The Curves Tool

The curves tool is a very basic tool that can be used to improve photos with a few clicks of the mouse. It is used to change the brightness and contrast of an image. It can also modify the separate Red, Green and Blue channels of an image too. The Curves Tool has a histogram to represent the shadow, midtone and highlight detail in the image. In the GIMP, you access it by right clicking on an image and go to Colors->Curves.

This is the second article in my GIMP for Photographers series, but as usual, all of this applies to Photoshop, or any other image application with a Curves Tool. The first tutorial was on The Levels Tool, and worth a read if you missed it!

Here’s an image I shot at the Lord Mayor’s Picnic in Fitzgerald’s Park a few months ago, and the Curve Tool below it. Notice the histogram? The photo is fairly well exposed, but some highlights are “clipped”, as the histogram hits right hand side without sloping off.


Brightening Curve

It’s easy to brighten an image. Just drag points on the line up.


Darkening Curve

Now, let’s darken the image by dragging points down.


Contrast Curve

A classic use of the Curves Tool is to increase contrast in an image. You do this by darkening the shadows, and brightening the highlights. The curve looks sort of like an “S” when you do this. Don’t go overboard on this though, because it’s easy to lose detail in either direction.


If for some reason your image has too much contrast, a quick inverted S curve will solve that problem,


Wacky Colours

You can select any of the Red, Green and Blue channels and do strange things to your photos. Here’s what happens when you play with the Red Channel.


And here’s what happens when you change multiple colour channels in different ways.

Colour Picker

After you have opened the Curves Tool, click anywhere in the image. Notice how a vertical line goes up and down the histogram/line? That vertical line is the colour of the pixel where you clicked. That can be useful if you’re trying to modify a particular part of a photo. This is what you get when you click on the black coat on the left of the image above.

Aperture ƒ/6.3
Camera Canon EOS 20D
Focal length 18mm
ISO 200
Shutter speed 1/250s

What! The Canon EOS 50D announced already?

Yes, yes, boo hoo, oh woe is me, my Canon 40D arrived on the day the new Canon 50D was announced. If only I had waited, my photos would be so much better with the Canon 50D.

Yeah right. I’ve already stated before that the equipment behind the camera is the most important part of image making. Sure, the camera does matter, but DSLRs are getting to the stage PCs got to a few years ago. Upgrading doesn’t significantly change the game. I’ll upgrade again in maybe 3 years. No rush.

The Canon 50D looks sweet though. 15MP sensor, better ISO, better LCD. Nice upgrade. Roland has linked to a few of the sites previewing or discussing the Canon 50D. The Rob Galbraith page is probably the most readable, but the DPReview preview has a neat comparison table to compare the Canon 50D with the Canon 40D.

DIGIC 4 processor Canon’s next-generation, 14-bit DIGIC 4 processor see its debut in the 50D, and it offers both more functionality and about 30% faster processing speed than the DIGIC III processor in the 40D….

The two cameras’ dimensions, body style and control positions are also the same (though the 50D is fractionally lighter). In a nutshell, the 50D appears to be a 40D with a higher-resolution sensor, revamped image processing, faster CompactFlash write speeds, HDMI video out and a crisp new rear LCD.


Love this pic of the motherboard with the DIGIC 4 processor!

GIMP FX Foundary is a massive GIMP plugin archive

I’m surprised I haven’t blogged about The GIMP FX Foundary before. It’s a huge collection of GIMP plugins that have been updated to work with the latest GIMP.

All the plugins were already available in the GIMP Plugin registry or elsewhere but not all of them survived the changes to Scheme in the latest versions of GIMP. I downloaded these plugins ages ago and recently grabbed the updated tarball with over 100 plugins. You’ll see the results of those plugins over the next few weeks as I play around with settings and effects.

I could go on and on about it, but why bother? It’s a small download and free so why not grab the zip file yourself?

Spencer Tunick photoshoot in Blarney Co. Cork, Ireland

As luck would have it, one of the more famous or perhaps notorious photographers of our time, Spencer Tunick, is shooting in Blarney, where I live, tomorrow morning.

Update on Jun 8th, 2009 – I’ve justed posted a small gallery of Spencer Tunick photos as his website is down.

