Help with exposure

Since I got my KX I seem to get dark photos most of the time. First when I went on holiday (only had the camera a week then) I thought it was me underexposing, then that it was the circular polarizing lens. Now I don't know what to think. I did a 'shoot' for a church meeting last week and fair enough the weather was dull and overcast. I took shots with both mine and hubby's Kx's. Both lots seemed underexposed. I compensated for this by brightening in picasa and made up a collage which I printed out at home to check the brightness. Now I have received the A2 poster the shots are all generally dark in relation to my home print. The printer says they had an enhancement turned on to reduce red eye and they'll reprint without it. This doesn't help the fact that everything I take seems to be underexposed and with both cameras. The Kx does meter through the lens doesn't it? Seems to be fine with flash as I did some shots for work and they have been Ok and even looked alright in the paper! (Fame at last!). I'm just very confused and disappointed. I have viewed all the shots on 3 different monitors and the tv. I have tried various settings on the camera - today I got 2 well exposed shots on Av but the rest were dark.
Any advice extremely welcome. I really don't want to have to adjust every shot I take which is what is happening now even on auto.
I had some cards made up of one shot which showed up well on all my monitors and when they arrived you couldn't see the scene!
Help!
Thank you in advance..... I shall be back to point and click.... BTW I'm using the kit lenses (18-55 and 55-300) I don't think I have the problem with the 100mm macro....

This very strange...
I don't know what it can be.

As for prints being darker, that comes because the screen is illuminated so if you print them out you should brighten your photos a bit so that they match what you see on the screen.

Are you shooting jpeg?
What settings are you using?
Are photos only darker when printed, or also on the screen?

You could try a little exposure compensation and see if it helps. Try bracketing some photos and see which one looks best.

What metering mode are you using?

Right - in order -
When I print the photos at home - brightened or not, from an online printing service, they come up darker (I deliberately lightened this last one to prevent that - I actually thought it would come up too light!)but it still was darker than I wanted.
Shooting jpeg (hubby's is set to RAW+ so I used his jpegs, I've varied settings from auto to P to Av, photos appear dark on the screen too (except for those I've brightened!)
Generally full screen metering which I believe is the default setting although I have tried spot metering.
I just want to be able to be sure that I'm getting a decent exposure such as I was getting from my Fuji bridge camera. They look positively overexposed when I put them next to the Pentax ones. However, they used to print out with no problems.... I just don't know where I'm going wrong.

My camera is permanently set to +0.7 EV as I find Pentax cameras underexpose. I do it with the K10D and did it with the K-7.

Odd... I always find that my Kx in general overexposes rather than unexposeses... (but unexposing is not a problem as there is so much you can pull out of the picture later, but you can't do anything about overexposure!)


We really need to see some example shots to investigate further before its possible to comment further! (with intact EXIF data)

I've spent all evening looking through the pics I've taken with the camera. Apart from the disastrous dark holiday shots once I changed to multi segment metering things did improve. One set of party (outside) photos were quite good especially portraits with the 55-300 lens. The weather was bright and sunny. Once back to gloom - general UK weather - we have the darkness creeping back. The camera basically doesn't like dull or overcast weather of which last weekend was typical. I've used silkypix for this and some numbers seem to come up in red (F number and shutter speed, ISO on some etc.) Can anyone tell me what this means? I've looked through the help files for this but there's no mention of it. I'll try to get a couple of pics up tomorrow so you can see the problem.
I assume the camera should note the effect of the polarizing filter and adjust any settings as necessary if on an auto mode? NB I didn't have a polarizing filter when I had the first problems.
The other difficulty is how do you know what prints you'll get if you are printing out a decent print but the printers send a darker one? How can you prevent this?

Actually it's the other way around, you can get far more from overexposure then underexposure, as long as you don't clip it.

Like Mike, I've also set my camera at +0.7 EV.

Yes because ité TTL metering the effect of the polarizing filter is in it, but be sure to use circular because linear do screw up the metering.
Don't understand this part... but the printers send a darker one, you mean print instead of send?

A few points:

The camera screen is a poor tool to check exposure....use the histogram to check you are correctly exposing.

Can you post some pictures of the ones you are having problems with.

Unless you really know what you are doing avoid spot metering...use matrix.

I am still not sure if you are using raw or jpeg in the camera. If using raw post some pictures with the exposure unchanged in pp.

Finally, is it the image on your computer screen that is too dark or just the prints ?

As flossie said, we need to see examples.

Can I throw something odd into the equation ?

I always found when printing any photos [ HP PSC 1410 ] that if I printed onto Satin photo card rather than Gloss card I had a lighter print - if gloss was used the prints were dark .

I never did solve this - but then that was in my pre K-x time .

Now I don't print as HP have never really fixed the inability to Scan using the PSC 1410 since the advent of Leopard /Snow Leopard.

Sounds to me like some of the problem could be monitor calibration, you really need to post a few of the offending images here, if everyone says "these are OK" you'll know where your problems is.

Sending images to a Lab can be a pain because there is little or no calibration between what you see on your monitor and what they see on theirs, when printing yourself you can have the same problem if the monitor and printer are at odds. (Epson printers have a history of printing dark for example)

The cameras metering system should compensate when any filters are put in front of the lens but a Polarizer is not something you should be using unless its a bright sunny dy and you want to darken the skys a little or saturate colours, remove the filter for day to day shooting.

http://outdoors.webshots.com/album/578650887
The above is the link to my webshots album where I have put up some shots - you get some exif data. Is there anywhere better to put them for better exif?
Generally the shots looked Ok on my monitors although a tad of brightening helped them but on printing (by external print companies) they come up very dark. The two scans of prints received were dreadful too dark to see any detail and impossible to use as greetings cards. My printer prints out exactly what I see on my monitor and I'm happy with that - it's just expensive for lots of pics and you can't go bigger than A4.
I have asked for a calibration chart from one of the print companies.
Thanks for all your help - glad to know others feel the need to over/underexpose routinely! I thought I might have an iffy camera. As I said my Fuji gave nice bright shots in all circumstances.

Just getting 'Page not found' from the site.

Works here but i get