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New guy, new Swaros: Comments on CL Pocket, CL B Companion, and EL 8x32 Fieldpro (1 Viewer)

Aotus

Well-known member
United States
Great photo, did you use the Swarovski iPhone adapter? If so what’s it like to use in the field?
thanks! Actually I was just awkwardly holding my phone up to the eyepiece. It's tricky to get a clean picture and more still if I try to use the zoom lens, which turns black after 2 seconds I think because the light sensor is blocked by the position of the eyepiece. The two (and now three?) cameras on the back of the iPhone make me think the swaro phone adapter won't work, but I'm not forking out the cash to confirm.
 
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prc6995

Well-known member
That’s quite impressive for a hand held shot, I assume you must have supported the binoculars somehow. I’m still on an iPhone 7 so only have the one lens, I’ve thought about the Swarovski adapter but you’re right is very expensive.
 

Aotus

Well-known member
United States
That’s quite impressive for a hand held shot, I assume you must have supported the binoculars somehow. I’m still on an iPhone 7 so only have the one lens, I’ve thought about the Swarovski adapter but you’re right is very expensive.
no support, just very awkward and very many discarded shots. I can certainly see how this could lead to camera upgrades and on and on, but I will try to avoid that for a while...
 

tenex

reality-based
I don't know why you [elkhornsun] responded with this (first quoted) post here but I've seen other posts (e.g. the second quote above) you've made about low light and magnification and, perhaps because I'm very new to this level of analysis in optics, your statements don't match what I have understood from other sources... Please help me to understand what I have misunderstood or if I am mistaken in my own understanding...
Remarkable diplomacy... but no, your understanding is quite correct. (Discussion of these issues here is usually better informed.)
 
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Gijs van Ginkel

Well-known member
Elkhornsun, post 16,
Your conclusions suffer from an elementary error.
The diameter of the objective lens does not give you information about the total amount of light leaving a binocular.
A 100x100 binocular would in your calculation be a very bright binocular whereas it is not since the exit pupl is only 1 mm in diameter. If you want to know how a binocular performs: two parameters are essential to predict the amount of light leaving the binocular: the size of the exit pupuil and the amount of light that the optical system transmits and that is determined by : preventing light losses due to reflections by applying approriate coatings and second by using high transmission optical glass to minimize light absorption in the optical glass.
Gijs van Ginkel
 

tenex

reality-based
Whack! (Freud called this repetition complex...)

Gijs, a 100x100 bin would have a whopping 100 twilight factor! It would blow away everything on the market!
(Was it Zeiss who pushed TF as a standard spec for so many years? I thought we were over that by now...)
 
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Gijs van Ginkel

Well-known member
Tenex, post 27,
The twilight factor is not used anymore as a useful parameter to predict the light gathering properties of binoculars and for good reasons.
Gijs van Ginkel
 

tenex

reality-based
Tenex, post 27,
The twilight factor is not used anymore as a useful parameter to predict the light gathering properties of binoculars and for good reasons.
Sorry "blow away" etc was too subtle... should have added ;) ;) ;)

Seriously, whose marketing pushed TF as a spec for so long and why?
 

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