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SPECS is for SPECULATIONS: Eye relief and Field of View in the Razor HD 11-33x50 (1 Viewer)

Turaco

Well-known member
Can anyone tell me about his experience with eye relief and field of view of the Vortex Razor HD 11-33x50? I know the specifications, but I'm not at all sure they can be trusted.

The background of my question: I've just ordered (and got) a Nikon Fieldscope ED50 with the 27x DS Wide Angle eyepiece (the fixed MC eyepieces seem to be unavailable in Europe). The quality of the scope, optical and mechanical, seems excellent, but there is one little issue: I'm wearing glasses, and to enjoy the full field of view, I have to press them against the eyepiece. Things get a bit better if I remove the rubber "eyecup", but I don't like that feeling of glass(es) against metal.

In theory, there should be no problem: The eyepiece in question has a specified ER (eye relief) of 17,8 mm, and my glasses are rather small and don't stick out much from the face. Besides, my binos have an ER of 17 mm, and I get the full FOV (field of view) without the slightest effort. Whether Nikon's specs are correct here is not the question, however; I could live with that eyepiece, but it's far from ideal.

Now, the Vortex Razor HD 11-33x50 seems to offer an attractive alternative. Originally, I didn't even consider this scope, because most zoom eyepieces have a narrow FOV, and even the best optics are useless if I don't manage to get that bird into the little circle …

The Razor is supposed to have an eye relief of 16-20 mm, and a FOV ranging from 3.6 to 1.8 degrees. The question is: is all that correct? Eagle Optics have 5 customer reviews of this scope on their website, and no less than 3 of these say that the ER is far smaller than specified. One user states that he has to press against the eyepiece to get the full FOV at the higher magnifications - and he does NOT wear glasses! Now, this looks like an ER of 12 mm or less, rather than 16 mm or more (apparently, a Vortex technician has even admitted that the specified ER is quite wrong).

If the specified ER is incorrect, of course one starts to wonder whether this wonderfully wide FOV isn't just another exaggeration - and mind you, Vortex has been known before to give wrong specifications of the FOV, adding up to 0.43 degrees to the true value:
http://www.allbinos.com/137-binoculars_review-Vortex_Sidewinder_10x42.html

So, after this lengthy introduction, back to my question: Could the Razor possibly be an alternative for someone who needs reasonable eye relief and who definitely wants a wide field of view?

Any answer will be greatly appreciated!

Raffaele
 
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The eye relief numbers seem to be correct on mine. Be aware that as you zoom higher the eye relief gets shorter. They finally revised their website to reflect that a while back.
 
Specs is for ...

Hello oldfortyfive,

thank you for your answer.

Meanwhile I've got used to the less-than-ideal eye relief of my Nikon ED50; which means, I'll keep it. However, I've found a simple (and I think quite correct) method for measuring eye relief. The eyepiece in question has 15.5 mm - not 17.8, as specified. That explains why it's possible, but not quite comfortable to use this eyepiece with glasses.

Regards
Raffaele
 
Turaco,

I asked Swarovski for another eye cup for my scope. After it had come I cut the rubber off the original and replaced it with a strip of gaffer tape. I stuck this to an old but clean piece of glass and then cut a hole around a coin. I then removed the tape from the glass and stuck it on the old eyecup. I then cut round the outside with a very sharp blade.

The eye relief was better and the gaffer tape protected my specs.
 
Not sticky?

Hi The-Wanderer,

thanks a lot for your answer.

Actually I had thought about trying something of the kind too, but then I feared that the (sticky) edges of the tape might leave traces on my glasses, especially when it's hot.

But as I said, I've got used to this eyepiece, and when I put my glasses against them with some care (quite parallel and centered correctly) it's all right and I can just get the full FOV.

Regards
Raffaele
 
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