Big Big Scopes

[Nick-on]

I was thinking (always dangerous, rarely productive) while replying to another thread, that people use birding bins for looking at the moon, stars etc. why do birders not use 'Astro' scopes for looking at birds? I remember looking through a Questar at an (THE) Ancient Murrelet many years ago and being amazed at the view. What was a blob through my TSN2 was now a bird! At the time everybody raved about the Questar but couldn't afford it, unlike the 'Money No Object' birders of today who like to buy the most expensive kit as a matter of course. The Questar was just a rejigged astronomical scope made slightly more birding friendly. Also on the Betterviewdesired website there is an article detailing the merits of some of the smaller astronomical scopes, so why don't I ever see any? Are they really no use? Surely everybody has looked at a dot in the distance and wished for more power. I was in the lake district a couple of weeks ago looking at the Golden Eagle (big dot) and the Ospreys (small dot) and really wished for something that would give me about 90x at least! Maybe not for everyday use but as an alternative now and then when needed.
Has anybody got an astro scope that they use for birding and is it any good?? Keep seeing Meade 70 and 90's on e-bay going for relatively 'little' money (£250 or so) and am tempted but unsure. Are they worth it and are they useful?

[Edward]

When I was in Monfrague in April at the famed Portilla de Tietar a good site for Bonelli's Eagle and Eagle Owl, we came across a man sitting on a deck chair next to a monstrous construction, a huge astronomical telescope. He invited us to look through it and there was an adult Eagle Owl sitting on a rock at 150x magnification (according to the German owner) and the image was very clear. However, the thing weighed a ton, well many kilos at any rate, and the owner said that he never took it more than a couple of feet from his car. Don't know the make, but it looked like something the Russian army would have used in the 1950s! So lack of portability is one reason you don't see them much I suppose and aren't they more fragile? Must be great for looking at waders though!
E

[Steve J - Darlo]

Nick-on

I did a bit of research into big Astro scopes for birdwatching before I bought the Opticron. The problem, I was told by the suppliers, with them is not only the weight but also the delicate mechanism that they use to generate the image and I was advised that they could easily be damaged in the 'field'

If you were to have a static set up, such as a hide or the house they would be superb as that is what they are designed for.

Steve J - Darlo

[rile's]

There is no comparing some the new HD scopes with just about anything else. When comparing my Zeiss scope next to a Mead scope the image is much, much, more clear. And this difference is magnified (no pun intended) when in low light situations.
It is hard to imagine or believe it unless you can look into the scopes side by side.
Same goes for non HD scopes. When comparing side by side the non-hd scopes seem like they have a dirty, dark, filter over the lens. But you don't notice this when looking through different scopes by themselves.

[Nick-on]

That's the sort of use I had in mind really, near the car or in a hide (you know, the 'lazy way'). why walk 4 miles to see something when you can sit next to your car and see it?
I know that reflecting scopes are a bit delicate but they can be reset fairly easily, so I'm told.
BTW Edward wish I'd had any view of an Eagle Owl ( let alone one at 150x) when I was in Monfrague, I looked at that cliff face until my eyes hurt!
I can't help thinking that I'm missing out by not having one when needed (perhaps I just want a new toy?).

[Nick-on]

Morning Rile's,
I quite believe that optically the Zeiss is better at 'normal' magnifications but is it worth having a scope that can go up to +100x although I suppose with the release of 100mm 'spotting' scopes there will be greater powered eyepieces available?
Is it better to have a razor sharp dot or a (slightly?) fuzzy bird???

[Tannin]

Originally posted by Nick-on
why walk 4 miles to see something when you can sit next to your car and see it?

