My first picture to be shown!

[Daniel Salazar]

Hi, this is the first time that I'm posting a picture, could you please help me giving me your opinion. I know that the composition is not good and I don't know what else.

http://homepage.mac.com/daniel.salazar/Posting/

Cheers,

Daniel

[The Blue Boy]

I like the pictures Daniel. My only critique (and it's not critique as such) would be that the composition leads my eye to the right of the picture and along the bridge and then it stops. I may have taken a few more shots to create a panoramic image, thus showing a bit more of the place. Just don't tell me that over the bridge is the world's ugliest power station!

[David]

Hi Daniel - Thanks for posting this interesting picture. I think that as a documentary image showing town, river and weir there is nothing too bad about the composition, but there are some particular points that might enhance the shot. First, there are branches hanging in on the right-hand side. These could be cropped and/or cloned out together with some of the bottom river water to give a tighter shot. Second, the colours are rather muted so enhancement of saturation and brightness can be done to bring out the sky. Third, perspective correction to make the towers vertical would be important. Fourth, some extra sharpening always helps. Finally, when cropping you can resize the image to give a slightly elongated format. I learnt this tip from Colin Southern and it can be very useful if you have a horizontal or near horizontal axis in the image.

Here's my go (I hope you don't mind):

http://farm4.static.flickr.com/3453/...40a18eb0_o.jpg

(As often is the case, I can't get this image to post here, but the link works.)

I used Paint Shop Pro 9, cropping and cloning in the usual manner, brightening via a second layer blended via screen mode and erasing anything to do with the clouds and sky. Finally, I used a mild high pass filter to sharpen.

Cheers

David

[peter2108]

Thank you for the adjustments - I'd never have seen them! Thank you too dasle for posting the picture. I have two questions. First how can a software acheive perspective correction? Second - what is a mild high pass filter? I have Lightroom 2 and Gimp but not Paint Shop Pro.

Cheers,

Peter

[Dave Humphries]

Hi Daniel,

I would in general echo David's comments; I'd say there's nothing drastically wrong with it, I would do the perspective and increase the saturation (maybe not quite as far as David has) - on this point I did notice from the EXIF you have the camera in AdobeRGB colourspace, which would account for the lack of colour in what I'm seeing viewing it in sRGB - there's much on this in other threads and I'm certainly no expert, so I'll leave that topic at this point.

I do find David's version a more "interesting" picture, being that bit closer cropped, I can see more of the architectural detail on the far bank. It also seems to deal with Mark's point to a degree.

It might stand still more sharpening, even more than David's version, if carefully done.

Also, although it has been very sensitively done, the 'horizontal stretch' idea obviously has drawbacks with any subject containing say, clockfaces or other circles. It may be better applied to 'natural' subjects than manmade.

I'd say you're off to a good start with this shot Daniel; keep posting.

Hope that's helpful,
Dave

[Colin Southern]

Hi Daniel,

Hope you don't mind, but I made a few adjustments too - what do you think? (can tell you more about it if you like the result).

Cheers,

Colin - pbase.com/cjsouthern

[Zephyrize]

Nice shot Daniel, I especially love seeing those kind of european architectural shots! Reminds of me my trips to Europe.
I agree that I would have taken another shot a little bit to the right to show a bit more of the bridge and let the tree branches take a little more space on the top right corner.

a little bit of colour grading could make this shot more dynamic like what Colin did, it has now a great warm atmosphere. My only critic Colin is maybe the reds are a bit too saturated; the balcony on the left tower seems more like orange-brownish in the original shot, oppositely to the last one on the right.

other than that, hope to see more architectures from you !

[Colin Southern]

"My only critic Colin is maybe the reds are a bit too saturated; the balcony on the left tower seems more like orange-brownish in the original shot, oppositely to the last one on the right."

It was actually a bit tricky to process - the image has a good range of tones, but the brighter ones were mostly in the sky, leaving the buildings looking a bit flat and under-exposed (I could have masked off the sky, but was feeling lazy Really needed a GND filter.

In the end I processed it in LAB colour and steepened the slope on the A & B curves by different amounts. When you do it that way it drives colours apart and increases saturation, but it also becomes very sensitive to colour casts (which it had to begin with - so I had to try and null it out) (I left it with a warm tone). In the end I pushed the colours as much as I could - to the point of oversaturating the reds, then desaturated the red bits with the sponge tool. I also dodged the highlights on the falling water - and did a little burning on the clouds to try and coax a bit more definition.

Gave it a small top/bottom crop, and stretched the remainder to my "trademark" 2:1 aspect ratio.

[Daniel Salazar]

Wow! I didn't expected so much help guys, this confirm why I decided to join this forum. Thank you again!

I really don't know where to start, there are so many tips.

Firstly, I really didn't even consider doing a pano picture, which might be an interesting thing to do. Just to say something in my favor, I do remember that on the right side of the river there is a parking lot, it is not ugly power plant but is also not so interesting.

