BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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It took a year, but I finally got around to purchasing the Vixen Foresta 7x50 porro CF. I just opened the box and looked across the backyard. WOW!
I really want to compare the Vixen Foresta to my Fujinon 7x50 IF. I ordered the Vixen because I wanted a second 7x50 (with center focus) for low light nature observing. The initial out-of-the-box sensation tells me the Vixen will certainly do the job.
In the days and weeks ahead I will post a few comments about my nontechnical comparison of the Vixen Foresta porro CF 7x50 with the Fujinon FMT-SX porro IF 7x50. It probably will not be the stuff of EdZ's dreams, but I will try to approach the comparison from the perspective of a leisurely twilight forest observer, as well as a back yard night sky observer.
In the meantime, as I prepare my subjective comparison--and believe me the comparison will be subjective and personal--I suggest you go to EdZ's technical review of Vixen Foresta porro CF 7x50 , which is, as to be expected, one of the Internet's finest.
Please let me know if there are some specific nontechnical comparisons you want to see reported. I make no promises. But if I can pull it off, I will report how these two 7x50s stack up. Perhaps you have personal observations about your favorite 7x50 that you want to add to this thread. Please feel welcome to post your observations.
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Bob
38°N
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 14724
Loc: Cumberland, R I , USA42N71.4W
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Your subjective comparison of the low light (dusky ish) difference in contrast. Comments on contrast are always subjective as it is very difficult for anyone to objectively measure it. Your perceptions of views would be appreciated.
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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Mary
sage
Reged: 01/29/08
Posts: 224
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I have a pair of the 7x50 Vixen Forestas and I absolutely adore them! They are an incredibly close second to my 8x42 Leica Ultravids. I really look forward to your reviews!
Mary
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ronharper
Pooh-Bah
Reged: 02/14/06
Posts: 1276
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I'm looking forward to your impressions Bob.
A triplet objective 7x50 Porro, now that's different. Sub 2 lbs, and center focus too, I thought 7x50s were supposed to hurt. Also, this is a rather costly porro, at around $300. That's just the going rate for a used FMT.
Mary's comparison is interesting, because my 8x42 Leica Trinovid, lovely and handy glass though it be, is certainly not a very close second to my 7x50 FMT, as far as pure optical performance goes. But the Ultravid is better than the older Trinovid, by all accounts. Also, EdZ gave his Vixen high marks, but didn't really shoot it out with his Prostar or WO, and doesn't own the Fujinon, as far as I know.
So, it is impossible, however hard I strain my brain, for me to deduce from this round robin/smorsgabord of information and comparisons, whether or not the Foresta will equal or beat the Fujinon. Bob, you may well be the first person in the entire universe to make this crucial comparo. The four or five of us 7x50 fans in that universe are on the edge of our seats, with beer and popcorn. Get on with it man. This ought to be good.
Ron
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Mary
sage
Reged: 01/29/08
Posts: 224
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Ron, I just love your post! I am also fortunate to have a pair of Fuji 10x70's in my arsenal, and though bigger than the 7x50 Fuji's, I have no doubts that the 7x50 Fujis are also outstanding. The great thing about the Leica 8x42 Utravids is that they are a roof and therefore, very easy to hold for long periods of time. The Vixen Foresta 7x50's are also very light and easy to hold. I once held a smaller pair of Fuji's but I'm not sure if they were the 7x50 pair, but they did seem to be heavy for their size, but still felt good in the hands.
I think anyone who has had the chance to look thru the Vixen Foresta 7x50 has really been impressed with it, especially at the price that it is. When I bought mine, they were $279 and I'm not sure if the price has gone up since then. Really a great bino for not a whole lot of money.
Mary
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F.Meiresonne
Post Laureate
Reged: 12/22/03
Posts: 3361
Loc: Eeklo,Belgium
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Quote:
I ordered the Vixen because I wanted a second 7x50 (with center focus) for low light nature observing.
Strong point. I considered once a Fujinon 10x50 as a future purchase. But because of the IF i am not so sure anymore despite the great optics....
I consider the IF on my 15x70 a good thing but on smaller bino's i am not so sure....
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Freddy Meiresonne
Obsession 18 inch #1638
Orion Optics 8 inch F/4.5 -1/8 wave optics -Vixen GP-E
20x80 Helios Stellar Binos
15x70 TS Marine (=Obie Ultra)
10x60 Helios Quantum 4(= Obie Mariner)
10x50 Helios Nature sport plus
8x40 Helios Nature sport plus
Eyepieces in use :Pan 35,24,19, N13T6, Pentax 10 XW, N9T6, Ultrascopic 7.5, TV2, baader ortho 12.5 and 9 mm
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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Tonight at twilight, I used the Vixen Foresta porro CF 7x50 to count antler points on deer visiting my backyard. When I ordered the Vixen 7x50s, I went to the local Southern States feed store and purchased a 40-lb bag of Imperial Whitetail Results deer feed. Every evening at sunset I have been dispensing four cups of deer feed (in two mounds) along the tree line behind my house. And every morning the deer feed has been gone. Tonight I observed five bucks--two 6-pointers, two 4-pointers, and one two-pointer (22 points total). No does or fawns. Guess who ate first?
