Hi. After watching butterflies in my garden and at a few local sites in Cambs, I have become interested in solving an unsolved problem. I have used a small number of optical instruments (binoculars and modified spotting scopes) in order to follow the butterflies and look at them at close focus. It appears that no-one has ever properly designed a dedicated butterfly (and other insect) scope. A close focus binocular or monocular is fine but (as optics is my field) I know that a power of 8X or 10X is OK some of the time, but the appearence of a butterfly is transformed at powers of 20X and over, with a stationary instrument that is corrected for close focus spherical aberration. So, I intend to design the ideal butterfly-watching scope. It will have a magnification range of 10X to 30X (or more if required), a close focus down to 1m and with a flat field, apochromatic, and a very low level of spherical aberration at close focus. I can also make use of visual polarizer filters as part of this instrument, as this help to see colours better and reduce reflected light.
What I need from you guys is a little help from experienced field observers.
e.g. What is it you would like the perfect butterfly scope to be able to do. What are the pitfalls of using conventional instruments for watching butterflies (i.e. modern birdwatching optics). Is waterproofing required, i.e. exactly what proportion of insect observing is carried out when it is raining or extremely humid? How many UK butterfly enthusiasts travel to tropical and sub-tropical environments in order to see more exotic species? (this plays a part in whether or not waterproofing is important). Just what level of detail would you like to see on a butterfly.
Other aspects of butterfly watching that need to be taken into account when designing a dedicated instrument.
If you don't have the answers I need, perhaps you can put me in touch with a group, or individuals who can provide the answers I need.
Many thanks for your co-operation.
Best wishes
Rubystar
Dedicated butterfly scope.
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Cotswold Cockney
- Posts: 487
- Joined: Sun Dec 31, 2006 9:39 pm
- Location: GLOUCESTERSHIRE
For nearly 40 years, I have used a pair of Zeiss (West) 10 x 50 Binoculars. They are ideal for all my various interests including identifying things high in the trees.
Something with a magnification of up to x30 would be impossible to hand hold effectively and many subjects would be gone by the time the tripod and focus have been set up..... Even so, I'd be interested if you have in mind optics with image stabilising as that may overcome the problems associated with large magnifications.
Good luck with your project.
Something with a magnification of up to x30 would be impossible to hand hold effectively and many subjects would be gone by the time the tripod and focus have been set up..... Even so, I'd be interested if you have in mind optics with image stabilising as that may overcome the problems associated with large magnifications.
Good luck with your project.
Cotswold Cockney is the name
All aspects of Natural History is my game.
All aspects of Natural History is my game.
Dedicated butterfly scope.
Thanks for your input (Cotswold Cockney). I too use 10X binoculars and much of the time this is fine for following butterflies around or for identifying them whilst on the move (although I find it difficult if not impossible to identify the fast flyers unless they land).
I modified my Kowa spotting scope to use it at close focus (approx. 3m). The downside to adapting a conventional spotting scope is that the focus distances become rather restrictive. e.g. With my adapted Kowa used with an 18mm eyepiece, the power is 23.3X. However, the closest focus is about 3m, but the focus travel restriction on conventional spotting scopes means that the furthest I can focus is about 10m. In order to focus on something further I have to remove the close focus adapter and place the normal Kowa eyepiece in, then I can focus to infinity but close focus is then restricted.
The upside is that if I add a Barlow lens (increases the power like a teleconverter on a camera) directly onto the bottom of the eyepiece I get 35X. Between these two magnifications (23.3X and 35X) I can see exquisite detail on butterflies that are between 3m and 10m distance. Adding a circular polarizer reduces light reflection from leaves and helps to see colour and detail even better. The butterflies take on a whole new form at higher powers with higher quality optics. You can actually count the individual fur cilia and watch quite clearly the pollen collecting on the insect and every detail of the feeding structure. Some of the wing detail on species like Black Hairstreak, Small Coppers, Ringlets, Speckled Woods, White Admirals etc is quite breathtaking. Even with the benefits that a close focus high power scope can offer there are still improvements that I can make. For example, all spotting scopes suffer increasing amounts of spherical aberration as you focus closer. This means that image sharpness and contrast is lost the closer you get to close focus with each particular instrument. I can design a scope that won't lose the image quality at close focus. The image quality can be better than 'in hand', because of the extra resolution of a scope over the naked eye.
I have found on preliminary field tests that a scope is difficult to use unless it is tripod mounted. This is taken as given. Further, that a tripod-mounted scope is still difficult to use for following a butterfly around, simply because of depth of field, speed of the butterfly in context with higher magnification plus individual hand/eye coordination.
