bresser sa 4 element barlow.

[rory]

hi all , a quick question. are these bresser s a x2 barlows the same as the telextender /explore scientific focal extender.

http://www.astroshop.eu/bresser-1-25-2x-sa-barlow-lens/p,20888#tab_bar_0_select

anyone experience with them ?

thanks.

[michael.h.f.wilkinson]

For as far as I know, they are the same as the Meade S5K TeleXtenders. I have the 2x and 3x from Meade and they are excellent

[emilf]

I have one 3x and it does the job perfectly, is telecentric and has optimal light transmission without introducing aberrations or distortions.

I use in planetary imaging and i am satisfied with it and I know it is the same as Telextender 5000 Meade.

Here is a picture taken with this Bresser3x SA barlow http://stargazerslounge.com/topic/183550-saturn-2013-from-craiova/.

[John]

If it is the same as the ES Focal Extender it's really good. Russell (russ.will) has kindly lent me his ES 2x FE for a while and it's performed really well. As said above they don't introduce anything other than the additional magnification to the image.

My only slight hesitation is that the Bresser item is still termed a barlow by the dealer, despite having 4 lens elements. Usually dealers are quick to highlight positive selling points in an item and the term TeleXtender or Focal Extender is a bit more attractive than barlow lens.

It does have the same look and feel as the Meade TeleXtenders though so there is a good chance that it's the same or a very close relative.

[russ.will]

I wholeheartedly agree with the above regarding telecentric multipliers and that the Bresser and Meade may be basically the same. However and John maybe able to help out on this one, the Bresser does look a fair bit longer than the ES Focal Extender. Okay, it's hardly exact, but I've scaled the 1.25" barrels of these two pictures to be within a pixel or two of each other and the Bresser looks a fair bit longer:

On the other hand, you don't (significantly) change the multiplication value of a telecentric by varying the setting distance twixt the last positive doublet and the focal point of the EP, so perhaps it is just a stylistic difference, nothing else?

Russell

[michael.h.f.wilkinson]

The Bresser has exactly the same barrel design as the Meade. The ES is different mechanically, but might well be the same optically

[John]

The body of the Bresser one does seem longer although the 1.25" barrel of the ES is a fair bit longer than the Bresser's, as your photo shows.

The TeleXtender / Powermate / Focal Extender designs seem to have a strongly convex lens that sits quite close to the bottom of the eyepiece barrel when it's inserted. There is another lens group someway down the barrel with quite a gap between the two. All the barlows I've used have just had a single lens group towards the bottom of the barrel, even the triplet ones.

If someone has one of the Bresser units it would be useful to know whether it has the strongly convex lens as well.

[rory]

thanks guys. emilf seems confident. i only ask as these are about the cheapest deal i can find .sourcing a telextender 1.25" x2 is proving difficult without paying a premium.

im hopeing to get something to try with these maxvision 68* e/ps once they arrive. ive a 24mm and 16mm on the way and would like to have a 12mm and 8mm option ,but i feel a normal barlow increasing the e/r will not be a good idea. so these four element jobbies seem to fit the bill.

[alan potts]

My information on this from the Meade dealer in Sofia is, it is the same as the old Meade Tele-extender, if that is the case I could not tell the this from a Televue X2 Powermate, which lets face it is not a bad endorsement.

Alan

[russ.will]

thanks guys. emilf seems confident. i only ask as these are about the cheapest deal i can find .sourcing a telextender 1.25" x2 is proving difficult without paying a premium.

im hopeing to get something to try with these maxvision 68* e/ps once they arrive. ive a 24mm and 16mm on the way and would like to have a 12mm and 8mm option ,but i feel a normal barlow increasing the e/r will not be a good idea. so these four element jobbies seem to fit the bill.

From the experience of using my ES FE with the ES82s, I think you will find that the Meade/Maxvision combinations very satisfactory indeed.

Russell

[rory]

thanks russell.

alan ,i think your information could be correct ,i found this while searching.

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I wouldn't mind betting that they are the same as the old Meade series 5000 extenders in a new frock. But I never was one for gambling.

Alan.

They probably are. After all, Meade stopped selling S5k Telextender around the time of the JOC split and they are now marketed in Europe as Bresser SA barlow. JOC owns Bresser so it's a safe bet the telextender/SA barlow were both made by JOC. ES is also owned by JOC, so it's very likely that this new ES barlow will share the same optics as the Bresser SA.

[alan potts]

My you must have been looking far and wide for that one, something from last year I think.

Alan.

[rory]

well the bresser sa barlow arrived today , and have to say it looks and feels like a quality bit of kit. i'll give some sort of feedback once ive had a chance to use it .