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Opticron Adventurer T WP 8x42 (1 Viewer)


Well-known member
Hi, I'm new to birdwatching and I have just received these binos today:


Problem is: the left exit pupil has a slight indent on the up-right corner (see photos attached or this link for high quality: https://ibb.co/GpD9kWK) and I'm hesitating to send them back on account of optics defect.

Could you tell me what you think about it? If you have the same model, could you tell me how are your exit pupils on yours?
Please note that other Opticron binos have a similar name, these are "T WP".

Thank you,


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Well-known member
I think you are referring to the truncated pupil which is not uncommon; a much more severe case here :

Stephen Tonkin who reviewed the 10x50 version of your binocular found a similar slight intrusion :

I guess on the occasions when your pupil is dilated to 5mm or above you will technically be losing a tiny bit light but unlikely to be of any significance. There's always going to be an element of "sample variation" in optical instruments. Some of these can have a real impact on how pleasureable it is to use. If you're otherwise happy with the view and mechanics of your binocular I'd suggest you've done very well with the sample you have.


Well-known member
Ok I see. I did a short session this morning and I couldn't see any impact on my view, but I'm a rookie. I saw your link, I see it can be much worse.
I think I can keep on with them, I'll wait for more opinions/feedback though.
Thank you for taking the time of answering me, that's nice of you :)


Well-known member
I have the larger Adventurer Porro binocular and rate it less good than a Nikon Action or Aculon.

Part of the truncated exit pupil may be due to the collimation procedure.

Many binoculars have much more exit pupil cut off.
The 12x Optolyth Porros are extreme versions.
Old extra wide angle Porro prism binoculars usually have truncated exit pupils unless they have giant prisms.


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