Back to Basics
Derek Smith • 10 July 2020
Kaya
Photo By: Derek Smith
Hypericum
Photo By: Derek Smith
Back to Basics
Recently someone I know bought a new camera, and of course they had many questions, I had to research these to find the right answers, and the first question was:
What is Lens Focal Length?
Focal length, usually represented in millimeters (mm), is the basic description of a photographic lens. It is not a measurement of the actual length of a lens, but a calculation of an optical distance from the point where light rays converge to form a sharp image of an object to the digital sensor or 35mm film at the focal plane in the camera. The focal length of a lens is determined when the lens is focused at infinity.
Lens focal length also tells us the angle of view—how much of the scene will be captured—and the magnification—how large individual elements will be. The longer the focal length, the narrower the angle of view and the higher the magnification. The shorter the focal length, the wider the angle of view and the lower the magnification.
As an example use a short focal length 24mm (16mm* or 12mm**) to capture the interior of a room, or a landscape view.
* = APS-C crop sensor camera ** = Micro Four Thirds crop sensor camera
What is Aperture in Photography?
Aperture refers to the opening of a lens's diaphragm through which light passes. It is calibrated in f/stops and is generally written as numbers such as 1.4, 2, 2.8, 4, 5.6, 8, 11 and 16. Lower f/stops give more exposure because they represent the larger apertures, while the higher f/stops give less exposure because they represent smaller apertures. This may seem a little contradictory at first but will become clearer as you take pictures at varying f/stops. Be sure to check your manual first to learn how to set Aperture Priority for your camera, then try experimenting to get comfortable with changing the aperture and recognising the effects different apertures will have on the end-result image.
Selecting a wide aperture of f/2 would ensure that only a small portion of the image would be sharp, whereas a narrower aperture of f/10 would ensure that a greater part of the image would be in focus.
What is ISO in Photography?
In digital cameras ISO measures the sensitivity of the image sensor, the lower the number the less sensitive your camera is to light and the lower the noise in the image.
Higher ISO numbers mean your sensor becomes more sensitive to light which allows you to use your camera in low light situations, the trade-off of doing so is more noise in the final image.
An example of a situation you might want to choose a higher ISO would be photographing an indoor sporting event where the light is low and your subject is moving fast. By choosing a higher ISO you can use a faster shutter speed to freeze the movement.
What is exposure in photography?
The light meter in a digital camera calculates the correct exposure of the image based on 3 parameters: ISO, shutter speed, and aperture. This is known as the "exposure triangle". Creatively the photographer chooses 1 or 2 of these parameters based upon the subject. As an example when photographing a moving subject you may select a shutter speed of 1/500 to "freeze" the action, ensuring the the subject is sharp. In the case of a portrait in the front of a distracting background the photographer might select an aperture of f/2 to isolate the subject from the background. The choice of ISO again is an artistic choice, the photographer may choose to set the ISO to "Auto" if the light is variable, alternatively in the case of the portrait set the ISO to the base level of 100 or 200, to give a noise free image.
In the case of the portrait of Kaya, I used a lens with focal length of 90mm (60*, 45**) our location was in shadow under a railway bridge, I set the aperture to f/1.8, and set the ISO to 400. I was using "Aperture Priority" as the camera mode, with the ISO, and aperture fixed the camera calculated the correct shutter speed of 1/200 to give the correct exposure.
The photo of the Hypericum flower was captured with a 120mm macro lens (80*, 60**) ISO 800, aperture f/4, and a shutter speed of 1/60 calculated by the camera.
For further reading on the exposure triangle I found this website to be useful:
https://photographylife.com/what-is-exposure-triangle
Recently someone I know bought a new camera, and of course they had many questions, I had to research these to find the right answers, and the first question was:
What is Lens Focal Length?
