sleeper gem barlow - Orion Deluxe 1.25"

[janoskiss]

I've been trying to get one of these for ages. Finally got one!
Orion Deluxe 1.25" 2x barlow.

This is one of the best 1.25" barlows available for high power. A real sleeper too at just $99!

This and its bigger 2" brother are the only barlows I've seen with internal baffling, and give better contrast on planets than any other barlow I've used, including Televue barlows and powermates. The 1.25" did not disappoint on Jupiter - at least good as the 2" unit.

The internal baffle does present a fairly modest clear aperture, so long focal length EPs will vignette. This is not a barlow for the 24mm Panoptic. But if you are like me and use barlows for high powers only (don't barlow any EPs with F.L. longer than 15mm), this is the barlow to get. Perhaps worth mentioning also that this is a better barlow than the much more popular Orion product, the Shorty Plus. (unless of course you specifically need a short barlow e.g. for reaching focus with a refractor + diag...)

The barrel is nice and long, and like the 2" version, this barlow yields lots of out-focus - would be good for high power binoviewing. The long barrel will also ensure that chromatic and spherical aberrations are not an issue.

The lens coatings are the best I've seen on any barlow. Under overhead halogen lighting they compare favourably with my Televue barlow, with the Orion Deluxe showing darker reflections. (see last two photos - note: same lighting, same camera aperture, exposure and ISO settings.)

[iceman]

Where did you get it from? 2nd hand or new?

[janoskiss]

Sorry, forgot to say. Sirius Optics in QLD. $99 + postage new. For the quality of the product it's an absolute bargain. All metal body btw, but still quite light. I don't know of any other place that sells them. Bintel sell the 2" version - I approached them first about the 1.25" but was told they cannot get it so went with the QLDers.


I know a lot of people are going to be skeptical of that statement, so I thought I'd elaborate...

IME you always get some "anomalous" light, scattering and/or reflections (from eyeball or o/wise) in a non-baffled barlow - especially when barlowing complex large FOV EPs - e.g. XW or Nagler T6 in TV barlow or powermate. Not to a great extent (and many people would not think it worth mentioning) but certainly enough to tell one is using a barlow. With a good barlow like eg TV, these can often be eliminated or minimised by readjusting one's head & eye position for best view. But with a dob this has to be done continually as the object (usually planet) moves across the FOV and it gets tiresome and one wishes one could do away with the barlow. The baffled Deluxe barlows are the only exception IME, delivering the highest contrast views of the planets across a dark sky background without any fuss.

[Starkler]

Very interesting report and I admit I was a bit taken aback when you said that it's superior to the tv barlow.

Now that luna is out it might be possible to give it the acid test re internal reflections and scatter.

[freespace]

Hrm, this is really interesting. Currently I have a bintel 2x barlow which in length is the same as the Orion Shorty. I think this barlow would be a good upgrade, though I only really use it with my 6.4mm meade - would it be worth it if just for that?

Also would it cause problems seeing as I have a 4" F/5 scope in terms of being able to bring the 6.4mm into focus?

[janoskiss]

I have that barlow also, for use at parties, around kids, intoxicated folk etc. It is a good barlow for very little money. Nice FMC optics. Its main shortcoming is the black but shiney lens assembly housing. You get strong glare when a bright object is just outside the FOV, and the contrast in general is not as good as in the Orion Deluxe or Televue barlows. The other minor complaint would be some false colour off axis with wide AFOV EPs (esp when trying to push the power higher using a barrel extension).

One nice thing about the Bintel (ie GSO 1.25" 2x shorty) barlow is that the lens assembly can be unscrewed and screwed directly onto the filter threads on any 1.25" eyepiece to give 1.6-1.8x magnification. Could be a good fairly cheap permanent fixer upper for use with lesser widefield EPs in fast scopes. (some treatment of the shiney metal surface with a matte black coating would be a good idea..)


Barlowing the 6.4mm will yield too much power for that scope IMO.You would not have any problems with focus though.

[freespace]

Thanks for the tip about the unscrewing part - will try that out :D :-)

I thought the rule of thumb for practical power was 20xper inch of aperature, so for my that should be 200. 500mm focal length with barlow and 6.4mm is only 156X magnification, which should be fine? In my experience it has been.

Cheers,
Steve

[janoskiss]

154x should be fine if it's a high quality scope like an apo. If it's a 4" f/5 achromat, or Newt even, then I would not think it worth pushing beyond 100-120x.

[freespace]

Ah ok. Its only a achro, can't afford a apo :P

Cool, thank you very much for your help :-)

Cheers,
Steve