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Floribunda
01-05-2016, 5:37pm
I usually post my photos at 800px when I resize them for the forum, hit tab, and it calculates it, and this is fine for landscape.
However when I crop to a vertical form they look too big to me.
What size woukd be a good starting point for a vertical post?

And - i would like to alter a colour in a photo - just the size of a single traffic light. I looked in "colours" but it changes the colour of the whole photo. I am thinking there must be a way to do it with a paintbrush.

Any help appreciated.

jev
01-05-2016, 5:57pm
Personally, I would prefer 600 pixels max height, but that is because I'm using a fairly old laptop that features a 1366 x 768 pixel display ;).

Anyway, as for changing colors locally: just use the lasso selection function to select anything you want changed, than change colours. Or use a second layer that has the colour change and add a mask to it. If you use a mask, you can draw and edit the mask the same way as any other part of the image so you can also use the fill tool for example.

ameerat42
01-05-2016, 7:14pm
Lyn. Are you expecting straight answers:D
1. Use Photoshop.:p
2. Use Photoshop.:p

Aw, OK (make me go and run GIMP)...

No, really. I don't know what "Tab" does, but it doesn't sound like much, so take control...
Pull up your image, do everything you want to it, then, when ready to RE-SIZE, do this...
1. Select Image, then Canvas Size
2. In the box, type in the side you want to make 1200 pixels.
3. Click on the little "Link" symbol just next to the size boxes and this will change the length of the other side.
(NOTE: This will be 800 if you're using a 3:2 ratio.)
4. Click "Resize".
For an illustration to here, see image below.

5. Save the image (:rolleyes:Save us from GIMP!) using the EXPORT, then select the jpeg format and give it
a quality setting (Default 99). If you find it's over 400KB, re-do the Export with a slightly lower value till you
get to just below 400KB.

Now, won't you get Photoshop? If you get the CS2 version it's :):D***FREE**:D:nod:

(And you're wondering why I don;t use GIMP:p)

Image Below...
125356

Floribunda
01-05-2016, 7:36pm
Personally, I would prefer 600 pixels max height, but that is because I'm using a fairly old laptop that features a 1366 x 768 pixel display ;).

Anyway, as for changing colors locally: just use the lasso selection function to select anything you want changed, than change colours. Or use a second layer that has the colour change and add a mask to it. If you use a mask, you can draw and edit the mask the same way as any other part of the image so you can also use the fill tool for example.

Ta - Will have a try at that. It has to be simple - I HATE pp. necessary evil. :)

- - - Updated - - -

Thanks Am. I had Photoshop - too complicated and Gimp has the resynthesiser plugin that I use ALL the time. I do very little pp - I find it a chore -
Will fiddle with what you have suggested. Ta.
Expect more questions. :D

Mark L
01-05-2016, 8:13pm
I usually post my photos at 800px when I resize them for the forum, hit tab, and it calculates it, and this is fine for landscape.


Not big enough. 1000 for landscape.
You have to change the height (not the width) size for portrait photos. 780 to 800 works (if you apply it to the height).

jev
02-05-2016, 11:06pm
a quality setting (Default 99). If you find it's over 400KB, re-do the Export with a slightly lower value till you
get to just below 400KB.
In the export-dialog is an option named "Show preview in image window". If you tick that, it'll show the compressed size and change it accordingly when modifying the compression ratio.
http://i.imgur.com/kk5d6II.png

Floribunda
03-05-2016, 9:30am
In the export-dialog is an option named "Show preview in image window". If you tick that, it'll show the compressed size and change it accordingly when modifying the compression ratio.
http://i.imgur.com/kk5d6II.png

Thanks Jev - will look at that.

- - - Updated - - -


Personally, I would prefer 600 pixels max height, but that is because I'm using a fairly old laptop that features a 1366 x 768 pixel display ;).