Focal length, usually represented in millimeters (mm), is the basic description of a photographic lens. It is not a measurement of the actual length of a lens, but a calculation of an optical distance from the point where light rays converge to form a sharp image of an object to the digital sensor or 35mm film at the focal plane in the camera. The focal length of a lens is determined when the lens is focused at infinity.
Lens focal length also tells us the angle of view—how much of the scene will be captured—and the magnification—how large individual elements will be. The longer the focal length, the narrower the angle of view and the higher the magnification. The shorter the focal length, the wider the angle of view and the lower the magnification.
As an example use a short focal length 24mm (16mm* or 12mm**) to capture the interior of a room, or a landscape view.
* = APS-C crop sensor camera ** = Micro Four Thirds crop sensor camera
What is Aperture in Photography?
Aperture refers to the opening of a lens's diaphragm through which light passes. It is calibrated in f/stops and is generally written as numbers such as 1.4, 2, 2.8, 4, 5.6, 8, 11 and 16. Lower f/stops give more exposure because they represent the larger apertures, while the higher f/stops give less exposure because they represent smaller apertures. This may seem a little contradictory at first but will become clearer as you take pictures at varying f/stops. Be sure to check your manual first to learn how to set Aperture Priority for your camera, then try experimenting to get comfortable with changing the aperture and recognising the effects different apertures will have on the end-result image.
Selecting a wide aperture of f/2 would ensure that only a small portion of the image would be sharp, whereas a narrower aperture of f/10 would ensure that a greater part of the image would be in focus.
What is ISO in Photography?
In digital cameras ISO measures the sensitivity of the image sensor, the lower the number the less sensitive your camera is to light and the lower the noise in the image.
Higher ISO numbers mean your sensor becomes more sensitive to light which allows you to use your camera in low light situations, the trade-off of doing so is more noise in the final image.
An example of a situation you might want to choose a higher ISO would be photographing an indoor sporting event where the light is low and your subject is moving fast. By choosing a higher ISO you can use a faster shutter speed to freeze the movement.
What is exposure in photography?
The light meter in a digital camera calculates the correct exposure of the image based on 3 parameters: ISO, shutter speed, and aperture. This is known as the "exposure triangle". Creatively the photographer chooses 1 or 2 of these parameters based upon the subject. As an example when photographing a moving subject you may select a shutter speed of 1/500 to "freeze" the action, ensuring the the subject is sharp. In the case of a portrait in the front of a distracting background the photographer might select an aperture of f/2 to isolate the subject from the background. The choice of ISO again is an artistic choice, the photographer may choose to set the ISO to "Auto" if the light is variable, alternatively in the case of the portrait set the ISO to the base level of 100 or 200, to give a noise free image.
In the case of the portrait of Kaya, I used a lens with focal length of 90mm (60*, 45**) our location was in shadow under a railway bridge, I set the aperture to f/1.8, and set the ISO to 400. I was using "Aperture Priority" as the camera mode, with the ISO, and aperture fixed the camera calculated the correct shutter speed of 1/200 to give the correct exposure.
The photo of the Hypericum flower was captured with a 120mm macro lens (80*, 60**) ISO 800, aperture f/4, and a shutter speed of 1/60 calculated by the camera.
For further reading on the exposure triangle I found this website to be useful:
https://photographylife.com/what-is-exposure-triangle
Louth Photographic Society
Last night members were treated to an excellent presentation by Janice Lusby, she took us on a photographic journey around the islands surrounding the British Isles. Her photos took us around the isles of Skye, Anglesey, Isle of Man, Isle of Wight, Jersey, and the Isles of Scilly. Janice's presentation evoked many memories of visiting some of these amazing islands, I've visited Skye twice and never seen anything of it because of heavy rain, and it was a sunny August on the Moray coast when we left!! The Isle of Man was another place of memories for me, taking the ferry from Liverpool, spending a week on the island, enjoying the steam railways, trams, and the beautiful waterfalls. I first visited the Isle of Wight when I was 18 years of age, in a Ford Consul, staying in a B&B in Ryde, watching the QE2 sailing out of Southampton Water from the car park at Ryde. I've visited the island a further 3 times since then and enjoyed riding the refurbished London Underground trains, and the steam railway at Smallbrook Junction. A visit to Anglesey on a short break went by in a blur, as my partner decided to buy me a surprise zip wire experience, over a quarry at 100mph!! It was a fascinating evening, many thanks to Janice on her well prepared presentation.
