Science Olympiad held at IPFW
Eight teams participated in the Science Olympiad competition at IPFW Saturday. Chess Traps #5: Ruy Lopez Berlin Defence Trap (Fishing Pole)
This super-sized griddle is great for any meal. It can cook up to 50% more food than other jumbo griddles. Premium nonstick surface for stick-free cooking and easy cleaning. Slide-out drip tray empties easily. Fully submersible with the heat control removed. Control Master heat control maintains proper cooking temperature automatically. Huge cooking surface! Cooks as many as 12 slices of French to…
Scrap Bowl holds 2 qts of scraps and includes a brush/scraper that fits in the front pocket. Fits under the counter, over the drawer or door. Saves countertop space and time!….
Tags: Photography , Cameras , which is better , film , digital , low light
More than once, I’ve encountered folks who are unsure that a digital camera can equal the capabilities of a film camera. And in some senses, they have a right to be concerned. But overall, the results are clear – modern profession digital SLR cameras now have a big edge.
So, what’s the difference you may ask?
Film SLR Cameras
1. Low light capabilities are determined by film speed – the higher the number, the lower the light they can handle. Even with professional film, grain goes up considerably as you increase the film speed. That being said, the actual grain on a film print can be desirable (and digitally duplicated) for some settings and tastes.
2. Your resolution is limited by your film. The better the film you purchase, the better it’s capability to be blown up, but with any 35mm film, enlargements beyond 8×10 will lose their crispness.
Digital Point and Shoot Cameras
These cameras often give digital photography a bad name. Outside, with good light, the photos look great, but everyone has seen a digital photo where the person is either extremely dark, or glowing. The color doesn’t seem to be great, and anytime you take a night time shot, the background is pitch black. Here’s why you shouldn’t do most shoots with this type of camera.
1. Small image sensor. Unlike your film or digital SLR, the sensors on these cameras are a fraction of the size, enabling a compact camera. But you lose a lot when you make this compromise. Add a high megapixel rating, and the problem is compounded. Simply put, these cameras will have much more noise and less clarity whenever you encounter anything but bright light.
2. No external flash. Having only a small onboard direct flash makes for photos that are either washed out or too dark – if you have multiple subjects, sometimes you’ll get a bit of both.
3. No interchangeable lenses – having only one fixed lens means usually you have a high aperture (which doesn’t allow lots of light in) as well as issues with wide angle and zoom shots. And as a note, never use digital zoom – turn that feature off.
Digital SLR Cameras
Sigital SLRs have come a long way in the past 15 years. From being an expensive novelty, to professional mainstream. Even in the past 6 years (since I started our business), the gains have been noticeable and wonderful. I started with a 6.0 MP Canon that worked well, but still didn’t handle low-light scenarios as well as a nice film SLR. Today, we shoot with a 21 MP Canon that blows even your high end film cameras out of the water in both resolution and low light capabilities.
1. Bigger image sensor. Whether you are shooting a 4/3 sensor or a full size sensor with your SLR, it is many times larger than even your best point and shoot cameras. This allows for a larger spacing between pixel sensors and makes for much better low light capabilities.
2. Better resolution. I shoot a Canon 5D MkII which shoots 21 MP images – and at that size, I can blow my photos up to poster size without loosing clarity. Do that with a 35mm negative, and you would have a very soft image.
3. Interchangeable lenses. Having this capability, like in the 35mm SLRs is wonderful. It allows you to have a variety of lenses catered to your exact needs – whether it be low light, long range, or wide angle shots.
4. External flash. This is one of the biggest components of a good photo. Having an external flash allows for so much more lighting options – far improved over the point and shoot.
Was the Article Useful?
I hope you enjoyed the article! Please rate it at the following link, your feedback is highly appreciated:
People use MiNeeds.com to get competitive bids from local professionals, such as: photographers, lawyers, home contractors, wedding services, accountants, web designers, movers, etc.
By simply posting your service request, professionals will come to you with offers. Don’t waste time calling around and negotiating. Instead, have professionals come to you with proposals. You can sit back and relax while comparing offers and reading reviews. It’s free!
