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Mr Felix
16-03-2014, 8:04am
Folks,

Last night I went out and was taking pictures with Nelly, Greg, Peter and....... (Sorry can't remember all the names).

But when I got home and was looking at the pictures I noticed spots on the pictures.

I took off the lens and looked: Nothing on the front or back, so I looked through the lens.

Zooming in and out I noticed some spots became obvious. Here is an example: (See below)
I'm not 100% sure those are the spots, but looking at pictures these seem to remain constant through out them all.

This muck seems to be "inside" the lens. Bad news I'm guessing.

Also - and I am not happy to say this:

My 550d.
A few times when I was shooting, the camera would go into sleep mode. Fair enough. When I press the shutter button to wake it up, the rear display wouldn't activate.

I hear the camera focus and if I look though the view finder, it was was awake.
What I had to do was press the PLAY/VIEW button and the display would then work as normal.

Sometimes it would come out of sleep mode ok, but sometimes not.

I'm guessing this too is not good news.

Anyone?

ricktas
16-03-2014, 8:11am
sensor dust. your sensor needs a clean. not the lens

have a look at cameracheckpoint

Mr Felix
16-03-2014, 8:19am
Rick,

If it was the sensor, why is it I am seeing specks/dirt/muck when I remove the lens and look though it?

I shall try to work out a way of getting a picture of this stuff I am seeing and post it.

ricktas
16-03-2014, 8:21am
Rick,

If it was the sensor, why is it I am seeing specks/dirt/muck when I remove the lens and look though it?

I shall try to work out a way of getting a picture of this stuff I am seeing and post it.

Dust in lenses very rarely will show up in a photo, unless that dust is quite large. Those spots on that photo are sensor dust.

Also re LCD not coming on, that is how it works. The LCD uses a LOT of battery so it should only be on when you want it on.

Mr Felix
16-03-2014, 8:34am
Rick,

If it was the sensor, why is it I am seeing specks/dirt/muck when I remove the lens and look though it?

I shall try to work out a way of getting a picture of this stuff I am seeing and post it.

I removed the lens and got one of my point and shoot cameras.

Granted it is not in focus or clear, but this is what I see when I am looking through the lens.

It is only visible at certain focus settings too which is also annoying as it was hard to find the right place to set the lens to see it clearly.

And then getting the point and shoot to focus on it... Well, not easy/going to happen.

After several attempts and finally getting the much visible in the picture, here it is.
There are others also, but with the difficulty of getting that ONE in shot and noticeable, I am not going to try and include the others.

Oh the LCD.
Yes, it is only on when needed.
But up until yesterday when I turn the camera on or "wake it up", the LCD would come on and show me the settings.
Putting my face against the camera it turns off. That's a no brainer.
But last night the camera would go to sleep and I would wake it up. NO LCD. The only way I could get it to show anything was to press the VIEW (play) button.

That is NOT how it used to be.

ricktas
16-03-2014, 8:46am
that one single spot in the lens is not resulting in all the spots on your photos. There are heaps. They are dust on the sensor. Rarely will dust in a lens appear in photos, and as you say, you can only see it at one focal length.

Put your lens on your camera, set it to the largest f-stop F4.5/F2.8 etc, then go and take a photo of either a plain blue sky or a plain white object (front of fridge). Upload the photo to your computer and then you will see dust. This is sensor dust.

Dust in a lens tends to result in a more diffused effect and create a blob of out of focus area in a photo, either darker or lighter than the rest of the photo, but generally a bigger area than a small speck like your photo.

Mr Felix
16-03-2014, 9:03am
Ok, thanks.

I shall follow up on what you said.

Though it is weird the number of dots I see through the lens.

As I mentioned the picture is not in focus and there are more visible blobs looking though it.

I guess I shall have to work out what they are at some stage too though. :confused013

Looking at what you said, and what youtube says there are some interesting differences.

You said use the largest F-stop of 4.5/2.8 etc.
Largest in that sense is confusing. Do you mean largest hole size or largest number?
(No I am not being cheeky. Read on.)

Watching the youtube stuff they say quite the opposite:
F16 ISO 100 and a LONG shutter speed.

Yes, use white paper, but when the shutter is open, MOVE the camera to blur the image.
This way: what is "outside" is blurred, and what is "inside" is not.
That way you can see where the dust is.

Anyway, things are progressing slowly and carefully.

ricktas
16-03-2014, 9:16am
http://www.ausphotography.net.au/forum/showthread.php?130169-Dust-what-type-and-how-to-fix-it

phild
16-03-2014, 5:21pm
I agree with Rick it's most likely sensor dust, in some cases it can be oil spots for lubricant in the camera mechanisms.

If there are large spots inside your lens you may well have a fungus problem. If your lens is expensive and has fungus problems, it's important to get it attended to as fungus spores can attack lens coatings and cause permanent damage.

Mark L
20-03-2014, 8:24pm
Just get the sensor cleaned!
Needs to be done every now and then anyway. If spots remain (which they won't) , then worry about the lens.

fabian628
21-03-2014, 8:51am
Rick is right! To see a spec of dust in your lens in a picture you probably need f/10000 and 2000mm focal length :D usually light will just 'bend' around the dust in the lens, if you have LOTS of dust ( I mean like the whole element is covered) you will notice contrast loss. Same with fungus. It takes a lot of fungus to start affecting your images, one strand is usually not noticeable (although it freaks people out to no end).

I usually clean the sensor myself, it is quite easy, you can buy sensor swabs for relatively cheap. I don't really trust the people at the camera shop, and most likely come back dirtier than before. Getting the sensor reasonably clean is important for macro especially where high magnifications can cause very narrow effective apertures. :)