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Chalo & Dave's Calamus Notes

Digiscoping Or How I Saved $68,000

 

First a little definition, digiscoping is the art of hooking a telescope up to a digital camera. I haven't done it, because my digital camera can't. Mine is too expensive. The cheap cameras can take full advantage of this art. With this disclaimer, which will make my readers wonder if Barkin has finally lost all his nuts and bolts, I shall proceed. My digital camera is a duplicate of a regular film camera, so while I can hook a telescope up to it, there are actually advantages to the much, much cheaper digital cameras. More on this later.

A little warning: I do not know all there is to know on this subject. I am not an expert. But in the course of spending huge gobs of money, large amounts of time and effort, I've picked up quite a bit of knowledge. Nothing in this article is incorrect. There's just more to know...

I have become a photographer, and in particular, a nature photography buff. I have the equipment. Good camera, expensive lenses and patience (that most highly required resource). I loved browsing through books and magazines showing these incredible close-ups of wild animals, almost it would appear, breathing into the photographer's lens.

Looks easy. Many times I have tracked though wild country fully equipped to match these wonders. Sure, squirrels and pigeons make good subjects, hardly wild animals. For months I've been trying to shoot some pictures of two kingfishers. I know which forest this happy couple lives in and often attempt to stalk them. They will fly by at 100 m/h giving me all the time in the world to open my mouth and curse in many different languages. Or take the blue heron who lives in the same river valley. He lets me approach to within 100 yards before beating his majestic wings in a fond farewell. And so it has gone. Success after success as one blurry, indistinct image follows another.

I show these pictures to friends. "Look closely, see that little blue spot about 1/4 of an inch wide, that's a blue heron," I say with pride of work well done. Let me pause and point out that I have hundreds and hundreds of pictures of my dog, who is a wild animal if ever there was one. At any rate I make a trip up to this river valley twice a week. Problems such as the ones described above do not affect my essential determination, true grit and stupidity. Late last summer as I was driving home I paused by the side of a lake which is on my direct route, to take some images of the lake and a small island near the opposite shore. I had my Sigma 28-300 lens, zeroed in on the island, and discovered to my surprise and shock, the island was covered with birds, the little trees filled with nests. What the heck was this (aside from an answer to my daily prayers)?

Here only 35 miles from New York City was a colony of cormorants. These are large duck-like birds, which hunt like hawks, nest in trees, can swim and dive like penguins, very strange birds indeed and they don't belong here! Certainly not a loud gregarious colony of them. Moreover they were not about to fly away and leave me cursing.

There was of course one small problem with photographing these guys. After hiking a mile through the woods along the shore of this lake, the closest I could get was 1/5 of a mile from them. This is quite a distance. Now lenses are defined in terms of millimeters. A 50 mm lens has the same perspective as the average human eye. So we can see that a 300 mm, which was the strongest lens I owned, is the equivalent of a 6x magnification, giving me a perspective of about 160 feet. Nowhere near what I needed to make my stunning wildlife photography.

[Photo: Cormorant island at 50 mm]

Cormorant island as the human eye would see it. 50 mm lens.


I ran out and purchased a Sigma 50 - 500 mm lens. Sigma is known as a maker of decent lenses. It makes lenses to match the mounts of its own cameras, but more importantly it makes mounts to match the larger well-known camera manufacturers such as Canon, Minolta and my own Nikon camera. This particular lens has been given rave reviews and costs $800. Truly expensive, but also a third of the price of the equivalent Nikon. It's an amazing lens because of its ability to zoom from a normal perspective to a 10x magnification. It's also very heavy...

As soon as I got this lens I went to once again photograph my cormorants. Still too far away. At 10x the cormorants still looked to be 100 feet off. A distance that I had hoped would be close enough, so that a crop would allow me to see the individual birds clearly. Such was not the case. I did notice the island appeared very close to the opposite shore. So, equipment in hand, I hiked five miles around the lake only to learn a painful lesson. When looking through a telephoto lens there is a phenomenon called foreshortening. It turns out that the island is 1/4 of a mile from the opposite shore! Actually much further away than where I was originally shooting from. By this time autumn had arrived and the cormorants went wherever cormorants go when winter arrives. These are not stupid birds.

This spring I was determined to photograph my only sitting target wildlife, no matter what the cost. Turning to Nikon I priced some of the more exotic lenses. Nikon in fact does make a lens which would probably be adequate. This is a 1,900 mm lens which would bring my birds to about 30 feet. I hoped I could live with that. The small matter of price then came up. This particular lens is a bit pricey, well, actually $70,000. Should I dip into my petty cash fund? Turns out that I was a bit short on funds. The weight of the lens is also a factor. This little baby is 4 feet long and weighs about 70 pounds. Could I hike through the woods with it? An academic question at best because of the cost.

