Tmathews55
Active member
I believe these are far too big with too many rings I’ll try again
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Any customer review of new tsn-99? (1 Viewer)
- Thread starter jcwu88
- Start date
Tmathews55
Active member
Cannot get any good photos in the 5-6 ring range..
tried several different distances and conditions, one side of the focus is pretty clear to my eye with round concentric rings.. other side I was able to very faintly make out some rings during 1 out of 3 tries
BoldenEagle
Well-known member
Yes these have too many rings to be sure but in my opinion there can be seen spherical aberration as on the other side there is bright central area and no very clear rings and on the other side central area is dimmer and outer rings quite clear. Looks a bit same kind of zonal(?) errors which were present in the sample Henry Link tested and attached the pictures earlier (there it was reverse as the bright central area appeared with clear rings on inside focus and I believe here it is on the outside focus pattern).
Astigmatism and coma probably can't be seen this far outfocused patterns anyway. You could try to focus about 2-5 rings on either side and describe what you can see if you can't take any pictures. It may be a bit difficult if you can't get more than 70x mag.
Regards, Juhani
Tmathews55
Active member
Thanks Juhani I’ll try to get better pictures in better conditions and report back
BoldenEagle
Well-known member
Today I got a fifth sample of Kowa 993.
This sample had some quite obvious astigmatism, vertical yellow prism line was very visible with blue lines on both sides and it also had overcorrection of spherical aberration. The result was noticeably worse image quality than my Kowa 883 sample when compared directly side by side.
I took these pictures indoors at very close distance (about 8 meters) but I also checked my 883 diffraction patterns and they were same as before with longer distance. These pictures are very poor quality and they may show coma which I didn't see with naked eye, astigmatim is as it was and also spherical aberration is about what it was. Inside focus showed one overly bright outer ring and couple very faint inner ones and then just "hollow dimness", outside focus had really thick outer ring and clear inner ones of same brightness. Inside picture has some artefacts from my phone camera.
So this sample continues the not so glorious saga and goes back to the dealer...
Regards, Juhani
This sample had some quite obvious astigmatism, vertical yellow prism line was very visible with blue lines on both sides and it also had overcorrection of spherical aberration. The result was noticeably worse image quality than my Kowa 883 sample when compared directly side by side.
I took these pictures indoors at very close distance (about 8 meters) but I also checked my 883 diffraction patterns and they were same as before with longer distance. These pictures are very poor quality and they may show coma which I didn't see with naked eye, astigmatim is as it was and also spherical aberration is about what it was. Inside focus showed one overly bright outer ring and couple very faint inner ones and then just "hollow dimness", outside focus had really thick outer ring and clear inner ones of same brightness. Inside picture has some artefacts from my phone camera.
So this sample continues the not so glorious saga and goes back to the dealer...
Regards, Juhani
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Tmathews55
Active member
Is it normal using the sun spot off an object for the rings to get clearer as your eye gets adjusted to the brightness?
Passed focus im able to see a thick, solid, round ring with 2-3 distinct inner rings
Before focus I have clear distinct rings but not distinct outer ring.. they just appear to continue and fade out
This is the best I’m able to get on camera outside of focus, anything smaller on camera is just a bright circle
So I’m sitting here outside in good conditions
Passed focus im able to see a thick, solid, round ring with 2-3 distinct inner rings
Before focus I have clear distinct rings but not distinct outer ring.. they just appear to continue and fade out
This is the best I’m able to get on camera outside of focus, anything smaller on camera is just a bright circle
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Juhani,
Your latest pictures also show what looks a little like pinched optics. I'm referring to the triangular shape of the inner rings and what looks like brighter points in the rings at the corners. This could just be an artefact of the photos, but I had long time ago a Nikon ED 78 A which had this, and an optical technician friend managed to isolate the cause to the focussing doublet, which had apparently been cemented together with a little too much pressure. He re-cemented it, which improved things, and then managed to obtain a replacement doublet which was perfect and improved the image further.
Other than that, I'm not sure I've seen pinching in spotting scopes. If this actually is pinching, it would add another aberration into the growing list of 99's sins.
- Kimmo
Your latest pictures also show what looks a little like pinched optics. I'm referring to the triangular shape of the inner rings and what looks like brighter points in the rings at the corners. This could just be an artefact of the photos, but I had long time ago a Nikon ED 78 A which had this, and an optical technician friend managed to isolate the cause to the focussing doublet, which had apparently been cemented together with a little too much pressure. He re-cemented it, which improved things, and then managed to obtain a replacement doublet which was perfect and improved the image further.
