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Old Apr 14, 2006, 10:05 PM   #1
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Hello,

I am interested in digiscoping and am wondering if I am correct in my understanding that there are three different approaches, configured as follows:

(1) Using a Digital SLR: attaching a scope-specific adapter to the scope (scope eyepiece removed?); connecting a T-adapter specific to the camera and scope; then attaching the camera to the T-adapter. (prime focus)

(2) Using a Digital P & S (without filter threads on its lens): leaving the scope eyepiece in place?; attaching a mechanical mount to the scope; placing the P&S into the mount; then adjusting the mount in order to get the P & S as close as possible to the eyepiece. (afocal 'a')

(3) Using a Digital P & S (with filter threads on its lens [or on its filter adapter if it has one]): leaving the scope eyepiece in place? (the eyepiece in this case must have threads); attaching a mechanical mount to the scope; placing the P&S into the mount; then adjusting the mount in order to be able to connect the P & S to the eyepiece through the filter / eyepiece threads using some type of adapter. (afocal 'b')

Clarification on this would be very useful,

Thanks in advance,

Bjorn.


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Old Apr 15, 2006, 1:12 AM   #2
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odesius wrote:
Quote:
Hello,

I am interested in digiscoping and am wondering if I am correct in my understanding that there are three different approaches, configured as follows:

(1) Using a Digital SLR: attaching a scope-specific adapter to the scope (scope eyepiece removed?); connecting a T-adapter specific to the camera and scope; then attaching the camera to the T-adapter. (prime focus)

(2) Using a Digital P & S (without filter threads on its lens): leaving the scope eyepiece in place?; attaching a mechanical mount to the scope; placing the P&S into the mount; then adjusting the mount in order to get the P & S as close as possible to the eyepiece. (afocal 'a')

(3) Using a Digital P & S (with filter threads on its lens [or on its filter adapter if it has one]): leaving the scope eyepiece in place? (the eyepiece in this case must have threads); attaching a mechanical mount to the scope; placing the P&S into the mount; then adjusting the mount in order to be able to connect the P & S to the eyepiece through the filter / eyepiece threads using some type of adapter. (afocal 'b')

Clarification on this would be very useful,

Thanks in advance,

Bjorn.
Quote:

Hi Bjorn,

That's essentially it with afew variations.It's either use an SLR or dSLR attached to the scope via a "T" mount directly as with mirror type scopes or via specialized lens adapters and a "T" mount with terrestrial spotting scopes. Companies such as Swarovski, Leica, Kowa, etc., make adapters which have optics built in that make these relatively short focal length spotting scope barrels into 800mm-1100mm lenses. The longer the focal length the smaller the aperture range.

With a scope such as the Celestron 90'sor Meade ETX-90, etc., there is no need for additional glass because they generally have a dedicated camera port which connects to the camera end via a standard "T" mount and to the scope via a "T" adapter which screws to the dedicated port.

With fixed lens digicams, especially those with relatively small objective lenses such as the Nikon CP series (CP800, 900, 950, 990, 995,4500, etc.) youcan connect afocal via the eyepiece. Companies such as ScopeTronix and William Optics make dedicated eyepieces which can either directly replacethe existing removable eypiece oneither a celestial reflector or a terrestrial spotting scope or attach via specialized adapters. Most of these eyepieces are 1.25" barrel types and have threads mating to the filter threads on theobjective side of the digicam. The best cameras for digiscoping have limited optical zoom (not over 4x) and are more versatile than an SLR or dSLR because you can zoomsometimes up to 80% of the zoom range of the camera for differential framing.

Cameras which have optics amenable to digiscoping but which don't have filter threads can be mechanically attached via a mechanism which generally attaches to the tripod mount on the camera andclamps around theeyepiece on the telescope. This brings the objectivelens of the camera and the eyepiece into close proximity.

In some respects the digicams out-perform the SLR/dSLR because there is no mechanical shutter to cause vibration and you have the ability to zoom and frame the subject. With a dSLR/SLR you essentially have a "prime" lens situation with fixed focal length and all that entails. Of course the dSLR has better resolution and overall native image quality, the ability to shoot at higher ISO's, etc., but this sometimes isn't as big an advantage as the greater focal length range of the digicam afforded via the optical zoom.

With a dSlR about the best you can hope for is an effective 2000mm (1.6x crop factor plus 1250mm native focal length barrel of a MeadeETX-90, etc.). With small lens 4x optical zoom digicams shooting through the eyepiece it's quite possible to get usable images at up to 6000mmfocal length.

