noise

P

pro.wannabe

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256
Name
michael
Edit My Images
Yes
right i have been trying for years to get to grips with my camera a canon 400D and just when i think i have nailed a shot i get it into ps and get it looking how i like it and the finished artical always seems to have noise in the blacks is there something i am doing wrong?

i try to keep the iso as low as possible 400 or below i can shoot at 800 but if i even try to shoot at 1600 the images are useless and so noisy they just get binned straight away

should i stick to p mode for a while and keep checking the exif to see what the camera thinks i should do?

this is an example i know its not the best image and tbh it looks worse after uploading but you get the point

5773877030_8305827802_z.jpg



full size Here
 
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this shot was at 400 iso 1/800 shutter f14 135mm

all i have done is a light unsharp mask and levels with a 50% crop
 
do you have an unedited, uncropped version to compare it to?

i realised tonight that when i was saving my raw files i was compressing them too much and adding unintentional noise to my jpeg images. so it'd be worth reviewing your workflow to see at which stage the noise is coming in
 
now uploading the original you will see why such a heavy crop lol
 
That first full size crop looks like its got a lot of jpg compression, the second looks much better. But are you increasing the exposure/fill light on these when you do them in PS or LR? or are they as they come out of camera with the exposure, fill light, brightness set to defaults?


I just had another look and it really looks like you are opening up the shadows with fill light/exposure or something and also have the colour noise reduction turned off maybe?
 
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looking back i set camera raw to auto and then fine adjusted before going into ps to finish so the fill light and exposure would have been played with yes

i see the difference and the processing could be at fault but surely that much noise isnt normal and its on nearly every shot i take some more noticable even before processing

that image was taken in p mode aswell
 
pro.wannabe said:
looking back i set camera raw to auto and then fine adjusted before going into ps to finish so the fill light and exposure would have been played with yes

i see the difference and the processing could be at fault but surely that much noise isnt normal and its on nearly every shot i take some more noticable even before processing

that image was taken in p mode aswell
Click to expand...


I just went into lightroom and turned off colour noise reduction completely and then lifted the shadows using fill light and exposure in some images taken at ISO 400 on a D3 and I can get it looking close to what you have there without too much trouble. Throw in the fact that its heavily cropped, some sharping and aggressive jpg compression, especially if you have saved the jpg a couple of times, and yeah pretty easy to do.

I just had a go with your full size file and it look fine if you don't over do the processing.
 
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lensflair said:
I just went into lightroom and turned off colour noise reduction completely and then lifted the shadows using fill light and exposure in some images taken at ISO 400 on a D3 and I can get it looking close to what you have there without too much trouble. Throw in the fact that its heavily cropped, some sharping and aggressive jpg compression, especially if you have saved the jpg a couple of times, and yeah pretty easy to do.

I just had a go with your full size file and it look fine if you don't over do the processing.
Click to expand...

ok thanks i will rethink my processing and maybe spend a bit more time on them and see how it goes
 
It also looks as if it's at least one stop underexposed which will increase the noise levels since you are in effect shooting at 800 ISO.

This is probably due to the fact that you shot against the sky.

In siuations like this it's better to shoot im manual after taking a few shots of the cars on the ground and adjusting to get a good histogram then sticking to that exposure.

.
 
pro.wannabe said:
this shot was at 400 iso 1/800 shutter f14 135mm

all i have done is a light unsharp mask and levels with a 50% crop
Click to expand...

Firstly, by 50% crop I tihnk you mean that you halved the picture width and halved the picture height, leaving you with just 1/4 of the original frame. That means that you threw away 3/4 of the frame or 3/4 of the light the camera captured. That would turn your 400 ISO shot into more like 1600 ISO compared to using the full image.

Secondly, the exposure you have - 1/800, f/14, 400 ISO would be suitable for a scene lit by light so bright that is was 2/3 stop brighter than full, direct frontlighting by bright sunshine. I don't think your lighting was that bright.

Thirdly, I assume you chose to shoot at 400 ISO. The camera chose an amply suitable 1/800 as the shuter speed, but had to stop down way to much, to f/14 to give what it thought was the right exposure. If you'd been at 100 ISO you (or the camera) could have shot at f/7.1 for the same exposure, thus quadrupling the amount of light hitting the sensor.

Given the shot was a bit underexposed you could/should have opened up a little more to f/5.6 or maybe shot at f/6.3 and dropped the shutter speed to 1/640. Had you done that I think your picture would be much improved, even with the crop. So, some room for improvement even with the kit you have now. If you'd had a 70-300 lens or 55-250 lens then you could have zoomed in tighter and avoided the need to crop at all, thus improving things even more.

P mode is all very well if all you care about is a "correct" exposure, but it may not necessarily get that right. The real problem is that it might serve up a combination of settings that really don't suit the subject/scene very well. If it was you that chose to shoot at 400 ISO then that was the starting point of the "problems". It was unnecessarily high for the subject/scene.

Google "Sunny 16". It is a simple guideline for setting exposures in conditions of bright sunshine. If you were familiar with the guideline you would know that an exposure of 1/800, f/5.6 and 100 ISO would have been a good starting point for this scene and you could have set that manually. 400 ISO and f/14 (underexposed) is not where you want to be for this shot.
 
Under-exposure and a big crop = poor sharpness and lots of noise.

You used partial metering, which is risky unless you really know what you're doing - suggest evaluative.

Also, when you looked at the image on the back of the camera, it must have looked dark. That's the time to check the histogram, and apply compensation.
 
HoppyUK said:
Also, when you looked at the image on the back of the camera, it must have looked dark. That's the time to check the histogram, and apply compensation.
Click to expand...

My guess would be that the monster truck only made that jump once, in which case evaluating the image and histogram after the event is leaving things a bit late. Better to get the exposure established beforehand and then be prepared for the decisive moment.

And what if another truck made the jump afterwards, but it was white? Another chimp and adjust on the fly? That's not how I'd do it. I'd be in manual, spot meter off my own palm at +1 1/3 and fire a test shot ahead of time, checking how far I was pushing blinkies on the white boarding in the background, adjusting if need be before the vehicle appeared, not after it had vanished.

Alternatively I'd observe the lighting, see the sunny conditions, figure that the scene was not fully front lit and dial in an exposure equivalent to Sunny 16 (but not at f/16) with perhaps 1/3 stop extra for good measure. Again I would fire a test shot and check before anything interesting happened.

I also probably would not aim for a shutter speed as high as 1/800. I'd want some panning blur and a hint of motion in the wheels too. I'd probably try my luck at something like 1/200 or less - it would probably need less. So, maybe 1/200, f/10, 100 ISO as a starting point.
 
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