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Some 16x70s- APM MS ED 16x70 compared with Fuji FMT and Lunt MS

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#26 Gordon Rayner

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Posted 11 November 2017 - 04:20 PM

RE:  # 21, divergent fields of view

 

Are the Fuji   aligned via  eccentrics  around  the objectives ?

 

That was the case in the 10 x 70  of  20 years ago.   I have not worked on any of the newer body styles, nor any of their 16 x 70.    Nor have I worked on any of the  Kunming/APM. 

 

The Chinese from APM/ Lunt   are aligned via  prism plate tilting , no?  Or via  individual prism tilts,  or via  individual  prism  sliding  laterally?

 

Perhaps  the divergent fields of view  are the result of  overuse of the  prism adjustments, to achieve  axial image alignment, or "collimation" ( if you must).   If that is the case, then  the solution will be to tighten prism angle  tolerances   and/or    mechanical tolerances.    A reading of Hanna in ATM II or III, op. cit. many times,  may clarify. 



#27 jrbarnett

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Posted 11 November 2017 - 04:41 PM

RE:  # 21, divergent fields of view

 

Are the Fuji   aligned via  eccentrics  around  the objectives ?

 

That was the case in the 10 x 70  of  20 years ago.   I have not worked on any of the newer body styles, nor any of their 16 x 70.    Nor have I worked on any of the  Kunming/APM. 

 

The Chinese from APM/ Lunt   are aligned via  prism plate tilting , no?  Or via  individual prism tilts,  or via  individual  prism  sliding  laterally?

 

Perhaps  the divergent fields of view  are the result of  overuse of the  prism adjustments, to achieve  axial image alignment, or "collimation" ( if you must).   If that is the case, then  the solution will be to tighten prism angle  tolerances   and/or    mechanical tolerances.    A reading of Hanna in ATM II or III, op. cit. many times,  may clarify. 

As in conditionally collimated rather than actually collimated?

 

Best,

 

Jim



#28 Gordon Rayner

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Posted 11 November 2017 - 05:24 PM

No,   my first thought is  that   the effect which Rich V  described above  would not be directly, first order, related to  the presence or absence  of parallelism  of exiting axial rays  from each of thetwo eyepieces , to the hinge axis,  at all interpupillary distances .  Three- axis parallelism,  that is.  "collimation"  in one popular sense of that word. 
 
IIRC,   prism  plate tilting   is tolerable  in small amounts.  But  overused,  it can result in the effects which  Rich V   describes.   
 
A related  criterion  is that the nodes of the objective lense(s)  and of the eyepiece lenses  should lie  on the  same line.(  collimation in the primary, fundamental sense of the word)  Achievement of that, together with simultaneous   3-axis  parallelism, implies  that good mechanical and optical tolerances and positioning   be  maintained.
 
The   defective objectives which JCB   describes   could be related?  Defective centering  or mounting  of  elements?  Or in the eyepieces'  elements  individually and/or in relation to the other elements ?

Edited by Gordon Rayner, 12 November 2017 - 05:14 PM.


#29 Rich V.

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Posted 11 November 2017 - 06:17 PM

Good timing, Gordon.   wink.gif   A follow up on the APMs; as I pointed out above, the primary issue in my sample was the non-overlapping FOVs which I find bothersome.  

 

As it turned out, when I notified Markus that I had an issue regarding the overlap of the FOVs, he was in China making a visit to KUO, the mfgr. of these binos.  He looked through samples at the factory and saw what I saw.  KUO explained that they actually adjust their big binoculars with an amount of FOV divergence built in as they claim it increases viewing comfort at closer distances. They said that this compromise is made because these binoculars is not just marketed for astronomy use.

 

At the factory, Markus tried comparing different divergence values and an agreement was made to decrease the amount of divergence by about half since the MS is marketed by him primarily as an astro binocular.  He recommended I should try adjusting this myself and see if I could achieve a greater level of overlap that I could be more comfortable with.