Other than that, I'm not sure I've seen pinching in spotting scopes. If this actually is pinching, it would add another aberration into the growing list of 99's sins.
- Kimmo
Tmathews55
Active member
Can anyone answer a couple dumb questions for me..
First, are lemons made up of eyepiece issues? Scope body? Or combo of both
Second, I’m not exactly a bird watcher but using this scope for watching deer/elk etc.. does a poor star test translate to poor clarity when looking at an animal through it?
First, are lemons made up of eyepiece issues? Scope body? Or combo of both
Second, I’m not exactly a bird watcher but using this scope for watching deer/elk etc.. does a poor star test translate to poor clarity when looking at an animal through it?
I would think that poor objectives is the main culprit plus all other optical elements.
Also centration, wedge, tilt effects.
The accurate spacing is also important with each element really needing its glass specification entered into a computer programme and tailor spaced. I doubt that this happens.
Spotting scopes, especially in larger sizes have very fast, compressed optics.
The curves may be strong and difficult to make.
It is possible the Kowa problems stem from fluorite crystal being difficult to work with.
In fact good observations can be made, and are made, with poor telescopes.
Especially with the low magnifications used with spotting scopes.
For planetary observations very good telescopes are used if possible.
But even here, good observations are made with poor telescopes, so long as the limitations of the telescope, observing conditions and observer are known.
One good observation is worth one thousand bad observations.
But scopes do not have to be perfect.
Personally, I have had near perfect telescopes.
But many observations have been made with average quality scopes.
Regards,
B.
Also centration, wedge, tilt effects.
The accurate spacing is also important with each element really needing its glass specification entered into a computer programme and tailor spaced. I doubt that this happens.
Spotting scopes, especially in larger sizes have very fast, compressed optics.
The curves may be strong and difficult to make.
It is possible the Kowa problems stem from fluorite crystal being difficult to work with.
In fact good observations can be made, and are made, with poor telescopes.
Especially with the low magnifications used with spotting scopes.
For planetary observations very good telescopes are used if possible.
But even here, good observations are made with poor telescopes, so long as the limitations of the telescope, observing conditions and observer are known.
One good observation is worth one thousand bad observations.
But scopes do not have to be perfect.
Personally, I have had near perfect telescopes.
But many observations have been made with average quality scopes.
Regards,
B.
Tmathews55
Active member
This is the best test I’ve been able to get so far.. this is pretty close to what I’m seeing with my naked eye.. help interpreting? 
BoldenEagle
Well-known member
Kimmo, you are right. The triangular shape was also seen with naked eye. I didn't see any bright corners when oufocused as far as in the pictures but with just 2 rings I wondered why the central ring seemed to be more like 3 bright dots close to other rather than uniformly round one, could that indicate this pinching also?
I saw this triangular shape with one earlier sample and it was perhaps even more obvious.
I made a mistake by judging this sample had overcorrection of spherical aberration since it was of course undercorrection as it has been with others samples so far!
Can you share your experience how many 993 samples you have seen, as one of them was really good one? Perhaps the more interesting piece of knowledge would be how many bad or mediocre samples you found before that good one? Would you say that getting a good 993 will be harder than 883 and lets say also Swarovski 95 (or 115)?
Regards, Juhani
Unfortunately my recent TSN-99A experience mirrors many others here. At higher mags it refused to snap into focus. At 70x it was immediately apparent that my Meopta S2 was better in contrast and apparent sharpness. Star testing - one side was consistently a bright outer ring with a blurry fog interior, the other side at times seemed very good with concentric rings, but at other times seemed to show some astigmatism and a wee bit of triangle at 3-4 rings.
A year ago I compared an ATX95, 883 and S2. At 60x the 883 was very slightly sharper than the S2 and was noticeably clearer under low light conditions. In comparison I was expecting better from the 99A, however it's performance was very disappointing. On the plus side I really like the 2 screw plate mounting ability. Very solid.
A year ago I compared an ATX95, 883 and S2. At 60x the 883 was very slightly sharper than the S2 and was noticeably clearer under low light conditions. In comparison I was expecting better from the 99A, however it's performance was very disappointing. On the plus side I really like the 2 screw plate mounting ability. Very solid.
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Juhani,
I don't remember the exact number, but by now I have probably seen 6-8 Kowa 99A's. Of these, Three have been very good to excellent and at least a couple pretty poor. I'm sorry I cannot be more clear than this, but that's because only one of them I've had home for any length of a time, and the poor ones I did not spend much time on as I was mostly interested in finding good ones.
