Barlow for planetary imaging

[GlassWalker]

Having had another go at imaging Jupiter, I used both a Celestron Ex-Cel 2x and an unbranded 3x barlow. Comparing the results of the two, the 2x drizzled 1.5x looks better than the 3x. I guess I'm stating the obvious that all barlows are not equal, but the question then is, how do you choose one?

Given I have a Meade 8" SCT as my primary planetary scope (2000mm focal length, f/10), I'm thinking about getting a nicer barlow at or above 3x specifically for use in planetary imaging. Any specific suggestions?

[John]

Tele Vue Powermates are just about as good as you can get.

[VigdisVZ]

Yeah my buddy Chris does magic on Jupiter with a large newton and a 3x powermate.

[GlassWalker]

At that price, they better come with a dose of cloud repellent! While I'm not ruling it out, any suggestions say under £100?

Edit: and the TV's don't appear to come in 3x or 3.5x? They seem to go from 2.5x to 4x... concerned 4x might be a bit much.

[Damo636]

Same design as a Powermate but a lot less expensive.....

http://www.telescopehouse.com/acatalog/Bresser-SA-Barlow-3x--1.25-inch-.html

[GlassWalker]

Great suggestion. In a quick search around they seem ok and the price is a lot easier to swallow! Will look more closely in the morning...

[alan potts]

To the best of my knowledge for planets we need about F30. Therefore you would need a X 3 barlow. My own preference is the Powermater range which cost a good deal more than most. I also have some time with the Meade Telextenders which I found to be very high quality for the cost. These are now made under the Bresser Logo but My mate the Meade dealer tells me they are the same thing.

So I would get a X3 Bresser Telextender.

Alan.

[StuW]

The Astro Engineering barlows are highly regarded by those that have used them, such as myself.

Sent from my HTC One X using Tapatalk 2

[GlassWalker]

Thanks all. I've got the Bresser SA 3x on order now. I found it interesting while searching, the unbranded 3x I'm using already is also sold as a Bresser! I presume that's another rebadge as a value offering.

[JamesF]

Tele Vue 3x barlows some up second hand from time to time for under £100. An alternative is to put an extension in the back of an existing barlow. With a 2.5x Revelation and 40mm extension I get about 3.3x with my 127 Mak.

James

[GlassWalker]

With the Bresser SA on order with expected delivery tomorrow, I'm not looking at any more options now! I'm cautious about modification by extension since you're pushing the design outside its original intent which typically lead to other degradations. Having said that, my spacing is probably not perfect anyway since depending on the specific camera nosepiece and C-CS extension (or not) that would vary the spacing of sensor to barlow by some 7mm anyway.

On a side note, I have been playing about some more with the 3x barlow output. I think I need revise my original statement to "for an equal amount of time and stacking settings, the X-cel 2x drizzled 1.5x looked better than the unbranded 3x", but using more aggressive stacking options on a longer file I took near the end with the 3x, I am able to tease out more detail than at 2x. But I can't do the same at 2x to compare directly.

[alan potts]

I am sure you will find the Bresser to be good quality. Some say it is a clone of the Powermate but having used both I don't buy into that one. There is no doubt there are better on the market but they come with big price tags. Baader make one at around 400 quid which is a lot of brass.

Hope you enjoy it and post some results if you feel happy with that.

Take care,

Alan.

[GlassWalker]

I don't doubt there can be better, but being realistic, what is the limiting factor of my planetary imaging attempts? First and foremost has to be seeing, and I doubt I have reached the limits of my existing system. However I do suspect there is something to be gained from upgrading the barlow ready for the next chance. The diminishing returns as you pay more makes justification rather difficult. I might still have got a powermate if they made one at 3x, but since they don't, that's a deal breaker in itself.