This video explains the f-stop scale used in photography and video. It explains what f-stop actually is and why the f-stop numbers are what they are. I also give an easy trick for remember the entire f-stop scale.

Dylan has some other videos explaining photographic concepts so be sure to visit his channel and see the others once you’ve watched this one.

Los Angeles street photographer Eric Kim’s 100 tips and observation about photography is a fun read for anyone who likes to get behind a lens, whether beginner or pro. Recently republished via the Times Photo Journal Facebook page, there’s a lot of sage advice here for just about any situation (example: “Alcohol and photography do not mix well.”).

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I have Lightroom 2, but have not really got my head around to understanding it – but then I don’t spend much time trying I suppose! The one thing that I find frustrating, is that images seem to “get lost”  – if I try to open some of my older images, it says “file missing or offline” – I don’t know how to get them back? Can you please help me if you can?

Lightroom is as much an image management system as it is an image processor. It uses a database to keep track of your images and the non-destructive changes it makes to them. There are several options for importing images, some of which reference an image where it is on your disk and others that copy it from a memory card to some place on your disk and then reference it from there. They key here is that Lightroom doesn’t have the actual image in its database, but a reference to it at some location on disk.

I will talk only in terms of Lightroom on Windows below but I believe the Lightroom functionality will be the same on the Mac and references to Windows Explorer can be substituted with Finder there.

Let’s say you have an image portrait01.jpg in a folder C:\Pictures\Portraits (no significance to the names, just chosen for demonstration) and import it to Lightroom. A record is made in the database, including the location of the file on disk (C:\Pictures\Portraits\portrait01.jpg). If you later move the image using Lightroom’s own management features, it knows where the image moved to and can update the reference to the disk location accordingly. If however, you were to use the image outside of Lightroom using Windows Explorer or some other tool, Lightroom will not know this. When next you use Lightroom it will look at the location it has, and not finding the file there will report the file missing or offline message. That covers the file missing aspect of the message. The offline aspect is a bit different. Let’s say your image is on an external USB drive that is mounted with a particular drive letter (G: for instance); Lightroom will record the location on the G: drive (say at G:\2011-06-17\photo04.jpg). Later when you run Lightroom without the drive connected, or if it is connected but mounted under a different drive letter, Lightroom will not be able to find the file  G:\2011-06-17\photo04.jpg and so the photo is missing. In either case you will still have access to many of Lightroom’s features; the database contains a low-res preview version of the missing images, along with all the metadata, keywords etc. so you will still be able to look for images, add keywords and so forth. No functions that require access to the actual photo file will work though.

The way to ‘get images back’ depends on whether the file is missing or offline. If it’s offline because the external drive containing it is not connected, just connect the drive making sure that it gets the same drive letter it had before, and Lightroom will now find the file. If you had moved the file outside of Lightroom you will need to use the locate function to point Lightroom to where the file is now. The image thumbnail will have an icon overlay showing the file is missing.

If you click on it you will be shown a message box asking it you want to locate the file.

When you click on the Locate button you are shown a standard file open dialog that you can use to select the new location of the file.

Unfortunately you need to know where the file is now, but Lightroom does give you a little help. On the confirm dialog the full path the the file, including the name is shown, so we see in the screenshot above that the missing file is called Colours of Light.jpg so if you don’t know where it is now you can at least use a search utility to help you find it.

Both Windows and Mac have built-in search utilities but I prefer to use a free third-party Windows utility called Everything for this. I can run Everything and type in all or part of the file name from the Confirm dialog to see where the file might be now.

We can see that I moved the file to the folder C:\Users\Steve\Pictures\Moved Files so I simply need to navigate there in the Locate dialog, select the file and Lightroom will once again have full access to the file. If you have not only moved but also renamed the file then you are not going to be able to do this if you don’t remember what the new name is and you may have to resort to deleting the image entry from the Lightroom database, but then you will lose any processing or keywording you’ve done on the file too.

It’s better never to have to do this; I know I don’t. But how is this possible? Simple. I never use anything but Lightroom to manage my photos. My advice is this; once you have imported your photos into Lightroom, don’t ever use Windows Explorer, Finder or anything else to manipulate your image files. If you need a copy of the photo at a different size, in a different folder or with a different name; export it from Lightroom so your original file remains untouched. It you want to move your files around, use the Library module in Lightroom to move them.

Unlike the old group the new one is not private but public, though membership is by invitation only. If you are sent an invitation to join and accept you will immediately become a member. If you haven’t received an invitation you can still join the group by visiting the group page at http://www.flickr.com/groups/hpsclub/ and clicking on the Join This Group. You will be presented with a page with a message form for requesting membership.

Simply send us a message asking to join, including your full real name as we may not recognise your chosen Flickr name. When we receive the request we will confirm that you are a club member and grant your request for admission.

Once you are a member you can start posting images to the group’s pool and taking part in discussions in the group’s forum. Although the group is public and non-members may view the images in the group pool, we have chosen to keep the discussion forum private so that only members can see it. You need therefore not be worried that outsiders will be able to read anything you post there. Image posting to the group pool is restricted to one image per day for each member, to ensure that a single member will not be able to post a large number of photos and flood the member’s photos gallery on the web site with their images.

