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A little help/advice

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#1 Chris_H

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Posted 27 February 2004 - 03:30 PM

I just received my new Obies 20x80 standard today and I’m very impressed! :grin: When I tried them during the day, everything looked good. Not surprising since I asked Kevin if he could check them out before he sent them to me. But when I tried them on Venus later, I noticed that something was wrong. Unless Venus has found a lost twin, my binos are way out of collimation. :bawling:

The image looked like this:

Posted Image

I then took them back in, lit up a wall, stepped back and looked at the exit pupils. They looked like this:

Posted Image

Not perfectly round.

Now I’m assuming I can fix all of this by turning those TINY screws, but how hard is this to do? You see I’m EXTREAMLY good at stripping screws :whistle: and unless I can remove the rubber armour, I’m pretty sure I will do more harm then good... :(

Also, the image in the left tube is hard to focus and looks much dimmer then the right tube...

I really don’t want to send them back if I don’t have to! :help:

Chris

#2 Rusty

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Posted 27 February 2004 - 03:40 PM

Chris,

Try this site for step-by-step collimation instructions:
http://www.oberwerk....t/collimate.htm

#3 KennyJ

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Posted 27 February 2004 - 03:47 PM

Chris ,

I must say that I am VERY impressed by the images you provided to illustrate your problem.

What did you use to produce these ?

Yep it looks like you have quite a marked collimation problem to me.

Good luck with the instructions Rusty directed you to, but it makes me wonder how they got so badly out , especially if Kevin checked them prior to shipping.

Still , not quite as bad as Gary's last week eh ?

Regards --Kenny.

#4 Guest_**DONOTDELETE**_*

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Posted 27 February 2004 - 05:25 PM

Rusty's suggestion is a good one. Also try http://www.cloudynig...-collimatin.htm
before doing anything. I would be make sure I'm completely aware of what I'm doing before messing with the prism tilt screws.

#5 Erik D

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Posted 27 February 2004 - 05:40 PM

Chris,

I share Kenny's comments about your illustrations. I must say I am disturbed to hear about yet another DOA 20X80 S. I have been touting these 20X80 LW/S binos as best vaule in giant binos ever since I received my 20X80 LW a year ago. I still feel the optics are very good but I think I will withold my endorsement from now on until I hear the quality/durability issue has been addressed.

The fact these damages are happening on international shipments is especially frustrating. I know Kevin B will send replacements at no cost to any US customer within a few days. It's much more difficult to take care of our friends from overseas when customs and import duty are involved. I hope Kevin is able to help you reslove this quickly. Good Luck and let us know.

Erik D



#6 Chris_H

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Posted 27 February 2004 - 05:55 PM

Thanks Rusty. Of course I don’t have the right size - ACK! Guess I will go shopping for the world’s smallest screwdriver tomorrow :p

Good old Photoshop, Kenny! ;) I thought it would make it easier to explain the problem by showing it. I was also a little disappointed when I saw the collimation problem, since Kevin had tested it. But then again it’s been traveling a long way and since it’s not protected by anything but bubble wrap and Styrofoam peanuts, I guess you can’t really expect it to arrive in perfect collimation. And as you say, at least it didn’t turn out like Gary's bino!

I've been playing around with the binos for a few hours now and I still can’t believe how nice they are! They don’t weigh anything at all! I was expecting it to be much heavier. The lens covers will fall off after some use and could have been better. But they work for now. The soft case is also ok. It won’t protect anything, but I’m sure its good enough for storage.

One thing I don’t like though is the eye cups. They are really starting to annoy me! I personally feel they are too big and far to stiff. How they are supposed to block out anything is beyond me. Maybe they will soften up over time...I sure hope so.

Still, the Oberwerks are a bargain. In Norway even the Orion 8x56 "Mini Giant" cost more then the 20x80 does – and that’s after the import tax has been paid! The prices are so ridiculously high here, it makes you want to move I tell you! :grin:

Chris

#7 Chris_H

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Posted 27 February 2004 - 06:06 PM

Thanks night watch - I did look at that one as well. After reading it, I’m more scared then ever to mess around with the binocular! lol Wish I had Ed's knowledge :(

I agree with what you say, Erik. Looking back I might have gone for the 20x90 with its braced and hinged objective tubes. But the 20x80's weight and price won. I might regret it, but if I’m careful they should last a while - at least I hope so! :)

#8 Tom L

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Posted 27 February 2004 - 06:13 PM

This doesn't sound encouraging...Can you replace the eyecups altogether? Sounds like if they were sent to you fully collimated, they may need to be checked and adjusted before each use?