Secondly, I'm always really cautious about color adjustment, therefore I tend to use not so saturated colors, from now on I won't be so insecure, however I thing that I should try not to exaggerate.

Thirdly, perspective correction. I have to remember that, however one question, if you can appreciate, the tower on the left side has a different vertical as the church tower and the tower on the right hand. Then I don't know what is more important to check, the one closest to the front or the one in the back?

Also, as Dave pointed, it seems that taking the pictures using AdobeRGB colour space could create a problem. I though that when having a color managed environment the computer should adapt the colour space using with the camera to the one use to print or to the one the screen needs.

By the way, welcome to the forum Peter. I've Aperture, so I don't know how you can correct perspective with Lightroom and I don't have any idea what is a mild high filter ad I use the filters from Nik Software.

Now I've made some changes according to all your recommendations. Thank all you you!

http://homepage.mac.com/daniel.salazar/Posting/

Cheers

Daniel

[Dave Humphries]

Hi Daniel,

No worries, we're here to help.

Thirdly, perspective correction. I have to remember that, however one question, if you can appreciate, the tower on the left side has a different vertical as the church tower and the tower on the right hand. Then I don't know what is more important to check, the one closest to the front or the one in the back?

Many image editing programs have a function that might be called 'Transform (free)' or 'Perspective' that would allow you to get both sides right.

Imagine your picture printed on an elastic (stretchy) material, to view it, you might put a pin in each corner to hold square.
Now imagine unpinning the top left corner and stretching that further left and up, until the tower on left is now vertical and sticking the pin in again.
Now imagine unpinning the top right corner and stretching that further right and up, until the church on right is now vertical and sticking the pin in again.
Now if you overlay a rectangular (picture) frame, the tower and church are now both parallel to the sides.
That's what you can do electronically, but exactly how depends on your editing package - and my only experience is Photoshop Elements 6.

Hope that helps,

[peter2108]

Ah - the GIMP has a 'perspective' transform which operates like a rubber bnad grid as you say. So that's that clear. But how do you process something in "LAB colour" and what are A & B curves? And finally what program lets you do this?

-- Peter

[David]

Hi Peter 2108 - You ask about perspective correction and high pass filtering. I think RustyShutter has dealt with the perspective correction idea, although I would add that different software packages often have different controls for carrying out the same idea. It is a matter of trying things for yourself until you get the hang of it.

High Pass filtering is a method of sharpening. There are built in functions in the Gimp and in Photoshop for doing this but you have to create your own for Paint Shop Pro. The advantage over unsharp mask sharpening is that High Pass filters are not so aggressive and tend to concentrate sharpening on well defined edges rather than the whole image. In essence, the method is very simple. Create a duplicate layer and use a user-defined function to change that layer to a greyscale that has only the edges of the image showing. Then blend this with the original layer using Overlay mode, usually with about 50% opacity.
The user-defined function in PSP is found under effects>user defined filter. Fill in the value 12 in the central box and the value -1 in each of the 12 diagonal boxes. Set Divisor to 4, bias to 128, and check greyscale. Apply. You can create a script to carry this out, which is what I have done. The particular parameters that I have described gives a good general purpose High Pass filter, but you can create others.

Have a go and get back to me if you need further info. BTW, Daniel's photo was not a large file, and so any sharpening can easily be over the top.

Cheers

David

[dendrophile]

But how do you process something in "LAB colour" and what are A & B curves? And finally what program lets you do this?

-- Peter

Hey Peter,

LAB is a colour space, so is a peer of the well known RGB and CMYK colour spaces. LAB is a bit special really. L, A and B refer to colour channels (just like R is red, G is green and B is blue.) L represents lightness, with zero being black and 100 being diffuse white. Then A shows how much magenta-green, with negative values being magenta and positive being green. Finally, B is the amount of yellow-blue, again, with negative values of B meaning blue, and positive values meaning yellow. Wikipedia can give a much more technical description of LAB.

Curves are a way of adjusting the colour balance in an image or channel. Curves show how input values of colour become output values. They are basically graphs. Colin is referring to curves that are changing the A and B channel colour balance, colloquially called A and B curves.

I guess many photo editing applications will let you edit in LAB colour space. Certainly versions of Photoshop from at least CS have had LAB support.

Search for "canyon conundrum" for the definitive book on using LAB colour space in Photoshop.

HTH,

Graham

[Colin Southern]

"But how do you process something in "LAB colour" and what are A & B curves? And finally what program lets you do this? "

What Graham said! (well done Graham - I was looking for something to add to what you wrote - couldn't think of a thing!)

Peter,

Along with Canon -v- Nikon, Mac -v- PC type debates, there is another - it's LAB -v- RGB processing. It's an interesting one because (grossly over simplified), "RGB" works in a similar way to how our eyes capture a scene, but LAB works more the way our brains process that information. Some will argue that anything you can do in LAB you can also do in RGB whereas in my experience although this is probably true, I think that often you can make certain sorts of corrections far more easily in LAB. LAB gives you the chance to seperate colour from luminosity - and perform seperate operations on them.

