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Old Apr 4, 2003, 9:41 PM   #1
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Default can I digiscope??

i'm new to photography in general, so i was just wondering, would i be able to attach a scope of some kind to an Olympus E20? if so where do i start? what do i look for?
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Old Apr 6, 2003, 6:04 PM   #2
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Hi,

You "can," but truthfully, I don't think it would be a very satisfactory solution - here's why.

The E20 is very prone to vignetting. Just try to zoom back a little with your TCON-14B attached, or a TCON-300, and you immediately get into vignetting. When you connect the E20 to any telescope, you must do it in an "afocal" manner. That is you will need an adapter to physically hold the objective lens of the E20 in immediate proximity to an eyepiece on the telescope.

To do this with a large objective like you have on the E20, you would need a VERY large eyepiece ocular. Something like the ScopeTronix max 40 would let you use the E20 at full zoom only, and still with significant vignetting. This would work for celestial photos such as the moon, etc., where the blackness of surrounding space obscures and hides the blackness of the vignetting (shadowing around the periphery of the image). But to use if for terrestrial digiscoping (birds, wildlife, etc.) the disadvantage of not having any zoom range make it less than an optimal solution.

My suggestion would be, depending on you budget, buy a Nikon CP4500 or even a used CP950 (extremes in present costs), something like a Celestron or Meade ETX 90 scope (around $175 if you shop around) and a William Optics or ScopeTronix large ocular eyepiece (about $89) which threads directly to the 28mm filter threads on the camera. Then get an Xtend-a-View (about $25) which is a combo sunshade/2x loupe so you can see the LCD with you eye right up to it like a viewfinder. With this relatively inexpensive combination, you can do excellent digiscoping. With your very excellent E20 - it's just not practical because of the large lens and specific configuration. I use an E10 along with many other digicams and truthfully, only my little CP series Nikons (CP4500, 950, 990) are worth a tinker's damn for digiscoping.

Best regards,

Lin
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Old Apr 6, 2003, 10:24 PM   #3
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Lin

Having seen you post two similar writes ups for different posts, it got me thinking. Have you considered putting up a small page describing this poor-man's digitscope setup? I know it's something I'd link up to for future reference.
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Old Apr 6, 2003, 11:56 PM   #4
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Hi Eric,
Actually, I've done that in the past - let me see if I can dig up the images and re-post them.

The Meade ETX-90 - one of my present scopes - has evolved over the years in several configurations. The tube and lens are identical, but the mounting configuration, and specifically the yoke and base, have changed. On the earlier models, there was a battery driven tracking mechanism. One would orient the scope to magnetic north, then when a celestial object were centered, the battery driven motor would "track" the object across the sky. Over the years, this assembly has become more sophisticated and a computerized tracking complete with a "finder" mechanism was developed so that once the set-up was correctly oriented, you could simply call up a star, planet, etc., and the scope would actually "find" it for you. Obviously, the price went up and the retail was around $600. Then Meade discovered that people could also appreciate the ETX-90 as a spotting scope for terrestrial use, and they offered the barrel assembly without the yoke and motorized tracking.

As time went on, the older models began to be heavily discounted. Since all the ETX-90 models always had a tripod mount on the barrel itself, and since there are only four bolts holding the barrel to the yoke and tracking base assembly, buying one of the older, heavily discounted models makes lots of sense. You simply remove the barrel assembly, mount it on your tripod, use Meade's erecting prism which puts things into proper perspective (up is up, left is left, etc.) and mount the camera and you have a dandy little digiscoping system capable of rendering excellent images with one of the little CP series Nikons at up to 6000mm with good lighting.

I'll see if I can round up a photo or two, or make a few new ones and post them.

Best regards,

Lin
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Old Apr 14, 2003, 9:35 AM   #5
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Thanks, I'd appreciate it. I've just been going back through several of your older posts and composing the descriptions of this setup into one file for future use. When I'm on vacation in northern Maine, the osprey and bald eagles just don't let me get within standard camera ranges... no matter how nicely I ask them. I might just save up for a similar system for that trip.

My experience with spotting scopes comes from the high end (AT80-HD) so when I started thinking about doing some digiscoping this is where I looked.. and my eye's bugged out. But what you have described is much more affordable and looks to produce very reasonable pictures.

What would I loose by going the telescope route? I assume lack of APO coatings would increase lens flare. Maybe further minimum focusing distance? Anything else? Just trying to compare to what I know.

And thanks for all your helpful postings (and moderating this part of the forum.) I've learned a lot from all the help/advice you've given here.
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Old Apr 14, 2003, 10:41 AM   #6
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Quote:
What would I loose by going the telescope route? I assume lack of APO coatings would increase lens flare. Maybe further minimum focusing distance? Anything else? Just trying to compare to what I know.
Because the astro-telescopes are mirror types, there is near zero chromatic aberration - at least not any additional beyond that of the camera's own lens system and/or the eyepiece used. Lens flare isn't really an issue either.

Using a small camera like the Nikon CP4500 gets you a couple advantages over the dSLR's like the 10D (from your other post). Though they are used in an afocal manner (shooting through the eyepiece of the telescope), the output is very, very good once you get the hang of focusing with the LCD. To focus with the LCD you really need a little help because sunlight will totally wash out the mediocre comparative brightness. A little inexpensive device called the Xtend-a-View ( www.photosolve.com) which serves as a combination sunshade/2x loupe lets you see exactly what's going on. Certainly it's nowhere near like looking through the lens on a good dSLR like the 10D, but it is good enough to get accurate focus, and the combination of camera and telescope can produce phenomenal results for birding, etc.

Since you have the 10D ordered, you may want to read my post on the eyepiece discussion thread. You definitely can use the Meade with the 10D and get some great shots. The down side is that you are limited to the fixed 2000mm focal length which may or may not be convenient. The up side is that you have lots of resolution for cropping, so unless the bird is so close (usually not the problem) that you can only get a head shot portrait, you can usually crop and still get a decent print.

Swarovski does make two adapters for SLR's, either of which can be used with the ST or AT-80 series. One gives a focal length of about 800mm and the other 1100mm with a 35mm film camera. That translates to 1280mm and 1760mm with the 10D or other 1.6x field of view crop sensors.

Of course the advantage of the Swarovski is that it's waterproof, fog proof and rugged for trail or backpacking use. The Mead is obviously designed as a fairly delicate astro-telescope converted to spotting scope. It's neither waterproof nor fog proof nor of rugged construction, so that you would need to exercise due caution when taking it in the field. A good zipper padded case and some plastic to wrap it should you get into bad weather would be in order. But then the investment is minimal, and even if you do accidentally destroy it the loss would not be monumental.

The Meade ETX-90 or Celestron equivalent, etc., make very useful spotting scopes and can definitely be used with a variety of cameras to get excellent images. Of course, you must remember that when using one of these with your 10D, you must do all focusing with the lens and you will have no electronics informing the camera of aperture, etc., so you are on your own with full manual settings. This means some trial and error is necessary in learning to get the proper ISO and settings for the existing light conditions. With the Nikon and afocal setup, the metering and all electronics, etc., are working because the telescope is just an extension lens. It's just a little bit easier with the afocal setup to get good results with less experimentation.

Best regards,

Lin
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