The new Gemini-20 milligram scale offers a 1 milligram readability with a 20g capacity. The removable stainless steel weighing platform makes removing samples easy. Great for weighing precious gems and other valuables. Includes case with weight. All scales backed by our 10 year warranty….
100 Gram Scale Calibration Weight ~ NEW~ ChromeCheck the accuracy of your triple beam or digital scale with this 100 gram chrome plated calibration weight. OIML Class M1 Accuracy of 10mg (.010g) The weight measures 1 1/2 inches high by 1 inch wide, and it is brand new and unused….
Total Blender is the all-in-one appliance that makes smoothies, fresh juice, ice cream, milkshakes, cappuccinos, margaritas, soups, sauces, bread dough, dressings, salsas and more! It replaces up to 9 other appliances with one fast easy-to-use machine, at a fraction of the cost. Commercial Quality. You have seen the unique square jar before; for years blending professionals have used Blendtec mach…
Winchester 22-108644 Deluxe Game Cleaning Kit illegal in Massachusetts?
I want something to my cousin for Christmas and it seems to just be what you want, but the site says something about not being able to send in Massachusetts and consult with national laws. Does anyone have any idea if this is legal in Massachusetts, or even how I know?
responsibility for cleaning up the game is not illegal in one State which are kitchen knives, but nothing …..
The OXO GOOD GRIPS Salad Spinner family is growing! The Little Salad & Herb Spinner, a small version of our big Spinner, is perfect for drying salad for two, herbs or berries. The Little Spinner features our patented pump mechanism that makes it easy to spin salad by simply pressing the soft knob. Our patented brake lets you stop the basket to unload it, and a non-slip ring keeps the bowl steady o…
This cordless kettle lifts off its 360-degree swivel base for easy filling and pouring. With its traditional kettle design and modern stainless steel finish this kettle is perfect for home, office, or dorm. This powerful unit boils water for tea, hot chocolate, or instant foods….
Made from high-carbon, cutlery-grade stainless steel, these well-made shears are great for a variety of uses–from cutting pizza to cleaning just-caught fish. They combine a straight edge with a serrated edge for maximum versatility. Plus, this handy kitchen tool’s bonus features are numerous. A lid lifter pries under rolled metal lids to raise them quickly and easily, while its unique handle desi…
Slurpy slurp! The Teletubbies’ favorite friend is the Noo-noo! This friendly vacuum cleaner is very good at tidying up after Tinky Winky, Dipsy, Laa-Laa and Po when they make a mess, but sometimes he just can’t help being naughty! It’s a messy day to play and giggle with the Teletubbies and the Noo-noo!…
It was directed with energetic skill by Top Gun Tony Scott, but this breathtaking 1993 thriller (think of it as an adolescent crime fantasy on steroids) has Quentin Tarantino written all over it. True Romance is really part of a loose trilogy that includes Reservoir Dogs and Pulp Fiction, with a crackling Tarantino screenplay that rides a fine line between raucous comedy and violent excess. Christ…
A must-have for every pastry chef, this thick but flexible silicone baking sheet acts as a non-stick work surface, needing no grease Freeze or bake with it: withstands temperature from -40 to over 480F Great for all your chocolate & sugar work Can be reused thousands of times SilpatCare Instructions Handling Work with Silpat ona flat surface with the smooth side facing up (Silpat logo up). Check t…
*****CD IS PRESSED”MIXTAPE STYLE”****LIMITEDQUANITIES****WITH FRONT AND BACK ARTWORK, AND DISC ARTWORK****ARTIST MANUFACTURED***NOT A BOOTLEG***
RARE LATIN NORTHERN CALI RAP…
Protec antimicrobial treatment inhibits up to 99.99% of black mold growth and prevents the growth and migration of mold, fungus, and other bacteria. Removes minerals and pollutants from water. Air washing layer helps capture dirt, dust, and pollen. Fits Honeywell model…
Variety is usually the first thing that shoppers notice when browsing through diamond abrasive products.
Not only are abrasive power tool accessories available in countless shapes (like wheels, cups, and core bits), but the list of qualities and specifications that change their performance is also long.
On top of that, manufacturers don’t always advertise their diamond products with detailed specifications. Often, diamond products only indicate the type of work they are meant for, not the design details that suit them for the work.