This is one of the tasks the Vixen 7x50 was made to do quite well. The bright, clear, resolute view made counting antler points easy. The distance to the tree line is 30 yards. I also counted points as the band of bucks roamed a distance of 150 yards. Beyond 150 yards, the little points of the 2-pointer were not discernable in the Vixen 7x50. The slow (i.e., fine) center focus is crucial to this type of observing. The bucks move their heads frequently as they eat and forage, requiring constant focus adjustment as the points are counted. I did not use the Fujinon IF 7x50 on this twilight to count points. The Fujinon's individual focusing has made this an arduous activity in the past.
***Counting points at distances greater than 150 yards will require more magnification, such as a 15x binocular or scope.
*****Feeding deer on your own property (rural or urban) is legal in the state of Kentucky. Please check the wildlife laws in your state and community before feeding deer. This activity may not be legal in some states and communities.
. . .
Last night I did a small comparison of the Vixen with the Fujinon to observe three night sky views: Altair / Tarazed star path (Aquila)
Coathanger asterism (Vulpecula)
Circle of stars around Sadr (Cygnus). In all three views, the Fujinon FMT-SX IF 7x50 outperformed the Vixen Foresta CF 7x50. The views in the Vixen were just not as prominent as in the Fujinon. Specifically, the stars seen in the Vixen did not appear as large or shine as brightly as in the Fujinon.
The view of the Coathanger may explain. In the Vixen 7x50, star HD 182293 in the Coathanger asterism (Vulpecula), the color star on the right end (magnitude 7.1, color K-1) was very faint; observable, but faint. Star HD 182293 was more prominent in the Fujinon 7x50; still faint, but not near as faint as in the Vixen.
The same results occurred in the views of the Altair / Tarazed star path (Aquila) and the circle of stars around Sadr (Cygnus). Without a doubt, on this evening, to observe these three star patterns in the night sky, the Fujinon 7x50 takes the prize. I also noticed the Fujinon is more comfortable in my hands and against my face than the Vixen. Heavier and bigger, but more comfortable.
***My night sky is regularly 5.1 NELM. I did not measure limiting magnitude last night.
. . .
More comparisons to follow.
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Bob
38°N
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Mark9473
Post Laureate
Reged: 07/21/05
Posts: 3208
Loc: 51°N 4°E
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Interesting report, Bob. I suppose the 7x50 Foresta's would work equally well for watching the family of hedgehogs that settled in my garden, if not for the 10 m close focus distance I found listed on a Vixen website. Is this accurate? Would you be able to recommend something similar with a close focus under 3-4 meters?
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Mark
Leica 8x20; Vixen 8x42; Swift 8.5x44, 10x50 and 20x80; TS 7x50; Orion 15x63; Docter 15x60
WO Megrez II 80 FD + Baader 90° T2 Amici
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ronharper
Pooh-Bah
Reged: 02/14/06
Posts: 1276
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Mark,
When reading of your desire for a close focusing Porro, something hit me that never had, at least not so exactly. I think the search for a conventional 50mm Porro that will focus that close is doomed by geometry.
My 7x50 Fujinon's objectives are about 130mm apart at my IPD of 67mm. An object 3.5m distant, centered between the barrels, lies 1.06 degrees off the optical axis of each barrel. When magnified by 7x, this angle becomes 7.4 degrees, twice the half angle of the apparent field. At 10m, it would just barely fit into the edge of both barrels' field. So, although it would seem simple enough for a manufacturer to make eyepieces which would back way out and focus that close, the view would be prohibitively bad, or at least one-eyed, so I doubt anybody does it.
Does this make sense?
Ron
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ronharper
Pooh-Bah
Reged: 02/14/06
Posts: 1276
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Bob,
Thanks for sharing the observation. Trading off a bit of optical punch for convenience is a compromise at the heart of binocular selection, and no great evil. I still hope you will give us some kind of daytime comparison between the two 7x50s, and comment on CA and edge of field sharpness.
With apologies to those who have already sat through this little spiel, I made my IFs much more convenient to focus, by attaching a flexible metal band across the tops of the eyepieces in a kind of belt drive. Not as slick as a CF knob, but it is enough improvement to make a very powerful and relatively handy low-light tool.
HarperHyperDrive
Ron
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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I want to clarify a point in my Vixen / Fujinon comparison of the three star patterns I reported in my previous post. I am afraid if I do not make this clarification, some will think the Fujinon is better than the Vixen. And that is something I am not willing to report at this stage in the comparisons.
Let me explain.
I stated the Fujinon outperformed the Vixen in all three views. That is correct. However, that magnitude performance difference is not that significant, probably something like a 0.2 magnitude difference (and that is nothing but a guess). To quantify the difference in binocular limiting magnitude (BLM) of the two 7x50s, I probably should print some custom charts and do some comparison of BLM between the two models.
I will attempt to do so in the weeks ahead, so I can report with more certainty the BLM difference between the two 7x50s. But if the first comparison holds any weight, there is a BLM difference between the two models. But this difference is slight.
. . .
As I begin to sort out the potential comparisons between the two models, I am amazed at the possibilities. Many of the possibilities must reside in the focus arena, as focusing is probably one of the major distinctions between these two premium porro models. Another arena of comparisons must be done in the forest itself, under different leaf canopies and different light and time of day. A light meter would certainly help to quantify the light somewhat. I will see if I can borrow one for the upcoming comparisons. And still another comparison arena has to be ergonomics (weight, size, feel in the hands and against the face), as ergonomics is another distinction between these two models.