 

I was a bit hesitant at first as I've gone down the "conditional alignment" rabbit hole before when dealing with prism tilt screws that others had "adjusted" beforehand.  Sometimes the prisms can really get messed up.  I was afraid I might end up with a worse outcome, particularly since the merging of stars was good despite the field overlap issue. 

 

Today I bit the bullet and decided I had nothing to lose so I set up to perform a daylight prism tilt adjustment.  These KUO made binos use a tilting prism plate rather than eccentric objectives like the Fujis.  They use the now common two screws per prism arrangement.  Each screw tilts the prisms 90° in relation to the other.  I used a white cross on a mountaintop about a mile away against a blue sky as an alignment  target.  With careful incremental adjustments of both sides, making pencil witness marks and directional notes, I was able to cut the level of divergence of the FOVs to less than half the previous amount while still getting a good merge of the images of the cross.  Swinging the binos through narrower IPDs (I'm at 71mm), as best I could evaluate, shows I didn't stray too far off of true collimation with just a bit of misalignment at the very narrowest IPDs.  Tonight I'll try fine tuning the alignment on a point source target at even greater distance to get it as good as possible.

 

I don't really understand KUO's design philosophy here but I'm glad to see I've got the overlap of FOVs close enough that it doesn't bother me as it did before. I'd think most of us have a preference for one unified, round FOV or at least very close to that.  Hopefully, current production of these MS binos will be better suited to our tastes as astro binos as nobody I know wants to modify the alignment of a new binocular. 

 

Rich


Edited by Rich V., 11 November 2017 - 06:25 PM.

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#30 Rich V.

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Posted 11 November 2017 - 07:28 PM

 

wow some incredibly useful info there. Thanks Rich.

 

It seems very much like the Fujis are somewhat outdated now - still a great bino but things have moved on. The APMs sound incredible optically.

 

Slightly disappointing to hear about the divergence issue, like you I would expect a perfectly circular FOV as well as collimation, I'm not sure I could live with that long term. Your other comments re. the eyepieces seem to back up my suspicion that Chinese mechanical construction is not yet quite at the level of the good Japanese stuff.

 

thanks for a very interesting review.

It is very interesting.  My perception is that the Japanese are in the process of abandoning the Porro market wholesale on account of declining market segment spend.  The high margin part of the binocular market has shifted to roof prism designs.  The innovation/R&D that is happening in binoculars in Japan seems to be happening places other than Porros.  Other indicia include Nikon and Fuji cancelling certain Porro models entirely or limiting their continued sale to the home market.

 

The Chinese have moved in to fight over the abandoned niche and will use commoditization tactics to divvy up the marketshare.  They have borrowed innovations from the still-evolving roof prism high end of the market - utilization of nicer, complex, LER, wide field eyepieces, low dispersion glass in objectives, etc.  Many top level Japanese and European roof designs use multiple ED elements in the objectives in fact.

 

So in a way the situation is bittersweet.  The writing for Porros is on the wall.  On the sweet side, you will get some innovation in the form of borrowing from adjacent segments, which has resulted in some very nice designs.  On the bitter side, though, when firms compete in a rapidly commoditizing segment, they largely compete on price.  Such segments are characterized by thin and thinning margins so cost control is essential.  The products are by necessity built to a price.  Hence the execution of otherwise mildly innovative designs is under continuous cost constraints.

 

I can't imagine ever needing a 10x50 binocular better than the Fuji Polaris, so I've "opted out" of chasing commoditization and hoping for value plus further innovation in that slot.  Likewise, I'm very happy with the Nikon 18x70s in the 70mm slot.  Unlike the Fujis which try and mostly succeed at delivering a balanced highly oprtimized experience (flat, corrected, immersive, wide-field, precise, rugged, durable, etc.), Nikon's designers on the 18x70s struck a different balance.  To maximize FOV and immersion at 18x, they traded some flatness and off axis correction.  Not much, but some.  What they offer instead is a very wide, slightly uncorrected field of view with a massive immersion quotient (the complex interplay between ER, AFOV, eye lens dimensions, ergonomics, etc.).  Again, I can't imagine wanting anything different in the 70mm higher magnification class.