In either case, knowing specification details and how they relate to tool performance is the best foundation that shoppers can have when matching diamond abrasives to their work.
Technical know-how helps tool users make the best purchasing decisions, regardless of how products are labeled and advertised by manufacturers.
Diamond abrasives are made by adhering diamond particles to a base material with a bonding agent. Sometimes the bonding agent also serves as the “base” of the product, and other times they are separate. Qualities related to this basic construction can drastically alter the product’s performance, and are discussed below.
Because diamond abrasives are expensive, most purchasing guidelines for them aim to maximize cost efficiency. This is done by correctly matching a diamond product’s durability to the kind of target material and work it will be doing.
Bond Types
Understanding the importance of bond type and bond hardness (discussed below) in diamond abrasives requires knowing how they wear and stay sharp.
Simply, (with the exception of “dressing”) they stay sharp by wearing.
Friction, pressure, and heat during use causes dull, top-layer diamonds to pop out of the bond matrix, exposing fresh, sharp diamonds beneath.
The rate at which diamond abrasives wear/self-sharpen depends on a balance between material hardness and the strength of the bond holding the diamonds in place. The idea is to use blades that wear at a rate that replaces diamonds just as they begin to dull, maximizing the quality and speed of cutting being done, and durability.
There are three major types of bonding types used to manufacture diamond abrasives: metal matrix (sintered), resin, and electroplated.
Sintered/Metal Bonded
Metal bonded diamond abrasives are the most commonly used, because, generally speaking, they are the most durable and very general purpose.
Diamond grains are bonded to a metal matrix in a sintering process (heat and pressure) that layers diamond grains throughout the material. Sometimes this diamond/metal matrix is bonded to a separate base (usually steel), and sometimes the matrix also serves as the base.
Because of their durability, metal bonded diamond abrasives are the most cost effective unless the specialization of resin or nickel bond types is needed. Although this bond type is generally “universal,” metal bonded abrasives still vary between one another in terms of hardness and other factors, and need to be carefully matched to their applications.
Most common metal bond grades (bond hardness): L, N (most common of the two) dressable the most durable and universal
Resin
Construction of diamond abrasives using resin as a bonding material is very similar to the construction of non-diamond grinding wheels that use a resin agent.
Resin is a much softer bonding agent than metal matrix, and allows diamond particles to escape the product more readily. This means that resin bonded diamond abrasives do better at staying sharp than metal bond types, cut and remove material faster, are cooler cutting, are “dressable,” and great for precision grinding and cutting.
The disadvantage is that resin abrasives will wear much faster. One, this restricts their use to materials in the soft to medium range.
Two, their lower durability means that it’s even more important to select the right resin bond hardness for the target material. Otherwise, users will be going through products too quickly for the benefits of resin bonded diamond products to be cost effective.
Most common resin bond grades (hardness): H, N, R
dressable
fast, cool cutting for precision work and finishing
Electroplated (Nickel Bond)
Electroplated diamond products use a thin sheet of nickel to bond a single layer of diamonds to the product (usually blades).
This bond type is soft and wears very rapidly, is not dressable, should be restricted to softer materials, and is usually only cost effective for minimal use.
The advantages to this bond type are that nickel bonded diamond products are very abrasive and fast cutting. They can also be stripped and re-plated at minimal cost to the owner.
Most common nickel bond grades: N, P, R
not dressable, but can be stripped and replated
maximum particle exposure, and high stock removal
Bond Hardness
Correctly estimating the needed durability of a diamond abrasive is the most important purchasing consideration, because of their expense.
Bond hardness (along with bond type) is the most determining factor for durability, and must be matched correctly to material hardness. The general guidelines are these:
1. Softer bonds for harder application materials. Harder materials will wear (dull) diamond particles faster. This means that, in order for the product to stay sharp, a softer bonding agent is needed to allow diamond grains to escape the matrix more rapidly.
Too hard a bond will cause very slow cutting, and risk heat damage to the abrasive.
2. Harder bonds for softer application materials. Softer materials will not wear diamond particles as quickly. This means that particles are usable in the abrasive longer, and do not need to be ejected from the bonding matrix as rapidly in order to ensure efficient cutting. Too soft a bonding material will cause unnecessary wear, because still-sharp diamond grains will leave the product prematurely.
