Know Your Digital Camera Sensor
Paul Malley • 20 December 2022
The advances in Sensor technology, coupled to the vast internal micro-processor image library means that good jpeg images are frequently obtained with minimum extra Photographer's input. However, as Photographers, we try to get the best possible image, and this starts by optimising the image taking stage in the camera. My camera offers raw at a 14bit file, giving a maximum of 16.383 tones on a 30.2Mp Sensor; however, as the Sensor histogram is split into 5 equal vertical columns (see images above), these 16,383 tones ARE NOT split equally amongst them all (i.e. they do not encompass 3,277 tones in each of the 5 columns).
STICK WITH ME HERE...
Instead, the right-most fifth (the highlights) accounts for 8,192 different captured tones (that's half of the total in just one column). Moving towards the left, the next fifth represents 4,096, followed by 2,048 levels,1042 levels, and, in the left most Section where the deepest shadows reside, only 512 different tones are captured. When processing my raw files, there are only 512 tones to recover in the shadows (compared to the whopping 8,192 in the highlights), which is why boosting / amplifying them as you raise the ISO increases noise.
HOPE YOUR'E STILL AWAKE...
Rather than accept the standard metered exposure in raw, I add exposure (as shown in the metered 2 and 3 image) - as long as the highlights are not pushed off the edge of the histogram (a term known as 'clipping'). This allows me to use my raw convertor program (either Canon DPP, or the Adobe raw) to bring back the surplus of tones in the highlights, without detriment to having to increase the shadows and potentially introduce noise. It has to be said, that when using this method, my initial raw files look over-exposed, but careful monitoring of the histogram and exposing to the right without highlight clipping ensures a full capture of the tones, with confidence that the shadows are not blocked or introducing noise in post manipulation. The distribution curve of the histogram allows full recovery of the highlights, as they are not 'burnt-out'. The more I work with my histogram, the more useful I find it. This feature is one of a number of useful histogram functions, alongside Bayer Array testing, Colour Balance (RGB) monitoring and use of exposure compensation. It is noticeable in manual mode where, as the Photographer I control the inputs, especially, where subjects permit, turning auto-ISO off.
Louth Photographic Society

Good Morning All Last week at the club Derek Smith kindly organised a studio night for us all, it was a very successful evening with Derek providing all the lighting, backdrops, and booking the model. Thank you, Derek, for all your hard work organising the evening. This week, Wednesday 30th April, we are holding a local PDI competition, with the categories of "Local Events" and "Open", you have until midnight tonight to get your entries to Harry. The local is always judged by members and this week you have yours truly judging. The following week it is that time of year already when we hold our AGM and presentation night. If any members have trophies to hand in, this week please. The week after the AGM it is the first monthly PDI competition of our new competition year, Seasons and Open, you can begin sorting out your entries for that one as well now and send them to Harry after this Monday to avoid confusion. Regards Graham

Our “Studio Night” was held last night, this is an annual event, with a model being on hand for members to practice portrait, and fashion photography. This year, I wanted to try something a little different, with two sets positioning a model at one end of the room for the fashion shoot, and another set for portraits at the opposite end of the room. I tried booking a male model, and a female model for the shoot with a casting call on my usual modelling site, initially gaining interest from one male model, but unfortunately, he had to drop out. Re-advertising the shoot, yielded a female model from Rugby, and a male model from London. Where were all the Lincolnshire models? I pulled up a list of Lincolnshire models, and directly messaged several, without any response, until just 3 days before the event a female model under the name of Dahlia_Void (Megan) from Grimsby, responded and the “Studio Night” was on. Our very own talented Paul Rudd agreed to model for us, and both models did a superb job. I believe that the “Studio Night” was a success, with members seemingly able to take some excellent images of both models. Importantly, there didn’t seem to be a lot of waiting around for members to take their shots, and the models appeared relaxed. Megan was a little star, being very patient while we pointed cameras at her.

As a photographer, do you have a “style”? That’s a question that I’ve struggled with over many years. However, now that I think over what it is that makes me a photographer, I realise that being out with my camera brings me a lot of satisfaction, and none more so than working with models. My “style” if you can call it that, is encapsulated in what I call my “walkie / talkie” location shoot, which I’ve embraced for the last six years. I arrange to meet up with a model, male or female in a location, it may be a town, city, nature reserve, or a park. We walk around the location, chatting away until we find a suitable spot for a photo, I take a couple of photos then move on to the next location. The idea of this type of shoot is not to create the “picture perfect” portrait, but rather to capture a moment, some part of the model’s character. Travelling light, one camera, one lens, no reflectors, no lighting, just natural light, and a natural background. This “style” is perhaps more akin to street photography, but with a dedicated model. Here’s a sample of some of my favourite images from my “style” of photography.

