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7x42 Ultravids and Blackout (1 Viewer)

Marley

Well-known member
I need some help from the optics experts on the forum:

I want to understand which binocular configurations are more likely and which are less likely to cause blackout.

As some of you have seen via another post, I recently bought a pair of 8x50 Ultravids and (VERY sadly) had to return them due to excessive blackout. I can remember ordering them thinking that with a 6.25mm exit pupil diameter my eyes would have more light than they would know what to do with, and yet blackout was still an issue.

Several members have already provided guidance regarding the 8x50s and I really appreciate the help. I would just like to know if there is a general rule(s) one can follow regarding objective size, magnification and eye relief that will generate the least likelihood of blackout.

I ask because I still would like to own a pair of Ultravids and I an leaning towards a pair of 7x42s (I have a pair of Leitz 7x35 BA and love them). I just don't have access to a pair locally and I would like to narrow down candidates before I start the ordering/returning routine with the Internet shop.

Thanks again to all in advance.

This is a truly great forum.

Rgds,

Steffan
 
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Marley said:
I need some help from the optics experts on the forum:

I want to understand which binocular configurations are more likely and which are less likely to cause blackout.

As some of you have seen via another post, I recently bought a pair of 8x50 Ultravids and (VERY sadly) had to return them due to excessive blackout. I can remember ordering them thinking that with a 6.25mm exit pupil diameter my eyes would have more light than they would know what to do with, and yet blackout was still an issue.

Several members have already provided guidance regarding the 8x50s and I really appreciate the help. I would just like to know if there is a general rule(s) one can follow regarding objective size, magnification and eye relief that will generate the least likelihood of blackout?

I ask because I still would like to own a pair of Ultravids and I an leaning towards a pair of 7x42s (I have a pair of Leitz 7x35 BA and love them). I just don't have access to a pair locally and I would like to narrow down candidates before I start the ordering/returning routine with the Internet shop.

Thanks again to all in advance.

This is a truly great forum.

Rgds,

Steffan


Steffan,

I can easily induce blackouts in my SE 8x32, but I cannot with my Ultravid 7X42. I just tried, with and without my eyeglasses, and it's hard to adversely affect the Ultravid view. It has never been a problem in the field.

Best of luck to you.

John
 
Steffan:
I have a pair of Ultravid 7x42s and do not experience any black-out. They are great bins with a wonderful field of view.
Jerry
 
Marley said:
I need some help from the optics experts on the forum:

I want to understand which binocular configurations are more likely and which are less likely to cause blackout.

As some of you have seen via another post, I recently bought a pair of 8x50 Ultravids and (VERY sadly) had to return them due to excessive blackout. I can remember ordering them thinking that with a 6.25mm exit pupil diameter my eyes would have more light than they would know what to do with, and yet blackout was still an issue.

Several members have already provided guidance regarding the 8x50s and I really appreciate the help. I would just like to know if there is a general rule(s) one can follow regarding objective size, magnification and eye relief that will generate the least likelihood of blackout?

I ask because I still would like to own a pair of Ultravids and I an leaning towards a pair of 7x42s (I have a pair of Leitz 7x35 BA and love them). I just don't have access to a pair locally and I would like to narrow down candidates before I start the ordering/returning routine with the Internet shop.

Thanks again to all in advance.

This is a truly great forum.

Rgds,

Steffan


Hello Steffan,

it depends mainly on your own physiognomy (eyes and face and the resulting eye relief in respect of the binocular) whether you are suffering from blackouts or not. The width of exit pupil is irrelevant. But if the effective eye relief of the bins is variable the problem will be smaller or non existant. But this is not necessarily true for all users.
So for a defined bin and a defined user only an individual test can tell.

regards
Walter
 
Last edited:
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