Yesterday afternoon's Inter Club PDI competition, was judged by Carol McNiven Young, of Rolls Royce, Derby. It was a closely run competition, with many excellent images, and a well done to all clubs who entered, there were only a few points between the top few clubs, with the difference expanding at the bottom of the leaderboard. The highest placed images from Louth were "Willow Emerald Damselfly" by Graham Harrison, and "Hidden Secrets" by Dave Turner both attaining 19 points. Lincoln took first place in the competition with 162 points, Louth tied joint 6th with Axholme on 150 points. The very well deserved judges choice of best image was "Ethereal" by Lee Dixon, of Cleethorpes.
Good Morning All We have got back from a week away staying in the Yorkshire Dales near Reeth. It certainly was all four seasons in one week arriving in a storm with the rivers in full flow and getting better as the week went on with a frost as we left. It was a very good week for walking and taking photographs. Reading the blog you had a good week last week, not sure why the N&EMPF print exhibition video was not finished ready for us. This week, Wednesday 4th November, Janice Lusby from NELPS is our speaker showing us "Around these Islands". The following week it is Retro night where we turn the clock back to the days of transparencies, it's done in the same form as mini lectures and time will depend on how many take part, if you can let me know if you would like to take part, I have myself and Richard Hildred so far. Today, Sunday the 1 st November it is the Inter club PDI competition at Nettleham village Hall starting at 2pm, Louth have entered so it would be good if some of us attend. Regards Graham
The planned event for the evening was to have been a showing of the N&EMPF Exhibition prints, but unfortunately the link for the prints was not available. Instead Harry, and I had both prepared a talk on our respective camera systems. Many regular readers of my musings will know that I had lost my photographic “mojo” earlier on in the year, I was reassessing my photographic style, and camera equipment to recover my enthusiasm, so it was that I sold all of my OM Systems cameras, and lenses, and unknown to most in the club bought a Canon EOS R7 APS-C camera, and 4 lenses as a complete kit. Learning a new camera system has made me reconnect with photography, and begin enjoying my hobby again. In the first half of the meeting last night I talked about my journey, my camera system, and showed some of the images taken with my new outfit. After the break Harry showed some of his excellent, and inspiring macro fungi images, taken with his Canon EOS R6, and a Sigma macro lens. It was an interesting evening, and hopefully everyone enjoyed the evening, and learned something about Canon mirrorless cameras.
Good Morning All The Autumn colours at Sedbergh was one of my entries which sum up the time of year. Last week at the club we held our monthly print competition, with the categories of "Mono" and "Open". There was a very good entry with 27 prints in each subject, well done to Derek Smith for a first in the Mono and Robin Begley for a first in the Open, all the results are on our website. This week, Wednesday 28th October, all being well, I am informed that the N&EMPF Exhibition print show was a bit behind schedule, it will hopefully be finished by now but if not, Derek will let us know, and we will do mini lectures instead. Derek, and Harry have prepared mini lectures on their favourite camera systems, if a couple of other members could prepare a mini lecture on the same theme that would be most helpful. The LPA POTY deadline date is nearly upon us; they are panels of three prints as we discussed last Wednesday. If you want to enter either attend the club PDI competition on 1 st November at Nettleton village hall or bring your prints in on Wednesday and hand them to a member who is going and will take them for you. Regards Graham
Our Society held a print competition last night, the set subject category was "Mono", whereby the prints were black and white, or single tone images. The "Open" category prints consisted of any subject of the authors choice, and the judge for the evening was Grahame Dunkin. It was an exciting competition, with 27 prints in each category, the standard was incredibly high, giving Grahame a difficult time of determining the points for each print and choosing the top three prints in each category. Grahame judges very well, he giving a relaxed, and helpful critique of each image. The website Competition page has been updated with the results of the competition. Our next meeting will be held on the 28th October, and should be a showing of the N&EMPF Exhibition prints, however if the Exhibition prints are not available, I would ask members to think about giving a talk on their "Favourite Camera Systems" just showing what they shoot with, and providing a few sample images.
