Hoping to find a little help. (1 Viewer)

W

wilson13

New member

• Jul 19, 2010

• #1

hi, my dad just gave me an old bushnell monocular. the problem is there is moisture stain in the end lense. i would like it to be fixed and have emailed bushnell. but i am also looking to find out more information of it as well.

this is what reads around the barrel
7 by 25 Bushnell Broadfield 525' field fully coated I-33434 japan (a circle symbol with lines in it).

if someone could tell me more about it, or maybe point me in the right direction i would appreciate it. thanx

 

S

spyglass

Djoo c it? Wut wuzit?

• Jul 19, 2010

• #2

Could you post a pic or 2?

 

S

SG6

Well-known member

• Jul 28, 2010

• #3

7x magnification,
25mm diameter objective lens.
At a distance of 1000 ft an object of 525 ft wide would fill the view edge to edge in the centre. So 29.4 degrees field of view, or about 30.

Personally I would take apart and clean, then reassemble.
But am slightly mad.

 

M

Martin Fagg

Guest

• Jul 30, 2010

• #4

SG6 said:

7x magnification,
25mm diameter objective lens.
At a distance of 1000 ft an object of 525 ft wide would fill the view edge to edge in the centre. So 29.4 degrees field of view, or about 30.

Personally I would take apart and clean, then reassemble.
But am slightly mad.

Click to expand...

Hi SG6,

I don't follow your maths.

I make 525@ approx 10 degree fov.

525'/3 = 175 m/1000m

175/17.5 = 10 degrees
(a rough calc because I don't have a scientific calculator but it's a good estimate)

I suspect you forhot to divide by three so you ended up with the fov three times too big.

Best wishes
Martin

 

J

John Dracon

John Dracon

• Aug 1, 2010

• #5

Wilson, SG6, and Martin - I'm looking at a 41 year old Bushnell Sports Optics catalog from my collection. It shows no Broadfield monocular, but it does show the Broadfield binocular 6x25 with a field of 577' based on a 1,000 yard distance. Believe Sg6 meant to write yards rather than feet. The Bushnell custom 7x26 has a field of 368' at a 1,000 yards. Perhaps the 7x25 Broadfield monocular was made earlier than 1969. John

 

S

SG6

Well-known member

• Aug 13, 2010

• #6

Yep, forgot about the feet and yards mixture. Suppose that metric measurements avoid having to convert.
Must admit that when I did it I was thinking that showing over half of 1000 at 1000 seemed very large and odd.
Just didn't bother to engage the rest of the brain. Must learn to read.