Dennis ...... Nice summary of the Nikon Monarch HG 8X42. I have had mine now for a couple of months and am quite happy with it. I agree with most of what you observed with just a few exceptions.
What makes this binocular stand out among other models in the same class are the exceptional wide FOV and the light weight and handling for a 42mm. You also made note of those features. I suspect it did remind you to some degree of your prior Swaro EL SV 8X32. You have mentioned previously of your desire for the smaller lighter size of a 32mm as compared to a 42mm. The HG is a lot closer to those attributes of your old 32mm than other 42mm models.
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.....But as Chill 4x4 said they are no Zeiss SF or Swarovski SV when it comes to a flat field and sharp edges. I am surprised Nikon advertises them as having sharp edges because in my opinion they do not. So it takes away from any WOW factor. There is quite a bit of fall off in sharpness at the edges unlike the SV, SF or Canon 10x42 IS-L which are tack sharp to the edge.....
You and Chuck are right about the HG not being sharp to the edge. Some other members have observed the same. I do not understand why Nikon says the following:
"Nikon’s Field Flattener Lens System - Works in conjunction with MONARCH HG’s extraordinarily wide field of view* —8.3° and 6.9° respectively in the 8x42 and 10x42 models—to provide a sharp, clear view to the lens periphery."
My guess is Nikon wanted a larger center view than that of the Monarch 7 but did not want to infringe on the flat view of the EDG so they held back to some degree in the HG. It is a very nice compromise.
There is noticeable fall of in sharpness closer to the edge compared to a flat field model such as the Zeiss SF, Nikon EDG or Canon 10X42 L IS, but not compared to a classic design, such as a Tract Toric or Zeiss Conquest, that does not use lens flatteners. Realistically, the HG should be classified with and compared to classic designs rather than flat field models even though Nikon promotes the HG as a flat field binocular.
When compared to classic models, the 8X42 HG has a very large center view. I compared it to an 8X42 Swaro SLC WB HD and they are very close with the HG maybe being ever so slightly larger. That says a lot considering the SLC is known for having a large center.
I would not say that the lack of a flat field takes away from the WOW factor as that can be a matter of personal preference. There are posts from members who do not like the flat views, saying they look unnatural. I personally like the view from a full flat field model but I am also impressed with the views from many of the classic models. I think the HG can give an impressive view, especially when considering the exceptional wide FOV.
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............ Comparing sharpness to my Canon's 10x42 IS-L's the Canon's seemed quite a bit sharper on-axis and especially at the edges. .....
There is resolution and apparent sharpness. I did not do a controlled resolution test so I do not know how that works out. I did compare to some other 8X units and the HG resolved just as well for me. The HG resolves to at least my corrected visual acuity which per a recent eye exam is "almost 20/15".
The perceived sharpness can be quite subjective. Your comparison was with an 8X vs. a 10X which complicates things even more. On the face of things, the 10X will show more detail than the 8X. That then leaves the difficult task of trying to equate the two. I found the apparent sharpness of the HG to be very good but just not quite at the level of a Zeiss SF. I did compare it to a Nikon EDG 8X32 and after careful comparison, it is just a little bit easier to pick out the fine detail with the EDG. I also compared the HG to the SLC and again, I think I was a little bit quicker picking out fine detail with the SLC.
It really needs to be compared to other binoculars in the same class. I do not have a Tract Toric 8X42 but I do have a Toric 10X42 and so I did compare the two. The power difference makes it a difficult comparison but I concentrated mainly on contrast differences and thought the HG was ever so slightly better in showing those contrasts differences. Color balance and the color of what is being viewed can influence the perception so the result can be variable. The Toric looks to have a slightly warmer color balance than the HG so that may play a part in my results. They are close enough so I think the apparent sharpness of the HG is as good as other contenders in this class.
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.......The thing that was a deal killer for me was that the eye relief was longer than the eye cups for my eye socket depth. I seem to do best with about 15mm of eye relief. The 17mm on the MHG's made the eye relief too long and I had to hold the binoculars almost a little ways about .5mm from the eye cups to avoid blackouts and I can not tolerate that. I want to put the binoculars firmly into the eyes and not have any blackouts. ......
The absolute eye relief is not the main concern when viewing without eye glasses. The real number of interest is what I think of as the "net eye relief". It is the amount of eye relief after adjusting for the length of the extended eye cup. For example, using relative numbers of 15mm for eye relief and 9mm for the length of the extended eye cup, the net eye relief would be 6mm. In another example, if the eye relief is specified as 17mm and the extended eye cup is 12mm, then the net eye relief is 5mm.
Dennis, even though you generally have had more success with a 15mm total eye relief model, in the above example, the 17mm model may work better for you because it has less net eye relief.
What counts is how long the eye cup is in relation the the total eye relief. I have a problem with several models where the eye cup is to short for the eye relief when viewing without glasses. It seems each manufacturer has their own idea what the ideal number should be.
Unlike your experience, I did not find the eye cup to be to short for the eye relief in the HG. I am not sure why you had this problem and I did not as the HG worked out better for me in this regard than many other models out there. I am curious what eye cup setting you use for the Canon 10X42 L IS. That is the only binocular I have where I have to retract the eye in one position from full extension in order to get the full FOV. Do you use it with the eye cups fully extended or do you retract it one stop or more stops?
Just a couple of things come to mind that could be a cause of the results you had. Are you sure you had the eye cups of the HG fully extended? There are four positions. Full retraction, two intermediate stops, and fully extended. A second possibility is the IPD setting was off somewhat. Your experience is not what I would have expected with the HG but I am at a loss to explain it.
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......If you are used to an SF of SV these are going to disappoint. They are not up to that level. .....
Having a Zeiss SF 8X42, I think it is the finest binocular I have ever used. Even so, the Nikon HG is not a disappointment. Actually, it is quite impressive. The SF is better optically but the HG is still very good and the differences are not huge. There are times that I go for the HG when looking for the smaller size and lighter weight and I am not giving up a lot optically. The FOV of the HG is larger than most, the view is bright with a nice contrast and center view is also larger than most. Given a choice between the two, I would easily choose the SF but I would not be disappointed with the HG.
What would be interesting to hear is how you think the Nikon Monarch 8X42 HG compares to your Tract Toric 8X42. Unless you can find a resolution to the eye cup length issue you experienced, the HG would not be a contender for you, but assuming they were the same in that regard, how do they compare?
I have compared the 8X42 HG to my Tract Toric 10X42. Based on what I have read, I am assuming the 8X42 and 10X42 Toric are very similar other than magnification and apparent FOV. Based on what I have experienced and making mental adjustments for the differences in the specs between the two Torics, I would go with the HG due to the large FOV, the smaller size and lighter weight and what I think would be ever so better contrast.