Best regards,

Lin
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Old Apr 15, 2006, 11:10 AM   #3
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Hello Lin,

thanks for the explanation! Very useful.

Two additional questions:

(1) Regarding setup time:
Are any of the three digiscoping approaches at all close to just using a DSLR with a telephoto on a tripod (say 400mm with doubler)? I do a lot of backcountry / international trekking and hiking and want a system that is flexible enough that if I come across interesting wildlife that I can set the system up fairly quickly. The reason digiscoping is so appealing is that it sounds like the very high magnification can allow really long distance wildlife visualization (say a mountain goat or grizzly) without disturbing the creature and / or putting one's self in danger. However, if it takes say 10 minutes each time to set up, it may not be that useful for my trekking purposes.

(2) Regarding 'ruggedness / 'weatherproofness'
As mentioned above, I do a lot of backcountry stuff, including in wet / rainy / tropical conditions as well as cold weather temperatures. Are any of the above three digiscoping and standard camera telephoto setups much better than the others in this regard? Intuitively I would think that the weakpoint is at the adapter-level (i.e. where the camera interfaces with the scope) since one can get both weather-proof scopes and cameras. Is the best option to just get a cover (e.g., the EWA 'raincoats') to cover the entire setup or is there a different solution?

Thanks in advance,

Bjorn.
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Old Apr 15, 2006, 2:10 PM   #4
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odesius wrote:
Quote:
Hello Lin,

thanks for the explanation! Very useful.

Two additional questions:

(1) Regarding setup time:
Are any of the three digiscoping approaches at all close to just using a DSLR with a telephoto on a tripod (say 400mm with doubler)? I do a lot of backcountry / international trekking and hiking and want a system that is flexible enough that if I come across interesting wildlife that I can set the system up fairly quickly. The reason digiscoping is so appealing is that it sounds like the very high magnification can allow really long distance wildlife visualization (say a mountain goat or grizzly) without disturbing the creature and / or putting one's self in danger. However, if it takes say 10 minutes each time to set up, it may not be that useful for my trekking purposes.

(2) Regarding 'ruggedness / 'weatherproofness'
As mentioned above, I do a lot of backcountry stuff, including in wet / rainy / tropical conditions as well as cold weather temperatures. Are any of the above three digiscoping and standard camera telephoto setups much better than the others in this regard? Intuitively I would think that the weakpoint is at the adapter-level (i.e. where the camera interfaces with the scope) since one can get both weather-proof scopes and cameras. Is the best option to just get a cover (e.g., the EWA 'raincoats') to cover the entire setup or is there a different solution?

Thanks in advance,

Bjorn.
Hi Bjorn,

dSLR:
Actually no. Though you "can" set up the Swarovski or Leica digiscoping solution very quickly, it's not equal to a decent 400mm with a 2x teleconverter because you loose all the electronics and are left with complete manual focus, pretty much "guessing" at which ISO will give you the right exposure and because of the much longer focal length you need a rock steady tripod, mirror lockup (which means you loose sight of the subject) and such. To get away with a lighter carbon fiber tripod suitable for back-packing you would need to fill a sack with rocks and hang it from the center to get the additional stability - something digiscopers do on a regular basis but not something which can be quickly accomplished.

Digiscoping is really "best" when you can set up everything and shoot from a normal distance rather than for getting "long-range" shots. It's value is in making extreme closeup's of relatively close-in subjects such as filling the frame with a tiny bird or a head & shoulders "portrait" of a larger bird. The further you are from the subject the more the environment plays against you. Heat waves rising, atmospheric conditions causing issues, etc. It's really a way of getting extreme closeups of subjects in range for normal photography rather than what we all would love to do - bring those really distant subjects into range.

Fixed Lens Solutions:
It's about the same only magnified. Since the focal lengths become extreme with afocal shooting, all the issues with the dSLR in digiscoping are simply made more critical. Even tiny amounts of vibration from the wind or earth movement from passing vehicles (assuming you are not in the deep forest) become the enemy. This type digiscoping can bring wonderful results but the number of "misses" are much greater than the number of "hits" so that set-up is very critical and much more care must be taken. Definitely this is not a very satisfactory solution for the backpacker or hiker.

I would say that for your intended purposes, a decent 400mm or even a stabilized zoom lens with a teleconverter would be a much more useful solution.

Best regards,

Lin
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Old Apr 15, 2006, 4:00 PM   #5
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Thanks Lin!

This type of information can save a newcomer to this field a lot of time.

Best regards,


Bjorn.
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