Tag Archives: technique

Sound for the Videos

While I have experimented with video a fair bit over time, one thing I haven’t done is put together a video with a presenter in it. My mum was recently staying and she had an idea for something she wanted to do that involved her doing a presentation on video that could be shared at a later date. My own experience and some information I had seen online made me think that the key to getting a good result was not going to be the video but was instead the sound. The microphone on the camera is of okay quality but it picks up the sound of everything around it. The voice is isolated and any video online that does not take a careful approach to audio is very obvious and sounds decidedly amateurish.

The ideal solution would be to have lav mikes, the small mike you see attached to the clothing of TV presenters. These are actually pretty accessible and cheap but I didn’t have the time to sort something out. However, a surprisingly good alternative was readily to hand. I have an app on my phone for sound recording which I use when interviewing people for articles. Instead of using the plugin microphone, I used the headphone/microphone cable. By running it inside the clothing and just leaving the microphone up near my mum’s throat, we were able to make a very good sound recording. The closeness of the mike to her mouth meant the sound was very localized and clear so the background noise was lost. The room we used did not have bad echoes either so the audio ended up being pretty clear.

Then it was just a case of having a conspicuous clap on the audio track and the video file to allow me to synch the sound and audio together and we were off to the races. I shot everything with two cameras – one head on and one from the side – with the idea of cutting between them. However, when I did the first edit, the side camera didn’t seem to fit with the style of presenting to camera. I imagine it works better for an interview style piece. I reverted to the head on shot with some images cut in periodically to illustrate the piece. Overall, it worked pretty well. We did a number of takes and mum got progressively more relaxed in each one. I had thought I might cut the best bits together but the final take was really good so I didn’t need to do so. I hope her audience likes the result.

Trying to Remove the Traffic on the Bridge

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The suspension bridge at Lions Gate in Stanley Park, Vancouver is a magnet for photographers. I was only passing through but, as we watched the traffic moving across the bridge, I was thinking about how to get a shot that didn’t have cars on it. The traffic was steady so there was not way I would get a clear moment. Indeed, while we were there, they changed the lights and reversed the center lane based on the traffic demand.

I didn’t have a tripod but I did decide to experiment with an alternative technique. This is best done using a tripod and a lot of exposures but I figured I would go with shots that were pretty closely aligned and about half a dozen shots. This didn’t work perfectly but it didn’t go too badly. When you get back to the computer, you open up Photoshop. Click on File and Statistics and a dialog opens up. Select all of the files and change the option at the top to Median and check Align Images. Then send it on its way.

If the shots are good and there are enough, the algorithm will look at each shot and see the changing items – cars in this case – as the oddities. It will see what is consistent in each shot and get rid of the odd stuff. If you have it right, the cars will vanish. In this case, there were some overlaps and not enough shots but it still did a reasonable job.

Polarizer Comparison

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When I changed bodies, I had to update some of my accessories too. My old filter system was fine on a cropped body but with full frame, the filter holder encroached on the corners for the wide angle lenses. I took the opportunity to change my polarizer set up. I used to use a polarizer on my Cokin holder. This was a bit inconvenient when I was using lens hoods. Instead, I decided to get a screw in polarizer. Since most of my lenses have the same filter size, this gives me more flexibility.

I took the polarizer with me on vacation. One place where I made good use of it was in the rain forest. While it was pretty dark in the heavy forest cover, there was moisture everywhere and this meant a lot of reflections and glare. Consequently, I went with the polarizer most of the time. While I was there, though, I decided to do some experimentation by repeating some shots without the polarizer to see how much of a difference it made. You can see the with and without shots here and judge for yourself what a difference it makes.