Anyway, as for changing colors locally: just use the lasso selection function to select anything you want changed, than change colours. Or use a second layer that has the colour change and add a mask to it. If you use a mask, you can draw and edit the mask the same way as any other part of the image so you can also use the fill tool for example.

I haven't had time to fiddle with this Jev, but will. I haven't come to terms with layers and masks yet so KISS is the way for me. I want to get rid of the green in a traffic light and change it to Amber leaving the rest of the photo alone.

ameerat42
03-05-2016, 9:39am
Lyn. It's OK. Ask away and it'll help keep me on my GIMP toes. I have the prog but hardly use it:D

- - - Updated - - -

Ta too to Jev for the info.

Floribunda
03-05-2016, 9:51am
Lyn. It's OK. Ask away and it'll help keep me on my GIMP toes. I have the prog but hardly use it:D

- - - Updated - - -

Ta too to Jev for the info.

It is nice to have found some Gimp friends here! :nod::)
Since using Gimp I have found it much more user-friendly for simple folks like me than Photoshop. It is lazy I know to pose questions instead of researching oneself, but there is so much info out there I tend to get confused these days. Thanks for help so far - as I said, there will probably be more questions! :D

jev
03-05-2016, 4:33pm
I'll try to make you a nice little tutorial for this later today. Stay tuned (but don't hold your breath) ;).

Floribunda
03-05-2016, 5:16pm
I'll try to make you a nice little tutorial for this later today. Stay tuned (but don't hold your breath) ;).

That would be SO good jev.

jev
03-05-2016, 9:12pm
Okay, here it is. I just took a photo from the 'net from a couple of trafficlights and decided the red light should be blue:

https://www.youtube.com/watch?v=gW4-VaiH5Xs
The steps:

Open the layer dialog if it's not already open (click "Windows > Dockable dialogs > Layers" or just enter Ctrl-L)
Activate the layer by clicking on it in the layer dialog
Duplicate the layer (click "Layer > Duplicate Layer")
Select the new layer by clicking on it in the layer dialog
Click "Colors > Hue-Saturation...", than click the radio button for red in the color selector
Adjust the selected color by dragging the Hue slider
Close the dialog by clicking the OK button
Add a layer mask (click Layer > Mask > Add Layer Mask", choose "Black (full transparency)" and click OK
In the layer dialog, you'll notice the mask is shown besides the top layer. There should be a white marker around it, indicating it is selected. If not, click on it.
Now take a white brush and, paint the parts you want to get the changed color.
When you're done, merge the layer down ("Layer > Merge Down")
Finish!


It reads like a long series of steps but it really isn't, see the video.

Hope this helps, don't hesitate to ask if there's anything unclear!

Floribunda
03-05-2016, 11:24pm
Okay, here it is. I just took a photo from the 'net from a couple of trafficlights and decided the red light should be blue:
https://www.youtube.com/watch?v=gW4-VaiH5Xs
The steps:

Open the layer dialog if it's not already open (click "Windows > Dockable dialogs > Layers" or just enter Ctrl-L)
Activate the layer by clicking on it in the layer dialog
Duplicate the layer (click "Layer > Duplicate Layer")
Select the new layer by clicking on it in the layer dialog
Click "Colors > Hue-Saturation...", than click the radio button for red in the color selector
Adjust the selected color by dragging the Hue slider
Close the dialog by clicking the OK button
Add a layer mask (click Layer > Mask > Add Layer Mask", choose "Black (full transparency)" and click OK
In the layer dialog, you'll notice the mask is shown besides the top layer. There should be a white marker around it, indicating it is selected. If not, click on it.
Now take a white brush and, paint the parts you want to get the changed color.
When you're done, merge the layer down ("Layer > Merge Down")
Finish!


It reads like a long series of steps but it really isn't, see the video.

Hope this helps, don't hesitate to ask if there's anything unclear!

It is really good of you to go to this bother jev.
As soon as I get a quiet moment I will give it a go and let you know how I get on.
Thanks a lot.