If you don’t already have a Flickr account and would like to join the group simply go to http://www.flickr.com and click on the Sign Up button. You will be able to create a new Yahoo account (did you know that Flickr is owned by Yahoo?) from scratch or by linking with your existing Google or Facebook account. If you have an existing Yahoo account but not a Flickr one you should be able to log in (instead of signing up) with your Yahoo account and a Flickr account will be created for you. Once you have a Flickr account, go to our group and follow the instruction above to join.

We hope that this new group will be of benefit to you and that you will not only post your images but also use the discussion forum to get help with all those technical and creative questions for which there is never enough time to get answers at club meetings. In particular we hope that this group will give our country and international members a forum to interact with the club when they are not close by and able to attend meetings.

The solution to this is to add a narrow border in a contrasting colour to the image, which is enough to keep eyes from straying beyond the frame. This was mentioned in our latest newsletter with this link to a tutorial on one way to do it. That method involves increasing the canvas size and could lead to problems for those of our members already having problems in sizing their submissions for meetings. Here I provide an alternative way to to this that does not increase the image dimensions. The benefit of this is that you can export or save your club-ready image in the correct size then open it and apply this technique without affecting the image dimensions.

I am going to demonstrate using Adobe Photoshop, in this case Elements 7. The technique uses no advanced features and can be done with any version of Photoshop released in the past decade, as well as many other applications, though steps (and terminology) will differ.

Lets start off by looking at our sample image on a dark background.

We see that there is no definition at the edges of dark areas of the photo and light areas like the light streams appear to end suddenly in mid-space. In this case, and it varies from image to image, a narrow light-coloured border would be most suitable, so let’s see how to add one without affecting the image size.

Open the image in Photoshop and select the entire image using the Select | All menu or by pressing Ctrl-A (Cmd-A on Mac). You will see the marching ants indicating the entire image is selected.

We could shrink the selection, invert it so the outer edge is selected, then fill the selection with colour to create the border, but there is an easier way. Click the Edit | Stroke (Outline) Selection… menu to reveal the Stroke dialog.

If this is not the first time you are doing this the settings in the dialog may be correctly remembered from before, but we should check them anyway.

In the Stroke group, set the Width to 1 px (one pixel); use a larger value if you want a wider border. Click the Color swatch to open the Select stroke color: dialog and choose a mid-grey colour. The easiest way to do this is to grab the little circle and drag it down the left edge of the selector until the R, G and B values are all 127. Or you could just type 127 into each of the R, G and B fields.

Why don’t we use white for the border? A white border is in high contrast to the dark background and tends to distract from the image itself so it’s better to use a darker shade. It will be less distracting but still keep the eye from straying beyond the frame.

Click OK to dismiss the colour selector and return to the Stroke dialog. Location controls where the border will be drawn; Outside will draw outside the marching ants for the selected width and Center will draw along the marching ants drawing half the width inside of and half the width outside of the marching ants. What we want here is to select Inside so the full width we selected is drawn inside the marching ants.

Blending can be left at or reset to the defaults. Mode should be Normal, Opacity 100% and Preserve Transparency should not be available as your image has no transparency.

Having clicked OK to dismiss the Stroke dialog you won’t see that anything has happened as the border you just drew is hidden by the marching ants. Press Ctrl-D (Cmd-D on Mac) and you should see it. Depending on the size of the image and the magnification of the Photoshop view you may still not see it but id you zoom onto a corner or edge of the image you’ll see the border we created.

Now save the image and you’re done. When projected at the club on a dark background it will look like this and provide a better viewing experience.

Sometimes we may want to create a more complex border consisting of two or more lines in different colours. This can also easily be achieved with this technique, again without affecting the dimensions of the image. All we have to do is repeat the stroke operation for each different colour, starting with the innermost. Lets look at the case where we want to create a one pixel mid-grey border as we did before but also want a five pixel border inside that using a colour from the image. Repeat the steps we did before to the point you have the entire image selected.

We want to use the orange colour from the image for the inner border so we’ll use the eyedropper tool to pick it up from the image. Notice that the foreground colour swatch is now orange. Now click the Edit | Stroke (outline) selection… menu and notice that the selected foreground colour (orange) is automatically set in the dialog.

We want to draw a five pixel wide orange border but there is going to be a one pixel border around that so we must add 1 + 5 and make the width 6 px. Click OK to dismiss the dialog and we see the orange border, as it’s wider than the marching ants. Now, without deselecting, repeat the Edit | Stroke (Outline) selection… action, choosing Width as 1 px and Color as the mid-grey we used before. Now we have a border that looks like this, as it turns out not a very pleasing colour combination, but luckily this was just for demonstration.

What is High Dynamic Range Imaging? (HDR)

HDR is when you take 3-5 or 7 photos at different exposure settings, and then merge them into a single image using speciality software. What you get are beautiful photos with incredible detail, controlled lighting and accurate colour. You cannot reproduce an HDR image manipulating a single JPG or RAW image in Photoshop.

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Here’s a photo I took of a previous convergence, or conjunction as I believe the phenomenon is also known.

Dr. Tony Phillips writes on physorg.com,

The brightest planets in the solar system are lining up in the evening sky, and you can see the formation—some of it at least—tonight.

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Calibrating our monitors and printers is something that we, as photographers, should be particularly concerned with. Lifehacker recently made a blog post that talks about this, covering some of the options available.

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