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Replacing Sky Against Sea With Photoshop Quick Selection Tool


Witterings

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Hi,
1st post in here so here goes with my cherry ..... be kind :)

I've been using Gimp for a while so not totally green but certainly not strong in the "Editing Department" and have just switched to CS6

I always have a problem trying to replace skies where there's not a clear distinction between sky and ground and where there's a ground mist or sea mist but appreciate the software is also struggling as it's not that clear and wonder if anyone has any better / easier ways than I've tried so far.

Here is the one I've struggled with

G0012394.JPG

I've tried using colour range as well as the quick selection tool and the magic wand tool and the magnetic lasso. the quick selection tool would be the easiest but as I drag from left ti right it starts off fine and then all of a sudden as the sky darkens it suddenly gobbles up the sea with it and goes straight to the land. The Magic Wand takes ages as I start with one tolerance and then change accordingly to reduce the tolerance going from left to right, The Magnetic lasso I had a reasonable amount of success dividing between the land and sea but when I then try to do the straight vertical lines either side and the horizontal along the top despite being outside of the frame it creates a jagged line that keeps dropping down into the sky in places.

Any help would be appreciated but please be aware my understanding of some "jargon" goes waaaaaayyyyyy over my head, I can copy how people are doing it in you tube vids parrot fashion but I often have absolutely no comprehension what it means nor how one interacts with the other.... ie layers, masks etc

Actually if anyone knows of good spoon fed tutorials for those would appreciate as I really am struggling to get my head round them.
 
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Manually creating a marquee is always going to be much better than having some 'process' do it automatically. It takes a little longer, perhaps, but when you consider you'll get exactly what you want its a small price to pay....and it won't be that much longer anyway.

I'd say you're on the right track with the 'Quick Selection' tool, its just you're not using it correctly and are giving up way too soon thinking its never going to work.

This tool is unique in that it will 'learn' as you go the range of colours you wish to use for the marquee.
Used in conjunction with 'Alt' you can add to or subtract from the marquee....each time it will 'guess' more accurately than before until such time as it just goes back forth.

Try that tool again but use it with 'Alt' (The cursor will change to have a '-' sign in it), and add to and subtract from the very initial 'rough' guess it does on the first pass.....I got pretty good results of the sky in the supplied image using this technique.
(And that wasn't even the fullsize version neither.)

I'd still say you'd get better results with a more 'manual' method but I guess thats more a personal preference.

If you're still struggling after that we can soon whip up a short video for you to follow.

Regards.
MrToM.
 
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One trick I use is to add a curves adjustment layer and darken the image. This gives a more pronounced contrasted edge for the tool to work with.

To add a Curves Adjustment layer, click the half moon icon located at the bottom of the Layers Panel.

Screen Shot 2015-05-06 at 2.30.59 PM.png

Pull a gentle curve to darken the image slightly.

Screen Shot 2015-05-06 at 2.35.11 PM.png


Screen Shot 2015-05-06 at 12.58.57 PM.png

Highlight the Curves Adjustment layer....

Screen Shot 2015-05-06 at 2.31.52 PM.png

.......then use the Quick Selection tool as MrToM describes and you get a fairly decent selection.

Screen Shot 2015-05-06 at 12.59.10 PM.png

The you can turn off the Curves adjustment layer.

Screen Shot 2015-05-06 at 12.59.20 PM.png

Now that you have your selection (or marquee as MrToM calls it) highlight the original image layer.

Hold the Option/Alt key and hit the "add layer/vector mask" icon
located at the bottom of your Layers Panel. YOU SHOULD NEVER USE DELETE!

LayerMaskIcon.png

This will add a layer mask to your image.

Screen Shot 2015-05-06 at 2.32.47 PM.png

Your image should look like this.

Screen Shot 2015-05-06 at 2.44.03 PM.png

Then all you need to do is place the new sky image layer below the original image layer.
 
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Which layer did you have selected when using the QS tool Sam?

Or did you stamp it and go off that?

I'm not sure if 'selection' tools work off an adjustment layer or not.....do they?

That's a cool idea to 'darken' the image first for better contrast but which way do you need to do it?

Cheers.

Regards.
MrTom.
 
MrTom,
I didn't quite get what you meant, I tried using teh ALT key previously and tried it again and it didn't seem to make a difference, the only thing I'd say is it did possibly learn but i wonder if the wrong way as when I undid what I#d done and tried again instead of me being able to do some of it before it dropped down and swallowed all the sea loosing the island in the distance it did it instantly and went straight to the lower shore line ... I'm obviously not quite sure how I should be doing it.

IamSam,
I tried yours as well and although it confused me initially I managed to delete out the correct parts rather than bits I wanted on the 3rd attempt and got quite a reasonable result ....... whether I can remember how I did it and do it a second time around is another thing though :cheesygrin:
 
Scrub that....

Sorry....I'm confusing you...you are right its the 'Alt' key.
(That'll teach me to use two different apps at the same time!)

The thing to do is to just keep going with it.

As you make a marquee it will wander about yes, but just stop, hold 'Alt' and go over it until its nearer.....it may go too far but no worries....just let go the 'Alt' key and go over it again.

The more you do it the more PS will gather the colour range you want and will get better with each click and drag you do.

As Sam said, a higher contrast makes it easier for PS to distinguish 'edges' but it will get there using that technique or not.....but you must persevere with it.

Regards.
MrToM.
 
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Which layer did you have selected when using the QS tool Sam?

Or did you stamp it and go off that?

