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8 Phonebox Magazine | June 2025Olney Camera Club: Long ExposureRecently we received an illustrated talk titled: %u2018Long Exposure%u2019 - given by our Club Chairman, Steven Brown, from Olney. Later, we each had a chance to try long exposure technique with our own camera equipment.Next Meetings:www.olneycameraclub.co.ukSee our %u2018gallery%u2019 and check further meeting details on our website at divi.olneycameraclub.co.uk Wednesday 25th June: Club Competition, round 2. Starts 8:00pm at Olney Centre.Wednesday 16th July: Kathy Brown%u2019s Garden & Stevington Windmill. Starts 7:00pm, meeting at Stevington.Wednesday 30th July: Talk by Anne Miles: %u2018Weather to Photograph and What. Starts 8:00pm at Olney Centre.For further information call Andy Tel. 01234 714570, or info@olneycameraclub.co.ukThe Exposure TriangleThree important, interrelated camera exposure factors for photographers: Shutter Speed, Lens Aperture & Sensor Sensitivity (ISO), are balanced by the photographer (or the camera auto-mode) to produce exposure settings. The auto-mode will try to produce a %u2018standard%u2019 exposure, whilst the photographer %u2013 who is ultimately responsible for a good image, can make adjustments to suit his own artistic intent %u2013 darker, lighter, low-key, high-key etc.We will usually try to keep sensor sensitivity at its low base setting to minimise image noise. Adjusting the lens aperture will change the depth of focus. As shutter speed is increased the sense of movement in the image will increase %u2013 moving things will get blurred, and with longer exposures you will need a tripod %u2013 or even the non-moving things will be blurred! Sadly, mobile phone cameras do not have the control we need for this.Two Differing Long Exposure ExamplesNot Enough Light: For astrophotography, we use a tripod, but the stars and planets move slowly as the earth rotates, so without a tracking motorised mount our exposure time is typically less than 30 seconds, even with lens widest aperture, to avoid blurry stars. We are still keen to have low image noise but the sensitivity needs to be increased to obtain a useful exposure. See the example image of Carew Castle with Milky Way Centre; 25 Secs, f/3.5, ISO 4000.Too Much Light: For seascape with blurred sea on bright-sunny day, we use a tripod %u2013 to keep non-moving things sharp; and set the lens aperture to f/11 for front-to-back sharpness. A standard exposure would likely make the moving bits sharp too, so we need a longer exposure time. That%u2019s not an option without disturbing other settings, so we add the equivalent of very dark sunglasses, that%u2019s a 10 stop neutral density filter. Exposure time can now be extended to several seconds using bulb mode. This resulting image gives a very different impression with its move away from reality.See the example image of Lands%u2019 End from Pordenack Point; 13 Secs, f/11, ISO 100.We thank Steve for his excellent talk, and useful technique advice.From left to right:Carew Castle by Maureen SmithRed Red Wineby Helen BillinghamPordenack Pointby Andy GailerWe also hold %u2018Social%u2019 meetings on the third Wednesday of the month at various locations.