More noise with circular polarizer?

[Ultra Magnus]

The wife and I went down to Carlsbad to a place called the Flower Fields to take some pictures of the kids for her mom. She has some whole thing planned with some particular frames from Halmark that she liked, and the flowers there complimented the frames so there you go. I convinced her that we needed a circular polarizer to prevent the colors from getting all washed out in the bright sunlight, which is one of my biggest complaints after taking a bunch of outdoor shots. Most of the time the sky comes out white and everything esle ends up looking pretty flat. In my tests with the polarizer it made a siginificant improvement (cokin is the brand, $30 at best buy) in boosting contrast and giving everything nice colors. But once we got home after a day of shooting, the shadows in some of the photos looked as if we had the camera set on ISO 400 (it's a Sony DSC-F828, not exactly known for good quality images at higher iso's). The highlights looked good, but in several of the photos, particularly the ones further away and zoomed out, there was significant speckeling and grainy apperance in the shadows, and on the kids faces it looked particularly bad. Could the polarizer have contirbuted to this? They were all taken at ISO 64. I was wondeirng that maybe the filter didn't get along well with the small 2/3" 8 megapixel sesnor... Would that happen on a DSLR, maybe to a lesser extent?

Thanks...

[another view]

I moved this one over to the help forum.

A polarizer shouldn't do what you're describing, no matter what the camera is. Did you happen to take any shots of the same scene without it? Can you post an example?

[DownByFive]

Does your camera have an auto ISO feature that was enabled? Maybe the camera was compensating for the lack of light by upping the ISO or something. Also, the polarizer could have caused your pictures to be more underexposed than normal, contributing to the amount of noise visible. Those are pretty much the only things that it seems the problem could be...

[Peter_AUS]

Polarisers do cut your f-stops down by up to 2 f-stops which is probably what is happening, not enough light getting into the sensor.

[another view]

Two good possibilities above. I know you said you shot at ISO64, but there's always a chance that something changed. I suppose the best way to confirm either of these is to look at the EXIF data and the image histogram.

[Ultra Magnus]

I think I maybe got this one figured... We used the polarizer about the same time we got a new LCD monitor for our computer. I have been noticing that pictures on that monitor don't look as nice as the old big vacuum tube monitor. Everything looks oversharpeneds and pixelated. I also noticed that it doesn't reproduce colors as accurately as the old monitor. It wasn't calibrated either, but looked more natural. The LCD makes things look too contrasty and too bright (I've been playing with the setting and it's better now, but still not as good as even my work computer), and I'm also noticing that the angle at which you look at it dramatically changed the brightness and colors of an image. Should we keep a normal monitor for photo editting? What are your guys' oppinions on LCD monitors in regards to digital photography?

[another view]

Should we keep a normal monitor for photo editting?

From what you say, the answer is yes! I don't have an LCD so I really can't comment on them. I think a lot of people are still using CRT (tube) monitors for photo editing other than some of the high-end LCD's (very expensive). Big improvement with either if you calibrate it though.

[DownByFive]

I'm using both right now (I have a CRT connected to my notebook, mainly for my PS palettes, and so I can watch movies and stuff while editing...) and they both have their benefits. I like my LCD because my pictures look more vibrant and contrasty. At the same time, the pictures do look noisier and oversharpened. Images on my CRT look smoother, but a little darker and not as contrasty. So when I PP an image, I try and get it to where it looks pretty good on both screens. But for prints, I think the CRT look is probably a more accurate representation of what they'll look like...So if you have both, and you have the desk space, you might try using them both at the same time.

[Ultra Magnus]

Thanks.. That confirms my suspicions. Coincidentally, we have a new guy starting here at work next week and the company srung some $$ for a nice lcd. I loaded one of my pics on it, and it looked real nice. I mean real nice. I also didn't notice the contrast or brightness vary when looking at it at off angles. I guess that's the difference between a cheap lcd and an expensive one. Thanks again (everyone) for helping me chase down this problem.