Questions for doubler users

AK Troutbum

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I have a pair of 10 x 42 SLC Swaro binoculars, and I'm looking at purchasing a doubler. I'm basically just wondering, for the people that own these, if you are happy with it, and if you had it to do all over again, would you purchase one or not. So what do y'all think, thumbs up or down?
 

ckleeves

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I got one for real cheap several years ago for my el's and only used it several times and then sold it. I just couldn't figure out what it was really good for. When I'm deer hunting I almost always have a spotter, and elk hunting even with 10's I can put antlers on a bull a long ways off.

I'm sure there are some good applications for one but for me personally I couldn't justify carrying or owning one. I think even a mid-grade compact spotter like the minox is a better option and cheaper.
 

Tilzbow

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Had one for a pair of 10x56 Zeiss. Sounded like a great idea. Tried it and found the quality of view was bad and sold it shortly afterwards.
 

Hardstalk

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Ive posted the same question a while back on other forums and the general response was doublers make great paper weights. But thats about it.
 
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AK Troutbum

AK Troutbum

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Thanks to all that responded. It looks like a doubler will not be in my future. I appreciate all the responses.
 

rodney482

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I had one for my El's and hated threading it on....

I now have one for my Razors that just Slips on... It serves its purpose.
 

larryschwartz

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One thing to keep in mind with a doubler, and this might be what folks were talking about with image quality, is that it will reduce your exit pupil/image brightness so you won't be able to use it much during first or last light periods.

10x50 has an exit pupil/brightness of 5, with a doubler it would be 20x50 with an exit pupil/brightness of 2.5. Most folks recommend not going with less than a 4.0 for an exit pupil.
 

Matt Cashell

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One thing to keep in mind with a doubler, and this might be what folks were talking about with image quality, is that it will reduce your exit pupil/image brightness so you won't be able to use it much during first or last light periods.

10x50 has an exit pupil/brightness of 5, with a doubler it would be 20x50 with an exit pupil/brightness of 2.5. Most folks recommend not going with less than a 4.0 for an exit pupil.

That is a good point on exit pupil and magnification, but I think what most are referring to with image quality is a lack of sharpness. I think this loss is the result of using another optic to boost a binocular that has already been optimized for the view at the eyepiece.

On exit pupil, the 4mm standard is a good one for general use binoculars, but using a booster (doubler in this case) really turns the binocular into a little spotter, and a 2.5mm exit pupil isn't exactly tiny by spotter standards (It is like an 85mm spotter at 34X).

I have used a few boosters, and agree the screw-on type are a pain. The Vortex version does what it is supposed to: It gives a quick extra magnification option for a quick look, but it does degrade the image, and I don't like any of them for serious glassing. Even inexpensive compact spotters are going to have better image quality.
 

Racethesunset

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I tried the Vortex doubler on Swarovsion 12x50's. I wanted to like it. To never take a spotter again. The resolution and detail just was not there, even with the doubler on the alphas. In broad daylight, the eye fatigue from the smaller exit pupil was remarkable. I tried to "judge" a tree with the doubler and was slightly more accurate without it. Can you get a closer image? Sure. But the resolution isn't any better. I would be curious how it would work on an 8x42 or 8x50 pair, given greater light gathering.
 
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