The thought occurred to me that maybe a telescope could be used. I knew nothing about telescopes except that they could, in some way, be hooked to a camera. Credit card in hand I went to my beloved camera store and looked through the 'scope department. These were pretty big objects. Nonetheless I chose one, that although 4 feet long, did not weigh more than 20 pounds. Best of all it came with its own tripod. It cost a mere $400 and so I purchased it.

When arriving home I happily assembled the 'scope and found to my surprise that it could not be mounted without also mounting the celestial motor. This brought the weight up to 70 pounds. Could I hike through the woods with such an instrument? "Piece of cake," I said to myself, easily lifting the assembled machine. As an experiment I hiked around my apartment three or four times before collapsing into the nearest sofa. This also was not going to work.

It was time to do some research
Telescopes, especially the large and relatively cheap ones sold to consumers, turn out to have lousy optics. They work fine for shooting pictures of the moon and stars but good optics are expensive. The problems with these 'scopes are things like chromatic aberrations, where the colors are often incorrect. Then there is lens flare, where spots of light are distorted and magnified. These problems are not that important when you're shooting the black, black sky, with only one object in your viewfinder, but in shooting the real world, your image may be in trouble even if you can lug these 'scopes to the target. More expensive 'scopes, in the over $10,000 range are also way too big for even someone like myself to consider carrying around.

Then there's another category of 'scope. This is the "spotting telescope." Relatively low power, lightweight, and therefore portable. The problems of chromatic aberration and lens flare are solved in two ways:

  1. Use a mirror to magnify the images. These 'scopes, and the Meade series are the best of this group, are quite portable and lightweight, but don't even think of handling them roughly. They can't take the abuse, are quite delicate and are really designed to be used by someone spying on their neighbors from the safety of their apartment (this is academic to me since I live in a basement apartment).
  2. If you spend a lot of money, the kindly manufacturer actually delivers a 'scope, using only glass, without the associated problems of chromatic aberration and lens flare. This is the route that I went. The optics are of a tremendous quality, actually superior to that of a camera lens.

There is, however, another problem with all these 'scopes and that is light gathering ability. A camera, even a digital camera, needs light to record its images. The greater the magnification the greater the amount of light needed because you are concentrating on a very small spot very far away. These spotting 'scopes are, in addition to the rating of magnification, also rated in terms of F-stop, the amount of light that can be gathered, equivalent to a camera lens, that these gadgets are capable of.

[Photo: Chato chasing swans]

Confrontation between the heads of the land and water food chains respectively.


In real terms the amount of light you need is a combination of the size of the aperture (F-stop) and the shutter speed of the camera. So the smaller the aperture, the slower the shutter speed must be in order to capture the same amount of light. Lenses of course allow you to adjust the size of the aperture, while telescopes do not. You get what you pay for. I should point out that in rating F-stops, the smaller the number the larger the amount of light. Large aperture lenses are referred to as fast, because they allow a higher shutter speed to get the same amount of light.

Finally, using such high powered gadgets absolutely requires the use of a tripod. Even the smallest vibration when shooting from huge distances will result in a blurry photo. Don't even think about getting away with using a spotting 'scope (or any other kind for that matter) without a good tripod.

Spotting 'scopes that can be hooked up to a camera, come in a wide variety of price range and quality. After asking around I determined that the best were made by Zeiss and Swarovski. These two brands are waterproof, nitrogen-filled and the optics are beyond belief. Both run about $1,400 with the appropriate adapters. Now this is the point where the question of digiscoping becomes relevant. Take the Swarovski, which is the 'scope I actually bought. It comes, in my case, with a zoom eyepiece rated at 20 - 60x. This eyepiece cannot be hooked up to a conventional SLR or DSLR camera (Single Lens Reflex, with the "D" standing for digital). Theoretically you can, by using reducing rings (little threaded adapters to reduce the size of your lens to match a filter) screw directly onto the eyepiece. But all but the smallest camera lenses are too large to make this practical. The cheaper digital cameras can, with their much smaller lenses, allow the direct connection of the camera to the eyepiece of the 'scope. In effect, you can then use the machinery of the camera to meter and adjust the resulting picture. Thus someone with one of these cameras would have, at highest magnification, a 20 to 60x zoom lens! A word of caution. I do possess a very nice and cheap digital camera, but it has no threads on the lens at all and therefore cannot be used for digiscoping.

In my case I had to purchase Swarovski's separately sold camera adapters, which replace the 'scope eyepiece with the adapter. These are 800 mm and 1,100 mm respectively. In addition I also had to purchase something called a "T-Mount." This at least was cheap. It's a little plastic or metal adapter that is a "camera mount." You take off your lens, substitute the T-mount and then screw your telescope adapter onto the T-Mount adapter, and then lock the whole mess onto the 'scope. Aside from the T-mount, I purchased both eyepiece adapters that Swarovski sells because I intend to use this assembly for more than just shooting cormorants. Since there is no zoom, the 1,100 mm will sometimes be too powerful. At any rate the bottom line here is that I now had a 16 and 22x "lens." This last brought me up to 50 feet from the subjects. Not good enough.

