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Collimation VS Parallax (2 Viewers)
- Thread starter WJC
- Start date
MiddleRiver
Well-known member
I’m curious: can you explain how collimated bins account for proximity of target? I.e. if bin tubes are adjusted for view at 100m, how do they compensate when viewing object at 1m?
If it’s the wrong thread, apologies…
Ps good to see you posting again ;-)
If it’s the wrong thread, apologies…
Ps good to see you posting again ;-)
Hi Bill,
Interesting question. Interesting article. Got it. Been years since I played with a riflescope, the issue of parallax and how it effects accuracy. Hadn't married the 2 - collimation/parallax. See how some might. You're article steered me clear of that potential. Thanks!
Tom
Interesting question. Interesting article. Got it. Been years since I played with a riflescope, the issue of parallax and how it effects accuracy. Hadn't married the 2 - collimation/parallax. See how some might. You're article steered me clear of that potential. Thanks!
Tom
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William Lewis
Wishing birdwatching paid the bills.
I'll have a go at that, the images overlap, almost entirely at 100m/infinity, very much partially at 1m if you have an instrument with very good close focus - hence the need to narrow the ipd for very close subjects. Your eyes and brain do the rest.
Interestingly the Pentax papillo gets round this ipd adjustment problem by having the lenses slide closer together - towards each other - when focusing on closer targets. One of the reasons it's one of the best close focus binocular optics.
Will
MiddleRiver
Well-known member
I was was wondering if there was a mechanical adjustment - or not.
So, I assume that means binos are collimated when set to infinity and the rest is slightly 'off'? I wonder how much 'off' is ok for the brain and at what point it gets uncomfortable? Noticeable (sort of like RB)? etc.
So, I assume that means binos are collimated when set to infinity and the rest is slightly 'off'? I wonder how much 'off' is ok for the brain and at what point it gets uncomfortable? Noticeable (sort of like RB)? etc.
William Lewis
Wishing birdwatching paid the bills.
Not really- they are always aligned, it's just the overlap that varies with distance so your eyes can point effectively closer towards each other for closer targets and more straight ahead for distant ones- just like when there's no binoculars in front of them.
WJC
Well-known member
When focusing at very short distances, you are focusing INSIDE the binocular. When you do that, necessity dictates you to be CROSSING YOUR EYES. When you do that, YOU ... not the instrument ... is out of alignment. It should be understood that binoculars were designed to bring distant objects closer ... not to bring close objects to the point of scratching your cornea.
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WJC
Well-known member
I will be posting VERY sparingly. I'm tired of being abused for stating truthful things that I haven't watered down so as to make them tolerable to some who are full of opinions but are lacking in facts.
tenex
reality-based
I have just failed to find any such example on this forum, perhaps due to little use of instruments with reticles. Of course you don't find it necessary to encounter anyone actually suffering from an error in order to correct it, but one does wonder how common it really is?
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+1
WJC
Well-known member
Ah, yes, a Trans-Pecos Hombre. Been there, done that, 7 years worth.
WJC
Well-known member
230808
First, I would like to thank those who have been so kind as to appreciate me dropping in recently. When some are beating me down because I don’t think like they do, a few kind words can let me know that I am getting through to those who can be helped. That makes all the sticks, stones, and arrows worthwhile. On page xi of BINOCULARS: Fallacy & Fact I explained exactly WHY I can come off testy to some. While that approach can never change because it gives me the best chance to get through to those who need it the most, that is far from the person I want to be. I have a job to do (self-appointed or not) and that “approach” is a needed tool. I am a 72-year-old stroke victim ... with diabetes. I’m just doing the best I can WHILE I can. Some understand; some do not.
“If you have an important point to make, don't try to be subtle or clever. Use a pile driver. Hit the point once. Then come back and hit it again. Then hit it a third time - a tremendous whack.”— Winston Churchill
Now, to Tenex’s comment. Through my many wanderings through binocularland, I’ve come to see that a good many people use “Parallax” while addressing “Collimation” issues, but if I am serious about raising the bar of understanding, I must be willing to leave the “ninety and nine” to reach the ONE.
Not only do I visit binocular forums: Birdforum, Cloudy Nights, OpticsTalk, Stargazer’s Lounge, etc., but I also address personal emails from all over the world. We are all—including myself—products of our experiences.
