Mar 18

(Download pdf version)

When you have to use high value of ISO in your photos it's sure that you'll have some noise problem, also using full frame camera. But in post-production it's possible di reduce this aspect. Photoshop CC has two filter in order to reduce the chromatic noise: 

  • Reduce noise
  • Dust and scratches

Reduce noise filter

We start with this image; how you can see the backgroud is a bit grainy (click the picture to zoom in)


but with the reduce noise filter we can get this situation: using the filter setting of the picture the noise background is less then before, but it's already a little bit visible.



Dust and scratches


With this filter is possible to get a very soft background, in fact with only a radious of 6 pixel the chromatic noise is cancelled.



Now is better to explain one thing: these two Photoshop filter are very useful and you could get some very interesting results in order to remove chromatic noise related at high ISO, but they have to be contextualized to the photo because in some case is better to use the first filter, and in other cases is better to use the second filter. Futhermore if you printed your photos, in the most cases you coudn't see the chromatic noise, so that work could be unuseful, instead if you publish your pictures only on the Web, so it makes sense.

Second thing. In this short tutorial I worked with different copy layers: one for the background and one for subject that I have cutted out with some Photoshop tools in order to get a better job, and to compare the photo before and after the filters application.

My advise is to try with the first one filter, and if the result aren't so good so try with the second one, but Always working with the layers.



Sep 17

(Download pdf version)

Time ago I found a new way to make more sharpness an image using lab color method in Photoshop CC 2017.

The first thing I do is adjust basic parameters with Lightroom CC 2017:
...and after (the red box indicates the modified parameters):
then I open the image with Photoshop:
I now perform several functions as follows: duplicate the main layer
and then I convert it to an advanced object (the icon layer changes...):
After I open the advanced object layer with a double click on the icon and I convert the image in Lab color...
Now I select the Chanel tab and the Luminosity layer (see the red box...): the image becomes black and White...
Then I make a selection with CTRL+click on the Luminosity icon of the Lumonosity layer and I invert the selection with CTRL+SHIFT+I.
Now we can apply the sharpness filter two times...
the first with the following parameters: 200, 1, 2
the second with the parameters 50, 20, 2.
Now you have to save the image (CTRL+S) and close the advanced object image with the following result:
The 100% zoom with the sharp lab mask...
... and without.
Because the mask is too strong I prefer to shade a little bit about 50% (see the red box at opacity option):
Now we have to reduce the general noise, so we create a selection with Quick selection (with this tool I select some vegetation on the left...) and Polygonal selection tools for refinement, and...
... than create a new layer with copy&paste the selection.
The next step is to reduce the noise of the middle layer with Noise reduce tool:
Reshade the first layer at about 50% of opacity for the final result.
I hope you enjoy with this tutorial and see you soon!!


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  • Shooting live music with the Panasonic Lumix GX9


    85mm | ISO 200 | 1/2000 sec | F2.8

    The South Lake Union Block Party is pretty standard as far as block parties go these days; loud music and expensive beer in a vacant lot in the heart of Seattle's South Lake Union neighborhood. Over the course of putting the finishing touches on our full review of the Panasonic Lumix DC-GX9, I wanted to get some real-world autofocus experience to put our more formal testing into better context.

    So, on a hot and hazy Seattle afternoon, I took the GX9 and Lumix G Vario 35-100mm F2.8 lens down to see the band Acid Tongue, and exclusively used Touchpad AF and Tracking the entire time. Here's what I found.

    All images in this article were shot with the GX9 and Lumix 35-100mm F2.8 and are processed in Adobe Camera Raw.

    Tracking technique

    47mm | F2.8 | ISO 200 | 1/4000 sec | F2.8

    Touchpad AF on the GX9 allows you to drag your finger around the screen to move your AF point while the camera's viewfinder is up to your eye. This is great for quickly moving around a single area, but I also found it's a great way to take advantage of the sticky AF tracking that the GX9 is capable of.

    Firing off single shots, I was really impressed at how consistently in-focus my images were

    If you're using tracking while composing via the rear LCD, you simply tap on what you want to track; to disengage tracking, you have to hit the 'Menu / Set' button, or you can tap elsewhere on the screen to track another subject instead.

    When you use tracking with the electronic viewfinder, you can use Touchpad AF to move the area over the subject you want to track, and half-press to initiate autofocus. You can then re-compose at will, with an AF box tenaciously tracking your chosen subject. Firing off single shots, I was really impressed at how consistently in-focus my images were.

    100mm | ISO 200 | 1/4000 sec | F2.8

    Since you can't simply tap the screen to change subjects when using the electronic viewfinder, I found another way of working: dragging on the rear screen automatically disengages tracking, and once you place the area over a new subject and release your thumb, it begins tracking that new subject. Pretty neat.

    While you may be able to get similar results by just moving a single area around with the Touchpad and ignoring tracking altogether, I tend to like using tracking in these scenarios to allow me more compositional freedom - and if the subject moves erratically to another point in the frame, the camera will help me keep up and get more images that I wouldn't have been able to get otherwise.

    It's not perfect

    51mm | ISO 200 | 1/1300 sec | F2.8

    As always with autofocus tracking, there are times when it doesn't quite work. When subjects move from bright light to shadow, the tracking algorithm can sometimes get tripped up and shoot off to the background, or simply fail to focus on anything at all. Additionally, there is some shot-to-shot lag in the GX9 that can make it difficult to follow your subjects.

    The GX9's keeper rate is significantly higher if you shoot single images as opposed to bursts

    So why not simply shoot bursts then? Well, we've found in our testing that the GX9's keeper rate is significantly higher if you shoot single images compared to bursts (stay tuned for the autofocus page in our full review for the details). So I made a call to take the shot-to-shot lag and impressive focus accuracy over shooting bursts with a lower hit rate.

    The wrap

    100mm | ISO 200 | 1/1600 sec | F2.8

    The GX9 was a really good companion for this type of event. Paired with the Lumix 35-100mm F2.8, I had a compact, responsive package that wasn't all that conspicuous, but I had plenty of reach and ended up with far better image quality than, say, a 1"-type superzoom. Of course, this combo can't quite match up to a full-frame DSLR and a 70-200mm F2.8 lens, but that's not really the point here.

    Sure, the GX9 wouldn't be my first choice for critical, action-oriented work (and Panasonic makes higher-end models for that sort of purpose anyway). But for the casual user who wants a small, stylish camera and wants to occasionally photograph a concert or sporting event for fun, the GX9 is easily up to the task.

(C) 2018 Giuseppe Gessa