More to follow.
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Bob
38°N
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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Mark...
I did a very quick preliminary comparison on the close focus of the Vixen Foresta 7x50 porro CF. I positioned myself at a table on my patio and supported the Vixen by propping my elbows on the top of the table. Close focus came in at 5.3 meters (17.5 ft), which is similar to the advertised close focus of the Fujinon FMT-SX porro IF 7x50. This is preliminary, to be sure, and I definitely want to devote more time to testing close focus as this is certainly at variance with what Vixen is advertising (10 meters).
In the meantime, perhaps EdZ, Mary, and other Vixen owners can check the close focus of their instruments.
An alternative for viewing the hedgehog family in your garden may be something like the Leupold Katmai roof CF 6x32, with a close focus of 1.5 meters (4.9 ft). If you observe the hedgehogs during lowlight (because of the time of day or their reluctance to leave protective cover like a hedge or shrub line) it might be that magnification of the instrument may play second fiddle to close focus and brightness. Stepping down to a 6x instrument may be of some help. Of course, the Zeiss Victory roof CS 7x42 might also be a wonderful instrument to follow the antics of Mr. and Mrs. Hedgehog and their children.
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Bob
38°N
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 14724
Loc: Cumberland, R I , USA42N71.4W
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I got the Foresta at 19 feet.
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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Ron...
Thank you showing us a photo of the HarperHyperDrive. This invention certainly looks interesting.
I hope focus distinctions between the Vixen and Fujinon will be a major arena in comparing the two models. At this point, my opinion is that the Fujinon falls under the category of fast focus. As you know, the target to be observed and the time required to reach focus are two focus issues to consider. What is your opinion?
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Bob
38°N
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Mark9473
Post Laureate
Reged: 07/21/05
Posts: 3208
Loc: 51°N 4°E
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Quote:
I think the search for a conventional 50mm Porro that will focus that close is doomed by geometry.
Thanks Ron, I had figured as much. That's why I didn't explicitly ask for a porro. Perhaps something like a 7x42 roof is the way to go. Do they make any 6x36?
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Mark
Leica 8x20; Vixen 8x42; Swift 8.5x44, 10x50 and 20x80; TS 7x50; Orion 15x63; Docter 15x60
WO Megrez II 80 FD + Baader 90° T2 Amici
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 14724
Loc: Cumberland, R I , USA42N71.4W
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Quote:
To quantify the difference in binocular limiting magnitude (BLM) of the two 7x50s, I probably should print some custom charts and do some comparison of BLM between the two models.
Visit the "Best Of" threads in this forum. Follow the path to Limiting Magnitude and follow links to Charts for Cr399 (the Coathanger) and M45. You will find detailed charts marked up with star magnitudes up thru mag 12.
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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hallelujah
Carpal Tunnel
Reged: 07/14/06
Posts: 2151
Loc: Rocky Mt. High Colorado
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Quote:
Do they make any 6x36?
http://www.opticswarehouse.co.uk/proddetail.asp?prod=prodimages%2Fdeben%2520binoculars%2Fblackwatchclassic.gif&cat=363
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Celestron Traveler 8x25 & B. & H. 8x40 FC JAPAN & Revue 10x50 CF Porro FC JAPAN &
Pentax 12x50 PCF WP II FMC & Pentax 16x60 PCF WP FMC &
Pentax 20x60 PCF WP II FMC & Orion 12x63 Mini Giant FMC JAPAN &
SPECTRUM I 20x65 FC JAPAN &
Orion 15x70 Little Giant II FMC JAPAN & Orion 20x70 Little Giant II FMC JAPAN
Orion 16x80 Giant FMC JAPAN & Orion 30x80 MEGAView FMC JAPAN
Barska 30x80 X-Trail LW FC & Burgess Optical Series II 20x90 FMC
Hallelujah! For the LORD God Omnipotent Reigneth
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ronharper
Pooh-Bah
Reged: 02/14/06
Posts: 1276
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My estimate of the closest that a 50mm Porro could give a binocular view was really wrong! I came home and tried my 7x50, and although it will only focus down to about 9m, I can get the same small object in both fields, albeit very close to the edge and very much blurred, down to about 1 meter!
I found a mistake in my original calculation. I used the full objective spacing in calculating the off-axis angle, when half that value seems correct. But even that is not nearly enough to get down to what I can see. I'll keep puzzlin' over my goof, but I now think there is no good reason a Porro couldn't focus as close as any roof, if only the eyepieces would back out far enough. Sorry about that.
Ron
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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Tonight I dispense the deer feed at sunset (7:43 p.m.). However, I have to go out and do not return until 9:00 p.m. The deer feed is gone and it is quite dark outside (New Moon, heavy overcast sky). When I park my car, I go inside and grab both the Vixen and Fujinon to patrol the grounds for deer.
My first choice is the Vixen. There, 150 yards South of my driveway are three large deer eating acorns under a patch of oak trees. The Vixen reveals the shape and size of the three deer. However, there is not enough light to count antler points. I guess these are bucks--they certainly are large deer. About the size of the two 6-point deer from last night. No, I think tonight's deer might be larger?