#9 Chris_H

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Posted 27 February 2004 - 08:39 PM

I doubt I can change them. I just pulled a little on one of them to see if it moved, but it just pulls the focuser out. I don’t really want to risk anything by pulling any harder.

I do think there might be a frequently collimation issue on these binos. Looking at them now, I can see that you probably don’t have to do much to knock them out. A wee bump against the front when they are mounted is probably enough. The problem with frequently collimation is that you will probably wear out the tiny adjustment screws. If these are damaged, what does one do then? Send them back to Kevin?

Chris

#10 Erik D

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Posted 27 February 2004 - 09:03 PM

Chris,

I'd recommend returning them to Kevin for replacment. Did you pay a import duty/VAT on the way in? If so, can you get a wavier not to pay a second time for a replacement. My company does 60% of our business outside of the USA but we have dealers in Europe to handle the paperwork on warranty returns so the end user does not have to deal with it. You should email Kevin and ask for advice on the best way to handle this.

Time to get some sleep. :-)

Erik D

#11 EdZ

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Posted 27 February 2004 - 09:37 PM

I'd recommend you assess the degree of miscollimation before attempting any adjustments.

Do you normally wear glasses? Do you have astigmatism? If no OK proceed. If yes, do not attempt to even visually test for miscollimation without your glasses.

Are you familiar with some double stars. test collimation on a double star of known separation. This gives you a benchmark separation from which you can determine the severity of miscollimation. The picture you have shown is not useful unless it has a benchmark measure to determine the separation between the two points. There are allowable tollerances. Standards seem to be more than I myself can tollerate, but you could easily have 2 to 3 arcmin of miscollimation and need no adjustment at all. Standards would indicate more.

An excellent double to test collimation is Nu (v) Draco. It has a separation of 62". It's like having a 1 arcmin measuring device in your image. If your collimation is within 2 or 3 times the separation of Nu Draco, you can leave it alone for low power binoculars. You may need to adjust closer 20x and 25x binoculars. For a binocular telescope that allows magnifications of 30x or 40x+, you will most surely need images to be closer.

It's difficult for me to tell what that is in the image you produced of your eyepieces. Actually it looks like a drawing. It is not what I would expect to see from an image of an exit pupil showing miscollimation. Miscollimation would produce a well lit exit pupil with black edges all around. It may or may not be round, as you seem to have shown, but it should have dark all the way around it. (I've gone back and looked at that image again and I think I see that you are trying to draw a picture of what you saw. If so I understand)

If it is determined as necessary to adjust the binocs, the amount of turn on these screws is very very small. You might turn each screw less than a quarter of a turn to reach adjustment.

assess the degree of separation and report back before doing anything.

edz

#12 Chris_H

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Posted 27 February 2004 - 10:48 PM

ED! About time you dropped by :D

No, I do not wear glasses nor do I have astigmatism (as far as I know anyway). My drawings were just a rough sketch to show what I saw when looking through the binocular. I also did the "close the left eye, then the right eye" test and the image did shift. If I centered the star in the right tube, then it would be to the left and up in the left tube (This probably means/says nothing to you). When I then used both my eyes on (lets take Venus) I did see two of them. And they weren’t even close to each other, but quite far away.

You mean v1 dra and v2 dra (Sorry, using Starry Night here)? I'll check it out when the weather clears up again (Which will probably be next month! :p).

Chris

#13 EdZ

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Posted 27 February 2004 - 11:50 PM

Once you've had an opportunity to measure the collimation, we'll talk about which way the screws will move the image. When you watch for two stars to merge and they don't merge, watch to see if they never reach each other in the center, or if each passed by the other in the center. If they go to far and pass by each other, they are converged. If they never reach each other to match in the center, they are diverged.
(I think you got this identified in your last post by centering one and looking for where the other image is.)

There will also be vertical error. Note which one is higher than the other. That drawing would seem to show the images are diverged and left is higher than the right image. But watch closely to see which of those is the left image anfd which is the right. If they are converged images and passed by each other, the assumption based on the drawing could be mistaken.

Screws don't move the image left/right and up/down, they move it at angles. More like the left barrel screw will move the left image from 10 to 4 oclock and the right barrel screw will move the right image from 2 to 8 oclock.

