Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Porro vs. Roof.

  • Please log in to reply
35 replies to this topic

#1 paulsky

paulsky

    Apollo

  • -----
  • topic starter
  • Posts: 1131
  • Joined: 17 Feb 2004

Posted 20 March 2019 - 09:55 AM

Hello,

 The fact is that I came up with this question on the thread of another that is open, really a good binocular Porro can get to surpass in the aspect of image quality (I do not know if in mechanics) a good Roof binocular?
I know that the Birder community prefers the Roof to the Porro especially in its aspect of manageability and weight .. but in the astronomical theme ???
Has anyone been lucky enough to compare these two types of binoculars?
Best regards
Paul



#2 asphericalaberration

asphericalaberration

    Sputnik

  • -----
  • Posts: 35
  • Joined: 30 Jan 2019

Posted 20 March 2019 - 10:28 AM

Oh boy. This might be a controversial topic. My take: historically, porros had intrinsic optical advantages because porro prisms attain total internal reflection on all surfaces that function as mirrors. Historically, roofs were burdened by a phase-shift issue on one surface and a lack of internal reflection on another, requiring a silver or aluminum mirror coating on that surface. Roofs were dimmer. Good quality modern roofs fix both problems by using a special phase coating to eliminate the phase-shift and a dielectric coating for the applied mirror. The best modern roofs IMHO are about as good optically as best current porros. Technology fixed their intrinsic problems. Roofs remain more expensive, because they require special coatings and higher precision in manufacturing.

 

Roofs can be smaller, lighter, more robust, easier to waterproof, and less likely to become dirty internally (the external focusing in many porros doesn't seal them). Porros can be simpler, cheaper at the same level of quality, and provide a more three-dimensional image. Porros are popular in the astro community because their increased fragility and decreased sealing don't matter as much there as they do in the hunting and birding communities. Astro "likes" porros because because roofs of equal quality are much more expensive.

 

For various reasons, there are now very few top-quality porros in the new market. People lament that because a $400 porro might easily kick the snot out of a $400 roof optically (especially twenty years ago). When Nikon recently released its no-holds-barred astro bin, it was a roof design, however. It'd be nice to see more effort in the high-end porro market (if only an update of an old-school 7x35 11* with ED glass, full multi-coatings, and an aspherical element or two). That's not the buttered side of the retail bread, though.

 

Someone had to kick the bee-hive. Might as well be me.


Edited by asphericalaberration, 20 March 2019 - 11:07 AM.

  • Jeff Bennett, SandyHouTex, deepwoods1 and 8 others like this

#3 Binojunky

Binojunky

    Fly Me to the Moon

  • *****
  • Posts: 5423
  • Joined: 25 Dec 2010

Posted 20 March 2019 - 12:03 PM

A good porro beats a poor roof and vise versa,I have found that price makes a big difference no matter what style you buy,D.


  • dries1 likes this

#4 ihf

ihf

    Explorer 1

  • -----
  • Posts: 68
  • Joined: 14 Jan 2019
  • Loc: California, USA

Posted 20 March 2019 - 12:20 PM

As the Nikon WX was mentioned, shouldn't one distinguish between Schmidt-Pechan and Abbe-Koenig prisms when discussing "roofs"? Zeiss still offers them next to each other, so there must be different advantages.



#5 ngc7319_20

ngc7319_20

    Viking 1

  • *****
  • Posts: 719
  • Joined: 25 Oct 2015
  • Loc: MD

Posted 20 March 2019 - 01:03 PM

I've got about a dozen porros that I use for astronomy - Nikon, Fujinon, Swift, Pentax, Minolta, Bausch and Lomb... A year ago I tried an Oberwerk Sport 8x42 ED (roof prism) at the NEAF convention, bought the demo model on the spot, and now seldom use anything else.  The advantages of the small size / weight can't be overstated -- much easier to hold, can hold longer, less shake.  And I don't see that any image quality has been given up.  I'd always heard that porros were superior, but I think things have changed now.  Perhaps better manufacturing, coatings, aspherics, etc.


  • Paul Morow likes this

#6 gwlee

gwlee

    Surveyor 1

  • *****
  • Posts: 1588
  • Joined: 06 Sep 2015
  • Loc: 38N 120W

Posted 20 March 2019 - 02:08 PM

I have both and find there’s no PRACTICAL difference between the highest quality roofs and the highest quality porros for astronomy, except for cost, which is substantial. I prefer using my roof for travel because it’s more compact, and it has central focus, which makes it suitable for many other uses besides astronomy.

