Compass and Reticule Binoculars for vantage point surveys (1 Viewer)

[u10ajf]

Hi Folks,
My name is Andy Francis, I do surveys for environmental impact assessment for wind farms. Part of the job requires plotting flight lines of birds on maps and estimating their heights at 15 second intervals. In essence this is very simple but when you think about it it's actually 3D trigonometry (which has also been said about catching a ball but its easier to know if you miss the catch!). For some reason, and in spite of the growing wind-farm development market, there is no information about methods and equipment for the purpose. I am trying to research the use of compass binoculars with reticule rangefinders (the ones with lines on which you use to measure the apparent angle subtended by an object) because laser rangefinders struggle to aquire targets at distances and are expensive. The main caveat in this method is that most compass binoculars lack inclinometers. Apart from laser rangefinding types the only model I've found with one is a 7x50 model with electronic compass that is made by Bushnell. I wondered if anyone has any experience of compass binoculars with reticules. I am hoping to engage as many bird workers as I can in discussing this matter and the methods they use to train themselves because this area of knowledge seems so un-discussed that there is practically no information on the internet and optics manufacturers don't generally seem to be making equipment for this purpose. I have attached a document for appraisal and feedback.

 

[Binastro]

I'm certainly no expert at this but cheap marine compass binoculars jam as soon as you tilt the binocular a little bit up and the compass directions are incorrect.

Better ones from Nikon and Steiner do better but I don't think any of the normal compass binoculars can be tilted very far.

The military reticule binoculars measure normally in millirads but I don't know how good they are for your work.

Anyway I have not yet read your posted item fully.

I just thought I'd point out that normal Marine compass binoculars might not be suitable for your work.

I have used digital inclinometers a little bit for astronomy.

 

[u10ajf]

Wow, that was fast! Thanks for replying! I know what you mean about compasses getting stuck. I was wondering about digital compasses and if they can cope with higher elevations. Where the Steiner and Nikon ones you were suggesting digital or 'traditional' in design? I see no reason why in principle a mechanical false horizon (part compass part inclinometer) should not be produceable but I suspect digital designs are more likely to have inclinometers than traditional compass designs. Pragmatically very high elevations (bove 60 degrees) are rare and typically from birds that are passing more or less straight over so compass jamming probably wouldn't matter so much. I have a little Celestron Oceana monocular, it was quite cheap and exceeded my expectations vastly (it's brilliant for navigating and, for the price, surprisingly decent optically) but it jams at an angle of perhaps only +- 30 degrees. I have found that it gives very consisent readings of angles (from one day to another) which I'm very pleased about but I miss using both eyes which is why I'm trying to find out about suitable binoculars!

 

[typo]

Perhaps I haven't quite understood the nature of the problem, but my initial impression is that it might be task best solved by an imaging system. Many cameras, and indeed phones have GPS systems readouts and time stamping. The scaling can be derived by the known magnification or focal length. Add in a bit of image analysis and you should be able to track birds in a three dimensional space. There are free image analysis packages like ImageJ that should get you quite far. It can be done off a video rather than stills but that needs a bit more know-how on the number crunching.

I'm probably being a little naive.

David

 

[dalat]

Hi Andy,

did you ever try to use surveying equipment? I guess with a total station you should easly be able to record horizontal and vertical angles by pressing a button. Difficulty would probably remain the distance measurement, the total stations laser distance measurement is probably better than those of binocular rangefinders, but if it works on flying birds? Btw. I don't think the laser in rangefinders is any dangerous to birds and humans.

The best method is probably radar, but I guess there you come into different dimensions regarding price. I don't know how established this technology is already, but in Switzerland there has been a lot of work on this. Recently I saw a presentation and was quite impressed what radar can do, they even manage to automatically ID birds, bats, etc based on wing beat frequency...
http://www.vogelwarte.ch/radar-ornithology-project.html
http://www.swiss-birdradar.com/birdscanmv1.html

Best, Florian

 

[iveljay]

The new Minox Nautic range may be along the lines you are thinking about. The top of the range models have digital compasses, digital inclanometer etc.

