Poor Man's Scope FOV Test

[Denver_AR]

I recently picked up a mid-range scope and was bummed to find it had a noticeably smaller field of view than I was expecting. I started researching FOV specs and discovered it can be difficult to compare specs across scopes due to different zoom ranges as well as limited or incompatible specs provided by mfgs.
I believe it's possible to use the reticle on a FFP scope as a method to indicate FOV as long as common magnification is used. No doubt there's room for error here but I think it makes for an easy visual comparison. If I'm off, let me know.
Starting off, here are reticle pics of my 3 current scopes at 15x & 20x. I used 15x & 20x as I believe these two magnification settings will cover most scopes.

Feel free to add your own but use 15x or 20x to keep results comparable. Putting something translucent in front of scope provided best conditions for camera to focus on reticle.

Tract Toric @ 15x. Estimating a bit less than 12 MRAD from center to edge.

Tract Toric at 20x. A bit over 8 MRAD center to edge.

Vortex Vipter PST Gen II 5-25x at 15x. A bit under 14 MRAD center to edge. Well done Vortex!

Vortex Vipter PST Gen II 5-25x at 20x. 10 MRAD center to edge.

Vortex Viper PST Gen II 3-15 at 15x. Like the Vortext 5-25, about 14 MRAD center to edge.

 

[Birddog6424]

That's the reason I can't stand the Tract Toric. It's like looking through a paper towel roll.

8 mils of visible subtension is anemic at 20x. The XTRIII has at or just a hair over 12mils. And the tube body when you're looking through them is far less thick on a Burris.

I'm a Burris fanboy, so take me with a grain of salt if you wish. But I've had them side by side, and the XTRIII is such a nicer sight picture. I think if folks were able to compare before the bought, an awful ot of people would buy the XTRIII.

XTRIII @ 20x

 

[Denver_AR]

That's the reason I can't stand the Tract Toric. It's like looking through a paper towel roll.

8 mils of visible subtension is anemic at 20x. The XTRIII has at or just a hair over 12mils. And the tube body when you're looking through them is far less thick on a Burris.

I'm a Burris fanboy, so take me with a grain of salt if you wish. But I've had them side by side, and the XTRIII is such a nicer sight picture. I think if folks were able to compare before the bought, an awful ot of people would buy the XTRIII.

XTRIII @ 20x

Thanks for pic from the Burris. The XTR Pro and the Leupold Mark 5HD are top of my list as replacement for the Tract

 

[beetroot]

Thanks for pic from the Burris. The XTR Pro and the Leupold Mark 5HD are top of my list as replacement for the Tract

The Mark 5hd doesn't have a particular good FOV.

The Gen2 PST scopes have some of the widest FOVs on the market, if you are used to such a wide FOV then the Burris XTR 3/pro is probably your best choice.

If you want to compare scope based in the specs take the max magnification and multiply by the FOV spec (for that magnification), this will give you the FOV for 1x.
You can then divide by what ever magnification it is you want to know it for (use the number (3 for example)).

 

[Reload10]

That's the reason I can't stand the Tract Toric. It's like looking through a paper towel roll.

8 mils of visible subtension is anemic at 20x. The XTRIII has at or just a hair over 12mils. And the tube body when you're looking through them is far less thick on a Burris.

I'm a Burris fanboy, so take me with a grain of salt if you wish. But I've had them side by side, and the XTRIII is such a nicer sight picture. I think if folks were able to compare before the bought, an awful ot of people would buy the XTRIII.

XTRIII @ 20x

That’s a lie, unless you got some special version that is better than mine. 20 mils at 20x and 22mils at 18x

 

[supercorndogs]

Its nice when people are specific about what they are referring to. Like answering a comment with three statements with a "that is a lie." Which one do you think is a lie?

Looking at the reticle picture. I see 12 mils of useable elevation marks just like Birddog said. Measured the same way as the OP, from center to edge.

 

[Reload10]

Why was mine only 10? Ocular focus different for me? Set at 20x

His pic is almost 13 mils btw

 

[Reload10]

Specs show it should be 10.4 mils at 20… mine falls right in line with the manufacturer spec.

 

[supercorndogs]

Maybe his mag ring is a little off. Mine is 10.5 at 20x, and looks like his picture at about 16x. I am not sure if they changed anything mechanically with the scopes or if it affected the FOV but they changed them at some point from 5.5-28 to 5.5-30.

 

[stanley_white]

For me, this is all a balance between having enough horizontal MRADs available so I don't have to dial under the majority of the wind conditions I think I will face, having enough field of view to spot impacts, and having the reticle subtensions be large enough and thick enough and with enough daylight between them so they are old-eye and brain friendly and work in as many environments as possible.

Only after I figure out the above, should I then focus on other features of the scope.

-Stan

 

[ChrisAU]

Tested a few I had real quick, no pics.

From center to edge.

ZCO 527
15x 12.2 MILs
20x 9 MILs

Zeiss LRP S3 4-25
15x 12.5 MILs
20x 9.4 MILs

Vortex SE 3-18x44
15x ~12.8 MILs (estimate, tree stops at 10)
20x N/A

Arken SH4 G2 4-16x50
15x ~13.2 MILs (estimate, tree stops at 12)
20x N/A

No, not exactly what I was expecting.

 

[lennyo3034]

Conducting this test is assuming the magnification ring is perfect. In most cases they are just an estimate and minor variation can have a big impact on fov results.

 

[Denver_AR]

The Mark 5hd doesn't have a particular good FOV.

The Gen2 PST scopes have some of the widest FOVs on the market, if you are used to such a wide FOV then the Burris XTR 3/pro is probably your best choice.

If you want to compare scope based in the specs take the max magnification and multiply by the FOV spec (for that magnification), this will give you the FOV for 1x.
You can then divide by what ever magnification it is you want to know it for (use the number (3 for example)).

Thanks for formula!
I had to bust out Excel but formula jives with what I'm seeing through scopes.
Based on Burris specs you're also correct the XTR has better FOV. At 20x should have 11 MRAD center-to-edge.

 

[Precision Underground]

Conducting this test is assuming the magnification ring is perfect. In most cases they are just an estimate and minor variation can have a big impact on fov results.

Exactly this. If you really wanted to do this test, you would need to set your magnification by measuring a known sized target with the reticle on each optic.

 

[Birddog6424]

My bad fellas. I took those reticle pics several years ago, so I'm going to confess to making an error. I thought those were my 20x pics.

I just checked two XTRIII scopes. I had about 10.6 and 11 mils per side on both of them. Variation in the mag ring I suspect.

 

[ma smith]

Good Post OP. Somebody needs to tabulate all of this info into a sticky