Tag Archives: noise

Noise Reduction Update

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A few posts back I mentioned a new noise reduction program I had been using with my GX1 images. The program was Topaz DeNoise and I had a 30 day free trial. Well I’m happy to give an update and I will start by saying I purchased the full edition.

After the blog I got down to the serious business of trying out quite a few noise reduction products. These ranged from OK to quite good but DeNoise was the best for my needs. I must admit that if I was judging this purely on how effectively some of the products removed noise, there were a couple of programs that seemed to match the performance. Unfortunately these were devilishly complicated to use.

The problem most of the programs seemed to suffer is that they had too many tabs and sliders to be adjusted. First I would need to select the range of noise e.g. high frequency, medium frequency etc then I would select the level of reduction for both luminance and colour noise. In addition to this I could target tones (highlights, mid tone and shadows) as well as different colours. Often there were a number of other controls I also needed to play with. These solutions to me are not lightweight and usually left me wondering if I had made the best selection I could. I also wasted a lot of time cycling through all the options trying to perfect the noise reduction.

What I really like about DeNoise is that it’s very quick to use as well as being very effective. Firstly I set the level of noise reduction whilst viewing a mid-tone area of the image. I then look at a shadow area and use a shadow slider to increase or decrease the level of noise reduction in these areas. Next I check the highlights and use the highlights slider to make any further adjustment.

Once I am happy with the noise in these areas I can apply additional colour cleaning noise with another slider as well as using two more adjustment sliders to affect the red or blue channel. What’s great about these sliders is that they all work together. The first slider is enough to achieve good results but the other sliders allow you to fine tune and target the effect.

Once you have applied your noise reduction you might find you have impacted some of the very fine detail. To counter this there is a “Recover Detail” slider which is quite effective. There is also a De-Blur slider which I never fail to be impressed by. This is something that I first came across in the Topaz Detail plug-in and it reduces typical lens blur introduced by camera optics and anti-alias filter. Even with top quality optics and perfect technique, this slider can make a difference. There are a few other sliders to help you really get superb results but this blog was not intended as a product review.

This is a very impressive package that it incredibly easy to use and achieve superb results. Even shooting at the best ISO possible with my cameras, this plug-in will improve the results. Give it a try if you want a lightweight noise reduction workflow that is totally effective.

More Lightweight Noise Reduction

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In a previous blog (Don’t Let Noise Kill Your Images) I wrote about the steps you could take to minimise noise in your images. It’s long been recognised that cameras with small sensors have higher levels of noise than they would if they had a larger sensor as a result of packing more pixels into less space. Whilst there have been great advances in this area, it can still be a problem.

If I look at the images produced by my GX1 (16Mpixels) and compare these to images shot on my GF1 (12Mpixels) both of which have the same sized sensor, I can see real improvements in the GX1 both at base and higher ISO levels. I would say that I am examining the images in great detail for any trace of noise in case you think these cameras are poor performers. To give you something to compare against, when I do this for check with my 5D MkII I can also pick out noise at ISO100 in dark areas and in the Blue channel. So what do you do if you find you can’t avoid capturing noisy images?

In the past I have used a noise reduction tool called Neat Image but to be honest it’s quite a lengthy process to get good results and whilst it has a batch mode, I prefer to fine tune the software to each image (hardly a lightweight processing workflow). This weekend however I decided to download a trial of DeNoise from Topaz Labs and the Noise reduction plug in from PhotoWiz (I already use Contrast Master, B&W Styler and Focal Blade plug-in and rate these highly). The results were a bit of a surprise.

I found both solutions did a better job than Neat Image however the PhotoWiz product took some time to process my sample image, something I want to avoid. Comparing this with the performance of Topaz Labs DeNoise solution I found a huge difference. DeNoise was incredibly fast to process my image but it also gave the cleanest and most lifelike results. Finding the right level of reduction was as simple as moving one slider but it was then possible to further fine tune the results. It gave me lots of control in an interface that was very easy and fast to use.

I want to experiment further before purchasing, but early results look very promising.

LX5 Compact Camera Outperforms 5D Mk II SLR

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It sounds absurd doesn’t it that a little pocket camera costing a few hundred pound could outperform a DSLR costing almost 10 times as much? But that’s exactly what happened to me recently.

I happened to be driving through Somerset with the best part of the day free so I decided to take a detour and visit Wells Cathedral to take some photographs. I had seen some very impressive images of the inside and knew that the Cathedral encourage photography (providing you pay a few pounds for a permit). The only limitation I had to contend with was the low light levels and how to shoot without a tripod.

I decided I could use my 5D with a high ISO setting because of its low noise levels but I would take the LX5 along in my pocket as a sort of backup. With shooting underway, I found I was taking most of my images at either ISO800 or ISO1600 with my lens set to its widest aperture and the image stabiliser turned on. At these settings I was still only achieving a shutter speed of between 1/15” and 1/30”.

As I progressed with my shooting I started checking the LCD at 100% to see if the images were sharp. Unfortunately many of them weren’t, exhibiting quite a bit of noise from the high ISO and some camera shake. I decided to experiment a little with the LX5 and quickly found my favourite low light setting of ISO200 to ISO400 and f/2.8 was giving a shutter speed of between 1/5” and 1/15”. The resulting images did however appear sharp on the camera LCD.

Back at home when reviewing the results I found only about 1 in 5 of the 5D images were acceptably sharp whilst only 1 in 5 (or less) of the LX5 images exhibited camera shake and noise levels on all were acceptable. The problems I seemed to be encountering with the 5D were:

  • Camera shake was evident even though the image stabilizer was on. It seemed much easier to hold the LX5 steady whilst taking the photograph.
  • Because I could shoot with the LX5 lens almost wide open (f/2.8) I was able to maintain a lower ISO setting which resulted in quite good noise control.
  • The lens on the LX5 is f/1.8 and performs very well at this level. Stop it down just slightly to f/2.2 and the performance is excellent. With the Canon lenses (even though they were L series) I need to stop down at least 1 stop to gain good performance.
  • The Canon 5D is a full frame sensor so when used with wide apertures I was achieving very limited depth of field, certainly not enough for the compositions I wanted to shoot. Contrast this with the LX5 which has a small sensor so even at f/2.8 I got great depth of field.

So what of the pixel count difference?

Well the LX5 is 10Mpixel and the 5D 21Mpixel. This means I can realistically print the LX5 ISO400 images at A3+ after a bit of resizing. The 5D produces an image of this size without resizing but what use is that if the images are blurred through camera shake, lack sharpness because of noise or simply don’t have enough depth of field?

Finally I should point out that the LX5 was a joy to use in this environment where as the 5D was heavy, tricky and restricted my photography.

So now you know how it’s possible for the tiny LX5 to outperform the much higher spec and more expensive 5D. The message is know your equipment, where its strengths lie and what its weaknesses are. Shoot in the right way and you can achieve some spectacular results with equipment others don’t take seriously.