Today was the LPA Battle finals day at Nettleham, it was the last one in its present form, and six clubs including Louth made the final. The judge was Alan Young from Rolls Royce camera club, Derby. Alan was quite straight to the point and as he said there were so many good prints in the competition, he wouldn't be marking low and would have quite a task giving scores to the best ones. Alan was quick to see anything he didn't think was right with the prints and was looking for more than just a record photograph. Louth had a very good start with our first three prints being held back, it then didn't go so well but we did have six hold backs altogether which were Sleeping-David Whitehouse 18 points, Morning sun Whitby-Dave Turner 18 points, Hairy shield bug-Graham Harrison 17 points, Evening light Chapel St Leonards -Tony Gaskins 17 points, Cosmos-Harry Kerman 17 points and Evening Light Whitby Harbour -Tony Gaskins 18 points. 1 st place - Axholme - 256 2 nd place - Cleethorpes - 255 3 rd place - Scunthorpe - 248 4 th place - Grantham - 246 5 th place - Louth - 244 6 th place - Lincoln - 242
Good Morning, All, Last week at the club Steve West gave a presentation on the history of Louth's cinema's, Steve started at the beginning in 1896 with the original Louth Photographic Society being involved with showing films in what was thought to be Westgate Fields. Steve went through all the other locations ending up with just the one cinema now on Cannon Street. There is a report on our blog page. This week, Wednesday 21st October, we will hold a monthly print competition, with the categories of "Mono" and "Open" judged by the LPA president Grahame Dunkin. There are just over 50 prints to be judged so should be a very good night. Today (Sunday 18th) is the LPA Print Battle final at Nettleham, the judging starts at 1pm. Regards Graham
Last night, Steve West gave a fascinating illustrated presentation on the long history of cinema, and stage plays in Louth. In the late 1890s some films were shown at various locations, in 1910 a “tent” cinema was showing films on Westgate Fields. During 1913 a site was purchased of 2 retail units, on Eastgate, the retail units were demolished, and the Palace cinema / theatre was constructed on the site ready for opening in 1914. During the interwar years many plays were staged at the Palace, and Steve has collected many of the original programs from this era. The current Playhouse was constructed in Canon Street in 1921 in the “art deco” style, some poor quality housing was demolished to make way for this new cinema. The Playhouse, and the Palace both continued in operation until 1960 when the Palace was sold, and the building was converted into a Fine Fare supermarket. During the 1970s when Bingo became popular, part of the Playhouse was used as a Bingo hall, with the reception area restyled to suit the new usage. The Playhouse was converted into a multi-screen cinema when purchased by the Parkway Cinema group in the mid 1990s. Louth is extremely fortunate to have retained a viable cinema in the town, many thanks to Steve West for a very polished presentation.
Good Morning All Sand racing starts again this week at Mablethorpe, this Sunday is practice day, times are on their website. Last week at the club we held a local competition, with the categories of: "Straight out of the camera" and "Open", there was a very good entry in each subject with Tony Gaskins having the task of judging the unedited ones and Robin Begley judging the Open. There is a full report on our website but well done to Harry for first place in the Straight out of the camera and Keith Rossington for first place in the Open. This week, Wednesday 14th, Steve West will be our speaker, talking and showing PDI's on the subject of the Louth cinema. The following week will be a print competition, with the categories of "Mono" and "Open", you need to bring your prints in this week and send an email to Dave Turner with your titles. Regards Graham
