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Paulpp
28th January 2008, 02:28 PM
Just tried the Cokin filter on my E3 - not the best of subjects etc., but to see what happened.
Not sure where the "rings/flare" came from. Noise much much less than my E400. No doubt more post processing would help, but others views/suggestions/experiences appreciated.
First is straight shot 1/250 @f9
Second with filter 1/5 @ f3.5
Third is second with zero saturation
For some reason can't get the link to show here, but they are in my gallery

Ellie
29th January 2008, 01:03 AM
It's interesting to see those results.

I can see the concentric rings on the mono version, not quite as obvious on the red one.

Did you use just the IR filter, or were you using a daylight UV filter as well? Could they be a reflection of the innards of the lens?

Paulpp
29th January 2008, 07:57 AM
Good point, as there was a UV filter as well. Will try again without the UV filter.

John Anderson
9th November 2008, 03:17 PM
Had a look at your IR image. Definately flare. Remove any additional filters. Incidentally, I use an Oly c-2020 camera, which is extremely sensitive to infra-red light and has extended response in the ultra-violet region. You should be able to find one cheaply on EBAY. The only problem may be sourcing SmartMedia cards. Let me know how you get on. Best wishes, John.

Dicky
9th November 2008, 05:03 PM
i use an olympus C4000z for my infra red pics and it works really great :0 wouldnt it be nice if olympus were to do an infra red specal like fuji do
i havent had much sucesss with my E300 slr yet but will try again soon

photonutter
9th November 2008, 06:35 PM
Think if I remember correctly this has more to do with sensor size and its uv filter. The larger the filter on the chip, the more reflected light bounces back out to the infra red filter on the lens and in turn back to the sensor, concentrating in the centre of the beam. The only real way to get around this is to have to chip filter replaced, a bit drastic for a new camera, maybe a cheap second hand converted body or stick with the smaller camera? The other alternative is to try and use this as an artistic enhancement?

photonutter
10th November 2008, 08:54 AM
Not sure if the E3 has this but just remembered out the frame edge shading option on the E500 hidden away in the menus. On mine it's in the playback menu under SHADING COMPENSATION. Could be worth checking.

jucca
10th November 2008, 09:24 AM
I just got Hoya R72 IR filter. I read somewhere that it needs 1000 more exposure with IR filter. Didn't have time to play with it, but here one picture taken from my window, rainy day, 60sec. Sligtly croped, B&W conversion in PS, taken with E-510/14-42mm


http://i34.photobucket.com/albums/d124/jucca_vtr/IR_test.jpg

John Anderson
10th November 2008, 12:08 PM
That's a good IR image, the chlorophyll in the vegetation reflects IR light efficiently, hence the white foilage. A few years ago it was possible to buy a Kodak film called IR Ektachrome. This 'false colour' emulsion was developed during the Vietnam war to detect artificial camoflage. A yellow filter was fitted to the lens, and natural foilage recorded red, synthetic foilage (camo) various shades of blue-green. Has anyone ever used it?

A 60sec exposure time indicates that the camera has in-built IR blocking filter. The early Camedia cameras didn't, so allow capture of IR images with short exposures. Unless you have the IR blocking filter (called a 'hot mirror') removed - there are a couuple of companies in the U.K. who will do this - long exposures are the norm.

Best wishes,

John Anderson.

ndl0071
10th November 2008, 01:16 PM
I don't have a great deal of experience with IR but the following link is a good start for people interested.

http://www.wrotniak.net/photo/infrared/e510.html

Ellie
10th November 2008, 03:29 PM
You might like to look at this photographer's work http://dabi.shutterchance.com/archive.php for some astonishingly good IR pictures.

The Wrotniak article is a good starting point for learning about IR.

I wonder of Olympus technology is actually hampering these sort of pictures though, because the cameras have an effective IR filter? I don't know enough about the physics, so please excuse my ignorance.