Help with binocular eyepieces

[TidaLpHasE]

Hi, i have convinced myself to buy a good set of
binno's before i go out and get my scope set-up.

I am looking at the Giant 25x100mm from Andrews, with 45 degree angled oculars.

The eyepieces can be substituted with standard 1.25" telescope ep's, what would be some suitable extra ep's
i could get to match this ?

Also, has anyone had any use with these big 100mm
binno's ? and are they going to be worth the money ?

Will collimation be a problem with these, and how do i tell if the collimation is out of whack ?:help3:

Does anyone know if there is a store in Melb. where i can actually see and hold these? I havn't been able to track any down, so i can at least see them in the flesh before i part with my hard earned $$$$$

Thanks for any advice given.....

[janoskiss]

Andrews has been advertising them for $1400, but try emailing sales@splendourtrading.com.au, the email contact for Saxon (http://www.saxon.com.au). They are Melbourne based and have quoted me a significantly better price on the 80mm ED refractor than anyone else, including Andrews. Transaction remains to be completed, so I'll wait and see if they come through with the goods before giving them any more free plugs.

There is a review of the binos at cloudynights.com: Oberwerk 100mm BT's (http://www.cloudynights.com/item.php?item_id=177&pr=2x48x60).

Just a thought: for the same money, you could buy a 10-12" Dob and a pair of binoviewers, and have chromatic aberration free binocular views of the heavens at over 3-4 times the light gathering capacity of the giant binos.

[mch62]

For collimation and info go here .
How will you know.
If there out a long way you'll know when you look .
If there only slightly out it can bring on head acks from eyestain.
Try to relax your eyes before looking because the mind will compensate and merge the images if there slightly out.
When you relax you eyes when you first look you will see the images not merged but after a short while they may come together.

http://www.oberwerk.com/support/collimate.htm
http://www.binocularschina.com/binoculars/giant_binoculars.html

http://www.oberwerk.com/support/coll100.htm

The latter is the manufacturer of all these.

I have the 80mm Triplets and they needed collimation from new.
I have read this is common with all these Chinese bino's.
Most probably why they are so easy to collimate.

I also have an older pair of Celestron 80mm (Re Vixen Japanese made Circa 1990's) and the quality difference is quite obvious between them especially at the prisim mounts and adjustments.

In 15years I have never need to collimate the Vixens.
Don't expect to much from the Chinese units but they do offer the best bank for you buck if you don't mind re collimating them regularly.

The main problem i have found with the 80mm triplets is the front support bracket that goes around the barrels is only plastic and does bugger all as far as keeping the barrels collimated or supported.
The plastic distorts very easily and is poorly fitted at the junction.
As a result every time you adjust them in and out for inter occular eye distance adjustment they go out of collimation a little bit.
I intend to make some aluminum brackets for them instead.
The Celestron unit (Vixen ) is aluminum and hold the barrels perfectly.

I am amazed at using plastic for this as the central support tripod mounting bar is well engineered and does a good job so why use plastic for the other important part???The weight difference is small.

With the units your looking at the barrel alignment should not be a problem and the prism mounting are better designed .

As far as the optics go there very good in the 80mm triplets any.
Mainly the coatings which are first class at level 4.
Meaning all surfaces including prisms are fully multi coated.
Just be aware that some dealer sell the same Chinese binoculars with the cheaper level 1 coatings.
Andrews defiantly sells level 4.
The Chinese units look better coated than the Celestron's but then the later are 15 years old.

Surprisingly the colour correction from the triplets is about the same as the Vixen doublets but this could be a result of the Triplets being 20x and the Vixen's 11x. Same f4 focal ratios.


The interior flat paint on the Chinese unit is very poorly done and lots of shiny metal can be seen on the inside of the barrels.
This results is some reflections on brighter objects such as the moon but for deep sky does not seem to affect the image.
The Celestron's are very well done and actually have baffels in the barrels.

Any way , I am satisfied with them at only $249 as compared to the Vixens back in the late 80's to early 90's were $600+ and are still the same sorta price now.

Why did i get the 20x80's --- eye relief is important for me these days and the new units are very good in this regard. Also the 20x mag is helpful on some objects.

Hope this help a little .
I intend to do a comprehensive review after Astro Fest between the 2.

P.S. I have seen the 25x100's but have not had a close look at them so can only speculate as to the quality of construction of them .