I switch binoculars several times during the next hour. I am not using a tripod, but standing between my car and my wife's car, supporting the binoculars by propping my elbows on the car roof. The comparison tonight is to form an opinion as to which model is better, under extremely low light, at sweeping the landscape and providing a brighter view of the deer.
The landscape is pretty dark under the oak trees. With my naked eye, I can not detect any deer shapes nor can I make out the trunk of the oaks below the limb line (7-ft height above the ground). With both models of the 7x50s, the landscape comes alive. I easily discern the shape of the three deer, as well as the tree trunks and grass. But which model reveals more about the deer and their acorn dessert? It is close, very close. Not a lot of difference. However, I have to give the edge tonight to the Vixen Foresta under this cloudy moonless night.
The deer finish their acorns and walk 20 yards toward me and bed down in the grass. They are 130 yards to the South of my viewing location between the two cars. I continue to observe by switching the two models.
As time passes, I notice another important distinction between the two models. The Fujinon is designed for long vigils. The Vixen is designed for quality observation, but not conducive for long vigils. The Vixen has smaller barrels and the eyecups are hard. I find I keep pressing the Vixen deep into my eyesockets and the hard twist-up eyecups begin to ouch a little. Not so with the Fujinon. The soft rubber eyecups do not weary me at all. As time passes and I begin to switch between the models, I find myself looking forward to the large barrels and soft eyecups of the Fujinon, and dreading the hard twist-ups of the Vixen. The Fujinon design probably comes from a long line of military and marine applications where soldiers and sailors observe battle lines and coast lines for several hours at a time. Indeed, I feel part of this long vigil tradition as I observe the deer bedded in the grass.
. . .
Tonight's prize is a toss up. The Vixen gives slightly brighter views, easy focusing as the deer move around in the dark, and convenient views up to 15-20 minutes. The Fujinon, however, gives greater viewing comfort for longer observing periods (particularly when the binoculars are well supported).
For a quick walk around the grounds in low light or a binocular for a hike in a full-canopied forest, I definitely will reach for the Vixen. For a night of vigil, of observing a dark landscape, tree line, or horizon, for periods of time longer than 30 minutes and possibly as long as several hours, I will reach past the Vixen and grab the Fujinon.
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Bob
38°N
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ronharper
Pooh-Bah
Reged: 02/14/06
Posts: 1276
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Bob, that is a stunning report, typical for you, but I have to say these things just get better.
I have an old Vixen made Celestron Ultima 10x50, and the coatings look every bit as dark as on my Fujinon 7x50. Maybe the new Vixen coatings are improved since about 1985. It is great news that such a lightweight binocular could do so well. I bet ease of use helped put it on the top.
I feel eyecup comfort rather acutely when I observe leaning back in my chair, with the bino weight mostly resting on my eye sockets, and know just what you're talking about. The Fujinon 7x50 is my best there, with it's big soft squishy rubber. I guess people mostly prefer the harder modern eyecups because they are easy to adjust, and plenty comfortable for most uses, but when soft rubber fits you right, it's the best. It is, however, colder to touch in winter, if not already warmed up, than the modern plastic material. Comfort for a long spell is really important for teasing out dim objects, splitting difficult doubles, and relaxed scanning. I give my chair a lot of credit too, for helping me get into the comfortable, relaxed state in which I can see my best.
Thanks again, and also thanks to EdZ and Mary, who also gave impressive endorsements of the Vixen. The case for it is getting mighty strong.
Ron
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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Ron...
Thanks for your comments. I still have more to compare on these two premium porro 7x50s. I will continue posting in the days and weeks ahead as I do the comparisons. I also plan to report some comments on the edge sharpness and CA, as you requested.
As you indicated in one of your earlier posts, the 7x50s are no longer in the limelight as they once were. What a pity. There are so many applications for the 7x50.
There will be more later, when I get some clear skies for night sky comparisons and have time to take the Fujinon and Vixen into a full-canopied forest. I also need some time to clear some other projects from my plate.
Thanks again for your interests.
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Bob
38°N
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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Date -- Saturday, September 19, 2009
Time -- 9:30 p.m.
Conditions
Partly cloudy -- 50% of sky covered
Transparency -- ???
Seeing -- Average 3/5
Temperature -- 71° F
Humidity -- 68%
Dew point -- 60° F
Wind speed -- NE 3 mph
Visibility -- 10.00 miles
Air pressure -- 30.12"
Tonight's comparison will focus on sky background. If cloud coverage reduces, I will also try to measure binocular limiting magnitude (BLM).
. . .
The sky background appears to be brighter through the Vixen than through the Fujinon. This may explain why stars look brighter in the Fujinon. A brighter sky background reduces contrast. This is consistent with last night's landscape brightness comparison, where the Vixen presented a brighter landscape than the Fujinon. This sky background comparison is made while hand holding each model while laying on my back in a chase lounge on my patio.
Perhaps EdZ and others can explain what the brighter landscape and brighter sky background say about the Vixen. Is there more light transmission through the Vixen than through the Fujinon? Is this the effect of the Vixen's triplet objective lens? I will leave such technical questions to the optical engineers.