So my sampling actually gives a bit better picture of the quality spread than what you or Henry have seen, but if we take all this together plus a couple of other user reports and also Jan Meijerink placing his sample of the 99 in the middle of his sample variation spread curve for the 883 on his visual resolving power chart, we must conclude that at least the early production runs of the 99 have left quite bit to be desired.
Tmathews's pictures above, although they are not taken very close to focus, nevertheless show a scope which I would guess comes much closer to the very good-excellent samples I have seen. There is still a fair bit of SA in them, but otherwise the images look clean and there is a proper central spot on both sides of focus. You can also see the peculiar and very good CA characteristics here: there is this dark amber outer ring in the inside-focus picture, and very little colour spilling anywhere else.
At this point I think that there is potential in the design for being the best scope available at the moment, but only a small minority of produced units deliver that potential. Let's hope the production process improves.
As for the Swaros, again the quality varies. Early on, my impression was that about a half of the 95s were good to excellent but really superb samples were rare. My sense is that the rate of bad samples has been going down over the years, and that nowadays lemons are not common. Of the 115, I am yet to see a truly good sample (too much SA, variable CA - sometimes surprisingly good), but from what I've seen I think there is potential for really good ones too. I should add that I have also seen some really well corrected samples of the Zeiss Harpia 95 that work nearly as well as my cherry ATX 95 at their max 70x mag.
The Meopta that Bill has is really good with apparently consistent quality, but unfortunately it gives up so much in aperture that it is not able to compete for maximum resolution. Same goes for the Nikon Monarch.
- Kimmo
I don't remember the exact number, but by now I have probably seen 6-8 Kowa 99A's. Of these, Three have been very good to excellent and at least a couple pretty poor. I'm sorry I cannot be more clear than this, but that's because only one of them I've had home for any length of a time, and the poor ones I did not spend much time on as I was mostly interested in finding good ones.
So my sampling actually gives a bit better picture of the quality spread than what you or Henry have seen, but if we take all this together plus a couple of other user reports and also Jan Meijerink placing his sample of the 99 in the middle of his sample variation spread curve for the 883 on his visual resolving power chart, we must conclude that at least the early production runs of the 99 have left quite bit to be desired.
Tmathews's pictures above, although they are not taken very close to focus, nevertheless show a scope which I would guess comes much closer to the very good-excellent samples I have seen. There is still a fair bit of SA in them, but otherwise the images look clean and there is a proper central spot on both sides of focus. You can also see the peculiar and very good CA characteristics here: there is this dark amber outer ring in the inside-focus picture, and very little colour spilling anywhere else.
At this point I think that there is potential in the design for being the best scope available at the moment, but only a small minority of produced units deliver that potential. Let's hope the production process improves.
As for the Swaros, again the quality varies. Early on, my impression was that about a half of the 95s were good to excellent but really superb samples were rare. My sense is that the rate of bad samples has been going down over the years, and that nowadays lemons are not common. Of the 115, I am yet to see a truly good sample (too much SA, variable CA - sometimes surprisingly good), but from what I've seen I think there is potential for really good ones too. I should add that I have also seen some really well corrected samples of the Zeiss Harpia 95 that work nearly as well as my cherry ATX 95 at their max 70x mag.
The Meopta that Bill has is really good with apparently consistent quality, but unfortunately it gives up so much in aperture that it is not able to compete for maximum resolution. Same goes for the Nikon Monarch.
- Kimmo
I have discussed with a friend why Kowa may be having problems with the Kowa 99.
I thought that fluorite crystal is the same throughout the blank.
Apparently it is fused, so that striations are possible.
Maybe larger sizes have more problems.
Another reason is that Kowa's old timers may have retired or passed away.
The new workers may just not know the small details and tricks that those before knew.
Companies can lose their way over time because experience is lost.
Hopefully, in time, the Kowa 99 will improve in quality.
Regards,
B.
I thought that fluorite crystal is the same throughout the blank.
Apparently it is fused, so that striations are possible.
Maybe larger sizes have more problems.
Another reason is that Kowa's old timers may have retired or passed away.
The new workers may just not know the small details and tricks that those before knew.
Companies can lose their way over time because experience is lost.
Hopefully, in time, the Kowa 99 will improve in quality.
Regards,
B.