 

It's in between that I'm looking.  I have Poseidon 10x70s which are effectively a 2 generation old design.  The current generation Porros use wide field, flattening eyepieces and low dispersion glass, the last generation used wide field eyepieces with some flattening, but no ED glass.  The two-back generation, like the Poseidons, used less wide less corrected eyepieces and no low dispersion glass.  Everything else is top drawer - build, robustness, manufacturing precision, etc. - but the design lags by a couple of generations.  Still thousands of pairs of rebranded Japanese Porros that follow this formula are turned out each year by firms like OEM manufacturing firms like GKA that follow this old formula (units like Orion's Mini Giant 9x63 and 15x63 are GKA's for example, and are very much of like-design-generation with the Poseidons).

 

I understand that I missed the boat in the 10x70/11x70 space on having anything like the 18x70s.  Apparently Nikon's original 10x70 Astroluxe prescription was more like the 18x70s - maximize FOV and immersion at the expense of a little off axis correction.  The newer (current) 10x70s are better corrected but a bit narrower in FOV, and therefore less immersive.

 

My problem is that I like my innovation but insist on execution quality too.  That has become fleeting in Porros.

 

Best,

 

Jim   

 

A thoughtful post, Jim.

 

Yes, in the 50mm and under size range, it appears that Porro binoculars are falling out of favor.  At least in the larger size range such as the 70mms, the offset Porro design still fits in nicely.  Roof prisms don't scale well into the larger objective sizes unless rhomb turrets are added for IPD adjustment as used by roof prism BTs . Fuji and Nikon have been putting out essentially the same large Porro binoculars for years now; Fuji was somehow able to keep the price of the FMTs down at a surprisingly low level for many years.  I purchased my FMTs from Kevin B. around 15 yrs ago for $620. and the price stayed at around that level rising only recently when they finally "caught up" and decided to bring the pricing up closer to the Nikon offering.

 

Now, the APMs have filled the $600.-700. niche vacated by the Fujis.  They clearly have made some major improvements to the old formula; providing double the usable eye relief to the flat field eyepiece design, which IMO, is the biggest downside of the Fujis.  The addition of ED doublet objectives really cleans up the views of bright objects and for daytime use; I don't know why that didn't happen earlier.   My WO 22x70s still have superior color correction but they were limited production binos using longer focal length telescope objectives and are quite massive for their aperture.  They could really use the LER FF eyepieces of the MS EDs, though, as eye relief of their BA8 eyepieces suffers like the Fujis.

 

Some compromises have been made production wise with the newer KUO offerings to make pricing competitive.  They are similar in mechanical build to the Japanese big binos of yesteryear (think Vixen giants of the '90s)) but are clearly optically superior.  I wonder if the market, which is so price conscious these days, is willing to pay that extra amount that would put them as mechanical equals to the Fuji or Nikon offerings.

 

As you age, Jim, you may find the LER FF eyepieces of the APMs to be irresistible.  I know that's my favorite feature of these binos and Fuji and Nikon can't touch that at present.   wink.gif

 

Rich


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#31 Gordon Rayner

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Posted 11 November 2017 - 08:37 PM

I have several WW II Naval Gun Factory 9 x 63 with B&L Mk 21 or Mk1 bodies. One was acquired in a trade more recent.
than the others.

It was adjusted by someone for zero up-down error (step) on infinity targets at 65mm. IPD, which happens to be my intereye space. So, I have
not adjusted it into 3-axis parallelism. There is a remaining horizontal error, which forces the eyes to look inward, as in reading a book, for infinity use.
3- axis parallelization would involve WW II sealant softening, a cleanup of the old sealant with xylene or toluene ( in short supply) and other activity which would probably consume most of a day, at least.

The situation described above, in #29, forces the eyeballs to rotate outward with respect to each other. That seems a very misguided policy by KUO. Such eyeball divergence is uncomfortable for me and for nearly(all?) others.

Can we attribute the lack of field overlap described by RichV to the choice of prism tilting as the adjustment method for target image superposition at some distance (hopefully infinity)?

I do not know if current Fuji or Nikon top grade 70mm. Porro binoculars use eccentrics around the objectives. They did in the past.

