The 75-300mm is a bit weak on contrast. But you can boost this in software (the EF-S 55-250mm f/4-5.6 STM lens would be a nice upgrade. But it does need to be the "STM" version.)
Many of us use Adobe Lightroom and some use Photoshop (I find Lightroom to be much faster and it's also designed to manage organize and manage all of your images as well as synchronize adjustment changes across all images shot in the same condition (e.g. if you shot a lot of images in the same location then you'd want all of them to have the same "white balance" setting.) There's also Photoshop Elements (the entry level version) and full-blown Photoshop CC -- but I find those tools to be more cumbersome to use.
Canon provides an editing/adjustment program called Digital Photo Professional (DPP) and if you haven't already downloaded it, go to the support website for your camera model and you'll see the link to software downloads where you can grab the latest version of DPP 4.
The first image needs a boost in contrast. This is because the "dark" areas in the image are more of a middle gray tone and not really very dark... meanwhile the "light" areas in the image are just a little lighter middle gray tone and not really very light. So imagine you could "stretch" the difference between dark and light areas so that the darks are even darker and the lights are even lighter... this will eliminate that muddy-gray look and the colors look dull (don't touch the colors... just yet).
With a simple editor you could just increase the contrast adjustment and improve the image. But you get more control over how you increase the contrast if you use a tool such as a "levels" adjustment or a "curves" adjustment. This is because the basic contrast adjustment just makes darks darker and lights lighter... but a "levels" or "curves" adjustments allows you to adjust the darks and lights independent of each other (you can decide how much darker you'd like the darks... and then choose how much lighter you'd like the light tones.) You can even stretch each tonal range of the image independent of any other.
As an anaology... years ago a radio might have a basic "tone" adjusment knob. Nicer stereo systems might have a seperate "bass" and "treble" knob. And even nicer sound systems yet might have equalizer sliders which lets you adjust each tonal range of sound indepent of the others. "Contrast" adjustment in photography is a bit like the basic "tone" knob on a radio... but "Leves" and "Curves" adjustments are a bit more like having full equalizer sliders to adjust everything with much more control.
As you fix the contrast you will immedaitely start to notice that the colors seem to be getting a bit of help along the way... the greens wont look so washed out... they'll start to look a bit more vibrant. This is why I don't adjust color saturation until after I fix the contrast problem.
As for the baby picture. Yes, I can see the noise and shooting at ISO 6400 will have that result. Keep in mind that as a photographer you don't necessarily need to photograph a subject where they stand, sit, lay.... you might be able to move a subject to a location with better lighting. If you can do that... it should always be your first option (in photoraphy, having good "light" beats having a good lens or a good camera.).
But suppose there's nothing you can do about the lighting situation. If the subject isn't moving and you have a means to steady the camera (e.g. a tripod) then you can set a slow shutter speed and still keep the ISO low for a better shot. But this is likely not realistic with a moving child unless the child is sleeping. If that happens, cranking the ISO is the next best option and while you will have "noise" in the image, you wont have motion blur (you can do something about noise in an image but there isn't much you can do about motion blur unless you want to try to convince people was an intended artistic effect.)
DPP 4 does have a "noise" reduction slider (as does Lightroom and it's pretty good. Photoshop does... but it's miserable (how the same company managed to write good noise reduction for LIghtroom and miserable noise reduction for Photoshop was a bit of a mystery, but there you have it. If using Photoshop, I purchased a plug-in called "Noiseware Pro" by Imagenomic which does the best job of fixing noise that I've seen from any tool.)
Anyway... you'll usually notice noise is stronger in shadows and less in highlight areas. So tools that allow you to selectively apply noise reduction based on tonal values have an advantage.
The other thing about "noise" and "sharpness" is that they're basically opposites. When you apply noise reduction, the image will usually get softer -- so be careful to apply noise reduction sparingly or things start to look mushy and or skin looks like "plastic" instead of skin in a hurry (not a good look.) When you apply "sharpening" to an image the software looks for subtle changes in contrast (which might represent an edge) and it boosts or exaggerates that difference. The trouble with this is that noisey pixels will look like subtle differences in contrast so when you exaggerate those you really amplify the noise.
As for the video... I'm noticing strong chromatic aberration on the waves -- typically the optical design of the lens is responsible for this and it shows up usally as putting either a red fringe or blue fringe on edges of contrast. Some types of chromatic aberration can be corrected in software but as this is video, I'm not aware of tools that correct this. A higher lens is your best remedy for this issue.
Tim Campbell
5D III, 5D IV, 60Da