Good Morning All We have just come back from a week in Northumberland, staying at Newbiggin by the sea. I took plenty of coastal photographs including many of the area's wildlife. Last week while I was away it was the monthly print competition. There is a blog on the website as well as all the results on the competition page. I really just need to congratulate Dave Turner who won both the subject and Open competition. I am not sure if Wednesday night's studio evening is going ahead yet but will let you know. Entries for the local competition, Local Events and Open need to be sent to Harry by midnight next Sunday. We judge this competition in house; I am happy to judge one subject if anyone else would like to judge the other subject? Regards Graham

We held a print competition at our meeting last night with the categories of "Curves" and "Open". Our judge for the evening was the very competent, and accomplished Diane Seddon. Diane gave excellent critique of the prints, and one of the main themes that Diane highlighted was the presentation of the prints, siting print sizes, mount sizes, mount colours, and more thoughtful cropping of images selected for printing. Definitely food for thought, and addressing those issues will improve members points scoring in future competitions. All the prints submitted into this competition were of a very high standard, however, it was Dave Turner who swept the board with 1st, and 2nd placing in the "Open" category, and 1st, 2nd, and 3rd placing in the "Curves" category, it was a well deserved placing with some stunning prints. The Competition page of our website has been updated with the full results. Thanks to Diane Seddon for judging the competition, and Dave Mann for the refreshments.

Dave Turner, and I attended the LPA Fosters Challenge at Nettleham. The judge for the competition was Sue Wilson from Clay Cross. Axholme took first place with 19 points, Grimsby 2nd, and Cleethorpes 3rd. Louth was awarded 13 points, consisting of: Damselflies Mating – Graham Harrison 4pt Saltwick Bay – Tony Gaskins 4pt The Thinker – Keith Rossington 3pt Muted Swan – Harry Kerman 1pt Pier Number 9 – Dave Turner 1pt It was an interesting competition with some amazing images, a big thank you to Dave Turner for selecting the prints and submitting our entry into the competition.

Good Morning All Last week at the club member Chris Birchmore took us back in time with old photographs and a very interesting talk on one of Louth's old shops Platts stores. Platts stayed traditional for many years but as like most of the old shops eventually disappeared along with it's upside down sign. There is a blog on our website as well to look at. This week, Wednesday 16th April, we will hold our Print competition with the categories of "Curves" and "Open" to be judged by Diane Seddon of Cleethorpes. Harry is also now taking entries for the local PDI competition, with the categories of "Local Events" and "Open". Regards Graham

Our member Chris Birchmore gave an illustrated talk last night titled "The Shopkeeper and his Assistant". Chris related details of his family origins, and family history in Louth, in particular his connection with Platts Provision Store in Eastgate. It was a very interesting talk which evoked many memories with those members who had themselves been raised in Louth. Many thanks Chris, the preparation, and talk was excellent.

Good Morning All With all this warm weather some insects are out and about to photograph, I took this photograph in our garden with a Sigma 105mm lens to get close in on the bee. It is another month now, so you need to think about your "Prime Time" project, if you are taking part. Last week at the club Brian McCarthy FRPS showed us his personal journey in photography, Brian takes most of his photographs in his shed building models with lighting and creating photographs that most of us would never think of. This week, Wednesday 9th April, our member Chris Birchmore who will be presenting a historical talk entitled "The Shopkeeper and His Assistant" specifically talking about a relatives memories of working for Mr. Platt the Shopkeeper. For those who have prints for the next competition, with the categories of "Curves and Open", you need to send Dave Turner a list of your entries and bring the prints in this week. Regards Graham

Good morning, All Last week we held our spring committee meeting, we discussed many topics including the new program which will be available to you all soon and did some preparation for the AGM. This week, Wednesday 2nd April, Brian McCarthy FRPS will be coming along to show us some more of his work. Brian is an ex-member of our club but has more recently been a member of Grimsby Photographic Society. You can also now start sending your print titles for the Curves and Open competition to Dave Turner. Regards Graham