Decent Eyepiece recommendation for small dob?

[mickb]

Hi guys, I used to skywatch a long time ago and decided to get back into the hobby with the kids. As such I picked up one of those little Heritage 130mm collapsible table top dobs. Its not a bad little unit and should be suitable for young kids to learn off, (and dad to relearn what he is doing!)

I wondered if someone could suggest a decent eye piece? I was looking at 5-7mm, 60degree or more FOV, price point/quality up to $170, of which there are quite a few choices but also had a concern about the weight of the eye piece. I assume it might make tracking this small scope difficult? (I don't mind if its quality is overkill since I can use it for larger scopes later)

Had the chance to pick up a used baader hyperion but was worried at 350+grams or whatever it would be too heavy. Thanks for any opinions on that?

[janoskiss (Steve H)]

Maybe give the Skywatcher planetary EPs a go http://astropetes.com.au/accessories.html (so-called ultra wide angle EPs, but they're 58 deg) - they superficially appear to be TMB Planetary clones. You're right about Hyperion being too heavy.

The scope really does not warrant expensive EPs IMHO, but something better than the included cheapies is a good idea. I'd just get better FMC Plossls, a 25mm and a 15mm, and a barlow for higher powers (also to help tame some of the aberrations of the short FL mirror).

[AEAJR (Ed)]

I just picked up a Meade HD60 eyepiece in the 4.5mm configuration. 60 degree view. Very comfortable eye relief and good view. It is HUGE compared to my 26, 9.7 and 6.4mm Meade 4000 super plossls. I have used it in my 8" dob, F5.9 and my 80 mm F5 refractor.
http://www.sirius-optics.com.au/tele...eyepieces.html

[mickb]

Thanks guys . I will give the meade 5000 a try through Sirius optics.

Would I be pushing my luck to use their 4.5mm eyepiece for this scope on average nights? focal length is 650mm..

[Atmos (Colin)]

A 4.5mm would be good on a night of average-good seeing, 144x isn't over the top.

[AEAJR (Ed)]

They have a 6.5 if you prefer that.

[mickb]

Yes, I'd prefer as much magnification as I can safely get away with for this eyepiece so will have to make a decision between the two..

[AEAJR (Ed)]

Using 2X aperture guideline, a 130 mm scope should be able to handle 260X if the conditions will allow it.

Some prefer to have a series of eyepieces for each mag and some prefer to have half as many eyepieces and a 2X barlow. A 6.5 would give you 100X. Barlow it to 200X. 4.5 would give you 144X. Barlow would take you to 288X

Of course nothing prevents you from going higher. Just using the 2X aperture as the benchmark.

I have been told the Celestron X-cel is the same eyepiece under a different label. I can't confirm it but the Celestron seem to be lower cost. FWIW.

[mickb]

Originally Posted by AEAJR

Using 2X aperture guideline, a 130 mm scope should be able to handle 260X if the conditions will allow it.

Some prefer to have a series of eyepieces for each mag and some prefer to have half as many eyepieces and a 2X barlow. A 6.5 would give you 100X. Barlow it to 200X. 4.5 would give you 144X. Barlow would take you to 288X

Of course nothing prevents you from going higher. Just using the 2X aperture as the benchmark.

I have been told the Celestron X-cel is the same eyepiece under a different label. I can't confirm it but the Celestron seem to be lower cost. FWIW.

Thanks AEAJR, conditions here probably aren't great, humid tropics, moisture in the air all the time. Maybe these are okay conditions by other standards? Not sure. I'd prefer to run on eyepieces for this one anyway to keep weight down. Can I ask which eyepiece you meant as being the same as the X-cel. I googled the X-cel and appeared to be signicantly larger more expensive unit like the hyperions?( maybe just in Australia)

[AEAJR (Ed)]

I have the Meade 5000 HD60 4.5 mm.

Sorry for using USA based source, but this is just for comparison.


The 6.5 mm is the same size as the 4.5 mm. This is a 6 element eyepiece that is very large, about 10.6 ounces. 3X the size of my Meade 6.4 mm plossl.
http://www.amazon.com/Meade-Instrume...5000+eyepieces



The Celestron X-cell LX series appears to be similar. I have read that they are the same. 10.5 oz I cannot confirm it.
http://www.amazon.com/Celestron-X-Ce...stron+x-cel+lx


Compare the HD60 to a Meade 6.4mm Series 4000 super 4 element plossl at 3 ounces, about 1/3 the weight.
http://www.amazon.com/Meade-Instrume...s=Meade+6.4+mm


Combine that with a Meade 2X shorty Barlow at 2.3 oz and you are a total of 5.3 oz., about half the weight of the Meade HD60
http://www.amazon.com/Meade-Instrume...s=Meade+barlow


The HD60 will have longer eye relief and is a bit sharper at the edges with a little wider field of view (60 vs 52 degree AFOV)

I am not pushing either approach, just trying to help you make informed decisions. If weight is your concern the HD60 or the X Cel LX is the heavier more expensive approach. Some would say the better approach but that is for others to suggest. It is your money and your goals, not mine.


I don't know what eyepieces you have now but, if I was working with children, I would go for a zoom and a barlow to cover the full range of magnifications without having to fool around with switching eyepieces. I have the Celestron 8-24 zoom and it is my most used eyepiece.

In your scope, 650 mm, that would give you 27X at low power and 81X at high power. Throw in the 2X barlow and you are at 54X at low and 162 at high based on 2 pieces of glass. Put in a 3X barlow and you are at 81X to 246X. Full range of mags in 1 zoom and two barlows.

I believe the Meade and Celestron 8-24 are the same unit with different labels. I have the Celestron which is less expensive than the HD60 single FL eyepiece but about the same size.

Each to his own approach but I wanted to share my experience, FWIW. This is not going to compete with high end single FL eyepieces but I find the view quite acceptable and when I am working with kids the only eyepiece I use is the zoom or zoom plus barlow.