Vision – Glasses, Contacts and Archery

Being an archer, competitive or recreational, does not require perfect 20/20 vision. E Perez asked…

I’m not sure if you’ve worn glasses before but if so, do you have any suggestions on archers who used glasses and are now switching to contacts? I’ve recently switched from glasses to contacts and my aiming is way off!

I can relate to this question, when I started shooting I had 20/20 vision, and around high school I needed glasses. I have not tried contacts yet, however it was an adjustment. Remember, the purpose of a corrective lens helps refract the light or images into in focus so you can see. Check out this website that explains how your vision works and how corrective lenses affect vision.

Wearing glasses or contacts can sometimes be a challenge for archers, since we actually stand to the side of the bow, not directly behind it. Therefore we are always viewing things on an angle, add the complexity of a corrective lens and it may be difficult to clearly focus on the target. It depends on the strength and thickness of the corrective lenses. I have a friend who can not shoot with her contacts on. The angle of the bow, combined with the angle of her contacts and she can not see her string alignment at all, which can affect your group.

Picking glasses out also presents a challenge because of the angle of the lenses and the thickness of the frames. My sister can not shoot with her prescription glasses because the frames are too large for the angle of the bow and she can not see her string alignment. If you need corrective lenses, it may take some trial and error experimenting to find out what works best for you.

I’ve recently switched from glasses to contacts and my aiming is way off!

If you are able to see the target and string alignment in focus, consider your arrow groupings.

Groups open up: Your brain could be simply catching up with your new perception, give it some time and practice. If the groups do not get better, then try shooting with your glasses on again and comparing the results.

Groups still tight; just off center: Move the sight. Even the smallest change can affect everything else, your vision is a large change.

Moved your sight; no change: Check your form, since many things can affect your your arrows including plucking the string.

Vision is important however not as important as good form. In fact, you may have read my earlier blog about legally blind South Korean archer, Im Dong-hyun, who broke the world record at the London 2012 Olympic Games. Im Dong-hyun has only about 20% vision in his right eye and only 10% in his left eye.

Your eyes can deceive you, don’t trust them – Obi-Wan Kenobi Star Wars

Your vision is important, however you may want to focus on making sure the shot “feels” the same every time, this is the key to success. For me, my coach still insists everyone warm-up with the following exercise to help us focus on feel not vision.

Close-Open-Close Warm-up 

  1. Close your eyes and draw your bow to full draw; focusing on your form. Try to make sure all your muscles and bones are in the same position with the same amount of pressure
  2. Quickly open your eyes to move the sight to the target
  3. Close your eyes and then shoot.

I hope I have provided some guidance and answered your question. If any other readers have experienced changes from moving to contacts from glasses, we would love to hear from you.

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Arrows Series – Part 8: Fine Tuning and Numbering

Now that your center-shot is right, you’ll need to continue to fine-tune your bow periodically to change as you grow and develop as an archer. Start by labelling and numbering your arrows. Labelling your arrows with your name or initials is required for tournaments and sometimes is the only way you can distinguish your arrows from someone else’s; especially if they have the same nocks, shafts and fletchings.

Numbering is a good idea so you can track your arrows, if you have a single stray arrow. If the stray is consistent on every end and the number is the same, it may be that something is not right with that arrow.

Once you know your arrows and can track them, you can further tune your bow by adjusting various components such as the tiller, plunger, nock height etc… . You can perform some or all of these various tuning test to help tune your bow for maximum performance.

Paper Tuning Test: Tuning test involving setting up a piece of paper on a frame, stretching the paper taught, and shooting field-tipped arrows (not broadheads, which will affect the arrow flight) through it starting about 6 ft away.

Bare Shaft Planing Test : Tuning process were one shoots a bare arrow (shaft with no fletchings) for comparison with fletched arrows.

Walk-back Test: Tuning process where groups of arrows are shot at increasing distances to give a useful combined test of both centre-shot and button tension.

Check out these two very useful resources: Easton Tuning Guide and Tenzone’s Bow Tuning test documents: for instructions with these tests and many more.

As you develop as an archer you will need to make changes and tune your bow. Remember that making multiple adjustments at the same time can be hard to track and can be very confusing. It is important to only make one change at a time and test again.

This concludes the Arrow Series; Thanks and good shooting.

Arrows Series – Part 4: Spine, Flex and Stiffness

Before we discuss the topic of arrow spine, for proper safety and best performance, arrows need to match your entire bow setup. If you change draw weight, draw length, limbs, riser size, etc. this will affect you arrows. You may need to adjust the arrow length or require different arrows.

