DIGISCOPING WITH YOUR SPOTTING SCOPE

It’s Friday and time for our weekly shoot-the-shit. Outdoors enthusiasts are prolific users of magnified optics. Everything from monoculars to large spotting scopes are on their list of must have kit. If you are a tactical rifle or long range precision shooter using a spotting scope is not an option. But, how about combining your smart device or digital camera with your spotting scope to document interesting land formations, wildlife or a competition. Enter the topic of digiscoping. All shoot-the-shit rules apply.

Digiscoping, is the hobby of using an optic in front of your tablet, phone or digital camera to extend their focal length. There are numerous approaches ranging from complete farce to Cadillac solutions that don’t make sense unless you are picture taking for National Geographic or The Smithsonian. So, our focus today is how the average man gets into digiscoping and achieve excellent results within a reasonable budget.

What you need to digiscope…

  1. digital camera or smart device
  2. digiscoping camera adapter
  3. spotting scope
  4. tripod

Digital Camera or Smart Device – In 2016, chances are you already have one or both of these so you won’t need to go out and buy something else. However, what you plan on using for taking photos along with your selection of a spotting scope will drive what type of digiscoping adapter you’ll need. In the digital camera world there are basically two broad categories, the point and shoot and the digital single lens reflex (DSLR). Point and shoot cameras have fixed lenses while the Digital SLR has interchangeable lenses and sights through the lens for greater flexibility. Point and shoot cameras will normally top out at around $400. DSLR cameras can run up to $5000 for just the body, for professional grade equipment. The smart device takes two forms the phone with built in camera or the physically larger tablet with a camera. Image size for smart devices generally top out at 8 mega pixels, although 12 mega pixel versions are entering the market. One last piece of information before leaving the camera. Pixel count does not translate to resolution, it pertains to size. A 24 mega pixel camera produces a larger RAW image. Resolution is a function of the glass you’re shooting through.

Spotting Scope – here you have a very wide range of choices, but not all are created equal and I’ll say it right now that you don’t need a Leica or Swarovski to achieve excellent results. Without getting into the straight or angled eyepiece discussion, there are two types of spotting scopes those with removable or interchangeable eyepieces and those with variable power fixed eyepieces. If digiscoping is your principal reason for buying a spotting scope, your best option is to take the removable or interchangeable eyepiece route. You’ll pay a higher price, but you’ll end up with a system that performs very well for you. I’ll give you the why a bit later. If you elect to go with the fixed eyepiece spotting scope it will probably be variable power, for example 20x – 60x, and you’ll want to confirm with the retailer if the manufacturer has a camera mounting adapter for the specific model you’re considering.

Earlier, I said that the spotting scope / camera combination drives your choice of  camera mounting options. Here’s how it all works.

  • The universal approach to attaching a smart device to a spotting scope is to use a device that clamps around the eyepiece; then using vertical and horizontal alignment screws, the operator positions the camera lens at the center of the spotting scope eyepiece.

  • If you’re using a spotting scope with a removable eyepiece, you’ll need to purchase the camera adapter from the scope manufacturer. In addition, you’ll need a T-nut, which is camera mount specific, for example Nikon or Cannon. The T-nut attaches to the spotting scope camera adapter allowing the operator to mount the camera body directly to the spotting scope. This method of camera attachment provides the best results and virtually all professional level work is done using this arrangement. It delivers the crisp sharp focus needed for exceptional quality. It’s also the more expensive approach.

  • If your using a spotting scope with a fixed eyepiece, you’ll need a camera adapter that threads to the spotting scope body over its eyepiece and open on both sides so the operator can adjust magnification levels with a variable power eyepiece. Although this system produces excellent images, sharpness does suffer a bit because the camera is interacting with more levels of glass.

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Tripod – last but not least is the tripod and tripod head. This is the weak link and the brutal truth is that if you don’t have a rock solid support, the spotting scope / camera system will vibrate in wind, or from operator use, resulting in poor image quality. Irrespective of equipment used, vibrations at magnification levels of 15x to 60x will destroy image quality so for that reason I recommend using, at least, a Manfrotto tripod with a head that’ll support 17 to 18 pounds. The thirty-nine dollar Vivitar tripods work well for low light point and shoot work but not for digiscoping.

Taking the Photo

All of the photography basics of lighting, composition and exposure apply. Digiscoping with a smart device or point and shoot camera is easier for the very simple reason that you are not replacing the camera’s lens with a spotting scope; therefore, all of the exposure options like aperture priority, program mode, auto exposure and auto focus still work. When using a DSLR camera, you are replacing its lens with a spotting scope so none of those same features work. When digiscoping with a DSLR,  you need to shoot your photos using manual exposure control,  and focusing is done by focusing the spotting scope or in some models the camera adapter.

Exposure control through a DSLR while digiscoping is limited for the following reason. When you remove a camera’s lens you lose the ability to adjust aperture, this is a setting that determines how much light is allowed through the lens. It also influences depth of field. So, when shooting through a spotting scope, in manual, you control exposure through a combination of ISO and shutter speed, and for any given subject and lighting condition there’s only one or two settings that will render a quality detailed image. ISO is a measure of light sensitivity and shutter speed determines the duration of the exposure. The higher the ISO the more light sensitive the image becomes. The faster or slower the shutter speed,  the lower or higher  the exposure time respectively.

Another anomaly when shooting through a spotting scope is greatly reduced light transmission, so you’ll need to use a higher ISO. Most DSLR’s have an Auto ISO feature but I prefer to set ISO manually in a range of no less than 200 but no higher than 1600. I use shutter speeds of no less than 1/60th of a second but no faster than 1/640th of a second depending on subject matter and lighting conditions.

If you’re using a DSLR to digiscope, consider developing a dope sheet (in photography parlance a “contact sheet”.) For example…

  1. Start at an ISO of 200 and 1/60th and step through shutter speed up to 1/640th. Examine each image to see how it changes through that sequence.
  2. Nest, move to the next higher ISO value, for example, 400 and setting your shutter speed to 1/60th and step through again. Once again examine the images.
  3. Continue all the way up to the highest ISO that you want to develop shutter speed dope for.
  4. You can continue this process as far as you wish, but I would avoid ISO settings greater than 1600 because they reduce image sharpness. Extremely high ISO values and fast shutter speeds degrade image quality.
  5. Lastly, remember that high magnification long range shots will be significantly lower in quality because of atmospheric effects like mirage. This is true whether you are shooting through a Bushnell spotting scope or a Leica.

Digiscoping, is a great way to enjoy the outdoors with friends and family so check it out, you’ll be glad you did.

Have a great weekend! Weather permitting get out and spend some quality time with your friends and family.

 

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