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Thinking of the ATS-65 with the 25-50 ep (1 Viewer)

CSG

Well-known member
United States
I had a chance to view through an STS-65 with the 20-60 at a local store and was pretty impressed when compared to the 65mm Vortex Razor. The Razor, while nice, couldn't approach the Swaro for resolution at the end of the zoom range.

I read some older threads regarding the 20-60 vs 25-50 ep and I had no issues with the 20-60. I've read some complaints about kidney beaning with the 25-50 but I never had issues with my Nikon SE 8x32's. Maybe it's because I don't wear glasses.

So my questions to the class are: 1. As a casual birder who is astounded with himself at the idea of spending this kind of money for the 65, why would I want to spend more for the 80? And 2. If I likely stick with the 65, which ep is more all around useful, not only for birding but general long distance viewing?

I should add that Kate at Eagle Optics thought I'd be very happy with the 65, even if digiscoping (something I'd like to do with my iPhone SE).

Thanks,

Chris
 
i'm considering the ATS 65 as my travel scope. I currently own the ATS 80 with the 25-50x eyepiece.

I've just purchased a mint condition 30x SW eyepiece which I intend to use with the ATS 65 and i feel this might be the best combo with this size objective - gives a nice wide FOV and still gives me a reasonable exit pupil.

I'm concerned the zooms will be too dark at the long end i.e. 50x or 60x on the smaller scope. To be honest I havent tested that concern yet - I'm waiting on my local dealer to receive an ATS 65mm so I can try this.

cheers
Jeelan
 
I looked at the 60x setting on the STS-65 yesterday and was pretty impressed with the image quality and sharpness. Under good light, I didn't think it was dim in the least. With astronomical telescopes, we figure our max power on good glass in the range of 30-50x per inch of glass. In the case of the ATS-65, the max zoom of 60x translates to 25.5x per inch of aperture. The 50x of the 25-50 is only 19.6x per inch. Not sure if it's a fair comparison (astro vs. spotting) but I would think the calculation would translate.
 
The Swaro 65mm scopes take the 60x magnification well. The image is not too dark yet. It will show a bit more small detail than at 50x, but the difference is not dramatic. Both zooms are fine eyepieces.

For daytime viewing, with high-quality scopes, my opinion is that up to about 1x of magnification per 1mm of aperture (ca. 25x/inch) is the useful maximum. For astro viewing, the 30-50x/inch applies.

Kimmo
 
i'm considering the ATS 65 as my travel scope. I currently own the ATS 80 with the 25-50x eyepiece.

I've just purchased a mint condition 30x SW eyepiece which I intend to use with the ATS 65 and i feel this might be the best combo with this size objective - gives a nice wide FOV and still gives me a reasonable exit pupil.

I'm concerned the zooms will be too dark at the long end i.e. 50x or 60x on the smaller scope. To be honest I havent tested that concern yet - I'm waiting on my local dealer to receive an ATS 65mm so I can try this.

cheers
Jeelan

Jeelan,

You can test the brightness of a 65mm Swaro scope even before your dealer receives one. Just cut out a 65mm stopdown mask from black paper or cardboard and tape it to front of your ATS 80 sun shield. Flipping it in and out of the light path will give you an instantaneous comparison of the image brightness between 65mm and 80mm.

Henry
 
That's a really good idea. I have an 85mm Televue refractor so will do just this very thing to see if 65mm will satisfy me (although I'm trying to convince myself to simply use my 70mm Televue Pronto as a spotting scope and for digiscoping). I took this image the other day handholding my iPhone SE to a 20mm TV Plossl and was surprised at how well it worked for my very first effort with no attachment devices. This was a crop from the initial round image circle from the phone.

 
I think that photo does a good job of revealing the main optical weakness of the Pronto/Ranger scopes.They were not really very close to being true APOs. The color correction was better than a normal 70mm achromat with the same focal ratio of f/6.86, but they were only maybe about as good as a normal 70mm f/11-f/12 achromat. I recall recommending the Ranger to a friend based on the BVD review, and then being dismayed by the large amount of longitudinal CA visible at 50x. I haven't seen the TV-85, but I assume it's much better.