When observing nature or landscape during low light, the extra brightness of the Vixen seems to be a point scored for the Vixen. However, when observing stars under my normally 5.1 NELM sky (definitely not to be considered a dark sky, but darker than urban skies) the darker sky background (and greater contrast) of the Fujinon seems to be a point for the Fujinon.
. . .
A quick glance at Vega (Lyra) to compare spiking reveals the Vixen shows no spiking while the Fujinon shows some spiking. Again, this observation is made while hand holding each binocular model while laying on my back in a chase lounge on my patio. I will need to check this again, possibly several times over the upcoming weeks.
I am going to end this report at this point and go back outside. If the clouds have passed over, I will attempt a BLM measurement and write another report later tonight.
. . .
I feel I must say again, lest anyone draw any premature conclusions, both the Vixen Foresta porro CF and the Fujinon FMT-SX porro IF are premium porro binoculars. Either model would make a great addition to the observer's selection of optics. Adding both models gives the observer more opportunity to explore the many applications of the 7x50 size.
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Bob
38°N
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GlennLeDrew
Pooh-Bah
Reged: 06/18/08
Posts: 1267
Loc: Ottawa, Ontario, Canada
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Hmmm. A visibly different surface brightness of the sky when comparing two otherwise similar instruments? Wow! That would indicate a HUGE difference somewhere. I'd suggest measuring the exit pupil diameters. (I will venture that the coatings alone will not account for this.)
On to the BLM... If this were to differ between two otherwise similar binos by 0.1 magnitude (roughly 10 precent), then there must be a very significant difference between them. Even more than the numbers alone would indicate. The eye is a contrast detector, and hence effectively makes up for small differences. It will be interesting to read of your experience.
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Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Home-made Mk II RA bino, using interchangeable objectives and eyepieces
My Gallery
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
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ronharper
Pooh-Bah
Reged: 02/14/06
Posts: 1276
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Bob,
Measuring exit pupils is a good thing to do, but I would be aghast if the Fujinon isn't right on 7.1mm. (no worries, I've been aghast before) If the Vixen exit pupil was bigger, it could explain what you are seeing, but only provided your eye opens wider than 7.1mm.
It may be a difference in percentage transmission. Although a measurement of that value is tech-head central, you can easily do a comparison of the transmissions that is sensitive to a difference as small as only couple of percent or so. Just hold the binos both up to a broad uniform light source like a clear sky, and look at the exit pupils, and see if one looks brighter than the other.
Ron
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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Date -- Saturday, September 19, 2009
Time -- 11:00 p.m.
Conditions
Clear
Transparency -- ???
Seeing -- Average 3/5
Temperature -- 68° F
Humidity -- 78%
Dew point -- 59°F
Wind Speed -- Calm
Visibility -- 10.00 miles
Air pressure -- 30.13"
The focus of this comparison will be binocular limiting magnitude (BLM). This is the second comparison of the night sky observed on the evening of Saturday, September 19.
. . .
Using Chart 1: CR699 -- Brocchi's Cluster, The Coat Hanger (Zarenski, 2004, pp. 8-9) and double checked with the interactive atlas and database of SkyTools 3 (Crinklaw, 2009), there appears to be a difference of -0.04 binocular limiting magnitude (BLM) between the Vixen Foresta porro CF 7x50 and the Fujinon FMT-SX porro IF 7x50, as observed at the date, time, and conditions reported above. This comparison was made by hand holding each binocular while lying on my back in the chase lounge of my patio. No tripod was used.
Both the Vixen and the Fujinon revealed the single star HD 350042 (Magnitude: 8.63 [Tycho-2], in Vulpecula, R.A.: 19h27m04.7s, Dec.: +20°02'38"). However, only the Fujinon revealed the multiple star system HD 349993 (Magnitude: 8.67 [HIP], in Vulpecula, R.A.: 19h24m18.1s, Dec.: +20°31'51"). The Vixen failed to reveal HD 349993, a mere -0.04 BLM fainter.
Is this BLM distinction due to sky background/contrast difference between the Vixen and the Fujinon? Again, I will leave such questions to the optical engineers to answer.
Therefore, the point in this BLM comparison goes to the Fujinon. And a very slim point it is! 
. . .
I double checked spiking of Vega (Lyra). I did not notice any spiking of Vega by either binocular. This part of the comparison was measured just prior to a haze from out of the South that began to affect the bright stars in the South-Western night sky. I first noticed that the haze began to affect the planet Jupiter, and then the bright stars of the Summer Triangle -- Altair (Aquila), Deneb (Cygnus), and Vega (Lyra). I did not notice any hazing of the bright stars during the BLM portion of the comparison. In any event, I certainly need to repeat the BLM comparison to eliminate any difference due to hazing. I will try to repeat the BLM comparison with a tripod on another night.
. . .
REFERENCES
Crinklaw, G. (2009). Skytools 3 pro edition. [Observation planning software, ver. 3.0d.]. Cloudcroft, NM: Skyhound.
Zarenski, E. (2004). Limiting magnitude in binoculars: Methods used for determining BLM, testing results of some common binoculars, and conclusions based on field observations. Cloudy Nights Telescope Reviews. Retrieved September 19, 2009, from
http://www.cloudynights.com/documents/limiting.pdf
--------------------
Bob
38°N
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 14724
Loc: Cumberland, R I , USA42N71.4W
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it would be impossible to establish that one has a 0.04 difference in BLM over the other. These would be considered equal.