I don't think astro scopes are that powerful, Nick. ;)

[Andy Bright]

It always seems to me as if using astro scopes for birding is far more popular in N. America.... maybe because they have backyards the size of our counties and just set them up on their back porch and survey their kingdoms.
The fact that many U.S. states are drier than the U.K? Big problem is that astro scopes are not waterproof (certainly not usually), can be very heavy beasts and certainly not as robust as our 'typical' birding scopes.
Andy

[normjackson]

As with astro viewing I guess viewing conditions will largely dictate whether a higher specified scope will deliver better viewing. I've also seen the article in BVD and seem to recall that the author suggested that 60x magnification was about the "normal" useful limit for terrestrial use (because of water vapour, atmospheric pollution etc). The lastest top quality spotting scopes now seem to return excellent quality at that level of magnification with the conveniences of a correctly orientated image, a zoom eyepiece with an adequate FOV all in a waterproofed and robust package.

If you do really want higher magnification than this, you may be able to try astro eyepieces with your top quality terrestrial scope at the price of some fall-off in image quality. If you want to maintain quality, and conditions allow, then an astro telescope is probably the way to go.

There's an Adobe Acrobat pdf file (in Norwegian!) with a table which attempts to put figures to what a selection of astro and terrestrial scopes achieved at different magnifications at :

www.kikkertspesialisten.no/index2.htm

Click on Teleskop on the left, then scroll down a bit. Right click on the top "Hent Test" and "Save Target as..." to somewhere convenient. It's a 769kb download, but the table has reviews and piccies of a lot of the major players. The test results in the centre are for sharpness, contrast, brightness, edge sharpness, convenience with specs and robustness. Left hand side names eyepieces and corresponding magnification.

And here's a link to a pdf file from a Birdwatcher's Digest review (would make a good lens testing chart). I have a copy of the accompanying text but have lost the link :

www.birdwatchersdigest.com/backyard_birds/scopes03.pdf

This last review suggests that the Celestron C5 achieved resolution results at 45x magnification nearly as good as those achieved by the top spotting scopes at 60x. Maybe there's a candidate for your next toy, Nick, at a mere half a grand?

A picture and spec of the Celestron C5 is at www.dhinds.co.uk in the spotters/binos section.

I've bumped into a few astro telescope users on this forum, but I guess it would be a bit too cheeky to PM them to ask for their views :frog:

Norm

P.S. Sorry for the two edits. I'd forgotten info I was referring back to was spread over two quite big threads.

[cspratt]

I have an Orion F/5 shorty refractor made in China for the US/Canada market. Okay visually but not good for photography (astro or birding), as too much chromatic aberration (false colour). The scope can't go much over 60X before the image "falls apart". It also insn't water or dust proof so for birding in the woods it wouldn't last five minutes.

One thing about most astro scopes is the fact they are designed with non-bayonet eyepiece holders. That little holding set screw can loosen off really quickly and there goes the eyepiece or diagonal or both crashing to the ground. The Televue are a bit better with a groved eyepiece holder o the set screw can be tightened in the grove. Still not that good in my opinion.

The Questar gives great images but isn't robust enough for field work. For the money I would get the Zeiss as it is 85mm and the Questar 89.
The Meade and Celestron Maksutovs again aren't "robust" and won't last in the field. Bad enough at night when doing astronomy work!

I've been an amateur astronomer for 40+ years and know the cost of breakages no matter how careful one is.

Stick with good birding (APO) scopes and you will be far better off in my humble opinion.

Chris. Spratt
Victoria, BC.
MPC Astrometry site #642 (Oak Bay, Victoria)

[rile's]

Yes this durability thing is very important. I have packed my Zeiss scope hundreds of miles in the last 7 months. And last month on the South Fork in Arizona it tipped over and sailed down a cliff........
Ahhhhhh, but I was real lucky, it landed sideways and a knob on the tri-pod took the brunt of the blow Then the scope popped off and slide 20 feet down the rock slope. Luckly the scope also slide sideways down the slope as the lens caps were not on. A lens end forward slide would have damaged the lens.

Ridiculously lucky as there was not a smuge on the scope.
But it illustrates a point. That these scopes go through an awful lot of dirt, dust ,packing, and banging around. And if you are dumb like me ya need an indestructible scope.

Also I pack that sucker 15 hours on some days. If it was anything more than a few pounds I wouldn't be able to do this.

And 60 power is enough, especially considering that when multiplying 4x optical zoom on the camera you are looking at 240 power.

[davebroadley]

A friend took his newly acquired Questaron a trip to Namibia and on the 1st fullday set up the scope and went for a pre breakfast walk, he soon found out that heat and vibration in the bus during their transfer from the airport to the lodge had soften the glue that holds the mirrors and they were mis-aligned. It was repaired by Questar very quickly, but it ruined his holiday

[normjackson]

I'm sure Chris is correct. I'm sure many have experimented with astro scopes in a birding context and have come round to the conclusion that "life's too short". The only really compelling reason I've seen for going down this route is for those who intend having a go at digiscoping, MUST have good quality images with little CA and simply can't afford an ED glass spotting scope. The only option then open to them is a small Maksutov. They will then have to adapt to the, possibly severe, inconveniences this imposes.

BTW don't have first hand experience, but have heard from independent sources that the Intes Astele scopes are a bit more robust than the average. Don't know if that played a part in them being the choice of the owners of the oft-mentioned-by-me www.jayandwanda.com site.

Would be interesting to hear from someone who's tried their Swarovski with a short fl astro eyepiece (I expect the adaptor costs a few pennies). The Norwegian review I mentioned seems to indicate quality is still pretty high with a 4.8mm Nagler to give 96x magnification, but drops a bit more with a 3mm Radian to give 153x.

[Lewis]

"It always seems to me as if using astro scopes for birding is far more popular in N. America.... maybe because they have backyards the size of our counties and just set them up on their back porch and survey their kingdoms. "

We do not! Geez Louise....

[normjackson]

Right, Lewis. I certainly don't subscribe to all these national stereotypes. It's simply not true that all Brits are frustrated anglers; over here barbed comments frequently "get a bite". Anyways, I have it on good authority that Andy is actually quite meticulous in scraping the congealed doner kebab fat off his Union Jack shorts every summer before his holiday in Spain 3:-)

[alan_rymer]

Never tried it, but, Opticron do a 100x HDF eypiece for their 80mm scopes and on the ES100 HD that is 134x.
At that magnification and Field of View trying to find a bird half a mile away must be almost impossible. Unless you use a 20x to find it, Lock the tripod head, change eyepieces and hope the birds still there!.

[normjackson]

Like Nick, I do wonder as the quality of the top spotting scopes continues to rise whether more manufacturers will start to offer more of these very high magnification eyepieces. But would they need "Sahara light", clean still air, mega tripod etc etc? I guess, as always, the consumer will ultimately decide their fate.

Good point Alan. I'm sure quite a few digiscopers would be happy to be able to purchase a finderscope custom made for their scopes. Maybe that's an "opportunity" some manufacturers are looking into now...

[Tannin]

I had that same thought, Norm - a "spotter scope" for my ATS80. I imagine that a small, low-power, telescopic sight designed for a rifle might do the trick. But as time goes by, I'm getting better at using the tiny sighting device Swarovski provide and sometimes (depending on the circumstances) just doing it by guess and by god. So my urge for a sighting scope is not as strong as it was.

What I'd really like is a thing that would look rather like the tiny music stand that sits on top of a trombone, only it would be an LCD screen, maybe 6 inches square, which takes a feed direct from the camera. No more framing and focusing by guesswork!

It would be hell on batteries and cost a fortune, of course. But I'd happily lug the batteries around and, sooner or later, pay the asking price.

Tony

[alan_rymer]

Tony
In theory batteries shouldnt be much of a problem. Current laptops have a 15"TFT LCD and the batteries last for up to a couple of hours.
Thats a thought, connect up the camera direct to a laptop and use the laptop LCD to focus, download from camera to laptop as a field backup?.

[Tannin]

The thought has crossed my mind, Alan. The business of getting an appropriate connection between camera and computer, though, would be non-trivial.

[alan_rymer]

Tony

I have an old Sanyo VPC-G200, No Zoom 640x480 Max and download the photo's via the serial port into MGI Photosuite SE software which came with the camera. From the PC I can use the MGI software to take the photo's remotely rather than locally from the camera. I would have thought there must be some way of doing this from most digital camera's?.

O.K. Thats an assumption!.

[Andy Bright]

Originally posted by normjackson
Right, Lewis. I certainly don't subscribe to all these national stereotypes. It's simply not true that all Brits are frustrated anglers; over here barbed comments frequently "get a bite". Anyways, I have it on good authority that Andy is actually quite meticulous in scraping the congealed doner kebab fat off his Union Jack shorts every summer before his holiday in Spain 3:-)

I'll have to put a smilie next to subtle humour like this next time.... not that I'm assuming all N. Americans are unable to understand it ;)

[Lewis]

"Andy is actually quite meticulous in scraping the congealed doner kebab fat off his Union Jack shorts every summer before his holiday in Spain "

This N. American didn't get it. And I'm a big-enough birder to admit it, so there!

[Dave Smith]

Sorry I'm a bit late joining this thread. I have 3 scopes, one primarily for birdwatching and two for astronomy. My Swarovski 80AT HD I do also use for astronomy and for that purpose use astro eyepieces. The shortest focal length being a 4 mm Lanthanum and yes the tiny adapter is quite expensive for what it is but has been very useful to me. With the 4mm I have seen the red spot on Jupiter and can see the Cassini division on Saturn. For non-astronomers that is the gap in the rings which you can see on my avatar. The beauty of using the Swaro for astronomy is the speed of setting up and clearing away.

My astro scopes are an 8 inch VC200L (Vixen) and a 12 inch Orion Optics (UK) newtonian. They are superb for astronomy but I have never seriously considered them for birdwatching. The first snag is the 15 minute setting up time, secondly each scope with its tripod and mount take up the boot and back seat of the car. Once set up there is no way that it can be moved quickly. On top of that I imagine there will be few occasions when the air is stable enough to benefit from higher magnifications. So, for me its a non-starter.

I also haven't considered using the astro eyepieces with the Swaro for birdwatching. I have been satisfied with the 20 - 60x zoom or 30x wide angle. I do not particularly want to carry more eyepieces around with me. The scope, tripod, camera and adapters are enough.

I hope this is of some help. Images of my astro scopes can be seen on my website.

[normjackson]

Thanks Dave. Just the sort of input we were hoping for :t:

Enjoyed the website very much. Perhaps you'll be off to Abberton next Saturday for the guided tour on butterflies and dragons. Dragonflies look alarmingly addictive as an interest...

[Art Thorn]

I've been taking my Celestron C5 with a 2" diagonal and two Televue Nagler eyepieces (13 and 17mm) to watch shore birds for about a year now. The Naglers give superb definition at very wide fields, and the C5 seems up to the task of supplying them what they need. I bought all on eBay, at very good prices, though Naglers are hard to come by. Yes, it is heavy (the eyepieces seem to weigh a couple of pounds each), but all goes into the case and that is easy to carry. With a quick release on the tripod, setup is quick and easy. People do stare though. With about 100 and 80 power on tap, I can see the specks in the distance very well, with the 'seeing' conditions (heat waves)always being the limit. I've had no problem with durability, but this setup is not waterproof. At the price, I don't think I could find anything to match the view. And this scope will set up for digiscoping very easily! Plus the views of the planets on those nights when I go out are amazing too!

[Denis]

Does anyone know if Astro eyepiece adaptors are available for the Kowa 824?

Ta

Denis

[jwaldo]

The closest thing I have to a "birding scope" is my Orion 70mm refractor, which gives great views of everything :). And I've turned my 8" reflector to the birds several times, always with amazing results ;)

[Tim Allwood]

weight and portability put me off straight away

a shoulder pod and lightwieght 60 mm scope is heavy enough for me. I still like to use bins as much as possible and only resort to a scope when i really have too

[Mickymouse]

I thought Astro scope images where allways upside down:-(

Mick

[Bluetail]

Left to right, isn't it, Mick? Certainly the Questar reversed the image. I remember once trying to track some flying Shelduck with one. A weird experience that was!

[Jay Turberville]

I don't know how I missed this thread. Sorry for being late to the party.

It happens that I recently finished a little web page that discusses digiscoping with catadioptric scopes. This is usually what people refer to when discussing astro scopes.

http://www.jayandwanda.com/digicat/digicat.html

I've been digiscoping with catadioptric scopes for about 1 1/2 years and with an ATS80HD for about 8 months. Neither is a clear winner in all aspects of digiscoping.

I have also done some viewing with the catadioptrics and consider the ATS80HD a better scope for that purpose in most situations. Here are some of my thoughts.

The Cats, as a group, have superior correction for chromatic aberrations. Period. End of story. But they have long focal lengths and central obstructions. The long focal length means the eyepieces must be longer than for typical birding scopes. Most cats small enough to be considered for use by birders have 70mm - 127mm apertures and 1.25" eyepiece holders. This smaller diameter eyepiece holder limits the FOV with lower power/longer focal length eyepieces. The result is that the wider views are often only available at high magnifications. No amount of clever eyepiece design will get you past about a 43 degree AFOV at 30x on a 1200mm focal length scope that uses 1.25" eyepieces. Things can improve with 2" eyepieces.

Furthermore, at low powers, the shadow of the central obstruction can be large enough to cause an unstable view when using the scope in daylight while your pupil is small. The exit pupil gets smaller at high powers and this problem diminishes.

So in the end, these scopes tend to do their best at 30x and above.

There are now two catadioptric scopes that claim to be waterproof. I think one also is nigrogen filled and claims to be fog-proof.

As for fragility, I've been lugging my LOMO 95, LOMO 70 and Rubinar Lens/scope around the desert (SW Arizona) for some time and in very high heat at times and they are holding up fine. The seem to handle the cold as well. I don't know how durable the $200 Chinese scopes are, but I would assume that with reasonable care they too would not be a problem. And even it isn't so robust as to withstand a fall down a cliff, the $200 price makes such a loss less dear.

My LOMO 70 is extremely compact and easy to carry around. I can imagine that many birders would be happy with it as a scope to carry in the car at all times and/or as a second scope. It has a shorter than normal focal length so it does better at the mid and low powers. It also has a nice peep site built in and a very smooth focusing knob.

I've been thinking about writing up some reviews on these scopes. Maybe I will this summer. These scopes can make a lot of sense for digiscoping where the wide FOV issue is often not a big of an issue. In fact, the long focal length eyepieces often have long eye reliefs which means that these scopes can work better with cameras like the CP5400 that simply won't behave with a typical birding scope. They make less sense for general birding, but still can work quite well if you don't mind a narrower FOV at the lower powers. This can be an excellent compromise for the birder on a budget - especially since Celestron is now offering the C90 as a waterproof scope for under $200.

[Jay Turberville]

It always seems to me as if using astro scopes for birding is far more popular in N. America.... maybe because they have backyards the size of our counties and just set them up on their back porch and survey their kingdoms.

We don't have backyards that large. Note how the mountains obstruct my view.
http://www.jayandwanda.com/scenicpics/sunrise4wanda.jpg

Actually, that's a golf course just beyond our backyard and our actual backyard isn't even 20 feet deep.

[Jay Turberville]

I thought Astro scope images where allways upside down:-(


Ya gots options with astro scopes. You can use an inexpensive 45 degree roof prism and take a small hit on image quality. You can get an expensive 45 degree roof with the phase correcting coatings ($200 or so) that will look superb. You can get a straight through porro psim that will look as good as the expensive roof but at half or less the cost. But it will be bulky. You can use a mirror finder, but it will only erect the image. It will still be reversed right and left. And then you can always view it upside down and backwards.

[henry link]

Jay, Who is making a 45 degree roof prism with phase coating? Henry

[Jay Turberville]

Jay, Who is making a 45 degree roof prism with phase coating? Henry

I was thinking it was William Optics or TeleVue, but as I went to check it out, it seems that my memory has combined data to make new and false data. :)

There is an Amici Prism that is phase corrected and of very high quality. But it is not a 45 degree prism, it is a 90. and is made by Baader Planetarium.

http://www.alpineastro.com/optical_accessories/optical_accessories.htm#amici%20summary

So perhaps there isn't a 45 degree phase coated 1.25" erector. I'll prbably nose around a bit more to see if I can scare one up.

BTW, there is a fourth option. TeleVue has a 60 degree erecting mirror. finder.

[AlanFrench]

\
[SNIP]
So perhaps there isn't a 45 degree phase coated 1.25" erector. I'll prbably nose around a bit more to see if I can scare one up.

BTW, there is a fourth option. TeleVue has a 60 degree erecting mirror. finder.

Mirror diagonals, if you sit behind the scope and look downward into them, give an erect but mirror reveresed image. The mirror reversed image bothers some folks, and the correct scope motions take a little getting used to, but you will get the best possible view this way.

I've been using a 90mm f/5 APO as a birding scope for years now, and it provides incredible views. I usually use 64x and often find 94x gives an improved view. At distances of 50 to 100 feet such powers on a quality scope give fantastic views. This is not a scope I carry through the woods, however, but there is a lot to see from the shore of a lake or the edge of a clearing.

Clear skies, Alan

[henry link]

Jay, Thanks for the link to the Baader diagonal. Henry

[Jay Turberville]

Jay, Thanks for the link to the Baader diagonal. Henry

Henry,

You might find this link interesting. Its all done with mirrors. :)

http://www.page.sannet.ne.jp/mazmoto/intro-e.htm

[henry link]

Jay, Thanks, I did find that interesting. Too bad the 2" diagonal is so expensive. It probably requires 8" of in focus and weighs 3 lbs. Henry

[Jay Turberville]

Jay, Thanks, I did find that interesting. Too bad the 2" diagonal is so expensive. It probably requires 8" of in focus and weighs 3 lbs.

Yep. And from the standpoint of using a small cat for relatively inexpensive digiscoping, it completely defeats the purpose. OTOH, Unless I missed something, I see no real reason that such a device couldn't be produced for far less money. The 1.25" isn't exactly cheap either.

[hinnark]

Hi,

there are 2 eyepieces exclusive for the Zeiss Diascope offering by a German astro manufactorer called Baader Planetarium. One with 140x magnification and of 20x (greater field of view than Zeiss own 30x ep). Unfortunately I didn´t found somebody who could report about experiences with them.

Steve

[jvanoyen]

I was thinking it was William Optics or TeleVue, but as I went to check it out, it seems that my memory has combined data to make new and false data. :)

There is an Amici Prism that is phase corrected and of very high quality. But it is not a 45 degree prism, it is a 90. and is made by Baader Planetarium.

http://www.alpineastro.com/optical_accessories/optical_accessories.htm#amici%20summary

So perhaps there isn't a 45 degree phase coated 1.25" erector. I'll prbably nose around a bit more to see if I can scare one up.

BTW, there is a fourth option. TeleVue has a 60 degree erecting mirror. finder.
Jay, does that Lomo 70mm have removable eye pieces. If so what is the smallest magnification on, say 15x?
Thanks!
Jerry

[Jay Turberville]

Jay, does that Lomo 70mm have removable eye pieces. If so what is the smallest magnification on, say 15x?
Thanks!
Jerry

Yes, it does have interchangable eyepieces. It uses the standard 1.25" astronomical eyepiece.

I'd suggest staying at around 20x. But that is going to be hard since the scope has a relatively long focal length. I'm pretty sure mine is 800mm without using a mirror finder. But I've read that some are more like 900mm. That puts you at or above 25x with a 32mm TeleVue. But this is still a viable approach. You just need to be careful and use less camera zoom.

I'd look for a 25mm eyepiece with around 20mm of eye relief if you can find one.

Either that, or think about a Rubinar 1000mm lens instead.

I'd also suggest that you read my article discussing the pros and cons of catadioptrics before spending any money.

http://www.jayandwanda.com/digicat/digicat.html

[mrpjdavis]

I'd also suggest that you read my article discussing the pros and cons of catadioptrics before spending any money.

http://www.jayandwanda.com/digicat/digicat.html

What a superb article, Jay!

Thanks for that.

Pete