 

If I was starting over and wasn’t too concerned about cost, I would probably just by a high quality 10x50 roof and use it for everything that I do with a binocular, but buying an astronomy porro and a slightly smaller roof for critters would be a more versatile combination and cost about the same if both are of the highest quality. 


  • Paul Morow likes this

#7 MartinPond

MartinPond

    Aurora

  • *****
  • Posts: 4749
  • Joined: 16 Sep 2014

Posted 21 March 2019 - 12:06 AM

At the lower price end, the Porro can deliver more for the money.

Around $150 or more, the roof can match it pretty well.

One thing about roof binoculars in the middle shelf:

   they are produced in great quantities for hunting and birding,

   so their quality is amortized over many copies.

   The Nikon ProStaff  line is everywhere hunters load up, and

     it's amazing for the price. 

 

There are still classic Porros that are super though, like the Fujinons

   and Nikon Action Extremes.  

 

One thing about larger roofs......the weight isn't much less.

The prism complex gets massive.


Edited by MartinPond, 21 March 2019 - 12:07 AM.

  • Binojunky, ngc7319_20 and Simon B like this

#8 asphericalaberration

asphericalaberration

    Sputnik

  • -----
  • Posts: 35
  • Joined: 30 Jan 2019

Posted 21 March 2019 - 10:56 AM

Another facet of this topic is that roofs dominate the handheld market but porros dominate the "giant bin" market. Big, tripod-mounted astro/observation bins (e.g., 12x60, 15x70, 20x80, 25x100) are almost always porros. Are there any truly big roofs? Do roofs fail to scale well above handheld sizes for technical reasons, or is their absence above ~9x56 just a matter of cost, market size, and the general popularity of porros for dedicated astro use?



#9 Rich V.

Rich V.

    Fly Me to the Moon

  • *****
  • Posts: 6340
  • Joined: 02 Jan 2005
  • Loc: Lake Tahoe area, Nevada

Posted 21 March 2019 - 11:11 AM

Another facet of this topic is that roofs dominate the handheld market but porros dominate the "giant bin" market. Big, tripod-mounted astro/observation bins (e.g., 12x60, 15x70, 20x80, 25x100) are almost always porros. Are there any truly big roofs? Do roofs fail to scale well above handheld sizes for technical reasons, or is their absence above ~9x56 just a matter of cost, market size, and the general popularity of porros for dedicated astro use?

It's all about IPDs.  In the larger sizes, Porros create the offset of the optical axes that's necessary to provide a usable IPD range for most users.  The in-line optical paths of roof prisms generally get tricky with objective diameters over 60mm so that's their usual limit. 

 

Roofs are commonly used on larger binocular telescopes but they must incorporate swinging prism turrets that offset the optical paths back together to match the user's IPD.

 

Rich


  • Jon Isaacs, Carlos Flores, alpha_centauri and 1 other like this

#10 SandyHouTex

SandyHouTex

    Soyuz

  • *****
  • Posts: 3876
  • Joined: 02 Jun 2009
  • Loc: Houston, Texas, USA

Posted 21 March 2019 - 02:21 PM

It's all about IPDs.  In the larger sizes, Porros create the offset of the optical axes that's necessary to provide a usable IPD range for most users.  The in-line optical paths of roof prisms generally get tricky with objective diameters over 60mm so that's their usual limit. 

 

Roofs are commonly used on larger binocular telescopes but they must incorporate swinging prism turrets that offset the optical paths back together to match the user's IPD.

 

Rich

I never realized that, but I did wonder about it.  Great explanation.



#11 ngc7319_20

ngc7319_20

    Viking 1

  • *****
  • Posts: 719
  • Joined: 25 Oct 2015
  • Loc: MD

Posted 21 March 2019 - 02:30 PM

 

One thing about roof binoculars in the middle shelf:

   they are produced in great quantities for hunting and birding,

   so their quality is amortized over many copies.

   The Nikon ProStaff  line is everywhere hunters load up, and

     it's amazing for the price. 

 

This is a great point. The hunting / birding / boating market is probably many times larger than the astronomy market alone.  The quality per $$ is likely to be better than a binocular made custom for the astronomy market.