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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EdZ...
Thanks for the clarification on the 0.04 BLM difference. 
. . .
Everyone, if you are interested in BLM, please go to EdZ's report, which is GREAT! The link to his BLM report is in the REFERENCES of my previous post.
EdZ, once again, thank you for sharing your knowledge and skill with the rest of us. You are one in a million.
--------------------
Bob
38°N
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KennyJ
Reged: 04/27/03
Posts: 12889
Loc: Lancashire UK
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Bob ,
I've been following this thread with interest .
Just a note -- I think EdZ deserves to have his surname Zarenski spelled correctly in your references ! :-)
Kenny
--------------------
If everyone is thinking the same thing , no-one is thinking - General George S.Patton
Zeiss 7 x 42 BGAT
Captain's Helmsman 7 x 50
Nikon 10 x 42 Superior E
Swift Audubon Kestrel 10 x 50
Helios 15 x 70 Observation
Strathspey 20 x 90
Televue 76 APO
Zeiss 85 Diascope
Helios 102 f5 refractor
Various eyepieces barlows tripods mounts etc.
Panasonic Lumix DMC - TZ5 digital camera
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rookie
scholastic sledgehammer
Reged: 01/14/06
Posts: 878
Loc: St. Petersburg, FL
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Excellent report, Bob.
It's nice to read the use and eloquent application of Ed's papers by others. The Limiting Magnitude article and chart(s) have helped me quantify my observations.
I continue to be a student of this forum. I enjoy reading observing reports most and usually print them up to take them outside. I'm grateful to those of you that contribute, and of course to EdZ.
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SV
Scope: Celestron CPC8
Binoculars: Garrett GT80~45, Fujinon 16x70, Regals 10x42, Ultima 9x63, Nikon AE 8x40
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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Kenny...
Thank you for pointing out my mistake. I have corrected the spelling of EdZ's name in my REFERENCES.
A thousand pardons to our moderator Ed Zarenski.
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Bob
38°N
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 14724
Loc: Cumberland, R I , USA42N71.4W
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Thank you where thanks are due.
You are welcome where thanks are given.
edz
--------------------
Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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Date: Monday, September 21, 2009
Time: 8:00 a.m.
Conditions
Thunderstorm, heavy rain, fog/mist
Temperature -- 68° F
Humidity -- 93%
Dew point -- 66°F
Wind Speed -- South 8 MPH, Gusts 20 MPH
Visibility -- 1.00 mile
Air pressure -- 30.06"
The focus of this comparison will be observing the edge of a forest as a thunderstorm, rain, fog and mist move across the Kentucky landscape. The forest edge is a distance of 1000 yards to the SW. The observation is made from inside my living room, viewing through the front window. The Vixen is mounted on a Bogen 3001/3126 tripod/head, the Fujinon on a Manfrotto 3246/501 tripod/head.
. . .
The view through the Vixen is brighter, shows more resolution, and the natural colors of the forest paint the eyecups. The view through the Fujinon is not as bright, shows less resolution, and the colors are much too green for autumn.
As the thunderstorm passes, the rain stops, and the sky brightens--the difference between the two binoculars becomes more pronounced. The Fujinon continues to color the scene with green, while through the Vixen the natural colors of tree bark and leaves beginning to turn adds a pleasant aesthetic absent in the Fujinon. The Vixen, more than the Fujinon, reveals more detail inside the low lit forest.
Spiraling fog and mist, sometimes prevalent after a thunderstorm, twist and creep across the landscape as they float skyward. The Fujinon does a better job at penetrating the fog and mist. However, through the Vixen the thicker and brighter gray of the fog and mist add to the serenity of the morning pastoral scene. Who cares if it is Monday and there are a stack of projects to do? I am alone in the house, soaking in the forest beauty with my new Vixen Foresta binoculars.
The view of the forest edge appears above a patch of White Pines in the foreground. Drops of rain gather on the brown pine cones, collecting light and acting as little prisms. The Vixen captures the magic on the pine cones, while the magic is lost through the Fujinon among the excessive green.
This morning, the last summer morning of 2009, the Vixen Foresta earns its name--and the morning prize.
--------------------
Bob
38°N
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Wes James
Post Laureate
Reged: 04/12/06
Posts: 3453
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Bob-
If I didn't know better, I'd think you've grown quite fond of the Vixen's! A very poetic report... being married to a poet- I can appreciate that!
Wes
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Mary
sage
Reged: 01/29/08
Posts: 224
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Bob,
These are EXCELLENT reports! Your attention to detail is amazing and your latest report makes me wish I had taken the day off work to enjoy the views of nature!
Mary
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KennyJ
Reged: 04/27/03
Posts: 12889
Loc: Lancashire UK
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Bob ,
Thanks for your misty morning musings .
That report reminded me of situations a few years ago when we had a static holiday home in Wales .
There was an entrance to dense woodland on elevated ground almost exactly 1000 metres from our decking , and it was often misty around that location in the mornings .
For some reason when conditions were such , I prefered the views of it through the Helmsman 7 x 50 to that of the Zeiss 7 x 42 , and during one comparison almost exactly three years ago to the day , prefered the more natural colours and sharpness through a Nikon 50mm ED fieldscope with it's zoom lens set around 20x than the same views through my Zeiss 85mm Diascope set at 20x .