Also check this. Move the image in one side all the way to the very edge. now check the other side and see where the image falls. Is it also on the very same edge? Check Top, or bottom, and check side.

Keep notes so a day after you walk away from doing all this, you have it all noted.

edz

#14 Rusty

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Posted 28 February 2004 - 01:15 AM

Thanks Rusty. Of course I don’t have the right size - ACK! Guess I will go shopping for the world’s smallest screwdriver tomorrow :p

Chris


The best bet for the collimation screws is a jeweler's screwdriver (typically sold in sets). They have a top with a swivel pad, and you place your index finger there and twist with your thumb and other fingers. Jeweler's screwdrivers have straight sided, not tapered, blades, and are usually much stronger for the size than small standard screwdrivers. The blade itself is usually cut to avoid damaging the screw or sliding out of the slot. Hobby shops generally stock these.

Eyecups: If you can get a product called "Armor-All" in Norway, apply that liberally - it will soften the eyecups some.

#15 Erik D

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Posted 28 February 2004 - 06:30 AM

I wonder if correcting the out-of-collimation condition of Chris' bino will take more than adjusting the prisms. The 20X80 Std model have unsupported extra long barrels attached to the prisms housing.

In post #61126 on a different thread, Gary described the threaded sections appear to be 1/8" plastic. It's very easy for such fragile joints to flex given the length of the barrel. I would check to make sure the barrels are screwed in securely first. Also check to see if there is any play if you grasp each barrel and attempt to twist them. Adusting the prisms will not correct the problem if the barrels are out of alignment.

Again I am disappointed by reports of these QC problems. It's a shame because Edz reports the optics of the 80mm std are excellent. Barrel flex is a design issue. Grease on the objective of NEW binos requiring dish detergent to remove is unexcusable!

Erik D

#16 Tom L

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Posted 28 February 2004 - 11:03 AM

They use plastic threading at a strategic point of the binocs? I need to go read that thread.

#17 EdZ

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Posted 28 February 2004 - 02:40 PM

A couple of comments about the 20x80s not pertaining to collimation

I like those eyecups, they are the style I prefer. When not wearing my glasses, I can stick them right into my eyesockets and the conform really well. If i could rip the hard plastic cups off my Pentax 16x60 and trade for those rubber ones on the 20x80s, I'd do it in a second.

I compared the coatings on the 20x80 standards to several other binocs. At both the objective end and the eyepiece end:
They reflect back less light than the Oberwerk 15x70/'03,
They reflect FAR less light than Pentax 16x60s.
They are about the same as the swift Ultralite 8x42.
The Oberwerk BT100 reflects less light than both of these other Oberwerks.
The Fujinon 16x70 reflects just a bit less than all of the above.

Next I did this little test. This is not something I recommend anybody do. This is certainly not a normal test.

The barrels on these 20x80 standards are really long. The body and eyepiece end looks exactly like the 15x70, but the barrels are 100mm longer than the 15x70s. This question of flexure interests me. Could these long barrels have an affect. ??? So here is what i did.

With the IPD set to out to max, twice I measured the distance between the barrels. I got 39.3mm and 39.4mm. Then I took both barrels and literally squeezed them together with the heels of my hands, with greater force than I imagine any binocular should ever be exposed to. I squeezed them down to 35mm. I did this six times. I felt extremely uncomfortable squeezing the barrels of my binocs together. Please don't do this.

After each squeeze, I remeasured the distance between the barrels. I got 39.4, 39.2, 39.3, 39.4, 39.3 and 39.4. So what's this tell me? Unusual force applied to cause flexure to the barrels did not change the original distance between the barrels. Of course, if you were to drop them, I'd put a sure bet you'd see some difference in those results.

Other good binoculars in the mid cost range are made with plastic barrels. It would be pretty difficult to put anything other than plastic threads in a plastic barrel. I'm going out on a limb here, but knowing the 20x80 lightweights weigh less than these standards, I would assume that is the exact means of construction used in that model. Is it the best means of construction? NO. Is it a normal means of saving weight in building a larger binocular? YES. It's not Fujinon quality, but it's not Fujinon price.

By the way, I could not unscrew either barrel with a lot of force.

Just a few thoughts.

edz



#18 KennyJ

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Posted 28 February 2004 - 02:57 PM

Ed,

I must say I was quite surprised to read about you attempting to carry out Grevious Bodily Harm to your Oberwerks.