To quote:

'A revolutionary and unique feature is the digital multi-function display that appears in the center of the field of view at the press of a button. Whereas conventional navigation binoculars work with analog compass technology, the innovative BN 7x50 DCM has a fully integrated digital compass, enabling the skipper to keep his eye on an object without losing sight of the compass reading.

The multi-function display provides a lot more useful information besides, including temperature and temperature history, tilt angle, altitude, clock and stopwatch. The digital barometer function shows the current air pressure and air pressure history over the last eight hours.

These Nautik binoculars are also equipped with a highly sensitive gravity sensor that allows for automatic tilt compensation.'

I must admit that I find digital compasses excellent as long as you remember to recalibrate (usually trivial) every now and again at least you dont get sticking compass cards.

http://www.minox-optik.de/nautik/en/products/bn-7x50-dcm/features

The manual with accuracy estimates can be downloaded from here http://www.minox-optik.de/nautik/en/downloads/func-startdown/15/

The main downside is that they don't float apparently and of course don't have central focussing.

 

[Binastro]

. For astronomy the inclinometer I use that cost about £14 is very accurate but I understand in certain situations the accuracy is very compromised.

I do have an amazing MINOX binocular that has an altimeter and barometer that is accurate to 0.1 mbar in other words to less than 3 feet. It was sold at below one third of the normal price because nobody wanted them.

The problem is I have no way of calibrating it because you would need to go to a physics lab or somewhere similar to get an accurate barometer fix.

I wonder if the new Sony DEV second-generation digital binoculars can do the job.
They are expensive.

 

[u10ajf]

Thanks very much for your ideas everyone! Im kind of tired so I haven't done
all the reading and looking I'd like to yet to but, in the interim I can say:

Hi David !(typo) - I like your thinking! This stuff sounds good and geeky, I wish I had the
know how to take it on. I see that the software you mention is able to measure
areas and angles - well that certainly is useful. I like the idea of shots,
slowing things down would be bound to increase accuracy. It sounds a bit gadget
intensive and whether it ever gets implemented is a function partly on how
seriously consultancies take the issue. As yet they seem alright with plodding
along expecting new recruits to have miraculous super-powers and if not to figure
it all out for themselves. I'm not sure how many would want to throw enough
time and money at the problem. Some time when I have more time I will take a look
at ImageJ - I love free GNU type software (it's a kind of geek idealism that
developers make open source programs available to improve peoples lives and not
even expect money for it). Cheers!

Hi Florian (Dalat) - I hadn't considered surveying equipment per see although I was aware that
a lot of the principles are similar. I would be very surprised if the ranging
of small objects is possible but will look into it. As for Radar, I'm aware radars are
being used but have not put in the time to study their implementation, fascinating
as it sounds. I am aware that there is a caveat that radars are not able to
distinguish between species of birds but that does not mean that they can not
be used in conjuction with a human observer. When that happens (and happens cheaply enough)
I'm out of a job but at least I'll get to watch birds for fun instread ! I'll have
aread of those links when I'm not so tired.

Iveljay - thanks for suggesting another model to find out about - will definitely
look at the manual in more detail. For now I can say that it's interesting
that it also has a stop watch but I think the tilt function just means the
compass works even when tilted rather than that this model has an inclinometer.
If I'm right about this then probably the Bushnesll 7x50 with digital compass and
inclinometer is slightly ahead on points still. I'll read this again when I'm
more awake!

Binastro - thanks again! I don't know about the Sony DEV - have added this to
my things to read list!

Thanks everyone and keep the ideas coming if you think of any more solutions
or products!
Cneers, Andy

 

[Ruff]

Perhaps 15 years ago I was given a pair of mint-looking Steiner Commanders, so for me they were second hand. I was intending to use them recreationally for taking quick navigational bearings and so on. Everyone who looked at them was extremely impressed and the optics were pretty go also. Second or third time on a small boat but on the first opportunity actually, they got wet, filled with water and moulded out. In other words they were trash for the intended purpose. End of story except for the tears. EDIT: Steiner in Canada offered to sell me a new pair for about $350 but I didn't think they were worth even that.