Henry
 
We're discussing this over at Cloudy Nights too and for visual, you just don't see much of a CA issue with the Pronto. It's imaging that reveals its flaws (or looking at the edge of the moon, etc.). One fellow over there recommended the TV-76 which, like the TV-85, has excellent color correction. It's just that for daytime field use, they are rather clunky and unsealed systems.

I'm coming close to convincing myself to just spend the $$$ on the Swaro ATS-65. I'm a fan of portability over most anything else and the 65 offers that in spades. It's a good compromise from the larger optics with their increased cost. I can see spending the money for the 65 but not the 80 and certainly not any of the ATX system, even the ATX-65.
 
We're discussing this over at Cloudy Nights too and for visual, you just don't see much of a CA issue with the Pronto. It's imaging that reveals its flaws (or looking at the edge of the moon, etc.). One fellow over there recommended the TV-76 which, like the TV-85, has excellent color correction. It's just that for daytime field use, they are rather clunky and unsealed systems.

I'm coming close to convincing myself to just spend the $$$ on the Swaro ATS-65. I'm a fan of portability over most anything else and the 65 offers that in spades. It's a good compromise from the larger optics with their increased cost. I can see spending the money for the 65 but not the 80 and certainly not any of the ATX system, even the ATX-65.

My only experience with TV was the view through a setup at Adorama in NYC using a TV-76 plus an image rectifier and a diagonal, with a wide angle eyepiece at the end. It was truly a Rube Goldberg, not something for field use imho.
The image however was really spectacularly good, so if TV ever found a way to package their glass appropriately, they would be a serious contender.
 
etudiant, that's my concern with using the Pronto much less spending a couple grand for the TV-76 and still dink around with all the accessories. TeleVue does make something called the FoneMate which is a cellphone adapter for their eps that take their Dioptrix corrector so that would be a simpler set-up.

However, since my previous post, I came across the previous generation Vortex Razor 11-48 65 which has a triplet objective. Optics Planet has a few new leftovers on ebay for less than on their own website - $799 shipped with free returns. My guess is that as good as this scope was rated in comparison to the ATS-65, I'll try it for a few days, breakdown, and return it in favor of the Swaro. ;)

Or maybe not?
 
Be sure to thoroughly test the Razor when it arrives. Here's a link to a review I did of a very defective 85mm Razor:

http://www.birdforum.net/showthread.php?t=218231

Some things, good and bad, are likely to be the same with the 65mm version. I think it uses the same very nice copy of the Swarovski 20-60x zoom eyepiece and I expect, since it uses the same prism focuser, that it will suffer from the same loss of effective aperture at close distances. Sample variation is probably no better. IMO, it's always good to consider an individual unit of any scope guilty until proven innocent.
 
Yes, I read that thread. The ep is 11-48 on the smaller scope. The reason I bought it from Optics Planet is their free return policy (the label is included with their package). So yes, I'll test it (within my own abilities) and decide from there. I also ordered the Alpen 788 (80mm non-ED scope) from Costco to check out. Very inexpensive at $400 but Costco has a warehouse in our town so it's an easy return.

Both scopes should show up this week. If neither prove acceptable, I'll go back to the Swaro and just pony up the $$$. But there will be sample variations with Swaro too. Everything always needs to be used and tested by the buyer no matter the cost.
 
Jeelan,

You can test the brightness of a 65mm Swaro scope even before your dealer receives one. Just cut out a 65mm stopdown mask from black paper or cardboard and tape it to front of your ATS 80 sun shield. Flipping it in and out of the light path will give you an instantaneous comparison of the image brightness between 65mm and 80mm.

Henry


Henry, that for that suggestion.

My dealer received their stock of the ATS 65 on Fri so i didnt get a chance to follow through on your suggestion. Instead I popped in to the store on Sat to try it out.

They are in the middle of the city but have a balcony the next floor up so he was happy for to me play around with the scope out of the way of other customers on their shop floor..