My Meopta S2 star test views are much like the ones in Tmathews post 110 above, so I can't say it's perfect. But it competes very, very well against my ATX95 which seems to have excellent star test results - nice concentric rings on each side. However I'm an advanced-beginner when it comes to conducting star tests. Currently the S2 is my go-to scope, the large diameter of the ATX95 eyepiece drives results in my nose inadvertently pushing the scope around.
The S2's focus can be a bit finicky, I believe it, and the TSN-99A, would really benefit from a slower focus. The S2 is really an under appreciated scope, hopefully Meopta is cooking up an ever better S3.
The TSN-99A was returned. I tried to talk myself out of it, but the main reason I'm looking into the 99 is the ability to use the 1.6x extender, and know any 70x deficiencies will get worse at higher powers. Hopefully I can find a better version in the future.
I had one Kimmo and sold it as I intended to sell the ATX95. It did work very well, but found it cumbersome to swap in and out (as well as remember to have it on me.) May give the ATX95 another go around this spring to see if I can get over the eyepiece diameter issue. I thought using the 99A and 1.6x might be a bit easier, the 1.6x is smaller than the Swaro1.7x and easier to slip into a pocket and the eyepiece could could fit into a pocket while making the change.
I think my ultimate scope preference would be a good 883 that had a 25-70x eyepiece. Or a good 90mm scope with a built in 1.4x-1.6x Barlow.
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Hi Bill,
Out of curiosity, what's the eyepiece diameter? The Kowa has about 56 mm, I believe.
Regards,
Henning
Out of curiosity, what's the eyepiece diameter? The Kowa has about 56 mm, I believe.
Regards,
Henning
The ATX eyecup is 58mm, the housing adds another 10mm. The Kowa is a bit more than I like but I found it much better than the ATX. The S2 is only 47mm.
paperweight
Well-known member
I have been following the discussion about the TSN-99 with great interest.
After selling my 883 in October I bought a 99a about 4 weeks ago at my local dealer including the TE-80Ww. I already owned the TE-11 zoom plus two 1.6 converters.
On my 883, I had used the two converters for magnification above 100x and it worked to some extent watching moon and planets.
I found no weather situation to do a star test up to now, but will do so if I have any chance. My 883 showed some SA, but I guess my adapters DA4/DA4 plus my camera (Sony RX 100 II) might be part of the problem because, if I understand the procedure, the camera lens must be 100% the same horizontal and vertical level of the scope lens. Else there will of course be image faults whatsoever.
I did this picture of a Sparrowhawk today through a double glass pane of our garden door with the 88a, the TE 80 and a 1.6 converter. So this is 64x magnification, and this first shot is promising. Being more interested in birding than in astronomy, I feel the extra light compared to the 883 helpful with my 71-year old eyes that are slowly building a cataract.
If the star test I'm going to do is disappointing, I will look for an astronomical telescope instead of putting down my 99a.
I have already started looking around for an Astro Physics Stowaway or Traveler.
At the moment, the 99a is alternately used on a Gitzo tripod (steel) with a Gitzo G2380 head and a Berlebach Uni 16c with a Pegasus head.
To sum up my personal review: I like my 99a plus the TE-80 and will not return it. It's too late anyway....
After selling my 883 in October I bought a 99a about 4 weeks ago at my local dealer including the TE-80Ww. I already owned the TE-11 zoom plus two 1.6 converters.
On my 883, I had used the two converters for magnification above 100x and it worked to some extent watching moon and planets.
I found no weather situation to do a star test up to now, but will do so if I have any chance. My 883 showed some SA, but I guess my adapters DA4/DA4 plus my camera (Sony RX 100 II) might be part of the problem because, if I understand the procedure, the camera lens must be 100% the same horizontal and vertical level of the scope lens. Else there will of course be image faults whatsoever.
I did this picture of a Sparrowhawk today through a double glass pane of our garden door with the 88a, the TE 80 and a 1.6 converter. So this is 64x magnification, and this first shot is promising. Being more interested in birding than in astronomy, I feel the extra light compared to the 883 helpful with my 71-year old eyes that are slowly building a cataract.
If the star test I'm going to do is disappointing, I will look for an astronomical telescope instead of putting down my 99a.
I have already started looking around for an Astro Physics Stowaway or Traveler.
At the moment, the 99a is alternately used on a Gitzo tripod (steel) with a Gitzo G2380 head and a Berlebach Uni 16c with a Pegasus head.
To sum up my personal review: I like my 99a plus the TE-80 and will not return it. It's too late anyway....
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