Nasty lensreflection with Tiffen UV protector at DVinfo.net
DV Info Net

Go Back   DV Info Net > The Tools of DV and HD Production > Open DV Discussion
Register FAQ Today's Posts Buyer's Guides

Open DV Discussion
For topics which don't fit into any of the other categories.

Reply
 
Thread Tools Search this Thread
Old March 14th, 2004, 12:27 PM   #1
Tourist
 
Join Date: Mar 2004
Posts: 1
Nasty lensreflection with Tiffen UV protector

I have a PD150 and i'm very happy with it. I bought the Tiffenfilter with it to protect the lens, but this one gives a bad mirror immage of the lens on sunny days.
Can anyone tell me why this is happening, if this is normal and what i can do about it (buy different filterlens, or add a polarisationlens??) I don't even have to face directly to the sun for this nasty mirrorimage to appear. I know that sunflare is normal, but what about this. It's really bothering.
Check it out here:

http://home.hvc.rr.com/debbiestas/With.png
http://home.hvc.rr.com/debbiestas/Without.png

Thanks for anyone that can help me out
Tom Stas is offline   Reply With Quote
Old March 14th, 2004, 01:29 PM   #2
Retired DV Info Net Almunus
 
Join Date: Dec 2001
Location: Chicago, IL
Posts: 6,943
Tom,
Part of what I see in "with" is normal extreme lens flare, caused by the angle of the sun with respect to the axis of the lens. Yes, I can also see the reflection of the lens from the filter.

Lens flare is principally a matter of camera handling and light control. Shifting the camera slightly or flagging the light would have taken care of this in your shot. There are also much subtler versions of lens flare that appear as a haze in the image, when strong lights are allowed to skim across the lens at nearly right angles to the lens' axis. (This is where the flags and wings on matte boxes come into play.)

There are multi-coated UV filters that can help to minimize internal reflections, although none will eliminate them entirely in certain conditions. Shooting in dark conditions with bright point sources often produces a "firefly" effect as the lights' reflections bounce merrily between the lens and filter.

It has become common, and somewhat thoughtless, practice for many people to keep a UV filter on their camera for protection of the len's outer element. Personally, I only use filters when absolutely necessary. If shooting in dusty, wet or otherwise hazardous conditions I will use a UV filter. Otherwise I shoot without one.

I recommend doing some experimention to gain a good understanding of your camera's optical characteristics.
__________________
Lady X Films: A lady with a boring wardrobe...and a global mission.

Hey, you don't have enough stuff!
Buy with confidence from our sponsors. Hand-picked as the best in the business...Really!

See some of my work one frame at a time: www.KenTanaka.com
Ken Tanaka is offline   Reply With Quote
Old March 14th, 2004, 02:27 PM   #3
Warden
 
Join Date: Mar 2002
Location: Clearwater, FL
Posts: 8,287
This a known optical defect that all lenses have. It is covered in our articles here (see number 9, Ghost Images). A better filter will help (B +W, Heliopan) but it will still be present.
__________________
Jeff Donald
Carpe Diem




Search DVinfo.net for quick answers | Where to Buy? From the best in the business: DVinfo.net sponsors
Jeff Donald is offline   Reply With Quote
Old March 15th, 2004, 07:09 PM   #4
Regular Crew
 
Join Date: Jan 2004
Posts: 40
Hi everyone,

Thanks for sharing that information. I bought a multi-coated UV filter for my camcorder in the first week of use to prevent dirt/scratches on my lens. If the UV filter causes this effect in certain conditions, then are there ways to safely clean a camera lens?

I have eyeglass cleaning solution and wipes; can they work?

Also, does modern camcorders have a built-in UV filter. If not then, isn't one necessary in bright light?

Sorry, one more; does a neutral density filter also cause this ghosting effect?

Thanks,
Johann Adler is offline   Reply With Quote
Old March 15th, 2004, 07:26 PM   #5
Outer Circle
 
Join Date: May 2002
Location: Hope, BC
Posts: 7,524
You can pick up a lens cleaning kit from most camera shops. It consists of a bulb-brush, cloth and sometimes a bottle of solution---which I don't recommend. A blow bulb/brush and cloth is all you need.

If I read what you wrote correctly, I suggest keeping the UV on, and not off, use a lens hood, and don't shoot into the light.

Cams don't have built-in UV filters. Why would you what that? The UV is to protect the lens---and what if you want to use a polarizer? You won't be able to get the UV off because it's built-in. Less glass is better, but you also need to protect this glass.

Regarding ND filters: don't shoot into the light. :-))
Frank Granovski is offline   Reply With Quote
Old March 15th, 2004, 09:33 PM   #6
Warden
 
Join Date: Mar 2002
Location: Clearwater, FL
Posts: 8,287
Some eye glass cleaning materials contain silicon and will leave a residue on the lens surface. I prefer micro fiber cloths for cleaning optical surfaces. They can be used wet or dry.
__________________
Jeff Donald
Carpe Diem




Search DVinfo.net for quick answers | Where to Buy? From the best in the business: DVinfo.net sponsors
Jeff Donald is offline   Reply With Quote
Old March 15th, 2004, 10:40 PM   #7
Major Player
 
Join Date: Apr 2003
Location: St. Louis, MO
Posts: 581
Just leave the UV off if that's causing the problem. Unless you shoot in high elevations, you don't need it. I haven't used one in years. Protect the lens? That's what lens caps are for. UV filters are to filter UV.

One of the best lens cleaners is free. Breath your hot breath on the lens and wipe with lens tissue. But just use a brush or bulb to get dust off.
Rob Belics is offline   Reply With Quote
Old March 16th, 2004, 01:58 PM   #8
Regular Crew
 
Join Date: Jan 2004
Posts: 40
Thanks everyone for your advice.
Johann Adler is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

B&H Photo Video
(866) 521-7381
New York, NY USA

Scan Computers Int. Ltd.
+44 0871-472-4747
Bolton, Lancashire UK


DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > The Tools of DV and HD Production > Open DV Discussion


 



All times are GMT -6. The time now is 11:21 PM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network