I had no idea I would be questioned on this topic by some who thought I was merely talking through my hat and for no good reason. But please understand, if I need to toss myself in the lion’s den to help ONE honest truth seeker, I will do so. (Thinking has never been my strong suit.) Not knowing I would be questioned on the topic, I only found a few references on my computer. They are the first examples to be used in my next bino book. (see attached)
Just how important are optics and binoculars in the eternal scheme of things? NOT AT ALL! But because SOME people think the topic causes the sun to rise, I want to help where I can. I think if those who know what they are talking about would start speaking up more, we could finally shake loose from some of the useless questions and answers that fill these forums to overflowing.
Cheers and Blessings,
Bill
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elkcub
Silicon Valley, California
tenex
reality-based
One wonders why one would wonder. It seemed a rather simple and obvious one to me, having never encountered anyone confused on the subject. (And one wonders why it wasn't simply answered as asked.)
I wonder why you would wonder why another one would wonder.
WJC
Well-known member
230810
Hi Tenex:
I don’t think one would have to look too deeply into Birdforum to see that some of my comments didn’t have time to get their shoes on before you were Johnny-on-the-spot to contradict me, or at least cast distrusts on what I have said. Actually, my last comment was met with much appreciation and approval (attachment #1). Yet, it seems that you think that if you haven’t seen it, heard of it, read it, or experienced it yourself, it must not exist. I find this level of thinking quite shallow, not unlike the fellow (who shall remain nameless) who thinks he can’t trust the pronouncements and findings of professors at the Cognitive Studies Department of MIT (Ph.Ds. all) because ... he “KNOWS” what he sees, when, in fact, he only “KNOWS” what he THINKS he sees. To show my motives were altruistic and my heart was in the right place I created and posted my own graphic illustrating, step by step, how this impossibility was POSSIBLE (graphic #2 attached)
Please don’t get me wrong. I know you could provide a number of posts in which the poster doubts something I have said OR frankly doesn’t like me. It’s okay. Please be aware, however, that for each one you can provide, I can offer 10 in which the poster likes and appreciates something I have said or some graphic I have created for BF or some other Binocular Forum. You see, it all comes down to the level of understanding the individual can muster.
“Any fool can KNOW; the point is to UNDERSTAND.” — Albert Einstein (Falsely ATTRIBUTED but accurately stated.)
For example: I have been chided for using four dots instead of the three when creating an ellipsis or for placing periods and commas INSIDE the quotation marks when needed. Here, too, it comes down to a level of understanding.
People who know what they are talking about should not have to explain their thinking to those who don’t. Three dots in an ellipsis means the speaker is trailing off his or her words. Four dots mean the speaker has intentionally ended his or her words.
Placement of periods and commas in American English should ALWAYS be inside the quotation marks. In British grammar, they go OUTSIDE the quotation marks. Please reference The Chicago Manual of Style.
I know I am up against the wisdom of those who have taken over modern media. However, I will continue to hold my ground.
“The higher we soar the smaller we appear to those who cannot fly.”— Friedrich Nietzsche
Cory Suddarth and I spent much time trying to teach clinical three-axis collimation to our friend Kevin Busarow, owner of Oberwerk. For years, he shared with us that he didn’t need a collimator because, “He could eyeball collimation to 100 power.” We tried hard to teach, but he was not receptive at all.
Do you think he understood the physiological effects of the varying levels of spatial accommodation from one observer to another, or the maximum disparity before the brain could no longer compensate? No, he did not! But, much like you, he thought he knew enough about “conditional alignment being a MYTH” to use me as a promotional tool. To that end he produced video tapes FOR SALE to tell people about the my “MYTH.”
This is what I was referring to with regard to levels of understanding.
Kevin then started using Cory for much of his repair and collimation work. Communicating on a more regular basis, Cory was able to make our teaching stick and then, seeing the need, Kevin bought a collimator and learned the procedure laid out in both of my binocular books (graphic #3 attached). It was also about this time that I was invited by the optical Ph.Ds. of SPIE to address their group on the subject (graphic #4 attached).
But enough about me offering what some members see as dross, it is time for your longevity, experience, and credentials in optics to be presented. So, lay it on us; I’m prepared to be impressed and with the number of times you have disputed and challenged me, I am sure others on Birdforum will be equally impressed. The floor is yours. Please take advantage of it! You have snarled at the volume of credentials I have amassed in optics and binoculars. I will not snarl at you for the same reason.
Cheers,
Bill
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elkcub
Silicon Valley, California
?? Clarify please.
