Problem with new binoculars
Posted 10 February 2004 - 03:58 AM
Posted 10 February 2004 - 06:22 AM
Is this a question? Are you seeing this in a binocular? OR are you describing a problem for someone?
Please just type a few sentences more so we can understand the meaning of this post?
Posted 10 February 2004 - 07:00 AM
It is a question
The problem is present in my new binoculars 22x100. The collimation is ok, but the circle of escape in the left eyeglass is oval and much diffused light is present, the image is less cutting that in the right eyeglass.
I am estimating if to render behind the product, or to make to arrange it. I repeat the collimation is ok.
Posted 10 February 2004 - 10:00 AM
The condition you have clearly described may come about if the images are brought into conditional alignment but the barrels are not aligned in mechanical axis or the lenses within the barrels are not aligned to the optical axis. In this case what may have been done is this.
Assume one of or both barrels or main objective lenses is not aligned to optical path.
Images appear not merged.
Collimation screws are then adjusted on one side to merge images. Conditional alignment of images is achieved.
Now one exit pupil has a distorted shape. It is no longer round, but appears oval.
What Is Wrong Here?
In order to achieve conditional alignment between two tubes where one or more elements in the optical path are not aligned with the optical axis and mechanical axis (other than a prism), the only available adjustment to the end user is to adjust a prism tilt screw. This will provide you with a merged image, a conditional alignment, but in effect may make a bad condition worse.
You may now have a binocular with elements not aligned with optical or mechanical axis AND tilted prisms. In effect this has changed the shape of the exit pupil. This is showing that the light path is off-axis in this barrel. But, it required tilting the light path to see a merged image. This was done by tilting a prism.
This is a perfect example of a situation where adjusting prism tilt screws can merge images but not correct an out of alignment optical axis. If something other than the prism was initially responsible for the images being NOT merged, and it required a large tilt of the prism to get a merged image, a conditional alignment, the condition will manifest itself by showing an oval exit pupil.
There are a number of conditions that may produce a similar result. It is possible that too much adjustment was made to one of the four prisms. It is possible that the wrong barrel was selected for prism adjustment. It is possible that the condition I describe above is the cause and no matter what you do you will not get rid of the oval exit pupil.
There are too many possiblities to figure which may be the cause.
You may need professional help to determine the cause. If you adjusted the prisms and created this situation, try to follow every step you took back to where it was before you did anything. Then procede with care taking note of every move you make. If this condition exists in a NEW binocular, contact the vendor.
Here is an article with a full discussion of the topic.
Posted 10 February 2004 - 12:45 PM
I have sent the binoculars in repair not to the vendor.
The technician has telephoned to me saying to me that the problem is in a bad alignment of the optical centers, like has said you. The binoculars is collimated but the optical centers of all the optical elements are not center.
The repair has a high cost, but task to maintain the binoculars.
The binocular is a Oberwerk 22x100, and would too much cost to send behind the product.
The technician says that once repaired and aligned on collimator laser, the binocular is ok.
Posted 10 February 2004 - 07:36 PM
I realise there are at least two types of "obligation"
i.e legal and moral, but surely cases like this can only be at best, bad press for both manufacturer and vendor ?
Does anyone agree - or am I just being prudish , old -fashioned -- or perhaps worse still, terribly British ?
Posted 10 February 2004 - 07:53 PM
Posted 11 February 2004 - 07:18 AM
My thought is:
Kevin is a good person, task that replaces without problems,
but these are binoculars of low cost,( Not there is the quality control in China ) if I replace it, who says to me that the new binocular one is perfect?
I live near al more better constructor and repairer of telescopes and binoculars in Italy.
The repair has a cost, but I have the certainty of having binoculars perfect, with perfect optical centers, and collimated on bench laser, with quality certificate.
The technician says... un good binoculars (Zeiss, Leica, Fuji etc...) 30% of its cost is only for the perfect collimation!!!!
This is the only binoculars that I have, made in China
......and last binoculars made in China that I buy
Posted 24 February 2004 - 09:08 AM
I have made to repair the binoculars (hour the optical centers are coinciding, in all the optical elements) the pupille of escape are circular, and the resolution of the binoculars is a lot the much best one. Hour the stars are stung of pins, and I do not have more diffuse light.
This is a very good binocular.
Posted 24 February 2004 - 12:50 PM