I had taken my ATS 80 and 25-50x eyepiece so spent a bit of time with each scope, swapping the eyepiece back and forth.

Physically the ATS 65 is quite a bit smaller than the dimensions themselves would suggest. Obviously its a lot slimmer but shorter as well. It definitely meets my criteria of a "travel friendly" scope.

I have a Sirui VA-5 that I use for the Swaro 80 and I'd taken a second quick release plate to attach to the bottom of the ATS 65. With the 25-50x eyepiece attached, the scope was back heavy - i had to slide the quick release plate forward by a good 30mm to allow the scope to balance on the head. Once i'd adjusted the balance, I started assessing the view..

Given I was at the store around 11am on a bright sunny day, the view really wasn't any different between the 80 and 65mm. Both had similarly sharp, contrasty views with a flat field. The 65mm objective was slightly wider when i framed the view against fixed dimensions (no. of window panes on a building about 200m away)

I tried looking at resolution in shadows but again, couldn't see any difference to my eye.

Where I DID notice the biggest difference was ease of use. I've already noted in previous threads that I'm struggling to find consistent comfortable eye placement with the 25-50x eyepiece. On the ATS 65, i found it even more finicky. Slight movements of my head would induce kidney beaning. I had reduced tolerance to tilting my head and almost had to align with the eyepiece dead straight to get a clear view... Once I started started focusing on this aspect of comparing the two scopes, i wasn't sure if it was because of the reduced exit pupil on the smaller scope or what but i just found the ATS 65 a lot LESS comfortable than the 80 particularly when switching between the two.

Now I had intended to use the ATS 65 with the Swaro 30x SW fixed FL eyepiece, but even then i assumed that the comfort level would have been identical to using the 25-50x at 25x. As I didnt have the 30x eyepiece on hand, I couldn't tell, however on the 25-50x eyepiece there was certainly a difference in ease of viewing from one scope to another...

Having accepted that the quality of the views between the two sizes would be identical in all but maybe 5-10% of my viewing, the more I focused on the comfort and viewing ergonomics, the more i saw a larger than expected gap between the two scopes - particularly when I could switch from one to another to compare...

After about half hr, I had made my mind up that I wasn't going to pursue the ATS 65 any more.

So I'm now rethinking my requirements re portability and wondering if I should just stick with the ATS 80 and make that work i.e. buy a slightly bigger backpack for travelling or even carry the scope on its own (with a SOC) slung over my shoulder - most airlines allows a separate small video/camera bag so the scope should be no different as a standalone piece of luggage...

but either way, those are my thoughts on the ATS 80 vs ATS 65.

cheers
Jeelan
 
Very interesting and thank you for posting that. In your case, it seems like it makes more sense to accommodate the scope you already own and save some significant money by doing so.

I keep thinking, as I don't do air travel, that an 80mm class scope would suit me better, especially as digiscoping will likely be one of the things I do most with whatever I end up with.

It will be interesting to compare the scopes I ended up ordering although I doubt I'll keep either. But it will give me a bit of a size comparison.
 
Where I DID notice the biggest difference was ease of use. I've already noted in previous threads that I'm struggling to find consistent comfortable eye placement with the 25-50x eyepiece. On the ATS 65, i found it even more finicky. Slight movements of my head would induce kidney beaning. I had reduced tolerance to tilting my head and almost had to align with the eyepiece dead straight to get a clear view... Once I started started focusing on this aspect of comparing the two scopes, i wasn't sure if it was because of the reduced exit pupil on the smaller scope or what but i just found the ATS 65 a lot LESS comfortable than the 80 particularly when switching between the two.

Did you compare the scopes only at 25x mag or at different mags? Did you have the scopes set up at the same height and angle etc?

At 30x the 80mm scope would have approx. the same exit pupil as the 65mm at 25x, and I guess then the 80mm scope would feel as "uncomfortable" at 30x mag, if exit pupil would be a factor.

But perhaps your pupil size at the occasion might come in to play here? If it were larger than 2.6mm at the time the 80mm might be a bit easier on the eye? Also the 80mm scope is 1 stop brighter which might affect your pupil size, even though you don't see any subjective difference in brightness.