High ISO Raw File Size

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On my previous camera bodies I had occasionally shot at very high ISO settings as a result of the lack of light. I had not paid a huge amount of attention to any secondary effects of doing so. My current cameras had a work out in some very low light when I decided to test them in some rather unfriendly conditions. When I was at home, I was running some disc backups and I found I could not get the normal number of files onto a single disc. A quick bit of investigation and I could see why. The high ISO shots had a significant increase in file size. As I understand it, RAW files, while containing all of the data from the sensor, do have an amount of compression applied. I imagine that the noise inherent in high ISO shots means that the compression is less effective as there is so much variation across pixels. As an example, a shot at ISO 320 will average at about 22Mb. The shots at ISO 51,200 are coming in at over 30Mb. At ISO 204,000, the files can hit 40Mb. That is quite an increase! Something to keep in mind when planning to shoot in very low light conditions.

Lightning Photography

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When I shot film I had a go at shooting lightning a number of times but never with any success. I would try and react to get the bolt but it was always gone. When you are using film and having a very low success rate, things get too expensive. Consequently, I gave up on it. The move to digital opened up a new range of possibilities.

My new approach doesn’t involve much skill (but then neither does using an electronic trigger). I set up the exposure to have a reasonably long shutter speed. Then I put the camera on continuous mode, plug in the cable release and lock the shutter open. Then the camera takes a steady stream of shots. Of course, when there is a slight gap between shots, you can imagine when the lightning will strike.

I used to shoot a lot from the apartment in Chicago. Set the camera up and go and do something else. Unfortunately, the heavy rains that would accompany the storm activity could result in the sky glaring out but you still had a chance. Some of the shots were okay and every once in a while you would get a really cool outcome. The Trump Tower was next to us and it would be struck occasionally but it was too close to get a good look at. You could hear it though!

Crosswind Training in the Citabria

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This Citabria was flying circuits at Hayward while I was there. The wind was pretty strong and coming across the runway so the pilot was taking the opportunity to practice their crosswind landings. A lot of wing was down into wind in order to compensate for the conditions and, while they occasionally struggled with some of the bigger gusts, they did seem to have good control of the aircraft. I guess awkward conditions are a reason a lot of flyers would stay on the ground but this one saw an opportunity to get some good practice in. Nicely done!

An Alternative to Negative Scanning

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I am in the process of experimenting with a new approach to scanning old photographs. For many years I have been using a Minolta Scan Dual III scanner. It can accept strips of negatives or slides and does a reasonable job of scanning them in. It is a bit labor intensive and is certainly not fast. Moreover, the scanner is not terribly reliable and it will often hang mid scan requiring me to restart it and close down the application before restarting that too. Since it takes a long time, I often get it running and go and do something else so I might miss the problem.

I do have another imaging tool that works very quickly. In fact I have several of them. These are my current digital cameras. I have bought a set of extension tubes to allow me to treat existing lenses as macro lenses. I have also acquired a small light pad. Cutting some card to shape means I can hold down any old negatives and view them through a hole with illumination from the light pad below. Mount a camera on an arm looking down on the pad and I now have a way to image the negative.

I am taking the images at my desk so I am able to tether the camera to the computer and use Lightroom to capture the images directly. This has actually provided me with an opportunity to drag out one of my older bodies that doesn’t get used anymore. My old 40D has been sitting on a shelf for a long time but it has come back into use for this project. It has more than enough resolution for this task. (Unfortunately, the batteries are now rather old and don’t hold a charge well so I am going to get an AC adapter from Amazon for ten dollars which should free me to scan as much as I want.)

I slide the negative into the holder and check the rough alignment through the viewfinder. Fortunately, although it took me a while to find it, the 40D does have Liveview so I can make use of that to make sure the alignment is right. I use the trigger release in Lightroom’s tether dialog to take the shot to avoid disturbing the setup. If an image needs over or under exposure, I have to remember that it is a negative so I have to use exposure compensation in the opposite sense. The shot is imported straight in the Lightroom when it is taken. The first thing that I need to do is reverse the tone curve to change the negative to a positive. A white balance correction will take out the color cast of the negative and I now have an image to work with. I have a preset for given film types that does this during the import process.