 

[dalat]

When that happens (and happens cheaply enough) I'm out of a job but at least I'll get to watch birds for fun instread !

Well, complicated tools also need someone who knows how to use them, process and analyse data, produce nice graphs and put them in a report. I guess consultants can sell this much better than endless work-hours involving nothing more than the use of a binocular

 

[chris butterworth]

When I was part of the Liverpool Bay Common Scoter survey I took a series of photographs before hand from the static position I would be using, and printed them off as A4 sheets. Knowing the site, and having a good idea of how far out the birds were made it easy to add hight (just draw a line on your photo corresponding to the view you have of the birds), direction ( compass bearing ) and number directly onto the paper then do the calculations / analysis at home. It was a bit cumbersome to start but, within an hour or so, it became almost instinctive. A lot cheaper than buying expensive equipment.

Chris

 

[u10ajf]

Hi Chris! I'm really pleased that approach worked for you and have been thinking along fairly similar lines. I recently took a series of panoramic photos of my vantage points. I decided to make line drawings of them as I was also thinking of printing them out but wanted to save print costs. In my case I felt that a stripped down version of a panorama would be an uncluttered aid to the memory helping observers to get the main land marks rather than the haze of anonymous trees and tufts of grass - a kind of focus on the real land marks. In the end I realised I had some video making software with MS (Windows live Movie Maker) that had an "edge detect" function so I used it to take some of the detail away although I had to take screenshots and paste them into paint. I intend to add an eyeline (points of land of equivalent altitude) and some compass bearings but it's a big job as I have 15 vantage points. I hadn't thought of marking the bird flights on directly and working it out later and had merely been thinking of a way of familiarising myself with my eyeline and perhaps a sense of elevation angles and bearings. Maybe drawing the flight line is a good way forward.. I think having a good idea how far out the birds are would likely have been a big help too - birds I see (and there aren't so many) aren't so well behaved unfortunately!
Your approach reminds me a bit of the Whale and Dolphin conservation society approach used by their shorewatch program - they take bearings and measure how many graticules below the horizon (or where the sea and land meet) the whales or dolphins are. Someone else then does the analysis from the data later.
Thanks for your suggestion!

When I was part of the Liverpool Bay Common Scoter survey I took a series of photographs before hand from the static position I would be using, and printed them off as A4 sheets. Knowing the site, and having a good idea of how far out the birds were made it easy to add hight (just draw a line on your photo corresponding to the view you have of the birds), direction ( compass bearing ) and number directly onto the paper then do the calculations / analysis at home. It was a bit cumbersome to start but, within an hour or so, it became almost instinctive. A lot cheaper than buying expensive equipment.

Chris

 

[u10ajf]

That's terrible - was your benefactor able to get their money back for your water logged present? I thought marine binoculars were genuinely waterproof.

Perhaps 15 years ago I was given a pair of mint-looking Steiner Commanders, so for me they were second hand. I was intending to use them recreationally for taking quick navigational bearings and so on. Everyone who looked at them was extremely impressed and the optics were pretty go also. Second or third time on a small boat but on the first opportunity actually, they got wet, filled with water and moulded out. In other words they were trash for the intended purpose. End of story except for the tears. EDIT: Steiner in Canada offered to sell me a new pair for about $350 but I didn't think they were worth even that.

 

[Ruff]

That's terrible - was your benefactor able to get their money back for your water logged present? I thought marine binoculars were genuinely waterproof.

It was my father in law and his health was really bad, didn't trouble him about it. I can't say the maker didn't try to make it right, as I described, but it seemed like throwing good money down the sewer. The rep said it was a common problem with that model year!