Can one conclude that dependence upon other than very small prism tilts is an undesirable shortcut to avoid the precise fits needed for quality eccentrics around the objectives?

Edited by Gordon Rayner, 12 November 2017 - 05:57 PM.

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#32 jrbarnett

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Posted 11 November 2017 - 11:12 PM

 

 

wow some incredibly useful info there. Thanks Rich.

 

It seems very much like the Fujis are somewhat outdated now - still a great bino but things have moved on. The APMs sound incredible optically.

 

Slightly disappointing to hear about the divergence issue, like you I would expect a perfectly circular FOV as well as collimation, I'm not sure I could live with that long term. Your other comments re. the eyepieces seem to back up my suspicion that Chinese mechanical construction is not yet quite at the level of the good Japanese stuff.

 

thanks for a very interesting review.

It is very interesting.  My perception is that the Japanese are in the process of abandoning the Porro market wholesale on account of declining market segment spend.  The high margin part of the binocular market has shifted to roof prism designs.  The innovation/R&D that is happening in binoculars in Japan seems to be happening places other than Porros.  Other indicia include Nikon and Fuji cancelling certain Porro models entirely or limiting their continued sale to the home market.

 

The Chinese have moved in to fight over the abandoned niche and will use commoditization tactics to divvy up the marketshare.  They have borrowed innovations from the still-evolving roof prism high end of the market - utilization of nicer, complex, LER, wide field eyepieces, low dispersion glass in objectives, etc.  Many top level Japanese and European roof designs use multiple ED elements in the objectives in fact.

 

So in a way the situation is bittersweet.  The writing for Porros is on the wall.  On the sweet side, you will get some innovation in the form of borrowing from adjacent segments, which has resulted in some very nice designs.  On the bitter side, though, when firms compete in a rapidly commoditizing segment, they largely compete on price.  Such segments are characterized by thin and thinning margins so cost control is essential.  The products are by necessity built to a price.  Hence the execution of otherwise mildly innovative designs is under continuous cost constraints.

 

I can't imagine ever needing a 10x50 binocular better than the Fuji Polaris, so I've "opted out" of chasing commoditization and hoping for value plus further innovation in that slot.  Likewise, I'm very happy with the Nikon 18x70s in the 70mm slot.  Unlike the Fujis which try and mostly succeed at delivering a balanced highly oprtimized experience (flat, corrected, immersive, wide-field, precise, rugged, durable, etc.), Nikon's designers on the 18x70s struck a different balance.  To maximize FOV and immersion at 18x, they traded some flatness and off axis correction.  Not much, but some.  What they offer instead is a very wide, slightly uncorrected field of view with a massive immersion quotient (the complex interplay between ER, AFOV, eye lens dimensions, ergonomics, etc.).  Again, I can't imagine wanting anything different in the 70mm higher magnification class.

 

It's in between that I'm looking.  I have Poseidon 10x70s which are effectively a 2 generation old design.  The current generation Porros use wide field, flattening eyepieces and low dispersion glass, the last generation used wide field eyepieces with some flattening, but no ED glass.  The two-back generation, like the Poseidons, used less wide less corrected eyepieces and no low dispersion glass.  Everything else is top drawer - build, robustness, manufacturing precision, etc. - but the design lags by a couple of generations.  Still thousands of pairs of rebranded Japanese Porros that follow this formula are turned out each year by firms like OEM manufacturing firms like GKA that follow this old formula (units like Orion's Mini Giant 9x63 and 15x63 are GKA's for example, and are very much of like-design-generation with the Poseidons).

 

I understand that I missed the boat in the 10x70/11x70 space on having anything like the 18x70s.  Apparently Nikon's original 10x70 Astroluxe prescription was more like the 18x70s - maximize FOV and immersion at the expense of a little off axis correction.  The newer (current) 10x70s are better corrected but a bit narrower in FOV, and therefore less immersive.

 

My problem is that I like my innovation but insist on execution quality too.  That has become fleeting in Porros.

 

Best,

 

Jim   

 

A thoughtful post, Jim.