It’s no great secret now, even Ray D’Arcy revealed the location on his radio programme this morning. He’ll be revealing a lot more in a few hours time.. Anyway, it all happens very early in the morning, at a time when most sensible people will be snuggled up in bed and that probably includes me. If I do feel the urge to visit Blarney Castle at dawn I’m sure all I’ll photograph will be groups of dazed and tired volunteers stumbling from buses, full clothed. I have no desire to shoot any naked skin.

Spencer – if you’re reading this, I’d love to go to shoot a portrait of yourself, and perhaps grab an autograph!

There are lots of people looking for Spencer Tunick’s Blarney photoshoot!

The state of street photography in the UK

Scary. I blogged previously about photographer’s rights in Irelnd but it appears that UK Police are ignorant of those rights which are similar to Ireland’s. I have never been stopped by Gardai (the Irish Police Force) taking photos on the street, but in the UK it seems to be a growing problem for photographers. Have you ever been stopped shooting photographs in a public place?

Make sure to read Photographer’s Rights from DIgital Rights Ireland to find out more about your rights as a street photographer in Ireland. If you travel you should always be aware of local laws as they’re liable to change in every jurisdiction. (via dslrblog.com)

Irish Photographers dot org

Irish Photographers are a busy lot. There are a good few photobloggers in this country publishing photos either daily or almost daily and they’re producing some amazing stuff! Unfortunately it’s sometimes hard to find them because photoblogs don’t always lend themselves well to search engine analysis. That’s where Irish Photographers.org comes in.

Irish Photographers.org will aggregate the content from some of Ireland’s best photoblogs (the others haven’t signed up yet!) and make it easy to discover new talent. I’m quite excited by this project and the enthusiastic reaction from other photobloggers has been great!

So far there are 10 blogs contributing to the site, but that number was limited to my contacts on Twitter and by my own limited spare time to work on this. If you’d like to have your site added, go to the About page, read through the short list of guidelines and fill in the form.

The site isn’t perfect by any means, the theme could do with a bit of tweaking. It needs a favicon and a web 2.0 button would be great. Anyone want to volunteer?

PS. Don’t forget the Doneraile photowalk on June 8th! There will also be a photowalk in Dublin this weekend. If you’re not a member of Facebook, here are the details:

A photomeet at the Dublin Maritime Festival. We can meet at the Harbour Master (link below) at 1pm.
Event: June photomeet. “photomeet greatfunaltogether”
What: Festival
When: Sunday, June 1 at 1:00pm
Where: Dublin Docklands

Redmum is organising this photowalk. Just in case you’re wondering why her blog isn’t included on Irish Photographers.org, it’s for technical reasons; blogger doesn’t offer per-category feeds unfortunately. She’s working on a solution so hopefully she’ll be contributing soon!
PPS. Cork City Marathon is on June 2nd. I hope to be there. Leave a comment if you think you will too!

How to short circuit

Ever since I posted Short Circuit I’ve been meaning to post a small tutorial on how I did it. There were so many comments from people clamouring to know the secret of how I made traces of light dance around the picture frame.

Actually, nobody asked. Will was kind enough to suggest another title but otherwise it went unremarked. *sob* I’m going to tell you anyway.

The image is a long exposure shot, of at least 1 second and preferably 4 or 5 seconds. I simply stood in front of a construction site at night, lifted the camera, hit the shutter and rotated the camera around in my hands. Needless to say, I did not have the strap around my neck or I would have done myself damage!
At first I tried Aperture Priority mode, setting the aperture really small (big numbers, around F/22), but then I decided to do the obvious, and used Shutter Priority and simply set the speed(time) I wanted. Below are a few shots from that night, including the scene as it was on the night and some experimental shots as I practiced. The technique is really easy, but can create some really interesting and eye catching photos.


Aperture ƒ/3.5
Camera Canon EOS 20D
Focal length 10mm
ISO 800
Shutter speed 1/10s

Doneraile Photowalk on June 8th

The month of June is going to be a busy and exciting one as the Midsummer Festival will be in full swing! To avoid clashes with any other event I think it’s better if the photowalk in Doneraile, Co. Cork be on Sunday June 8th before it starts at all.