 

[james holdsworth]

Andrew,

I [and others in my team] have been doing bird surveys of Wind turbines since 2004 and part of the survey methodology involves trying to estimate height to plot on mapping to illustrate primary flight lines and altitude [as compared to the turbine] of large, diurnal migrants - mostly raptors, waterfowl, loons and shorebirds.

We were never really required to come up with any ''exact'' figure and all we did was use known point on the tower base and blade to estimate height. For example - just above top of blade = 120 + meters, mid-tower = 60 meters, below blade sweep = 20 and less. With no turbines present, use known landmarks nearby to compare height.

After awhile, you develop a pretty good eye for this and can quickly map passing birds.

Most of these observations are guesstimates but, in the end, what we wanted to compile was a general illustration of where the bulk of the birds were flying as they passed the turbine. Not perfect but it still produces a good idea of which species are problematic and those that are really not at all affected.

 

[brocknroller]

Hi Folks,
My name is Andy Francis, I do surveys for environmental impact assessment for wind farms. Part of the job requires plotting flight lines of birds on maps and estimating their heights at 15 second intervals. In essence this is very simple but when you think about it it's actually 3D trigonometry (which has also been said about catching a ball but its easier to know if you miss the catch!). For some reason, and in spite of the growing wind-farm development market, there is no information about methods and equipment for the purpose. I am trying to research the use of compass binoculars with reticule rangefinders (the ones with lines on which you use to measure the apparent angle subtended by an object) because laser rangefinders struggle to aquire targets at distances and are expensive. The main caveat in this method is that most compass binoculars lack inclinometers. Apart from laser rangefinding types the only model I've found with one is a 7x50 model with electronic compass that is made by Bushnell. I wondered if anyone has any experience of compass binoculars with reticules. I am hoping to engage as many bird workers as I can in discussing this matter and the methods they use to train themselves because this area of knowledge seems so un-discussed that there is practically no information on the internet and optics manufacturers don't generally seem to be making equipment for this purpose. I have attached a document for appraisal and feedback.

Andy,

If this purchase isn't coming out of your own pocket, check out the new Leica Geovid. It's meant for hunting and can track ballistic paths uphill, but it might be adaptable to your purpose.

http://us.leica-camera.com/sport_optics/rangemaster_new/Geovid_new/

Brock

 

[Hans Weigum]

http://www.vectronix.ch/#/en/products/handheld_equipment/rangefinders/vector_rangefinder_binoculars

If costs don't matter.

 

[Ruff]

http://www.vectronix.ch/#/en/products/handheld_equipment/rangefinders/vector_rangefinder_binoculars

If costs don't matter.

Generally if you're using those items someone else is definitely paying the tab and it's not birds you're after. Where can I get a price list for them, just out of curiosity? .

 

[Binastro]

. Wild is one of the best optical and mechanical manufacturers in the world.
In surveying, military lenses, advance stereo machines some of which were unique in the middle of the last century.

For instance, the 98 mm F1 .4 Falconer lenses and longer focal lengths of which I've seen photos but haven't handled. I'm not sure they were even made for production use.
The 98 mm cover 2 1/4 in square film and was used in the Vinten aerial cameras.
from memory the focal lengths are marked individually on the lenses to 0.01 mm I think at a height of 80 m for low-level aerial photography.
The photos could be taken at 500 kn and can be pin sharp.
The cameras I think had image motion compensation.

A great company.
I would certainly like one of their rangefinder lasers measuring up to 25 km but it is going to be expensive.
the only way might be to get a used example perhaps at auction.

 

[dalat]

If Leica Geovid, total station or the Vectronix rangefinder, the question for all is if the laser range finder works on flying birds. If not, then also precise angle measurements don't help much and no better results than with the described methods of guesstimating can be obtained. For finding out if it works or not, I think it should be enough to borrow and test one of those hunting rangefinders (Geovid or other), they should suffice in the distances and precision needed in the discussed purpose.

I was also thinking of printing them out but wanted to save print costs.

Is there really so little funds available for environmental studies in these multi-million projects?