 

Yes, in the 50mm and under size range, it appears that Porro binoculars are falling out of favor.  At least in the larger size range such as the 70mms, the offset Porro design still fits in nicely.  Roof prisms don't scale well into the larger objective sizes unless rhomb turrets are added for IPD adjustment as used by roof prism BTs . Fuji and Nikon have been putting out essentially the same large Porro binoculars for years now; Fuji was somehow able to keep the price of the FMTs down at a surprisingly low level for many years.  I purchased my FMTs from Kevin B. around 15 yrs ago for $620. and the price stayed at around that level rising only recently when they finally "caught up" and decided to bring the pricing up closer to the Nikon offering.

 

Now, the APMs have filled the $600.-700. niche vacated by the Fujis.  They clearly have made some major improvements to the old formula; providing double the usable eye relief to the flat field eyepiece design, which IMO, is the biggest downside of the Fujis.  The addition of ED doublet objectives really cleans up the views of bright objects and for daytime use; I don't know why that didn't happen earlier.   My WO 22x70s still have superior color correction but they were limited production binos using longer focal length telescope objectives and are quite massive for their aperture.  They could really use the LER FF eyepieces of the MS EDs, though, as eye relief of their BA8 eyepieces suffers like the Fujis.

 

Some compromises have been made production wise with the newer KUO offerings to make pricing competitive.  They are similar in mechanical build to the Japanese big binos of yesteryear (think Vixen giants of the '90s)) but are clearly optically superior.  I wonder if the market, which is so price conscious these days, is willing to pay that extra amount that would put them as mechanical equals to the Fuji or Nikon offerings.

 

As you age, Jim, you may find the LER FF eyepieces of the APMs to be irresistible.  I know that's my favorite feature of these binos and Fuji and Nikon can't touch that at present.   wink.gif

 

Rich

 

It's worth noting that the home market price of most Fujis and all Nikons is *much* lower than the US price.  I've noted only one major exception:  the 10x70 Poseidon price here ($518) is lower than the Japan price for that same binocular.  Oddly in Japan the Poseidon is very close in price to the Polaris - implying that the fancier eyepieces aren't that much more costly to spec.  Japan 10x70 Poseidon MT price = $550; Japan 10x70 Polaris FMT price = $670.  Compare that to the current US 10x70 FMT price, $950.  The 16x70s similarly are much less in the home market; $790 vs. $1050.  

 

Nikon pricing is similar in the home versus export market delta:

 

Nikon Model; US street price; Japan street price

 

10x70 Astroluxe; $1440; $944

7x50 Prostar; $980; $670

18x70 Astroluxe; $1500 ;$1000

 

Given that Fuji and Nikon presumably are making a profit on these at the Japan market price, that hints at how much margin (a lot) must be in the KUO units at current retail pricing without the high costs of Japanese skilled labor and manufacturing.

 

It seems really strange that Fuji and Nikon responded to declining demand not by doing what you normally do if you have margin - lower the price - but rather by significantly raising prices.  As price goes up, demand goes down.  If dwindling volume is your problem in a market, upping prices can only make that particular problem worse.  It's puzzling.

 

Best,

 

Jim



#33 Riccardo_italy

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Posted 12 November 2017 - 08:24 AM

It seems really strange that Fuji and Nikon responded to declining demand not by doing what you normally do if you have margin - lower the price - but rather by significantly raising prices.

 

If you have market power, you may prefer lower sales but with a greater profit per unit sold.

Remind: with perfect competition, price is low but profits are zero :)

 

Thanks to everybody, this is a beautiful discussion. I hope and I suggest some moderator may pin it in the "Gems: *BEST OF Binocular Forum" pinned topic.


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#34 shrike3612

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Posted 12 November 2017 - 10:24 AM

Thank you for photos.

It is good binoculars I think.

 

Also It has a nice tirpod adapter.



#35 Rich V.

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Posted 12 November 2017 - 07:11 PM

"Also It has a nice tripod adapter."