What I think I can offer is this -
A scope of lightweight build and compact size, with apochromatic image quality, as flat-field a design as possible (good image quality toward the edge of the field of view), a close focus of approx. 1m, no or minimal spherical aberration at close focus (means superior image quality at close focus to any spotting scope or monocular on the market), a magnification range of between 10X (or 8X if enough people scream for it) and 30X (or more if enough people scream for it), the ability to change power without changing eyepiece (a time consuming thing), without having to use a zoom system, ( as ALL zoom systems are flawed), and an in-built polarizer that can be 'tuned' on or off as required.
I appreciate that even more that birdwatching optics, optics for butterfly watching need to be extremely user-friendly because of the nature of flying insects, however I think this can be comfortably taken into account.
What I need is more input about aspects of watching insect and butterflies that I have not considered. In this way the design of the scope will adapt to take these aspects into consideration.
Keep it coming - more experiences using conventional 'off the shelf' optics and your thoughts regarding your dream instrument for butterfly watching. Don't forget, only 3 decades ago the vast majority of birdwatchers didn't use telescopes, only binoculars. I have a feeling that a dedicated high quality scope for butterfly watching will open up a new dimension of enjoyment for observers.
Best regards
Rubystar
I modified my Kowa spotting scope to use it at close focus (approx. 3m). The downside to adapting a conventional spotting scope is that the focus distances become rather restrictive. e.g. With my adapted Kowa used with an 18mm eyepiece, the power is 23.3X. However, the closest focus is about 3m, but the focus travel restriction on conventional spotting scopes means that the furthest I can focus is about 10m. In order to focus on something further I have to remove the close focus adapter and place the normal Kowa eyepiece in, then I can focus to infinity but close focus is then restricted.
The upside is that if I add a Barlow lens (increases the power like a teleconverter on a camera) directly onto the bottom of the eyepiece I get 35X. Between these two magnifications (23.3X and 35X) I can see exquisite detail on butterflies that are between 3m and 10m distance. Adding a circular polarizer reduces light reflection from leaves and helps to see colour and detail even better. The butterflies take on a whole new form at higher powers with higher quality optics. You can actually count the individual fur cilia and watch quite clearly the pollen collecting on the insect and every detail of the feeding structure. Some of the wing detail on species like Black Hairstreak, Small Coppers, Ringlets, Speckled Woods, White Admirals etc is quite breathtaking. Even with the benefits that a close focus high power scope can offer there are still improvements that I can make. For example, all spotting scopes suffer increasing amounts of spherical aberration as you focus closer. This means that image sharpness and contrast is lost the closer you get to close focus with each particular instrument. I can design a scope that won't lose the image quality at close focus. The image quality can be better than 'in hand', because of the extra resolution of a scope over the naked eye.
I have found on preliminary field tests that a scope is difficult to use unless it is tripod mounted. This is taken as given. Further, that a tripod-mounted scope is still difficult to use for following a butterfly around, simply because of depth of field, speed of the butterfly in context with higher magnification plus individual hand/eye coordination.
What I think I can offer is this -
A scope of lightweight build and compact size, with apochromatic image quality, as flat-field a design as possible (good image quality toward the edge of the field of view), a close focus of approx. 1m, no or minimal spherical aberration at close focus (means superior image quality at close focus to any spotting scope or monocular on the market), a magnification range of between 10X (or 8X if enough people scream for it) and 30X (or more if enough people scream for it), the ability to change power without changing eyepiece (a time consuming thing), without having to use a zoom system, ( as ALL zoom systems are flawed), and an in-built polarizer that can be 'tuned' on or off as required.
I appreciate that even more that birdwatching optics, optics for butterfly watching need to be extremely user-friendly because of the nature of flying insects, however I think this can be comfortably taken into account.
What I need is more input about aspects of watching insect and butterflies that I have not considered. In this way the design of the scope will adapt to take these aspects into consideration.
Keep it coming - more experiences using conventional 'off the shelf' optics and your thoughts regarding your dream instrument for butterfly watching. Don't forget, only 3 decades ago the vast majority of birdwatchers didn't use telescopes, only binoculars. I have a feeling that a dedicated high quality scope for butterfly watching will open up a new dimension of enjoyment for observers.
Best regards
Rubystar
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Rogerdodge
- Posts: 1177
- Joined: Tue Jan 31, 2006 6:06 pm
- Location: North Devon
I can't really see what you are trying to acheive?