I'm not sure if 'selection' tools work off an adjustment layer or not.....do they?

That's a cool idea to 'darken' the image first for better contrast but which way do you need to do it?

Cheers.

Regards.
MrTom.
Excellent Question! Sorry I did forget to mention that yes, I selected the adjustment layer when I use the QS tool.

You had me second guessing myself so I did a few experiments and it works. Not sure were I read that trick, it's been awhile.
 
MrTom,
Have just been watching a tutorial as well and now understand exactly what you were trying to say!!!

A big thank you to both of you, wish I'd asked in here 2 days ago would have saved me HOURS of tearing my hair out :lol:
 
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Here's an example of creating a temporary version of the image having greatly increased local contrast and saturation to ease the burden placed on the automatic selection tools, and then using the mask developed with this image on the original image. In this case, I simply used ACR to make the temporary, throw-away version:

G0012394-tjm01-acr-ps02b_cropped_out_LHS-698px_hi-01_temp_version_enhanced_local_contrast_sat.jpg


This allowed me to make quite an accurate mask very, very quickly (ie, a few seconds) using nothing more than the quick selection tool. I then could play around with the sky completely separately from the non-sky areas, e.g.,

G0012394-tjm01-acr-ps03a_cropped_out_LHS-698px_hi-8bpc_for_GIF.gif

Now, once you have the sky under control, one can apply some final contrast and brightness tweaks to the overall image (if you like a more processed, wowie-zowie look).

G0012394-tjm01-acr-ps03a_cropped_out_LHS-698px_hi-8bpc_for_GIF-02_final_adjustments.jpg


HTH,

Tom M

PS - I cropped the LHS of your image because the clouds on that side were completely blown out and I couldn't recover any detail in them.
 
Tom,

Thanks for that and the links!!!

Thought I'd post what took me literally a few minutes to do and can get it to work easily now both ways either using the selection brush and "nudging it" to the right place which was what I didn't understand before as well as using the curve to darken it.
I'd be interested in any criticism people may have both of how I've replaced the sky but also any other comments re the general colouring and plese don't hold back and be blunt I really am still in teh infancy stage and open to any constructive criticism, I may cry like a baby but you won't see that :mrgreen: .........I wonder if I go a bit too "vibrant" sometimes so they don't look overly realistic and if I was going to spend time on it would remove the van on the road but really more interested to see what people think of the colouring

3rd DoneCropped.jpg
 
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The sky replacement looks fantastic! Great Job!

The image itself seems to be a bit over saturated and you've lost some much needed contrast. The greens are too bright. As you said yourself, it's a bit too vibrant.
 
OK ... here's my opinion ... and it's just an opinion.

On my hardware calibrated monitor, the image in Post #13 is overexposed by at least a half-stop, and probably more like 1 full stop. It looks like you tried to brighten up the photo, but did so indiscriminately (xcept for the sky). This caused other problems such as the day-glow greens that Sam mentioned, as well as severe localized problems such as the white front of the house in the lower LHC is now blown completely out and the red channel of the red car is now also just about blown out.

With respect to the replacement sky, I obviously am not from this area, and am certainly not familiar with the weather patterns there, but from a pure photographic POV, other than the blown highlights on the LHS of the original image, I greatly prefer the clouds from the original sky -- they have much more visual interest / eye appeal than the replacement version. I particularly don't like the white haze just above the horizon line towards the LHS of the replacement sky.

With respect to composition, unless this is supposed to be a documentary image that intentionally shows the large, nearby fields that are under cultivation (eg, to specifically appeal to farmers), from a pure photographic POV, the fields occupy way too much space in the image. I would crop much tighter on the LHS of the image.

I agree with what appears to be your general goal of brightening the image, but, before starting, I would verbalize to myself much more specific goals: I would want to make it look like it was taken on a nice warm, sunny day; adjust it so that the harsh shadows in the foreground are not so impenetrable, but slightly increase the contrast of the water and sky to make it look like there is less atmospheric haze.

To do this, one has to work on the different areas of the image separately. For example, the first thing I worked on is the house in the lower LHC. Next, I adjusted the color balance of the land areas to be considerably warmer, and specifically removed the blue in the shadow areas near the houses. Using the "Camera Raw" filter in PS, I separately increased the brightness of the shadow areas while leaving some pure black tones in some areas for contrast (ie, so it doesn't look overexposed). For the sky, I simply blended in some of the sky from my previous post with the original.

Descriptions in text can only go so far, and, in fact, can mean different things to different people, so to me, the best way to show what one means when one is critiquing a photo is visually, by example. So, attached is a comparison of your original (just cropped) with my most recent take on the image, this time concentrating on the final tweaks rather than the earlier issue of selecting the sky-water boundary.. Anyway, you asked for people's two cents / pence, so see what you think.

Cheers,

Tom M

PS - It occurred to me that there may be another reason why you brightened your image so much -- your monitor may be lying to you. Monitors can be that way, LOL. What I'm talking about is that unless you are using a monitor that has been independently calibrated to internationally accepted standards (ie, using a hardware calibrator), there is a very good chance that you are making changes that while they may look wonderful to you, on your monitor, on other monitors, they may look awful. So, consider this possibility, as well.

PPS - Because I had to use a GIF to do the before-after comparison, and the color palette of GIFs is limited to 256 different colors, it looks a bit ratty, but hopefully, you get the general idea of the direction I would go.


G0012394-tjm01-acr-ps04b_cropped_out_LHS-698px_hi-8bpc-brightness_tweaks_for_GIF2.gif
 

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