Arrow Myth:  An arrow is always straight.

Arrows SHOULD be perfectly straight when not in motion. However, when an arrow is released the force applied from the string causes the arrow shaft to be compressed against the resistant static weight of the arrow point and therefore bends.

Newton’s First Law of Motion: Every object in a state of uniform motion (rest) tends to remain in that state of motion (rest) unless an external force is applied to it.

Since the force applied is greater than the  resistance (weight of the tip), the arrow is propelled forward, and the shaft continues to flex and oscillate as it straightens itself. Arrow shafts that are either too stiff or too flexible will not fly well and will impact the accuracy of your shots or fail causing damage and/or injury. Therefore, we need to manage the flex properly so the arrow does not make any contact with the bow, or your arrow flight will be affected.

Important Tip: Arrow spine refers to the arrow shaft’s degree of stiffness (how much the arrow resists being bent) and is called spine deflection.

Basic Rule 1:  Shorter arrows act stiffer and longer arrows act more flexible.

Basic Rule 2: Powerful bows require stiffer arrows and less powerful bows require shafts that are more flexible.

Basic Rule 3: The heavier the tip equals greater the resistance, therefore the greater amount of compression.  So, a heavier tip causes the arrow to flex more and a lighter tip increase the stiffness.

According to the American Society for Testing and Materials (ASTM) the modern standards (ASTM F2031-05) an arrow’s official spine deflection is measured by hanging a 1.94 lb. weight in the center of a 28″ suspended section of the arrow shaft and is used for aluminum and carbon fiber arrows. (I believe original AMO standard has a basic guide to use for wood arrows spine determination and uses of 2 lb. and 26” section for standard measurement.) The actual distance the 1.94 lb. weight causes the shaft to sag down is the arrow’s actual spine deflection

For example, if a 1.94 lb. weight causes the center of a 28″ arrow to bend down 1/2 inch (.500″) the spine deflection would be .500″.  Stiffer arrows will bend less and more flexible arrows with bend more.

Almost every arrow manufacturer has its own numbering system and there are no universally agreed spine sizes among the various arrow manufacturers. Simply, the lower the deflection measurement equates to a stiffer arrow and higher the deflection measurement the more flexible the arrow. Manufacturers can number, size, and market their arrows anyway they want, as long as they provide the deflection data and test using the industry standard method.

Fortunately for us the engineers have already done the math for us and manufacturers provide spine selection charts. You are able to select an arrow based on your draw length and draw weight.

So when selecting arrows a good rule of thumb is that lighter draw weight, shorter draw length and/or lighter tip weight equals LESS arrow spine OR heavier draw weight, longer draw length and/or heavier tip weight equals MORE arrow spine.

Competition Baby Powder

This past weekend, I participated in the Ontario Spring Classic held at Woodlands Park in Toronto, Ontario. Toronto just happened to have very hot and humid weather during the tournament.

Heat and humidity can affect your arrow flight. Humidity can cause your arrows not to spin as quickly leaving your shot grouping lower since they do not gain as much distance. Heat affects the archer too with hot and sweaty hands. Sweaty hands affect your grip on the bow possibly changing your point of power and the heat causing your hands to swell which in turn affects your feel for the string in your fingers. Check out my previous blog about other effects of various weather conditions.

 Weather is a great metaphor for life – sometimes it’s good, sometimes it’s bad, and there’s nothing much you can do about it but carry an umbrella.  -Terri Guillemets

This year I packed baby powder, something that every competitive archer needs to bring with them to every outdoor competition.

A little baby powder on your…

…under your anchor point will help allow your hand ride along your chin smoothly

…inside of your string arm keeps your arm from becoming too sticky keeping your draw and release smooth.

…bow hand helps deal with sweaty hands that can affect your grip of the bow

… string fingers to allow your fingers to have a good grip on your finger tab making it easier to control your drawing and releasing of the string cleanly.

…cheek bones under your eyes, if you wear glasses or sunglasses, will help prevent them from fogging up.

The Ontario Spring Classic is a two-day tournament with high-performance archers including past, current and future Olympians hopefuls with the winner in each category receiving $500.00 prize money. This open tournament is a great way to measure your development against some of the best archers in Canada. If you are ready to take the next step in competition in Canada, I suggest you plan on attending next year and pack a little baby powder just in case.