If we take it as read that it is not feasible to hand-hold anything above 10x, and using a tripod for buterfly viewing is not really practical, what are you trying to get that you can't get from a good pair of 10x32 binoculars?
Canon do IS binoculars, but they are heavy, expensive, and make you travel sick after a while!
Roger Harding
If we take it as read that it is not feasible to hand-hold anything above 10x, and using a tripod for buterfly viewing is not really practical, what are you trying to get that you can't get from a good pair of 10x32 binoculars?
Canon do IS binoculars, but they are heavy, expensive, and make you travel sick after a while!
Roger Harding
Roger.
You are right, it is not easy or worthwhile to handhold much more than 10X, however, after much investigation I would argue that a stable 'still' image is essential if clear detail is to be had, and therefore tripod mounting is the only economical way. I don't have a problem with finding and focussing at 35X on a butterfly at 3m distance with a tripod mounted telescope, although the butterfly has to be settled. I have tried several different magnifications and it occurs to me that for those interested in really inspecting a butterfly in very fine detail, then a higher power is needed, plus higher quality optics at close focus than is currently available. This all requires a tripod, because, as you say, giro stabilised instruments are very expensive, and I have yet to see one that I would regard as having a high quality image, particularly at close focus.
The magic is in the sheer breathtaking clarity and visible detail in the butterfly with the instrument I have in mind. It is of course not for everyone, many will not need more than a good pair of binoculars for simple identification, but unless you have experienced a high power image of a butterfly with well corrected optics, it is difficult to express excactly what is to be gained.
The same was true in birdwatching a couple of decades ago. Binoculars are ideal for finding, following and initial identification of a bird. For clear detail observation and for experiencing the 'magic' in a sharp high contrast magnified image of the bird, the telescope is required. No modern birder these days travels to a twitch or a reserve without a scope. It takes many years for an idea to soak down through an entire consumer market, hence the time taken for birders to recognise a scope as an essential piece of kit. I would argue the same is true for butterfly observing. A low power wide-field binocular for finding and identification, and a dedicated scope for identification at greater distances or close detail inspection.
I am going to design one anyway, but really need from you guys accounts of when your optics are useful or not, and what about them you wish were improved, (in terms of field use).
As an aside, it is worth noting that ALL off-the-shelf binoculars (regardless of make) suffer from close focus spherical aberration with varying degrees depending on model and design. Simply making binoculars that focus closer and closer (as has happened over the last 10 years or so) does not address the issue of aberrations at close focus. Butterfly observers and those that observe insects have a specific requirement that birders do not have, hence the need for a purpose designed instrument.
Best regards
Rubystar
You are right, it is not easy or worthwhile to handhold much more than 10X, however, after much investigation I would argue that a stable 'still' image is essential if clear detail is to be had, and therefore tripod mounting is the only economical way. I don't have a problem with finding and focussing at 35X on a butterfly at 3m distance with a tripod mounted telescope, although the butterfly has to be settled. I have tried several different magnifications and it occurs to me that for those interested in really inspecting a butterfly in very fine detail, then a higher power is needed, plus higher quality optics at close focus than is currently available. This all requires a tripod, because, as you say, giro stabilised instruments are very expensive, and I have yet to see one that I would regard as having a high quality image, particularly at close focus.
The magic is in the sheer breathtaking clarity and visible detail in the butterfly with the instrument I have in mind. It is of course not for everyone, many will not need more than a good pair of binoculars for simple identification, but unless you have experienced a high power image of a butterfly with well corrected optics, it is difficult to express excactly what is to be gained.
The same was true in birdwatching a couple of decades ago. Binoculars are ideal for finding, following and initial identification of a bird. For clear detail observation and for experiencing the 'magic' in a sharp high contrast magnified image of the bird, the telescope is required. No modern birder these days travels to a twitch or a reserve without a scope. It takes many years for an idea to soak down through an entire consumer market, hence the time taken for birders to recognise a scope as an essential piece of kit. I would argue the same is true for butterfly observing. A low power wide-field binocular for finding and identification, and a dedicated scope for identification at greater distances or close detail inspection.
I am going to design one anyway, but really need from you guys accounts of when your optics are useful or not, and what about them you wish were improved, (in terms of field use).
As an aside, it is worth noting that ALL off-the-shelf binoculars (regardless of make) suffer from close focus spherical aberration with varying degrees depending on model and design. Simply making binoculars that focus closer and closer (as has happened over the last 10 years or so) does not address the issue of aberrations at close focus. Butterfly observers and those that observe insects have a specific requirement that birders do not have, hence the need for a purpose designed instrument.
Best regards
Rubystar