Problem using polarizer on MX300.

[Jeff Donald]

Last fall I was told by a Canon Tech. Services Rep. that Cir Pols are needed for the XL1 (yes different camera) because of the dichroic prism. This was at a trade show and the Rep. was from Japan and they used a translator to go back and forth (maybe something was lost in the translation). But the bottom line was use a circular polarizer with the Canon camcorders. My best guess is the color problems are caused by a defective filter (not planed parallel, internally stressed, mfg. defect) or the camera has a defect, as dre . . .suggests. So, try a new filter, if problem persists send camera back to Panasonic with images showing the color problem.

Jeff

[Tim Selander]

<<<-- Originally posted by florian otel : Tim,

I have a short question: Since apparently the "Soligor" brand of my circular polarizer is Japanese I was wondering if you ever heard / encountered this brand of filters/polarizers there in land-of-the-good-sushi :) -->>>

Sorry, Florian, never heard of that brand! You mostly get the usual suspects here: Kenko, Hoya, all the camera makers brands....

Tim

[Jeff Donald]

Soligor is a German company and info on them can be found here http://www.soligor.com/index.phtml?sprache=e I doubt the filters are actually made in Germany. I would suspect they are of Asian origin, but I have no direct knowledge of that.

Jeff

[florian otel]

dre,

I've checked the polarizer and yes, looked from the front into a mirror it appears completely opaque.

I'm still waiting for a step-up ring to use it with my camera, but I'll experiment with it "manually".

Any idea on how/if I can (non-destructively) check if the Leica lense on my MX300 are at fault in the way you say ?


Thanks again,

Florian

[florian otel]

Jeff, Tim,

Thanks for the scoop. I should have done a bit of research myself, but since I see a big wide "Made in Japan" on the polarizers, I jumped the gun.

All in all I'll call the shop first thing on Monday and ask for a Hoya instead. Let's see what happens then. In the mean time I'll toy with it and my camera, see if I can reproduce the color shading.

Florian.

[Jeff Donald]

If you can shot a scene with the polarizer, then without, you may see that the color is in both shots. I suspect the problem may be internal with the camera. The polarizer just makes it more noticeable. It's just a guess, but at least it will but your mind at ease over the camera.

Jeff

[florian otel]

Jeff,

Naturally that was the first thing I did, and quite extensively -- different amounts and types of illuminations, subjects, etc. Also, I checked the results in quite a few ways, starting with the viewfinder and LCD and ending w/ my faitful 21'' Trintron monitor. No problems whatsoever w/o polarizer.

[Andre De Clercq]

florian,
A lot of shortcommings can be present in the optical path which remain invisible with unpolarized light. If you coulld remove the lens, the standard way to verify is to keep and rotate polars on both sides of rhe lens. Birefrenfgence can easely be recogniized this way. Also color splitter defects can be verified when , without lens a polar is being rotated in front of the camera.

[Andre De Clercq]

Jeff, I just was reading some post in this thread again. Could you ask the Canon Rep, that if their XL1 camera's color splitting prisms are "sensitive" to linear polarized light (what you get with a linear polarizer), how the XL1 would then react on glas reflections, water reflection, polarized skies...Depending on the camera rotation, the windows would get more or less reflective, the skies would get a deeper bleu... because all this is lineary polarized light.

[Frank Granovski]

The one BIG thing that bothers me about using a polarizer, circular or linear, is that the LCD and viewfinder resolution on my DVL9500 cams are so low that I can't see when they're working, when I'm outside in sunshine! So I twist and turn this way and that, then simply give up and stick my UV back on. Sad, huh?

[Ariel Hershler]

Hm, here is a trick which may help:

Make one red mark somewhere on the polarizer rim. Red nailpolish is great for this. Note that some polarizers come with two rims: one which you screw into the camera, and another which turns with the polarizer glass itself. This allows you to turn the polarizer around without changing the distance from the lens and without loosening it. When you make that red mark, make sure that the red mark is on the rim which turns with the polarizer itself, and not on the rim which turns freely without the polarizer glass.

Note that some (reading) glasses may be coated such that you will be unable to see the polarizer effect at all. In that case you will have to remove your glasses before trying this.

Take the polarizer in your hands, and turn it around in front of one eye, while looking with that eye through the polarizer at the subject exhibiting the reflections or whatever you are trying to remove/achieve, and while closing your other eye. You should be able to find the best position quite easily.

Move the polarizer up or down without turning it, and look for the red mark (you can open your other eye at this point :-) ). Note its position in terms of a clock face (i.e. the red mark is at 7 o'clock, etc.)

Now screw the polarizer on the camera, and turn it until the red mark has the same position. Even if you don't see the effect in the LCD or viewfinder, this must be close to the best position. Usually the polarizer position is not extremely critical.

Try it a few times, and you'll become quite accomplished in this technique.

Hope this helps,

Ariel

[Frank Granovski]

Thanks, Ariel! I never thought of that. Good idea.

[Andre De Clercq]

Frank, I don't think resolution is involved in polarisation visibility. unless you want to shoot a bunch of very small reflective elements (leafs...), and even then, you will see a intensity changing non detailed area when rotating the polar.
Ariel, good idea, but two remarks:
- Don't underestimate the rotational precision of yr polarif you want to cut strong reflection.
- Non metalic coatings have some spectral effects on the remaining, reflected (and polarized) rays, but I don't think there is any effect in "see through" mode (reading glasses). Or did I get you wrong?

[Frank Granovski]

What would you suggest, Andre, to make the polarizing effect visable on my low res viewfinder or LCD? Any tips?

[Ariel Hershler]

Andre, I know from experience that there are some types of glasses which are coated with something which basically already does the polarizing (just like a polarizer filter). So when you look through a separate polarizer and turn it around you don't see any difference. I think also some Polaroid sunglasses have this effect. So I always warn people that they may have to take their glasses off in order to see the polarizer effect.

Ariel