As far as buying a Dob for the $1400 it depends what ** YOU ** want to do with them but I still enjoy just lying on my back and using Binoculars even after 35 years of telescope observing. They get used more than my scopes at time as there easy and quick to set up when you don't fell like lugging your big scope out. Also can be used for terrestrial viewing . Great for comet hunting ECT ECT.

I did see some one selling the Chinese units in Melborne for a similar price to Andrews but you will need to do a search for them.

Mark

Sorry got a bit of topic and long winded

[mch62]

As far as eyepieces go you will need to carefully select them for the Binoculars so you will be able to come to focus.
The focal plane point will need to be similar as you don't have the focuser travel of a refractor.
Try to get a loan of or go to a star party and try different eyepieces .Even just one to see if it is going to work.

Wide field units like Radian's would be nice if they come to focus and I experimented with my binoculars by removing an eyepiece and holding one of my Radians up.Very nice corrected FOV indead. Radians also work better at shorter focal ratios have a 20mm exit pupil disatance.
The 25x100's are f6 focal ratio I think.

That brings to mind "One Ponders" Binoviewers we tested when he got them , the best eyepiece that worked that night with out the looking down a drain pipe view and the proper exit pupil distance were the Radians.( expensive choice thou)

Mark

[janoskiss]

The 100 BTs are 13 kilos (excl. the mount); about the same as the weight of the OTA of a 10" Dob. So these are hardly light grab-n-go binos. Not sure if you can collimate them yourself. The Oberwerk collimation page does not apply to these one-piece solid body units. These are a lot more expensive than the ones with the bracing & camera tripod mount bar, like the 20x80 triplet or the 25x100FB, so one would hope you'd get that much more for your money, and the basics like collimation and baffling would be well taken care of.

[MiG]

I am very curious about this. I've done Google and Yellow Pages searches and I haven't found any in Melbourne. The ones I have found are made in Japan and are double the price or more.

I'm having a really hard time choosing between 15x70 @ $119, 20x80 triplets @ $249, and 20x80 light weight @ $199.

The light weight ones have quite a good reputation on the cloudynights forums due to image quality and handholdability.
There isn't too much convincing material about the triplets on cn. Also, the Oberwerk triplets are different. They have metal rings at the end of the bar and are nitrogen purged.

I am so stuck.

[TidaLpHasE]

:D Well i have decided to buy these industral sized binoculars, have placed my order and waiting impatiently for their arrival:confuse3:

I can't wait to rig up the block and tackle to mount them on the tripod, high a forklift to move them outside, and work out a hydrolic system to make adjustments:lol:

Why dont these come with a neck strap :doh:

Seriously, i am loking forward to the views i will get of the sky with these huge binnocs, and will hopefully get some time in when they arrive.

I will research a bit more on eypieces to suit these before i buy any, i am thinking about 40-100x would be usable with these ?????

Found a pic to compair the size of these babies with a person in the pic, what can i say.....:scared:

[elusiver]

they big enough for you?? admit it tidal.. u just want them to see where the salmon are from patto before heading out! :P :D ;) u'd probably see geelong from mornington pier with those binocs! :P ;)

seriously though.. could u make a mirror box for those? it'd be a fair task.. but save some neck strain.

el :)

[TidaLpHasE]

Busted:ashamed: o.k. i'll admit it, going to use them to see where the fish are biting lol.

I'm sure you could see Geelong from Mornington with these :thumbsup:

With the 45 degree oculars, i'm hoping that neck strain wont be too much of an issue, even looking at zenith should be comfortable for a resonable viewing time, if not i will restrict looking at zenith and concerntrate on more comfortable angles.

Is it normal to check out the front every 5 minutes waiting for their delivery:D

[elusiver]

NO!

every 2 minutes is the norm! ;) :P :D


el :)

[Starkler]

Are you comming to the Star Camp ? Im sure everyone will love them :D

What tripod are you going to use them on? It'll have to be beefy.

[TidaLpHasE]

I am going to try and get to the Star Camp, at least for a nights viewing and info gathering.

Would be on the Friday and maybe Saturday:astron:

The binnocs come with a military style wooden tripod and mount, i am assuming it's the same type pictured in my previous post.

I might try looking for another tripod, just in case the one supplied isn't too crash hot, one that will hold up all 13 odd kg's.

:doh:How am i going to hide at the Star Camp now?:lol: