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Feel the intensity, not your equipment. Maximum image quality. Minimum weight. The new ZEISS SFL, up to 30% less weight than comparable competitors.

New ATC/ STC 17-40x56 Telescope (1 Viewer)

Brummie

Well-known member
A simple towel work just fine as well. And it can be rather useful in the field.

Hermann
You can also buy cloths with Velcro tabs on the corners which are designed for wrapping around lenses (although it wouldnโ€™t be beyond the wit of man to make your own).

These days I use drawstring pouches for my binoculars (bulky manufacturersโ€™ cases stay at home), and for scopes and scope components (I have an ATX/BTX system), I use a mixture of microfiber pouches, wrap cloths and neoprene lens protectors, depending on what fits best.
 

crinklystarfish

Well-known member
Ireland
Further to my earlier reference querying actual objective lens diameter (Swarovski's own info refers to an effective lens diameter of 56mm): I further note from Swaro's website that exit pupil diameter reportedly ranges between 1.4 and 3.4mm.

56/1.4 = 40x magnification: all good.
56/3.4 = 16.47x magnification.

Alternatively:
3.4x17 = 57.8 objective lens diameter.
In which case: 57.8/1.4 = 41.29 magnification.

Am I missing something (apart from a meaningful interest in life)?

It may be considered a pedantic / academic point, but given this is supposed to be a precision optic from one of the world-leading manufacturers can anyone advise on any accurate empirical measurements for magnification / objective lens diameter / exit pupil size.

As a very occasional scope user I'm seriously considering purchase but would prefer to understand the exact spec of the optic I'd be spending a not inconsiderable amount of money on.
 

Vespobuteo

Well-known member
Further to my earlier reference querying actual objective lens diameter (Swarovski's own info refers to an effective lens diameter of 56mm): I further note from Swaro's website that exit pupil diameter reportedly ranges between 1.4 and 3.4mm.

56/1.4 = 40x magnification: all good.
56/3.4 = 16.47x magnification.

Alternatively:
3.4x17 = 57.8 objective lens diameter.
In which case: 57.8/1.4 = 41.29 magnification.

Am I missing something (apart from a meaningful interest in life)?

It may be considered a pedantic / academic point, but given this is supposed to be a precision optic from one of the world-leading manufacturers can anyone advise on any accurate empirical measurements for magnification / objective lens diameter / exit pupil size.

As a very occasional scope user I'm seriously considering purchase but would prefer to understand the exact spec of the optic I'd be spending a not inconsiderable amount of money on.
It's all within the margin of rounding errors.

56/16.5x = 17x = 3.39mm = 3.4mm
56/16.7X = 17x = 3.35mm = 3.4mm
 

crinklystarfish

Well-known member
Ireland
It's all within the margin of rounding errors.

56/16.5x = 17x = 3.39mm = 3.4mm
56/16.7X = 17x = 3.35mm = 3.4mm
I wondered about that and did all that stuff before posting. If we're to take 56mm as accurate and round the maximum parameters (for rounding) of the exit pupil diameter: then 56/3.35 = 16.72 = 17 but 56/3.44 = 16.28 = 16. Of course, as above: 56/3.40 = 16.47 = 16.

I think I'm going to buy the 16-40 x 56 version to help a little with hand-held steadiness. ;)(y)
 

Dyrlege

Well-known member
Norway
My ATC arrived a couple of days ago in burnt orange.
Yess! It is as expected, small (heavier than expected), beautiful design, wonderful handling: The "skidpad" really does work! Freehand up to 30x looks and feels acceptable, but my MM3 is going to have to give up its carbon tripod.
Not really conditions now for long-time or long-range use at the moment here in Norway, either too cold or too foggy, but in between thawing fingers (it is decidedly not easy to handle the ATC with mittens) it gives the impression of very good optical quality (and of course now no heat shimmer to degrade the view!).
๐Ÿ˜
 

Hermann

Well-known member
My ATC arrived a couple of days ago in burnt orange.
Yess! It is as expected, small (heavier than expected), beautiful design, wonderful handling: The "skidpad" really does work! Freehand up to 30x looks and feels acceptable, but my MM3 is going to have to give up its carbon tripod.
Nice! Very much looking forward to your impressions once you had a chance to use the scope a bit more in the field.

Hermann
 

gastonbe

Active member
Belgium
My ATC arrived a couple of days ago in burnt orange.
Yess! It is as expected, small (heavier than expected), beautiful design, wonderful handling: The "skidpad" really does work! Freehand up to 30x looks and feels acceptable, but my MM3 is going to have to give up its carbon tripod.
Not really conditions now for long-time or long-range use at the moment here in Norway, either too cold or too foggy, but in between thawing fingers (it is decidedly not easy to handle the ATC with mittens) it gives the impression of very good optical quality (and of course now no heat shimmer to degrade the view!).
๐Ÿ˜
As for the handling with gloves, is it more difficult than with larger scopes? I noticed that with my Swarovski Pocket CL 8x25, handling in winter with thick gloves was an issue. Although I am used to it now and don't mind the small focus wheel with gloves as much anymore. You have to get used to it a bit.

Eager to hear about your experiences too! I'll probably order mine by the end of January as most shops are still out of stock.
 

Dyrlege

Well-known member
Norway
As for the handling with gloves, is it more difficult than with larger scopes? I noticed that with my Swarovski Pocket CL 8x25, handling in winter with thick gloves was an issue. Although I am used to it now and don't mind the small focus wheel with gloves as much anymore. You have to get used to it a bit.

Eager to hear about your experiences too! I'll probably order mine by the end of January as most shops are still out of stock.
My delivery was delayed as well, they are supposed to have had a problem with colour! For the burnt orange ones, that is, green is apparently easier. It (the ATC) works fine with normal gloves (rabbit lined), I shall experiment with thicker gloves as soon as the winter fog lifts. BUT! Using a mask may be smart, there is no heating on the eyepiece,๐Ÿ™‚
 

gastonbe

Active member
Belgium
Good to hear. Did you have a larger scope before this one to compare with? Friends in the birding group are trying to talk me out of getting the ATC and into getting a bigger scope. That's fine if you bird the way they do, i.e. drive to a pool and stand there. But I usually hike/bike so I still feel like the ATC is the best choice here. It's pretty personal, I suppose. It will look funny next to their BTX's though :D
 

Dyrlege

Well-known member
Norway
Good to hear. Did you have a larger scope before this one to compare with? Friends in the birding group are trying to talk me out of getting the ATC and into getting a bigger scope. That's fine if you bird the way they do, i.e. drive to a pool and stand there. But I usually hike/bike so I still feel like the ATC is the best choice here. It's pretty personal, I suppose. It will look funny next to their BTX's though :D
I followed the advice of more experienced birders than myself and started out with an MM3 60. Great scope, lightweight and handleable. I have tried several of the larger (also Swaro) scopes and stick to the light, portable one. The ATC will (probably!) be better optically with the same weight, but the MM3 60 was a good start. I also have a 90 mm Schmidt-Maksutov telescope with all the trimmings: I prefer the MM3 60 (good out to 300 meters+) for handling and overview. Very rarely have I had to peek through a more powerful scope in order to see a bird, and in warm weather you lose distance clarity to heat shimmer anyway.
The formidable optics of the Curio 7x21 was what made me up to the ATC.๐Ÿ˜†
 

gastonbe

Active member
Belgium
I followed the advice of more experienced birders than myself and started out with an MM3 60. Great scope, lightweight and handleable. I have tried several of the larger (also Swaro) scopes and stick to the light, portable one. The ATC will (probably!) be better optically with the same weight, but the MM3 60 was a good start. I also have a 90 mm Schmidt-Maksutov telescope with all the trimmings: I prefer the MM3 60 (good out to 300 meters+) for handling and overview. Very rarely have I had to peek through a more powerful scope in order to see a bird, and in warm weather you lose distance clarity to heat shimmer anyway.
The formidable optics of the Curio 7x21 was what made me up to the ATC.๐Ÿ˜†
Funny, I feel the same way about the optics of the CL Pocket 8x25 by Swarovski. I take it everywhere, too. I can't imagine doing that even with a 8x32. The only thing I gave up was a bit of comfort in the eye cups, I feel like. That shouldn't even be the case for the ATC at all as it has the same occular as the ATX 65, if I am not mistaking.

Good to hear you came to the same conclusion as myself!

Just wondering; are you planning to use the 7x21 in tandem with the ATC or do you also have a bigger binocular? I only use the 8x25 :sneaky: But I haven't been birding for too long, yet. The Curio does seem like a great bino! I've been trying to get my girlfriend to buy one. I might need to gift her one next year for her bday, cheap as she is!
 

Dyrlege

Well-known member
Norway
Funny, I feel the same way about the optics of the CL Pocket 8x25 by Swarovski. I take it everywhere, too. I can't imagine doing that even with a 8x32. The only thing I gave up was a bit of comfort in the eye cups, I feel like. That shouldn't even be the case for the ATC at all as it has the same occular as the ATX 65, if I am not mistaking.

Good to hear you came to the same conclusion as myself!

Just wondering; are you planning to use the 7x21 in tandem with the ATC or do you also have a bigger binocular? I only use the 8x25 :sneaky: But I haven't been birding for too long, yet.
I found myself using the curio and the MM3 60 in combo supported by a 10x40 habicht, the ATC will take the MM3's place. 70% curio, 30% Habicht, six other pairs rarely make it out of the house, so you might say the plan is ATC/Curio (+Habicht): totalling ca 3 kgs with tripod...
 

gastonbe

Active member
Belgium
I found myself using the curio and the MM3 60 in combo supported by a 10x40 habicht, the ATC will take the MM3's place. 70% curio, 30% Habicht, six other pairs rarely make it out of the house, so you might say the plan is ATC/Curio (+Habicht): totalling ca 3 kgs with tripod...
Is that with Habicht included? Nice spec!
The Habicht is pretty bulky in volume though. Is it mostly for weight you choose a Habicht as your secondary bins? How do the Curios compare in eye cup comfort to larger bins?
 

Dyrlege

Well-known member
Norway
Right! It was a cold, but not stormy, night. -7, clear and bright skies, perfect to try out the ATC.
Winter gloves: no problem. Focus and zoom easily handled.
Magnification and freehand? Looking at stars I could see my heartbeat (stars bouncing) but with a little support from a wall I could see the Orion nebula. And Mars. Pinpoint stars.
Looking at terrestrial targets not so apparent bouncing until I got to 30-ish magnification, again: with a nearby allied wall viewing was ok. I shall be using a tripod most of the time though.
Tha handling with thick winter gloves was, well, not a surprise, more of a confirmation that it is a fieldable, all-season tool.
Excellent optics. As should be. Just like little sibling Curio.
,,,,๐Ÿ˜
 

William Lewis

Wishing birdwatching paid the bills.
United Kingdom
Right! It was a cold, but not stormy, night. -7, clear and bright skies, perfect to try out the ATC.
Winter gloves: no problem. Focus and zoom easily handled.
Magnification and freehand? Looking at stars I could see my heartbeat (stars bouncing) but with a little support from a wall I could see the Orion nebula. And Mars. Pinpoint stars.
Looking at terrestrial targets not so apparent bouncing until I got to 30-ish magnification, again: with a nearby allied wall viewing was ok. I shall be using a tripod most of the time though.
Tha handling with thick winter gloves was, well, not a surprise, more of a confirmation that it is a fieldable, all-season tool.
Excellent optics. As should be. Just like little sibling Curio.
,,,,๐Ÿ˜
Cost not withstanding this sounds like a great idea for a scope and binocular set -perfect set for a bit of back country backpacking and probably all you really need most of the time.
 

Hermann

Well-known member
Winter gloves: no problem. Focus and zoom easily handled.
Sounds good. My little Nikon ED doesn't handle all that well with thick mittens.
Magnification and freehand? Looking at stars I could see my heartbeat (stars bouncing) but with a little support from a wall I could see the Orion nebula. And Mars. Pinpoint stars.
Looking at terrestrial targets not so apparent bouncing until I got to 30-ish magnification, again: with a nearby allied wall viewing was ok. I shall be using a tripod most of the time though.
You may want to try using a decent monopod if you want to keep the weight down as much as possible. That should work nicely with the Swaro. Handheld ... Well, it sounds as though yon can do without any support if necessary, but you really want some support out in the field. There aren't too many convenient walls out in the fjells ... :cool:
Tha handling with thick winter gloves was, well, not a surprise, more of a confirmation that it is a fieldable, all-season tool.
Excellent optics. As should be. Just like little sibling Curio.
,,,,๐Ÿ˜
Great. I may have to have a long look at the ATC. I switched to using glasses instead of contact lenses last spring, and the zoom eyepieces of my Nikon Fieldscopes don't work very well with glasses. The FOV is pretty small anyway, and with glasses it's abysmal. At the moment I mainly use DS eyepieces, but a good zoom is undoubtedly a heck of a lot more convenient.

Thanks a lot for your impressions. No doubt you'll add more when the conditions improve and you use the ATC more in the field.

Hermann
 

Yealm

Active member
UK shops seem to have it in stock as from today !

I compared it to the ATS 65.
Optically amazing - in fading Winter afternoon overcast light, at full magnification (ie 40, compared to 50 on the ATS), reading a distant farm signpost was slightly harder with the ATC, but marginal.
Subjectively, not a great deal lighter in weight, but a lot smaller.

The big flaw - lack of a rotation-prevention pin recess.
The shop assistant tightened it 3 times to the tripod head plate, and 3 times it worked loose - I think difficult to avoid torque forces during focussing and zooming, maybe only way to prevent this would be to glue it to the tripod head plate - then making it difficult to use without a tripod.

I'm really torn - I love it apart from this (in my eyes) major flaw !
 
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gastonbe

Active member
Belgium
UK shops seem to have it in stock as from today !

I compared it with ATS 65.
Optically amazing - in fading Winter afternoon overcast light, at full magnification (ie 40, compared to 50 on the ATS), reading a distant farm signpost was slightly harder with the ATC, but marginal.
Subjectively, not a great deal lighter in weight, but a lot smaller.

The big flaw - the lack of rotation-prevention pin.
The shop assistant tightened it 3 times to the tripod head plate, and 3 times it worked loose - I think difficult to avoid torque forces during focussing and zooming, maybe only way to prevent this would be to put a lot of glue in the screw hole and/or around the base of the scope screw hole, to fix it to the tripod plate - making it then difficult to use without a tripod.

I'm really torn - I love it apart from this (in my eyes) major flaw !
As Hermann mentioned in the thread before, didn't all scopes use to be without this pin in early days? I'd just make a habit of checking it habitually. Strange it would come loose that quickly though.
 

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