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Please look at the anamorphic thread to see how some of those lenses were actually made in the past. Here is a picture of a computer optimized wide angle cooke triplet which should work with LCD of 17 inch wide screen format. It has 450 mm FL and 40 degrees total field of vision. I will post design information and the lens can be scaled down for use with 15 inch LCD and lower FL. Find an optician who will sell you two 75 mm diameter +0.75 Diopter lenses.
Be sure to leave a lengthwise gap in the felt to allow air to escape as you are focusing. The felt can also be used to line the inside of the tubes to reduce reflected light inside your lens. Here’s an example that uses this approach for a rather improbable 400 mm lens. Value is always important, but the range for triplet lenses is relatively narrow. We feel that the #1 model offers a great value for most people and that the #2 is great for advanced users.
Best triplet lenses Reviews
Size for size and similar focal ratios the Fraunhofer is a better design. It is slightly more achromatic and field coverage is better if AP is a consideration. The Littrow is "easier" to make, needs little specialist equipment for testing and is less sensitive to cell mounting issues. I've used a number of uncoated Littrow objectives and can't recall ghosting issues, modern coatings, if applied should overcome any. The size and focal lengths that we are dealing with with this lens takes it outside of making it with common things like eyeglass blanks or even off the shelf lenses. I don't know much about lens design or requirements, but when reading this thread one source came to mind for making custom lenses of various strengths cheaply, eyeglasses.
The way I figure it the average dot size for a high resolution CRT monitor is around .24 mm. This dot consists of three color pixels so lets say that for a lens system to accurately focus on these small objects it must be able to focus each subpixel. So we need a lens that can focus a spot size of .08 mm to be able to accurately focus the image.
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Nikon, Canon, Leica, Pentax, Sigma, Tokina, and a host of other lens makers are all striving to bring you the sharpest lenses with all optical aberrations reduced to the minimum. Because with lenses, as with life, sometimes it’s the imperfections that make things interesting. The back of the lens is treated in the same way except the sign of the radius is reversed. This means that a convex shape is a negative radius and a concave shape is a positive radius.
When a lens designer starts a design, he has a set of goals. Telescope objective designers don't care how their lens performs with light entering at a 20 degree angle, because it will be mounted in a long tube with a tiny eyepiece at the other end. Rays coming in at more than 1 degree will never make it to the eyepiece. A particular telescope objective might work okay with a 20 degree off-axis ray, but it might not. The mechanics involved in making lenses is often more challenging than the optics. One possibility is to go for a reusable, interchangeable-parts approach.
HTS 203A0 10x 21mm Chrome Triplet Jeweler's Loupe with Leather Case
Then he could make you a fancy one with coated glass lenses. I think the plastic lens blanks are available up to 75 mm diameter, but the grinding machines used to make custom lenses may be able to handle 100 mm diameter. If he can make you extra-large lenses and get them anti-reflection coated, then you will have a very good duplet. I have a 700 mm fl telescope objective that I have tried with my projector.
The good thing about building a small refractor telescope is that they’re light and portable, making them idea for taking to dark-sky sites. We create a merit function using the Zemax Optimization Wizard with attempts to minimize the root-mean-squared spot size radius calculated from the centroid, with 3 rings and 6 arms. We also insert an optimization operand, EFFL, to control the effective focal length of 50 mm. The 2D Layout shown below shows significant coma aberration in the caustic of the off-axis fields.
One is to take the plans to an optical design firm and have them custom grind the lenses for you. The other is to make the lenses yourself by hand and then have them coated somewhere with the AR coating. I was hoping that someone out there had better access and funds to try to have one made. In the future I may try and redesign the lens for use with plastic lenses that can be hand made more easily but there is no reason that the lenses could not be made by hand. I may try and come up with a method that is doable in the future.
Each of the 3 individual elements were replaced by two or more glass elements permitting f 2.0, f 1.4, f 1.2, f 1.0 and f 0.95 lenses. The Cooke Triplet 3 element all air spaced lens was a little faster and and a little sharper in its day. He had no interest in photography as such and sold his design to Taylor, Taylor, and Hobson .
This lens uses a 191 mm achromat ($9 from SurplusShed). The image on the left was shot with the imperfect optics of a homemade lens. Exploring the soft, dreamy world of DIY camera lenses in surprisingly easy.
We are not yet diffraction limited and there are certainly more steps one can take but we stop here. Any significant improvement would most likely involve lens splitting, glass choice, and/or aspheres. As one can see in the design, using only spherical elements with relative common glass choice, it performs well on- and off-axis.
This shows that astigmatism is actually the most dominant aberration with 87.3 waves of wavefront error shown by the \(W_\) term. Coma is the second most dominant with -38.9 waves of error as shown by the \(W_\) term. Remember this is just a listing of the third-order aberrations. While specific aberrations are difficult to quantify from the spot diagram, Zemax calculates specific Siedel coefficients and converts them in terms of wavefront error with units of waves. Also, I can't avoid the small apertures and diffraction.
For example, check the minimum requirements listed on each model's product page if you're looking at laptops and want one with a larger hard drive. If they're not listed, ask customer service or call the manufacturer directly before making your purchase. The finest product for you is that brand if you have your heart set on it. For instance, you should shop for a Samsung S9 phone online or at any other Samsung store if you wish to buy one. You first need to consider the product's brand name.
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While spherical aberration dominates the on-axis field. Mark, you have exhumed an ancient thread, so I don't know if you'll get many answers. I have never tried to use an ordinary triplet lens as a macro lens, but here is some speculation. The Cooke Triplet was the basis of all of the high speed lenses used in 35mm photography.
Lenses with antireflection coating are the best, but more expensive. Tell him or her it is for a projector lens, so you need uncut unmounted lenses. The pair of uncoated lenses should not cost anymore than their discount eyeglasses price.
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