Personally I think the ATS65 works surprisingly well even in lower light when I know that my eye pupil is larger than the EP. I think the high light transmission is an important factor.

To me it sounds more like an Eye Relief issue. Could ER differ with the same EP on the 80mm vs the 65mm scopes? It takes only 1 mm (more or less) to make a difference. Not sure if blackouts or kidney beaning are the same in this case but it might occur when ER is to long or to short.

BTW do you use glasses with scopes?

Interesting comments you have though, I'm constantly looking for good reasons to complement my ATS65 with a bigger scope.
(But I still would keep the 65mm for hikes/biking and travel.)
 
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hey mate

I dont wear glasses and as noted visually I couldn't tell any difference in the quality of the image between the two scopes - image quality was fantastic in both.

I just had a lot more issues with kidney beaning in the 65mm than on the 80. I typically have issues on the 80 anyway but going from one to the other, there felt like a big difference. After looking through the 65 where I had to keep my head very still once I found "the spot" - i felt i could move a bit more, rotate my head a bit more, on the 80mm scope without losing the FOV.

I may be getting blackout and kidney mixed up, so please excuse my language and my apologies for the confusion - the issue is kidney beaning and NOT blackout so I'm fairly certain eye relief isn't a problem. I dont wear glasses so thats not a factor either..

The earlier post is my personal observations only - on paper there may be nothing to suggest there should be a difference between the two scopes in the conditions I observed under (bright daylight), its just that ergonomically i DID find a difference which I wasn't expecting..

Again above comment are my 2c only..

cheers
Jeelan
 
hey mate

I dont wear glasses and as noted visually I couldn't tell any difference in the quality of the image between the two scopes - image quality was fantastic in both.

I just had a lot more issues with kidney beaning in the 65mm than on the 80. I typically have issues on the 80 anyway but going from one to the other, there felt like a big difference. After looking through the 65 where I had to keep my head very still once I found "the spot" - i felt i could move a bit more, rotate my head a bit more, on the 80mm scope without losing the FOV.

I may be getting blackout and kidney mixed up, so please excuse my language and my apologies for the confusion - the issue is kidney beaning and NOT blackout so I'm fairly certain eye relief isn't a problem. I dont wear glasses so thats not a factor either..

The earlier post is my personal observations only - on paper there may be nothing to suggest there should be a difference between the two scopes in the conditions I observed under (bright daylight), its just that ergonomically i DID find a difference which I wasn't expecting..

Again above comment are my 2c only..

cheers
Jeelan

Perhaps the 20% difference in EP size is the explanation.
Not the first time kidney beaning is discussed for the 25-50x Swaro EP.
And some even seem to prefer the 20-60x for that reason. Most people though seem to appreciate the bigger FOV/AFOV of the 25-50x EP.
But perhaps getting an 65mm + the 20-60x might be an alternative? o:)
Personally I probably would stick to the 80mm if I already owned it.

More on the 25-50x EP issues here:

http://www.birdforum.net/showthread.php?t=156454
 
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Just to conclude this thread, I decided to buy the Kowa TSN-88 and ordered one today from Eagle Optics. I've already arranged to return the Vortex Razor to Optics Planet (it won't even arrive until the end of next week).

I was really tempted by the ATS series and even more so the ATX series but in the end, it was $$ and the superlative reviews for the Kowa that put me into that camp. I got a very good deal from EO and they tossed in the field case at no additional cost.
 
Congratulations mate, great purchase!!

I'd love to hear your comments once you've received the Kowa.Did you buy with the 25-60x wide angle zoom?

cheers
Jeelan
 
Yes, the 25x60. Assuming I keep the scope, I'll likely add the 1.6 extender after I recover from the cost of the scope. I'm also going to want to get some new tripod legs. I have a Manfrotto 501 head and am using it at the moment on my Telepod legs. The legs are sturdy enough but not tall enough so I have to use too much center column. They are designed to use with a small refractor so don't have the height a 6 footer like me prefers, especially if I'm standing. With astro, I'm usually sitting.
 
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