What's this texture on my photo???

ladylaura

Hello!

I was a guest at my friend's wedding and couldn't help but take a few shots during their first dance. I used my Canon Rebel XT.

I noticed lines across my photo. :scratch

Yeah, my exposure is a little low, but what would cause those lines? This is straight out of the camera. ISO 1600, 1/125, 4.5.

They are different widths too...some photos the lines are close together, and sometimes they are farther apart. And sometimes they are not there at all! There doesn't seem to be a corrolation with zoom either.

Is it from the high ISO?

I've noticed this on other occassions too.
http://lauramalischkephotography.smugmug.com/gallery/6398003_GcjM3#404846404_yAfmN-XL-LB

ziggy53

ladylaura wrote:

Hello!

I was a guest at my friend's wedding and couldn't help but take a few shots during their first dance. I used my Canon Rebel XT.

I noticed lines across my photo.

Yeah, my exposure is a little low, but what would cause those lines? This is straight out of the camera. ISO 1600, 1/125, 4.5.

They are different widths too...some photos the lines are close together, and sometimes they are farther apart. And sometimes they are not there at all! There doesn't seem to be a corrolation with zoom either.

Is it from the high ISO?

I've noticed this on other occassions too.
http://lauramalischkephotography.smugmug.com/gallery/6398003_GcjM3#404846404_yAfmN-XL-LB

Laura,

I see some banding type lines across their faces. I suspect shutter issues but it could also be lighting related. Were the lights on a dimmer by any chance?

What type of memory card are you using?

Scott_Quier

ladylaura wrote:

Hello!

I was a guest at my friend's wedding and couldn't help but take a few shots during their first dance. I used my Canon Rebel XT.

I noticed lines across my photo.

Yeah, my exposure is a little low, but what would cause those lines? This is straight out of the camera. ISO 1600, 1/125, 4.5.

They are different widths too...some photos the lines are close together, and sometimes they are farther apart. And sometimes they are not there at all! There doesn't seem to be a corrolation with zoom either.

Is it from the high ISO?

I've noticed this on other occassions too.
http://lauramalischkephotography.smugmug.com/gallery/6398003_GcjM3#404846404_yAfmN-XL-LB

It looks like banding to me. Is there any chance for you to post a couple more of the examples to which you are referring - especially if they were taken at the same event? That would help a bit in narrowing it down.

Tee Why

It looks like banding to me, usually caused by interference but you can see it in high ISO, I like to call them pattern noise personally.

Usually with high ISO's, you tend to see them if you increase the exposure compensation in post processing. If this is straight out of the camera without any adjustments (do you have the default Auto corrections turned off if you are using Photoshop?) then I'm a bit surprised by it, but it can happen occasionally.

ladylaura

Thanks for the responses

I posted more photos from the same wedding http://lauramalischkephotography.smugmug.com/gallery/6398003_GcjM3#404846404_yAfmN and left the camera info on to compare.

I didn't pay attention but I suspect the lights were on a dimmer. And I already reformatted my memory card and forgot which one I used for the event. Though, the lines didn't appear on every photo, and were different widths and thinknesses--no rhyme or reason that I can detect.

ziggy53

ladylaura wrote:

Thanks for the responses

I posted more photos from the same wedding http://lauramalischkephotography.smugmug.com/gallery/6398003_GcjM3#404846404_yAfmN and left the camera info on to compare.

I didn't pay attention but I suspect the lights were on a dimmer. And I already reformatted my memory card and forgot which one I used for the event. Though, the lines didn't appear on every photo, and were different widths and thinknesses--no rhyme or reason that I can detect.

The reason I asked those questions is because a dimmer can set up a beat frequency of light variation which can cause a similar effect. It does look like what you are experiencing is too strong for what I was thinking but it might be a contributor. A dimmer can also set up an "electromagnetic field" (EF) static or hum that you can hear on an AM radio and which can effect digital cameras.

A flash card can lose its RF shield, or some cards even have a weak or ineffective shield, and that can induce RF interference into the data being written onto the card. (It happens in the camera before the data is converted from analog to digital.) If the problem only occurs with a single card then I would replace the card.

Test your cards under similar circumstances and settings according to when you noticed the problem occur. Shoot a very plain and neutral subject and then over-adjust exposure and contrast until the problem is evident, hopefully in just one card.

If the problenm occurs in multiple cards then the camera itself is at fault and would need to be sent in for repairs. Do check the flash card socket for bent or missing pins.

ladylaura

Thanks!

What's an RF shield?

ziggy53

ladylaura wrote:

Thanks!

What's an RF shield?

It exists in both the cards and the host camera and it helps to prevent stray radio frequencies from interfering with the delicate electronic signals within the camera.

TV sets have them (the old CRT type anyway) and microphone cables use an RF shield for the same reason.

A pretty good explanation here:

http://en.wikipedia.org/wiki/RF_shielding