Personally (and I do stress that it is just a personal thing), now that I've got used to working in LAB colour I prefer it to working in RGB - for many reasons. As Graham suggested, The Canyon Conundrum is THE reference text on LAB processing - and Scott Kelby himself stated in no less words than "This will change the face of colour correction forever". Darn good book if you're interested, although very heavy going in places (but no pain, no gain).

Cheers,

Colin

[Daniel Salazar]

It was actually a bit tricky to process - the image has a good range of tones, but the brighter ones were mostly in the sky, leaving the buildings looking a bit flat and under-exposed (I could have masked off the sky, but was feeling lazy Really needed a GND filter.

Hi Colin, I've a question. When I was taking the picture I pointed to the blue sky to get the "correct exposure" and then I recomposed (I took the picture in Manual Mode). Does it means that it's better to meter the houses instead of the sky? I did it like that, because I wanted to avoid having a really bright sky, because it's possible to recover underexposed details instead of overexposed.

That is for me the most difficult part, where exactly to meter. e.g. then taking a picture on a beach or where there is a lot of snow, is it better to meter the sky?

Cheers,

Daniel

[Colin Southern]

Hi Daniel,

The problem is that with a scene like that it's quite possible that your camera won't have enough dynamic range - so if you're going to capture the image with a single shot (without graduated filters) then it's quite possible that you'll end up in a "no win" situation; if you expose the sky correctly, you end up with with the buildings being quite dark, and yet if you expose for the buildings then you end up with blown highlights. In some cases you just have to decide which is more important, so from that point of view there's no "wright or wrong", and the way you did it is quite acceptable. At the end of the day, the reason the buildings are dark is because (compared to the sky), they ARE dark. However ...

... if you wanted to do a "better" job then you could:

1. Shoot the scene at a time when the sky wasn't so brightly lit in comparison to the buildings, or

2. You could take 2 shots - one exposed for the sky, the other exposed for the buildings - and combine them in photoshop to reveal only the best parts of both images (called masking), or

3. You could use a graduated neutral density filter to give more attenuation of the sky (probably about 2 stops needed), or

4. You could take 2 shots and combine them as an HDR image.

If you shoot RAW then you can generally dig out a few extra stops of dynamic range, but it's hard to get contrasty, but natural looking clouds - but still retain good building levels - without masking off parts of the image and even then it's often hard to get "great looking clouds" (in my opinion clouds are easiest to deal with when you shoot them seperately, about a couple of stops under-exposed (in RAW) and process them from there (when you push them to the limit I suspect that people often lose detail when one or two channels blow, but not all three - and generally cameras won't warn you of this - under-exposing them generally seems to reveal more colour).

Hope this isn't "information overload" - happy to expand on any of the above if it helps!

Cheers,

Colin - pbase.com/cjsouthern

[peter2108]

Wow - I've learned a lot here and now I see there's 10 times more to learn. The high pass filter for sharpening. In GIMP there is a 'generic' filter where you define your own by filling in a matrix. But the fields are not the PSP ones so you need to understand a bit more. I found http://www.gimp.org/tutorials/Sketch_Effect/ which creates a high pass filter by subtraction from a low pass blurring one. Well, I am on my way. As for LAB you can decompose a picture
into LAB layers ... so I have a way in to this but have not had time to go further. Today I have to do Django websites so will have to put that on hold.

Thanks again for all the help. Be seeing you ...

-- Peter

[dendrophile]

Peter,

Take a look here. It's a small tutorial I put together (for members of a camera club I used to belong to) that describes the first tiny steps of editting in LAB space. This is really describing the first things that Dan Margulis recommends in his book, so I don't take any credit. There are some screenshots interspersed with photos, so should be easy to follow along, even if you don't "do" photoshop.

Enjoy,
Graham

[Daniel Salazar]

Hi Daniel,

... if you wanted to do a "better" job then you could:

1. Shoot the scene at a time when the sky wasn't so brightly lit in comparison to the buildings, or

2. You could take 2 shots - one exposed for the sky, the other exposed for the buildings - and combine them in photoshop to reveal only the best parts of both images (called masking), or

3. You could use a graduated neutral density filter to give more attenuation of the sky (probably about 2 stops needed), or

4. You could take 2 shots and combine them as an HDR image.

Hi Colin, thank you for the advice. I was already considering to buy a 3 stops graduated density filter, would it be better than a 2 stops or is it not worthed?

I'll try always then shooting always one picture metering the sky and another one metering the subject, then combining them as an HDR image, however the downside is that I might always need to carry my tripod, or to PP using PSE 6.0 or even better, use the option included in my camera to take pictures with diferent exposure values

Cheers,

Daniel

[peter2108]

Graham - I have got it and will have a go!

Thanks, Peter