I think you were lucky not to have caused some damage.

Look what happened when Gary tried it with HIS 20 x 80s :-)

Regards --Kenny.

#19 Chris_H

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Posted 28 February 2004 - 05:44 PM

:o You are mad Ed, just plain mad! I agree with Kenny :grin:

OK! I got some more questions now. I tried the binos again I noticed that things just wouldn’t focus in the left tube. So I racked the focuser slowly in and out (I covered the side I wasn’t looking through) and I found something weird. Sketch time! :jump:

Posted Image

First the left tube. When I focused in, the star turned into an oval shape. When focused out, the image turned into the blob I tried to draw, and it extended down and away from the star. When out of focus (in and out) the image looked really grainy - like a rough mirror.

Now when I went over to the right tube and did the same there, I found something really weird - vertical lines! I have NO knowledge about optics whatsoever, and I've never seen or heard about this before. When the image was focused out, the vertical lines were big at the top and then they got thinner. When it was focused in, the lines where the same size (On the sketch they look really thick. This is just how I made them (Rough sketch remember ;)) They were actually quite thin) and this was also the only time I saw faint diffraction rings.

Now like I said I don’t know anything about optics. If these "effects" are optical problems, I’m very surprised Kevin didn’t see them. Or maybe I just have very sensitive eyes - I don’t know. I think I will have to send Kevin a mail now. Astigmatism and rough surfaces (If that is the case) are something I don’t want in a binocular...

****

Ed, I managed to do some of the things you asked about before the clouds rolled back over.

* The two stars never reach each other to match in the center.

Vertical error:

* The star is higher in the left tube

And yes, the star is at the same edge.

Hope this helps.

Chris

#20 KennyJ

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Posted 28 February 2004 - 06:29 PM

Chris ,

Are you SURE your eyes are O.K ?

From this latest report and set of illustrations it looks to me as if you'd have been better off buying yourself a Kaleidoscope rather than a binocular !

If I were you , the first thing I would do is check that you are not a subject of "Candid Camera".

If not I would be sending Kevin a letter --

-- in a parcel along with the binoculars !

Good luck with this ,

Regards --Kenny.

#21 Chris_H

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Posted 28 February 2004 - 06:58 PM

*Looks around* Well if I am, those cameras are well placed! :D

Well I know my right eye is a little "messed up", but it shouldn’t cause me to see vertical lines! lol

I’m having severe buyer’s remorse right now. I might go for the 20x90 instead. They look like they were built to withstand a RPG attack! :D

They are on the heavy side though...

Chris

#22 EdZ

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Posted 28 February 2004 - 07:18 PM

I am without any explanation for these symptoms, except to say there may be a good bit more than collimation that needs attending too.

It's possible there is some astigmatism. The sign for that is an eliptical out of focus diffraction image that flips orientation as you go from inside of focus to outside of focus.

You've got me stumped with the out of focus diffraction image that is neither round nor oval. You also got me stumped with this lines thing going on.

The collimation thing actually seems rather simple in comparison.

Seek help

(for your binoculars)


edz

#23 Chris_H

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Posted 28 February 2004 - 07:38 PM

I'll send a mail to Kevin tomorrow and see what he says.

Chris

#24 Guest_**DONOTDELETE**_*

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Posted 29 February 2004 - 12:05 AM

Chris, I have been casually reading this thread about your unfortunate problems. That last description is most bizarre! I am utterly baffled. Unless EdZ has some sage advice, I would throw in the towel and contact Kevin about how to advise you...like sending them back for a new replacement. Good luck!

#25 sftonkin

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Posted 29 February 2004 - 01:40 AM

Definitely astigmatism, although exactly where in the binocular it resides is impossible to say.

I wondered if the weird left image might be due to gross miscollimation, with the light-cone through the prisms being vignetted. I'm fairly new (OK, very new!)to dealing with miscollimated binoculars, but I imagine that if it was the objective or eyepiece that was miscollimated, any resulting astigmatism would be masked by the coma that results from the main optics being used off-axis. With the caveat of my very limited experience and knowledge, I therefore wonder if the miscollimation is in the prisms.

The horizontal lines are very curious; I don't recall seeing anything like it before. Chris: What happens to the lines as you approach best focus? Do they merge or do they stay the same distance apart? Does their sharpness change? The reason I ask is that knowing how they behave may help to determine where whatever is causing them resides.


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