 

I like it and think it is a big improvement over the old arrangement on the MS with a recessed 1/4"-20 hole only.  You get more options, which is good.   smile.gif

 

I twisted the adapter onto the threaded hub tight enough that the set screw provided isn't necessary.  There are three holes provided around the adapter rod for placing the set screw but the idea of twisting a screw into the hub's threads didn't appeal to me.  The adapter rod on the hinge can be left in place if hand held or while in the case and the upright axis/QR plate just slides off the end.  That's a removable knob at the end of the adapter so the binocular can't slide off accidentally. 

 

It allows smooth movement in the roll axis by setting the tension with the knob at the top.  The roll axis is a help if using a p-gram with a hinge.

 

Rich



#36 Rich V.

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Posted 12 November 2017 - 08:23 PM

The situation described above, in #29, forces the eyeballs to rotate outward with respect to each other. That seems a very misguided policy by KUO. Such eyeball divergence is uncomfortable for me and for nearly(all?) others.

Can we attribute the lack of field overlap described by RichV to the choice of prism tilting as the adjustment method for target image superposition at some distance (hopefully infinity)?

I do not know if current Fuji or Nikon top grade 70mm. Porro binoculars use eccentrics around the objectives. They did in the past.

Can one conclude that dependence upon other than very small prism tilts is an undesirable shortcut to avoid the precise fits needed for quality eccentrics around the objectives?

Gordon, it's not that the eyeballs aren't looking straight forward, parallel, they are.  The images are aligned so there's no eye strain from forced divergence. The fields appear to diverge but not the optical axes; they're aligned, at least at my eyepoint.  It seemed to be collimated throughout an IPD range that I could compare by eyeball. No merging problems at all.

 

It gives the impression that the axes diverge if you judge that by concentricity of FOVs but the lines of sight are still parallel/collimated by prism tilt.  There seems to be a number of tilt solutions that can reach a comfortable, merged view with changing amounts of FOV overlap. 

 

The prism design used on the MS appears to be similar to the previous BA8 models. I like the tilt screws location in the faces of the prism covers, unlike the older KUO designs from the early 2000s that had tiny, soft tilt screws buried under the coverings on the sides of the prism housings. 

 

I'm glad that the overlap issue was able to be "adjusted out" but I wish I could picture it better. I would be logical to think that the least amount of prism tilt necessary to achieve parallelism would be the ideal starting point but I don't know the steps of the procedure being used. The workings of this alignment method would surely become much more clear if a collimator was employed for analysis rather than eyeballs.  wink.gif

 

BTW, I'm pretty confident the current premium Fujis and Nikons still use eccentrics.  

 

Rich 



#37 RichD

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Posted 13 November 2017 - 10:17 AM

Yes the FMT line and Astroluxe are still eccentric ring collimated.

 

Fujinon's pricing structure does indeed seem to be totally illogical - the 16x70 FMT is over 1000UKP here new.



#38 Uwe Pilz

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Posted 14 November 2017 - 12:31 AM

> The high margin part of the binocular market has shifted to roof prism designs.

 

That is the case, indeed. But keep in mind that there is a limit of maximum aperture with the roof prism construction. If the front lenses are bigger than the interpupillary distance you cannot use them anymore, at least not with two eyes ^^. Usual, the biggest aperture made in roof prism is 56 mm.

 

70 mm is close to 56 mm, so they which may be cover the same market segment. But if you come to 80 mm or more, every producer has to use porro prisms. I see no reason why well-respected producers should leave this segment.


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#39 hallelujah

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Posted 14 November 2017 - 12:42 AM

But keep in mind that there is a limit of maximum aperture with the roof prism construction.

Usual, the biggest aperture made in roof prism is 56 mm.

The discontinued Fujinon HB binocular is 60mm. (59.65mm)

 

http://www.company7....ocs/1560hb.html

 

The discontinued Minox BD15x58 BR ED also comes to mind.

 

https://www.allbinos...ifications.html

 

Stan


Edited by hallelujah, 14 November 2017 - 12:48 AM.


#40 Uwe Pilz

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Posted 14 November 2017 - 12:49 AM

 

Thanks to everybody, this is a beautiful discussion. I hope and I suggest some moderator may pin it in the "Gems: *BEST OF Binocular Forum" pinned topic.