Finally I purchased a teleconverter. This is a gadget that multiplies the magnification of any lens the camera is using. The one I purchased is a 2x teleconverter and I saved money by buying Sigma instead of Nikon. In this case, this was a mistake. A teleconverter, unless of a very high quality, distinctly blurs your image. While Sigma makes high quality lenses, its teleconverters are not up to that standard, so back to the store where I purchased, at a much higher price, a Nikon teleconverter. This now gave me a 2,200 mm lens which in turn brings me to around 25 feet from the target. Hmm?

[Photo: 502 mm]

502 mm.
 
[Photo: 807 mm]
807 mm.
 
[Photo: 1,107 mm]
1,107 mm.
 
[Photo: 2,008 mm]
2,008 mm.


I should pause and say a word about the picture samples. To illustrate this article I shot all the pictures of the cormorants on the same sunny day using
all the adapters and lenses I had. I do not normally lug around all my equipment, but for the benefit of readers, I made that supreme sacrifice. Well, on this island with this sunlight, a lot of detail is lost with glare. None of the images I took hold up when I crop them down. However, on a cloudy day, glare is not a problem. So the two crops of the cormorants' nests were taken on a different day.

[Photo: Crop 1]

[Photo: Crop 2]

Before talking about the software I use, a word or two about spotting 'scopes. As I said, the most expensive ones are made by Swarovski and Zeiss. There are quite a few other brands and no doubt many of them will be capable of doing this kind of work. But words of caution. Years ago I bought the "Halleyscope" for my conventional film SLR camera. I paid $40, the equivalent of $150 today. This 'scope rendered wonderful service as a baseball bat, a club, and from time to time was used to impress children under the age of four. There appear to be some decent 'scopes out there for $400. Check them carefully. If they won't let you put your hands on them, forget about it. The image should be crisp, sharp, with no distortion or aberrations of any kind. Any aberration will be magnified by attaching to a camera. Check its F-stop rating and the equipment needed to connect to a camera. If you want to do long distance photography a good spotting 'scope will match or surpass a good lens. But a lens comes with all sorts of advantages. You can adjust the light gathering ability, they're far less clumsy. Finally - remember, you need a tripod!

[Photo: Dave at the 'scope]

Dave shows he can take a picture of a moving animal. Either a chicken or an immature red tailed hawk with a 500 mm lens.


Now I've successfully become a big time wildlife and nature photographer, the little detail of actually processing these images comes up. I've written about this problem in earlier issues of MyAtari, so you can do a search and find that information. Suffice to say that all digital cameras that use portable memory cards can download, with the aid of a memory card reader, into your Atari. This has to be a SCSI card reader and if you don't have a lot of memory, you will not be able to process these images. They are large. Even with my back-up camera, the resulting images are 6 MB TIFF files. If I shoot in JPEG format, while they may be only 1 MB, to process them you still need the larger amount of memory, because once loaded into an image processing program they decompress to the actual size.

[Screen-shot: DA's Repro]

Speaking of image processing and for that matter actually printing the images, I still use the Atari programs DA's Repro and Calamus SL. DA's Repro has a characteristic found on no other image processing program. This is the ability to make an accurate preview of how your image will actually print on any printer. This is done by taking a sample image to a service bureau and having them print it out. You then go home and using Repro's capabilities, match your screen output to their printed output. The resulting model is then saved and can be recalled at the click of a mouse. In the examples below, I used this method to show how a normal image would print out using the stochastic screening  (Star Screening) option in Calamus SL. If you notice the "before" image is actually how a normal image would print using this option of SL - way, way too dark because the SS option prints out more dots than a normal print method. Using Repro I quickly adjusted the image so that it would Star Screen and give me optimum results. I also have models for various professional printers and for that matter I have options to match the way Photoshop would print these same images on my own printer. Truly a remarkable piece of software, still not matched by anything available on the Mac or PC.

[Photo: Before processing]

How a Star Screened image would print out if not modified in Repro.
 

[Photo: After processing]

How it would print after modification in Repro.


And of course Star Screening itself is only available by using Calamus SL. Now I run both these programs on my Mac as well as my Hades. I also possess Photoshop and Quark Express. I only use Quark for the purpose of being compatible with friends of mine. I compose all my desktop publishing in Calamus SL. Photoshop is a better image processing program than Repro although it lacks the above described capability. I've mastered Photoshop but only occasionally use it since Repro is capable of doing much the same work.

Until next time...

dave@myatari.net

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MyAtari magazine - Feature #3, October 2003

 
Copyright 2003 MyAtari magazine