Where: Doneraile Park, Co. Cork.
When: Sunday, 8th June. 3pm
Directions: Leave Cork going north through Blackpool towards Blarney and Mallow. Pass through Mallow and keep on the main road until you get to “New Twopothouse”. Doneraile town is sign posted there so take a right. When you get to the town go through it to the other side. You’ll see Doneraile Park sign posted. See the Google Map above, or check this one for the route.

Doneraile Park is a beautiful park with at least one river running through it, a small weir near the carpark. Deer and livestock can often be seen in some areas of the park as can fowl like ducks or swans. Doneraile House overlooks a large part of the park and is famous because a member of that household was the only female Freemason. The house was closed the last time I was there and I’m not sure if it’s ever open to the public. It faces north from what I can remember so you’d have to be there before noon to catch any sun on the front of the house.

If you’re going to blog about this, or post photos afterwards, please tag them “corkphotowalk” so anyone interested can find them easily!

More:

Cork Midsummer Festival

If you can’t make it to Doneraile on the 8th, there’s still plenty happening in the weeks after as the festival starts on the 15th and continues for 3 weeks. I’m particularly interested in the following, mainly because they’re outdoors, and as they are in public places, photography won’t be a problem.

  • Sunday, June 15th from noon to 6pm. The Lord Mayor’s picnic in the park. Fun and games and food stalls in Fitzgerald’s Park, Cork. I was there a few years ago. Lots to see, plenty to photograph, although we’ll have to be considerate of children.
  • Saturday, June 21st. Shandon Street Festival. Music and entertainment on the street all day. At 1pm in front of Brown Thomas there will be a Bicycle Ballet. It lasts 30 minutes. Must try catch both.
  • Saturday and Sunday, June 28th to 29th. Senszione. Sounds like a weird fairground with unusual looking rides. Unfortunately it’s at 6.30pm, 7.45pm and 9pm. Both earlier times are bad for me, but I’ll try for 9pm. Bad light then of course but it can’t be helped.
  • Saturday, July 5th. Robodock. IAWS Warehouse, Cork Docklands at 3pm and 8pm. I’ll be going to the 3pm show. Remember those weird iron sculptures in Emmett Place on St. Patrick’s Day? Lots more of them. The Docklands is due to be developed so it’s worth getting down there if for no other reason than to record something that won’t be able to happen there again.

I almost forgot. The Cork City Marathon is on Monday, June 2nd. Grab your place at the finish line!

Phew. It’s going to be a busy month!

Still waiting after all this time

On November 15th 2007 I took my Sigma 10-20 wide angle lens into O’Learys Camera World in Cork to be repaired. (I found out they were using some of my photos without permission too, but that’s another story. Read the linked post above!)
Several phone calls followed over the weeks after that. Eventually I was told that parts had to be shipped from Japan.

Roll on 5 months later to April 15th 2008. I rang O’Learys Camera World and got on to Andrea. She had to check my docket number and was gone for quite a while, during which time several members of staff tried to make phone calls. Beep, beep, beep and I’d wait for them to put the phone to their ear before saying, “I’m waiting on someone to check a docket for me”. After what seemed like an age, Andrea finally came on the phone again. She couldn’t get in touch with anyone and rattled off the same old story about shipping parts from Japan. She’s said she’d ring me back in 5 minutes after speaking to the repair shop in Bandon.

Oh, and that took almost 11 minutes to find out. Grrr.

A few minutes later she rang back. The repair guy is off today, she’ll be off tomorrow, but she’d leave a note for Declan to ring them again. Hopefully he rings me, and I have to wonder at the inventory system of a repair shop that doesn’t have a database a secretary can check ..

If I didn’t have Matt‘s old lens I’d be really pissed, but as it is I’ve been without an expensive piece of equipment for too long.

O’Learys Camera World – you screwed me over by using my photos to sell your digital photo frames without asking my permission. Now you’ve kept my lens for 5 months. Please don’t expect any business from me in the future once this debacle is sorted out.

Hopefully a few members of Mallow Camera Club will read this and pass the word along. I gave a talk at the club last night on educational websites. Here’s a list of the sites I covered. If you’re new to blogs, it’s a good starting point for any budding photographer.