Polarizing Filters On Your Scope ?

[JC_40x]

I noticed the other day that a 39mm polarized camera filter would attach perfectly on the front of my Weaver T-36. Has anyone experimented with any UV, Skylight or other types of filters on their scopes, or would looking through an additional piece of glass hinder visibility ? I haven't had a chance to try it, but I'm going to the range later this week, so we'll see,no pun intended). Thanks,
... J

 

[Preacher]

If nothing else the filters will help keep the scope lens from being scratched or becoming dirty.... You will loose a tiny bit of clarity but not enough to worry about.
A UV filter is your best bet as a polarizing filter will make a image appear to be rather dark depending on the sun angle....

 

[BHarvey]

The polarizer will darken the sight picture about 2 stops, but will increase contrast greatly on some scopes,NXS), and not at all on others,March).

 

[Fred Bohl]

JC_40x

Please see this article Click Here on filters including polarizing.

Typical single linear polarizing filter works by excluding light transmission except for a narrow angular orientation,aka – polarization). Adjusting the polarizing filter rotation angle will vary the apparent benefit primarily by excluding glare from sky glow, water and foliage. Note however that a single linear polarizing filter typically transmits only 30 to 40% of the incident light. A double polarizing filter set can be adjusted to be aligned with each other up to being crossed,90 degrees to each other). A set of polarizing filters used that way will then have combined typical transmission of 35% when aligned to 5% when crossed.

 

[JC_40x]

First, those were 49mm filters, not 39mm as originally stated,if it matters.

Second, Thanks Preacher, BHarvey & Fred. Fred, that was a very informative article on light transmission and optics, I now know I don't know a lot about light transmission and wavelengths,but your article helped clear up a few things.

I went to the range this morning and although I didn't spend a whole lot of time there, I did notice that using the polarizing filter did actually help the contrast and it did darken up a little. It was a hot, very bright day, so the darkening up was not a problem. Had it been a cloudy overcast day, I could see where it might darken things up more than I want ? It did not seem to affect my shooting at all, I still managed to
shoot a whole bunch of 4+1 groups. The one thing that I did notice was that when I used the blue filter in place of the polarizer, I seemed to be more relaxed holding on the target square, in fact I shot the only group today in the ones with the blue filter, everything else was in the two's and three's. I'm sure it was probably a fluke that the best group was shot using the blue, but I'll take it. I never got around to using the skylight or the UV filter, but there's always another day. The good thing about all these theories is that you get to go back to the range and try and prove them out. ... BTW, is there any such thing as a mirage filter ?? Could have used one today.
Thanks,
... J

 

[Fred Bohl]

JC_40x

Under certain sun angles and with adequate target illumination, a linear polarizing filter can help to minimize the form of mirage known as glitter or shimmer so that you can at least "read" the mirage that displaces the target image from its true position.

 

[palma]

How is using the filter different from wearing polarized shades while shooting? Would one expect better image contast with the filter than the shades?

 

[Fred Bohl]

The advantage of the filter is that you can rotate the filter to optimize its angular orientation for the current and changing conditions. The difference in results is noticeable with changing sun angle and particularly in higher cross winds.

I still rarely use any filters due to the loss of available light. The polarizing filters 60 to 70% light blocking makes it only usable in very bright conditions for my small exit pupil scopes and old eyes :,