Is It Really Worth The Price Of Admission?

[USMCDOC]

I received the photo adapter for the 883 and I hope to have a chance to play with it this weekend.

how did this turn out?

 

[Turbulent Turtle]

I used my Kowa 883 today at the 1000 yard match for the first time. The IQ is breathtaking. I was playing with the 27X LER. The mirage came out in force after the rain and I could really track it with the Kowa. I am totally pleased with the 883. I will try the PA next time; today was not a good day for that.

 

[6BRA]

If you buy a used kowa, will the warranty transfer? Is there a warranty to a new owner, if not registered to that owner?

 

[Turbulent Turtle]

you know.. from the the literature that is provided by Kowa, they claim that there is no degrading of light coming in from the the objective.. hmmmm

In optics, there are two things that will "degrade" the light going from the objective to the eyepiece.
1- Reflection
2- Amount or density of light.

The first one, reflection, is minimized with coatings. An uncoated lens will reflect back about 5% of the incoming light at every glass-to-air surface. If you have lots of lenses, you can see how that is going to affect the amount of light at the other end. Coatings have reduced the loss to small fractions of 1%. Kowa is saying that their 1.6X booster is nicely coated and won't rob you of the incoming light.

The second one is sneakier, and you can't get around it. The 88mm objective let's in a finite amount of light. Let's say we're using the 25-60X zoom eyepiece. I can't find the exact figures right now, but these should be close. At 25X, the field of view is going to be about 0.9 degrees; let's say about 4 feet diameter at 100yards. When you dial up to 60X, the FOV will be about 0.32 degree; about 1.75 feet diameter. In the eyepiece, the image at 25X and at 60X will be the same size, but the amount of light used to form the same size image will be drastically different and that's why things get darker in a riflescope when you increase the magnification.

Now with the 1.6X booster, your 25-60X will become a 40-96X and yeah, 96X will be about 0.20 degree; or about a foot in diameter at 100 yards.

Do not expect the image to as bright at 96X as it is at 60X.

Conversely, this is also why you do not look at the Sun with a riflescope or any other optic, without using an incredibly dense filter (the reverse of coatings).