only

12.5mm - 162x and 72x

17.5mm - 51x and 115x

Or, in order of low to high magnification..

51x, 72x, 115x, 138x, 162x, 311x

In addition, I'd recommend a low power widefield eyepiece of between 24mm and 32mm focal length. If you want an all 1.25" barrel set (so you don't need to buy a 2" diagonal as well, you'd need to stick to c24 mm focal length. A very good eyepiece often available used for c£100 is the Explore Scientific 24mm with a wide 68degree field of view (there is one for sale on UKABS currently for £110, nothing to do with me!). This would give you a very nice 37.5x in your scope, and show you lovely views of clusters and nebulae such as M42 (the Great Nebula in Orion).

HTH and good luck with your new hobby!👍

Dave

[BobInYorkshire]

1 hour ago, GoldTop57 said:

Have you thought about the baader hyperion zoom mark IV?

Thanks, yes I have but wasn’t really sure if it would be the same optical quality as the individual ones.

[BobInYorkshire]

21 minutes ago, F15Rules said:

I like John's logic, and I think you could achieve a set to suit your scope, but with not too many eyepieces as follows: ( I should mention that I have the 17.5 and 9mm Morpheus units, and rate them both very highly)..

As the core of your set I'd suggest the 6.5mm, 12.5mm and 17.5mm Morpheus's. These are pretty much parfocal (ie each eyepiece can be interchanged with little or no need to re-focus).

The Morpheus's do Barlow very well, so if you get a Baader Hyperion zoom 2.25X Barlow, you would end up with the following magnifications in total in your scope:

6.5mm - 311x (with Barlow) and 138x eyepiece only

12.5mm - 162x and 72x

17.5mm - 51x and 115x

Or, in order of low to high magnification..

51x, 72x, 115x, 138x, 162x, 311x

In addition, I'd recommend a low power widefield eyepiece of between 24mm and 32mm focal length. If you want an all 1.25" barrel set (so you don't need to buy a 2" diagonal as well, you'd need to stick to c24 mm focal length. A very good eyepiece often available used for c£100 is the Explore Scientific 24mm with a wide 68degree field of view (there is one for sale on UKABS currently for £110, nothing to do with me!). This would give you a very nice 37.5x in your scope, and show you lovely views of clusters and nebulae such as M42 (the Great Nebula in Orion).

HTH and good luck with your new hobby!👍

Dave

Thanks for advice, the 12.5 followed by the 6.5 seems like a plan to me. I’ve just got to raid the piggy bank again!

[Don Pensack]

A 40% jump between magnifications, starting with the 17.5mm runs:

17.5...12.5...9...6.5...4.5  Now you know where the focal lengths came from.

 

So why a 14mm?  Because it was the longest focal length possible in the original formulation of the design.  It really wasn't in sequence with the other focal lengths.

They tried 3 different designs for the 17.5mm until they landed on a good design, but the 17.5mm is different internally than the others, and has different eye relief (longer), a different apparent field (slightly smaller),

and one note: the Baader data is incorrect--the field stop in the 17.5mm is 21.7mm, not the 23.5mm Baader quotes.  I think this was changed somewhere in between the 3 prototypes they tried.