Bond hardness is expressed on an alphabetical scale, progressing from soft to hard from A to Z.
Again, it is important to mention that shoppers will still have to choose a specific bond hardness, even between diamond abrasives of the same bonding type.
Diamond Grit Size (Mesh Size)
A specialized mesh is used during the manufacturing process of diamond abrasives, serving two purposes:
1. The mesh sorts diamond grit sizes within a specific range, and
2. It positions the diamond grains for bonding.
Because of this, “mesh size” and “grit size” are interchangeable terms when talking about diamond abrasives.
A high grit number corresponds to smaller diamond grains, meaning a finer abrasive. A lower grit number means larger, more corsely-cutting grains.
Particularly with diamond abrasives, grit size affects the “micro damage” to the surface finish. Although the cutting power of a lower grit number might be attractive, the roughness of its cut may not be the best thing if a very fine finish is desired in the end. Diamond abrasives aren’t always labeled with their exact grit number, sometimes advertised as simply being of coarse, medium, or fine grit.
Below are the grit number ranges that generally make up these categories:
Coarse: 20-80; (masonry, concrete, and stone)
Medium: 80-200; (glass, ceramics, and quarts)
Fine: 200-400; (slow grinding, and fine polishing)
Diamond Concentration
The concentration of diamond grains in their bond matrix can be altered in diamond abrasives to achieve different effects in performance.
Concentration is expressed much like grit size, using a system of “round” numbers that represent specific volumetric distributions of diamond grains. For example, concentration number 100 is typical for diamond abrasive products, and it corresponds to an exact measurement of 4.4 carats (of diamonds) per cubic centimeter, or, 25% concentration of diamonds by volume in the bonding matrix.
General guidelines about diamond concentration:
Higher concentration will make blades more durable and produce a finer finish, but it will also cause slower cutting speeds because of increased friction. Abrasives with a lower diamond concentration are generally better for hard materials, and they cut much faster.
Diamond Grades and Types
Just like diamonds that are used in jewelry, abrasive diamonds come in many types and grades.
The nomenclature and categorizing systems for these features are excessively technical, extensive, and often confusing.
Changes in diamond type and grade do affect diamond abrasives, but only in a secondary way when compared to the other, more critical, features and design differences discussed in this article.
Because of the depths of these topics and their relative unimportance, we won’t delve any further into the subject. However, we make this brief mention to acknowledge that shoppers will eventually encounter these terms, and invite them to investigate diamond grades and types if their applications demand it.
Remember, shopping with durability and cost-effectiveness in mind is the way to go with diamond abrasives. The hardness of the bond and other product features must be balanced with material hardness and the type of work being done.
To help make the search easier, shoppers visiting eReplacementParts.com can narrow diamond abrasive searches by selecting what kind of target material they have in mind. This way, the only products that display on the page are those that combine features for the selected application material.
About the Author
Written By: Justin Larsen Professional writer for eReplacementParts.com Follow Us on Twitter | Become our Fan on Facebook
How to Make a Custom Knife Blade : Custom Knives: Profiling the Blade
Cuisinart Smart Stick Hand Blender – 200W Blend ingredients right inside pots, pitchers, bowls, or the clear plastic beaker that is included with the Cuisinart Smart Stick Hand Blender, which is available in your choice of color. A powerful 200-watt motor operates with an easy one-touch control. Blend drinks, puree soup, and mix crêpe batters in seconds! The blender features a ergonomic grip that…
Slice and julienne vegetables evenly into thick or thin slices with ease using this folding mandoline slicer from Progressive. This versatile and efficient gadget uses three double sided cutting blades to provide six cutting option; thin slice, super thin julienne, medium slice, thin julienne, thick slice, and thick julienne. The blades are made of stainless steel for edge retention and efficiency…
By the mid-’80s Dire Straits were a platinum band dismissed in their native England as safe, yuppie rockers, yet the original quartet’s lean, guitar-driven music struggled to find a label home when first recorded in 1978. Mark Knopfler offers craggy vocals, literate blues-based songs, and sinuous, virtuosic guitar work. He melds keening solo lines and rapidly picked fills and dodges the synth wash…