This impression of " cutting through the mist " is thus one I appreciate , although understand very little about .
I seem to recall you experimenting with various filters and spotting scopes in the daytime a while back , so perhaps in a separate thread sometime you could summarise your findings ?
Kind Regards
Kenny
--------------------
If everyone is thinking the same thing , no-one is thinking - General George S.Patton
Zeiss 7 x 42 BGAT
Captain's Helmsman 7 x 50
Nikon 10 x 42 Superior E
Swift Audubon Kestrel 10 x 50
Helios 15 x 70 Observation
Strathspey 20 x 90
Televue 76 APO
Zeiss 85 Diascope
Helios 102 f5 refractor
Various eyepieces barlows tripods mounts etc.
Panasonic Lumix DMC - TZ5 digital camera
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Mark9473
Post Laureate
Reged: 07/21/05
Posts: 3208
Loc: 51°N 4°E
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Quote:
The view through the Vixen is brighter, shows more resolution, and the natural colors of the forest paint the eyecups. The view through the Fujinon is not as bright, shows less resolution, and the colors are much too green for autumn.
I'm not surprised that two binoculars would have a different wavelength position for their peak transmission, but I am surprised it results in such a clear difference. The Fujinon is better at night, the Vixen by day.
--------------------
Mark
Leica 8x20; Vixen 8x42; Swift 8.5x44, 10x50 and 20x80; TS 7x50; Orion 15x63; Docter 15x60
WO Megrez II 80 FD + Baader 90° T2 Amici
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rookie
scholastic sledgehammer
Reged: 01/14/06
Posts: 878
Loc: St. Petersburg, FL
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Beautiful writing, Bob.
--------------------
SV
Scope: Celestron CPC8
Binoculars: Garrett GT80~45, Fujinon 16x70, Regals 10x42, Ultima 9x63, Nikon AE 8x40
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hallelujah
Carpal Tunnel
Reged: 07/14/06
Posts: 2151
Loc: Rocky Mt. High Colorado
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Bob,
E X C E L L E N T !
I have not spent very much time observing outdoors, during the daytime; after reading your summary I definitely need to do some serious daytime observation.
This week is my last week of seasonal employment, so, I hope to revisit some favorite locations.
Don't stop now, keep us informed. 
Stan
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Celestron Traveler 8x25 & B. & H. 8x40 FC JAPAN & Revue 10x50 CF Porro FC JAPAN &
Pentax 12x50 PCF WP II FMC & Pentax 16x60 PCF WP FMC &
Pentax 20x60 PCF WP II FMC & Orion 12x63 Mini Giant FMC JAPAN &
SPECTRUM I 20x65 FC JAPAN &
Orion 15x70 Little Giant II FMC JAPAN & Orion 20x70 Little Giant II FMC JAPAN
Orion 16x80 Giant FMC JAPAN & Orion 30x80 MEGAView FMC JAPAN
Barska 30x80 X-Trail LW FC & Burgess Optical Series II 20x90 FMC
Hallelujah! For the LORD God Omnipotent Reigneth
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ronharper
Pooh-Bah
Reged: 02/14/06
Posts: 1276
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Bob,
My 7x50 FMT is the old style and the coatings appear simple green on every surface I can see, including prisms. You'd think that green was being reflected away preferentially, but in fact, the image tone is slightly (to my eyes) green. This is only noticeable to me on white clouds.
My 10x50 FMT (and all 10x50s in fact) however, is the new style, sometimes called SX-2, although that is not a term used by Fujinon. The coatings are very different, darker and varying in their color on the various surfaces. With the new coatings, the green cast is gone, and it looks quite unbiased to me, but some people are very sensitive, and who knows what they'd see.
A new style 7x50 might keep up with the Vixen better.
Let the trouncing continue!
Ron
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 14724
Loc: Cumberland, R I , USA42N71.4W
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Quote:
Bob,
My 7x50 FMT is the old style and the coatings appear simple green on every surface I can see, including prisms. You'd think that green was being reflected away preferentially, but in fact, the image tone is slightly (to my eyes) green. This is only noticeable to me on white clouds.
My 10x50 FMT (and all 10x50s in fact) however, is the new style, sometimes called SX-2, although that is not a term used by Fujinon. The coatings are very different, darker and varying in their color on the various surfaces. With the new coatings, the green cast is gone, and it looks quite unbiased to me, but some people are very sensitive, and who knows what they'd see.
Ron
There are several reasons why the color you see reflected off of coatings really has nothing to do with the color you see thru the binoculars.
first, good multicoatings reflect only 0.25% of the light that hits them. Even if you compounded that thru all the surfaces in a binocular,that's less than 5% of the total light, and that is not enough of a difference in spectrum to see a color change.
second, coatings are 1/4 wavelength offset from the color that they are intended to allow to pass, so the reflected color is not in parallel with the wavelength that passes.
My guess would be that color cast of a binocular is far more dependant on the spectral transmission curve of the glass, most probably primarily dependant on that of the prisms.
edz
--------------------
Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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I want to thank everyone for their kind comments on the reports. Today's regional newspaper ran a feature story on the photography of Dean Hill, which remind me of the beauty brought out by the Vixen Foresta binoculars. A photo of a mature Appalachian forest that I particularly admire is Hill's "Sit Among Giants." Here is a link to the feature story in today's newspaper -- Dean Hill's Appalachian Photography .