The image is now recognizable but not there yet. Now I have to do some manual manipulation to tidy it up. The sliders have to be used carefully in this case because they are now working in reverse as a result of the tone curve that I applied. This requires some thought. Exposure is still exposure but is reversed. Usually shots look a bit washed out so, what would normally by the Blacks slider is now the Whites. Shadows are handled with the Highlights and vice versa. It takes a bit of getting used to but it is not too hard after some practice. I tried using Auto Tone but it did not do a great job. I imagine the algorithms were not designed for operating in reverse!

With everything set up, I can work through a shoot very quickly. Choosing which ones to ignore and reshooting if something doesn’t look right can be done pretty much on the fly. Is the image quality great? It’s okay but not amazing. However, many of the originals are not that great either. For the majority, it actually does a pretty decent job and sets me up for something that I can do more work on if I need to. It is a big improvement on my previous approach and now I will make quick scans when I need them rather than be dreading the time involved and avoiding all but the must have shots to save time.

Fisheye Correction in Lightroom

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I have a pretty well defined routine for importing and processing my images in Adobe Lightroom. I have presets for importing images that put them in the right folders, apply copyright information and apply development presets. I can then edit from there as I go. One of the settings I have set as a default is the application of the lens correction settings. This setting deals with any natural vignette in the lens as well as some distortion. Occasionally this can be tricky if you have something close to the edge of a wide lens and it gets slightly chopped by the correction.

I discovered a more extreme version of this while processing some shots from the Lick Observatory. I had taken my 8-15mm fisheye zoom with me as I thought there might be some use for it in the telescope buildings. It turned out to be a good thing to have. When I first had the lens, Adobe had not created a profile for the lens so the shots came in uncorrected with the fisheye look I expected. More recently, Adobe have created a profile for this lens. It was added in one of the updates and, since I don’t use the lens all of the time, I hadn’t noticed.

When I was going through the shots, I noticed the wide shots had some strange distortion at the edges. I was perplexed by this and also wondered where the circular fisheye shots were because I was sure I had taken some. Only then did I realize that these were those shots and the corrections were being applied. Here are some examples of the before and after with the correction to give you a idea of what the transformation is. A pretty dramatic change. I might make use of this sometimes but I shall also have to remember switching this off when shots with this lens are involved.

Haze Filter

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The Creative Cloud version of Lightroom drops new features in to the software when the updates are installed. This is a nice thing to have happen but, unless you are paying attention, you might not be aware of some of the new features. It took me a while after the last update to learn that a new filter had been added that was designed to take haze out of images. This is a great idea. I have experimented with trying to remove the effect of haze in shots before but, because the effect varies by distance, it can be quite tricky to get something that doesn’t look totally wrong.

I have not played with the filter a lot but I did decide to try it out on a shot I took at Crater Lake a few years back. Wildfires had resulted in smoke in the air which meant the usual clear view across the lake was obscured. I thought I would see how the filter worked out. Above are the before and after shots. It is an improvement but obviously isn’t going to rescue a totally messed up shot. I did try a more aggressive setting but that looked wrong itself so this was the one I went with. We shall see if this has other uses for me over time.

HDR Within Lightroom

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The changes in Lightroom CC that included the Photomerge also included a change to the processing of HDR images. Again, the functionality has been brought within Lightroom rather than requiring the move out to Photoshop and the output file is again a DNG file. This means a smaller file than the 32 bit TIF that I was previously getting. A while back I wrote about some of the odd experiences I was having with moving these high bit depth files between Photoshop and Lightroom so a new workflow is of interest.

According to some of the publicity at the time of roll out, the new processing approach does not require as many images to work with. I have been shooting five images for HDR to date. They say that only a couple are necessary. I have tried carrying out the processing with five and with two and there doesn’t appear to be an obvious difference in the output. There is a benefit in the time taken to process the images though so this does appear to be a good improvement.

You can either let the output be automatically toned using the normal Lightroom processing functions or do it yourself. I let it have a go at first but have not liked the choices it made so have reverted to carrying out the toning myself. It is not a time consuming process so seems worthwhile to me. While I felt that Photomerge was not as capable as using Photoshop, in to case I think it is a better solution and this will be part of my workflow. Now to reset the camera to shoot fewer bracketed images!