Objective Lens filters - is clear glass available?
Posted 18 July 2004 - 09:07 PM
"TIFFEN 58UVP -- The Haze ( UV ) filter improves your pictures while protecting your lens from dust, moisture and scratches.
o Can be left on the lens at all times for protection
o Corrects for Ultraviolet ( UV ) light which can register on film and videotape as a bluish cast, obscuring distant details "
Is this what I want? Doesn't someone make a plain glass (like a UCL) lens for this purpose? What's the best choice?
Thanks in advance,
Posted 19 July 2004 - 02:12 AM
Are you sure yours does not have them? If not the UV haze filters would have to be the ideal ones short of a transparent multicoated cover which I am not sure exist.
Are the UV filters anti-reflection multicoated?
Posted 20 July 2004 - 01:30 PM
I thought about using conventional "slip on" type lens caps, but the barrels of these binoculars are quite large in diameter and have sort of a tapered shape, so I am not sure how well they would work. I don't know where to shop for some, in any event. And I dislike having them loose and needing to keep track of them.
As an alternative, has anyone tried a "fast cap" that hinges open and shut? I might consider something like
Thanks again and cheers,
PS -- I am loving these binoculars!
Posted 20 July 2004 - 02:28 PM
Congratulations on getting yourself a binocular you have already described as being wonderful , spectacular , and an object of your love.
I know and appreciate those sentiments.
I am less familar with the idea of using a "permanent transparant covers" of some sort through which to look , and am not convinced this will not affect the image quality adversely.
In fact I am pretty sure that they WILL degrade the image.
Of course , I am no stranger to being proved "wrong" !
If you can ever bear to take the risk of removing these covers for a few minutes sometime , I would be very interested to learn of your HONEST opinions about what , if any , differences you might notice between "with" and "without" covers.
Enjoy your 15 x 50s -- and do keep in touch.
Regards , Kenny.
Posted 20 July 2004 - 07:26 PM
I am not that familiar with using filters on binoculars.
However, it is very common on cameras. The reason being that film is sensitive to UV and will give photos a bluish tint if a large amount of UV light hits the film. Often there is no real discernable affect of the filter when there is low UV levels (although some will dispute this). So many people fearing scratching a $250-$3000+ lense will purchase UV filters and use them as protection against stratching the lenses (they save one of my lenses). On digital cameras the CCD element is sensitive to IR and an IR filter is usually built into the camera.
However, I would guess the filter would make more of a difference in astronomy since light levels are much lower then in most photography (and exposure time can be increased for photography when it is not) . However the drop off should be minimal. However, if the user can not tell the difference then why not use them.
Although if the threading is the same as on a camera then I am curious why a pair of camera lens caps would not do what avusblue wants.
They also sell polarizing and other types of filters such as haze-reducers and color filters. I wonder if any of those type filtes would help increase contrast of some views similar to lunar or nebula filters? would interesting to see.
Posted 20 July 2004 - 07:36 PM
Nikon 58 MM Clear NC Glass Filter and Hoya clear glass filter are two that I know of. They are multicoated to reduce reflection and ghosting. They are both around $34 a piece.
You can also get Hoya or Nikon UV filters they are also multicoated and claim to transmit 99.7% of light.
The Tiffen filters are cheaper at about $12 and they make a clear filter, but I am not sure they are multicoated which means they will reflect more light (if not multicoated).
My guess is the Tiffens are not multicoated do to the price and the fact it is not listed in any of the specs I can find.
You may want to also see if crystal or sun-pak filter carry clear glass multicoated lenses. They may be cheaper then the Hoya or Nikon.
Posted 20 July 2004 - 08:05 PM
But I'm surprised the Canons didn't come with caps - I'd snoop arounf the 'net and see if they're not standard...
Posted 20 July 2004 - 08:25 PM
The regular 58mm camera caps work on them, but are hard to use with the rubber cover. I would guess that would be the best idea or use a cheap set of screw on glass filters that you take off. If I paid that much for a pair of optics I would not want to reduce to optics by adding extra lenses. If you want to leave the lenses on I would purchase some high quality multicoated lenses. JMHO
Posted 21 July 2004 - 10:52 AM
2) I did also order the "snap on" style lens caps to try both with and without the filters.
3) It certainly is possible that I will find a noticeable diminuition of image quality. I will closely check for this. If so, I will go without the filters at night and only use them during "high impact" type active daytime use.
4) I will certainly report in with additional observations and learnings when I get the filters and give them a good try.