. . .
There are more comparisons I want to make, but those reports will have to wait a week or two.
. . .
One observation that is beginning to haunt me is fog/haze penetration. The Fujinon appears to be better at penetrating high humidity conditions on the ground. In comparing other models at different times in the past, I have noticed Nikon binoculars also appear to do quite well at haze penetration. How does haze penetration affect night sky observing? I hope others can offer comments on haze penetration.
Once again, I want to emphasize both the Vixen and the Fujinon models are premium porro binoculars and the 7x50 size is an important size. As my comparisons continue, I will try to present some of the benefits of the 7x50 size. If you have one or more 7x50 models in your selection, I hope you can take them outside and appreciate the benefits this size brings to observing.
--------------------
Bob
38°N
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hallelujah
Carpal Tunnel
Reged: 07/14/06
Posts: 2151
Loc: Rocky Mt. High Colorado
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Dean Hill's photography is incredible, thanks Bob!
--------------------
Celestron Traveler 8x25 & B. & H. 8x40 FC JAPAN & Revue 10x50 CF Porro FC JAPAN &
Pentax 12x50 PCF WP II FMC & Pentax 16x60 PCF WP FMC &
Pentax 20x60 PCF WP II FMC & Orion 12x63 Mini Giant FMC JAPAN &
SPECTRUM I 20x65 FC JAPAN &
Orion 15x70 Little Giant II FMC JAPAN & Orion 20x70 Little Giant II FMC JAPAN
Orion 16x80 Giant FMC JAPAN & Orion 30x80 MEGAView FMC JAPAN
Barska 30x80 X-Trail LW FC & Burgess Optical Series II 20x90 FMC
Hallelujah! For the LORD God Omnipotent Reigneth
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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Monday, September 28, 2009
Time: 9:45 p.m. EDT
Conditions
?? -- Sky Quality Meter
?? -- NELM
?? -- Transparency
?? -- Seeing
57°F -- Temp
42°F -- Dewpoint
?? -- Humidity
SW 7mph -- Wind
10.00 mi -- Visibility
A few clouds at 7,000 ft -- Cloud coverage
Observation
Moon at transit -- 180° azimuth, 35° altitude
Waxing gibbous with 72% of disk illuminated -- Moon phase
Day 10 -- Moon age
Moon and Jupiter 10° separation
Fujinon FMT-SX porro IF 7x50 shows a yellow ring around the Moon, with yellow rendering across the disk.
The Moon is most pleasant with the Vixen Foresta porro CF 7x50, which reveals the Moon's color close to natural as seen with my naked eye. Tonight, the Vixen view closely resembles the view through Nikon SE binoculars or an APO refractor telescope. In other words, the Vixen presents the Moon very close to perfect.
The prize tonight goes to the Vixen.
--------------------
Bob
38°N
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BobinKy
Carpal Tunnel
Reged: 04/27/07
Posts: 1683
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Tuesday, September 29, 2009
Time: 4:15 a.m. EDT
Conditions
19.54 -- Sky Quality Meter
5.1 -- NELM
Above average -- Transparency
Poor 2/5 -- Seeing
50°F -- Temp
48°F -- Wind chill
41°F -- Dewpoint
71% -- Humidity
SW 7mph -- Wind
10.00 mi -- Visibility
Clear sky -- Cloud coverage
Observation
Orion constellation
Specifically Orion's belt and M42 in Orion's Sword
Taurus constellation
Specifically Hyades (Melotte 25) and Pleides (M45)
Vixen Foresta porro CF 7x50, as with previous observations of star patterns, fails to present the stars as brightly as the Fujinon FMT-SX porro IF 7x50. Furthermore, the Fujinon shows more nebulosity around the Great Orion Nebula in Orion's Sword. Neither binocular reveals the nebulosity in the Pleiades (the veil worn by the Sisters). The jewels in the Hyades sparkle brighter in the Fujinon. In Greek mythology, the Hyades were the five daughters of Atlas and half-sisters to the Pleiades. After the death of their brother, Hyas, the weeping sisters were transformed into a cluster of stars that was afterwards associated with rain.
As a naked-eye object, the Hyades Cluster has been known since prehistoric times. It is mentioned by numerous Classical authors from Homer to Ovid. In Book 18 of the Iliad the stars of the Hyades appear along with the Pleiades, the Big Dipper, and Orion on the shield that the Hephaistos made for Achilles. I did not measure any difference in binocular limiting magnitude (BLM), but the stars in the Vixen lack the contrast displayed in the Fujinon. Again, I do not have an explanation for this difference. Perhaps it has something to do with the Fujinon's yellow rendering being better at penetrating the moisture reflectivity of the sky? Just a guess. I did notice the Fujinon did a better job at penetrating fog and haze during land comparisons. Maybe this moisture penetration has a difference on night sky observing? I do not really know. I am only guessing about the difference. Perhaps the optical engineers will come into this thread and venture an explanation.
Just like the Greek warrior Achilles, the mighty Fujinon musters up to capture the prize of this morning's beautiful autumn sky. Let us all shout for the Fujinon, who fails to lie down when faced with new competition.
--------------------
Bob
38°N
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