For an interesting, entertaining and informative analogue photo site check out www.theonlinedarkroom.com
For an interesting, entertaining and informative analogue photo site check out www.theonlinedarkroom.com
The Beluga transports Airbus wings from British Aerospace in Broughton near Chester where they are manufactured, over to France. I live about 10 miles from Broughton, right under the Beluga flight path and the plane is a regular sight at low altitude. Once did some work at the British Aerospace and witnessed the plane taking off. It is difficult to appreciate the size of the plane until you get close up!
After using Nikon DSLR's for most of the last 10 years I have decided to get heavily back into film in my retirement using all of the film gear I amassed during the late 70's to late 90's all of which is still in great shape. All formats from 35mm through 6x4.5, 6x6, 6x7 to 5x4. Just finished converting my spare room into a fully professionally equipped darkroom. Can't wait to get back to it, but current material costs are a bit of a shock!
I have seen similar things to this used to clip a bag of rocks to the centre column of a tripod to give extra weight and stability.
I used a D40 for a few years and found it a great camera. With just 6 megapixels it produced pin sharp A3 colour prints every time provided best use was made of the frame. Don't expect to make large blowups from a portion of the photograph as it will pixellate, so fill the frame. I now use later Nikon's and have gifted the D40 to my 12 year old grandson who is just starting out and he is producing some great shots with it. As with all Nikon's build and optical quality is superb. Go for it!
Once had a similar problem. I solved it by warming the locked filters on a radiator for half an hour, then placed filters foremost down in a saucer containing about 5mm depth of cold (refrigerated) water for a few seconds. The foremost filter contracted and loosened after a few seconds. Can't guarantee it, but it worked for me.
The Win 8.1 start button reinstated by Microsoft has none of the functionality of previous incarnations. Google 'startisback', this only costs a couple of pounds (don't know how much in dollars) and restores ALL of the functionality of the Win 7 start button as it uses the existing but disabled code embedded in older versions. I hate 8 and have been using this for some time with no problems - its worth ten times the price!
Jim
If you are seeing a reflection of the lights they are too close to your lens axis. You need two identical lights placed either side of the document being copied away from the lens axis and angled at about 45 degrees and preferably incident light metered. Try using black card with a hole cut for your lens, and take the pics in a dark room. This has always worked for me.
NormanHarley wrote:
That's a bunch of hyperbola :-D (What? A little mathematical humor seemed appropriate. :lol: )
thanks for injecting a little humour. I still think this discussion should have been held in a good bar!
wouldn't it be great if we were all sitting in a bar getting wrecked and having this discussion!!!
There is no 'cone theory', just a simple demonstrable fact that a lens will produce a cone of light that comes to its sharpest focus at the point of the cone (try a lens, a candle, a sheet of tracing paper and a puff of cigarette smoke). Moving the focal plane will not alter DOF, just the point of sharpest focus. I am sure there must be some obscure physics formula which explains it all but I don't know it!
Sure, distance from optical centre of the lens to edges and corners of the film/sensor is an issue, but one which has been addressed by the use of compound lenses with elements of differing refractive properties, asphericals etc., but image quality still falls off to the extremes, mainly due to coma, colour dispersion etc. and, since the inverse square law applies, to exposure also. In response to a previous correspondent, I am not a geek, just a retired pro of almost 50 years experience with degree level qualifications and extensive teaching experience at college level. I told myself not to get drawn into a convoluted discussion but WTF. Kindest regards to all!
This seems to have gotten out of hand! Every part of the lens contributes to every part of the image. An image of a point source of light would be projected by the lens onto the film/sensor plane as a cone of light - where the point of this cone of light is at the film/sensor plane the image is at its sharpest focus (though still not a point - no lens is that perfect! - the image formed is known as a 'circle of confusion').
If the point of the cone of light falls in front of or behind the film/sensor plane it becomes a section of the cone - a larger circle of confusion. Basically a smaller aperture means narrower cone so circles of confusion are correspondingly smaller so focus falloff is not so pronounced. Hope this helps!