 

The thread is archived and cannot be edited anymore (not even with moderator rights).

 

I added it to the Links of interest thread.



#41 Rich V.

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Posted 16 November 2017 - 10:53 AM

Thanks for your efforts, Uwe.

 

Rich



#42 trener

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Posted 15 April 2019 - 04:12 PM

Well, I don't want to start a new topic so I will just chime in.

I had Lunt 16x70 binoculars and was quite happy with them. Sharp, tight stars. Could even resolve 4 stars in Orion's Trapezium, was a hard task but possible with a sturdy tripod and in very good conditions. Then APM EDs appeared on the market. Very good reviews - "better than the Lunts". I finally sold my Lunt 16x70s and bought APM 16x70 ED's in December 2018. I was stargazing three times since then, last time yesterday and.... well, I found good things - coatings are better, CA control is better, color fidelity is much better but star sharpness is very bad. I can't focus bright stars to a point, no matter how hard I try. I just can't reach proper sharpness on stars. It is hard to resolve Trapezium into two or three stars, I can't resolve Mizar binary star (13.8"), not even close. Mizar does not even look like a double star. It looks like a large blob. In my Lunts it was very easy to resolve it. Generally bright stars are astigmatic and look like blobs.

Do you have the same issues with your APM 16x70's? 

 

Sorry for my English.


Edited by trener, 15 April 2019 - 04:16 PM.


#43 Rich V.

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Posted 16 April 2019 - 09:58 AM

Well, I don't want to start a new topic so I will just chime in.

I had Lunt 16x70 binoculars and was quite happy with them. Sharp, tight stars. Could even resolve 4 stars in Orion's Trapezium, was a hard task but possible with a sturdy tripod and in very good conditions. Then APM EDs appeared on the market. Very good reviews - "better than the Lunts". I finally sold my Lunt 16x70s and bought APM 16x70 ED's in December 2018. I was stargazing three times since then, last time yesterday and.... well, I found good things - coatings are better, CA control is better, color fidelity is much better but star sharpness is very bad. I can't focus bright stars to a point, no matter how hard I try. I just can't reach proper sharpness on stars. It is hard to resolve Trapezium into two or three stars, I can't resolve Mizar binary star (13.8"), not even close. Mizar does not even look like a double star. It looks like a large blob. In my Lunts it was very easy to resolve it. Generally bright stars are astigmatic and look like blobs.

Do you have the same issues with your APM 16x70's? 

 

The MS ED binos should put up stars that look no different than your previous Lunt MS binos.  Your description of "blob" stars would indicate you clearly have a "lemon" which deserves evaluation and replacement.

 

I would certainly contact Markus at APM and point this out; this time of year it's hard to get out under the stars in many locations.  Since you now see a clear difference in resolution between the MS ED's performance on stars compared to your MS bino, that should be enough evidence that there is an issue with your particular binocular.  

 

Those of us who have evaluated the MS and MS EDs that are in proper working order can attest that they show the resolution of stars as fine points as well as other higher end Porros; that's certainly been my experience.

 

I wouldn't hesitate to resolve this with APM; you have a defective binocular and require a replacement...

 

Rich


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#44 JCB

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Posted 16 April 2019 - 05:55 PM

I had also a disappointing experience with the APM 20x70 MS ED. Obviously, one side was clearly defective, but the sharpness was not impressive on both sides, which wasn't very encouraging for that series. My venerable Fujinon 16x70 was better. I decided to return the binoculars to Markus and ask for a refund.

I would follow Rich's advice, and ask at least for a replacement, with the hope that this time you will have a decent model. There are always some lemons, in almost every brand.

Jean-Charles


Edited by JCB, 16 April 2019 - 05:57 PM.


#45 ButterFly

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Posted 17 April 2019 - 02:26 PM


Do you have the same issues with your APM 16x70's? 

.

Not at all.  The horns of Venus were well resolved last November at twilight in mine.  Venus at nght at full brightness does glare - it is just too bright.  That is to be expected.  I have resolved Mizar as well.

 

Send them back.




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