Lower Magnification Futon

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superslack
Posts: 29
Joined: 08 Feb 2016, 23:58
Location: Virginia

Lower Magnification Futon

Postby superslack » 09 Aug 2017, 01:40

Hi guys.

I'm interested in building a lower magnification (3x to 4x) futon type scope to put on a .243 Winchester rifle.

I believe the magnification for most futon type builds is 10-12x and I think that is due to the focal length of the scope's objective lense.

Has anybody built a futon with compact scope to get a lower magnification? If so what was the magnification?

Has anybody removed a scope lens and replaced it with an aftermarket lens of the same diameter, but shorter focal length? I am wondering if I could fit this lens in a 40mm objective lens scope https://www.edmundoptics.com/optics/opt ... nvex-lens/

I want to use a Night Wolf camera since it has a 1/2" sensor for best FOV. I guess mounting the scope may be challenging with the shorter focal length lens.

phoenix
BRUCE ALMIGHTY
Posts: 4357
Joined: 09 May 2012, 14:40
Location: Aberdeen

Re: Lower Magnification Futon

Postby phoenix » 11 Aug 2017, 09:38

I built one using a compact scope - and it came out at around x6
I used an EJ230 camera which was sliding fit inside the scope tube after all the internals were removed
I also tried different objective lenses on a futon build based on a Hawke 3-9x50 scope.
The stock lens in this scope is around 126mm focal length.
I tried 100mm and 80mm lenses in place of the stock lens and found that the 100mm wasn't bad, but that the 80mm was rubbish (very soft focus, and no depth of field)

Cheers

Bruce
LAND ROVER - THE WORLD'S WORST 4X4 BY FAR

superslack
Posts: 29
Joined: 08 Feb 2016, 23:58
Location: Virginia

Re: Lower Magnification Futon

Postby superslack » 12 Aug 2017, 00:59

Thanks for the information. I'll have to get my hands on a compact scope to see if it can be cut short enough to focus on a board camera short focal length lens.

Do you think the poor depth of field was due to the lense or the relationship between focal length and sensor size?

I have picked up one of these for now: https://www.aliexpress.com/item/New-Sta ... .17.ZfTlnD

It's a 50mm F1.2 board lense.

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CustomRifleScopesUK
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Posts: 893
Joined: 21 Feb 2014, 12:39
Location: Medway UK
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Re: Lower Magnification Futon

Postby CustomRifleScopesUK » 15 Aug 2017, 16:19

Hi Superslack,

Many of my builds have been futon type utilising the turrets so it acts just like the normal scope when you need to zero, link here is you need build instructions = http://www.customriflescopes.com/diy.html

i did try a few 4 and 6x scopes with front AO as it has to focus, they were not great as field of view was tight with small diameter AO lenses. The best was 3-9x50 giving me just the right amount of magnification without loosing too much FOV

Hope this helps CRS


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