#12 follownoone

follownoone

    Lift Off

  • -----
  • Posts: 5
  • Joined: 13 May 2012

Posted 21 March 2019 - 04:21 PM

I use my bins for astronomy and bird watching. More use for many reasons bird watching. So for me Porro bins have a hard to describe 3-D affect and more depth of focus. Therefore I prefer them over roofs. I have all 3 of the SE series and Vixen 7x50. I doubt those advantages would be of much difference for astronomy and I would have to try a good roof someday to see if the advantages others have noted would be useful.



#13 dries1

dries1

    Mariner 2

  • -----
  • Posts: 220
  • Joined: 26 Oct 2017
  • Loc: Northwest Delaware

Posted 21 March 2019 - 06:15 PM

Some good explanations regarding the limitations regarding roof prism design. Yes the Nikon SEs are still great today for their uses.

I see now some very nice bino scopes with large magnification and aperture and this seems to becoming popular, not just for the night sky but for other applications.

 

But for less than 15X, the roofs seem to be the more popular choice. Anything bigger and one has to go the porro route as was previously stated. Perhaps some high end Nikon porros 10X56 or 12X60 or even a nice 15X60 will be made with center focus like the SE, but likely doubtful, a pity yes, but then again I am lucky to have the SE models.

 

Regarding the higher mag glass 10X-15X, IMO I have noticed that with respect to Roofs, the premium glass is much better than glass mid priced and below. The lower mag 7-8 X seem more competitive, since perhaps there are many more to choose from.  

 

I still use my EII 8X30 often, the last economically priced porro made by Nikon with very nice optics, and the 10X35, under a dark night sky.

 

Andy W.


  • Erik Bakker likes this

#14 Lt 26

Lt 26

    Vanguard

  • *****
  • Posts: 2331
  • Joined: 19 Feb 2009
  • Loc: Northwest Illinois

Posted 21 March 2019 - 06:57 PM

My favorite binocular is my 8x32se. If I were to purchase a binocular anytime soon it would be the E2. I own several roofs but prefer porros.

I also have two monoculars one roof and one porro. I use the roof a lot more.

Dereck

#15 gwlee

gwlee

    Surveyor 1

  • *****
  • Posts: 1588
  • Joined: 06 Sep 2015
  • Loc: 38N 120W

Posted 21 March 2019 - 07:01 PM

This is a great point. The hunting / birding / boating market is probably many times larger than the astronomy market alone.  The quality per $$ is likely to be better than a binocular made custom for the astronomy market.

The marine market is probably also much larger than astronomy market. 7x50 porros dominate the marine market and are also very suitable for astronomy although somewhat out of fashion for astronomy these days. 



#16 MartinPond

MartinPond

    Aurora

  • *****
  • Posts: 4749
  • Joined: 16 Sep 2014

Posted 21 March 2019 - 11:57 PM

I have too many great restored Porros,

 but if I tried roof, it might be 8x42, to take full advantage of the size.

 

I am settled on a 10x50 lightweight chassis I made into 

8.5 x 50  independent focus using Stellar EPs .... it's magic at night.

 

Looking at hundreds of shake/power posts,

I can see it'a always quite personal, between eye sharpness and 

shake, whether 7x or 8x or 10x or even 12x is best for you.

You gotta go try some.  



#17 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 76630
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 22 March 2019 - 02:42 AM

This is a great point. The hunting / birding / boating market is probably many times larger than the astronomy market alone.  The quality per $$ is likely to be better than a binocular made custom for the astronomy market.

 

I think one can assume that handheld binoculars are all made for the general market, none are Astro specific.

 

Jon



#18 ngc7319_20

ngc7319_20

    Viking 1

  • *****
  • Posts: 719
  • Joined: 25 Oct 2015
  • Loc: MD

Posted 22 March 2019 - 03:53 AM

I think one can assume that handheld binoculars are all made for the general market, none are Astro specific.

 

Jon

I'm thinking of the Nikon WX 10x50 at $6400, WX 7x50 at $6000, Astroluxe 18x70 at $1800, ProStar 7x50 at $1200, Tak 22x60 at $2000.  The advertising seems to target astronomy, though certainly you could use them for hunting or boating.  Stuff like "lens system allows you to take in a wide-sweeping view of star clusters or galaxies, while individual stars can be clearly seen as sharp points."  High $$$.

 

https://www.nikonspo...x-10x50-if.html

https://www.nikonspo...wx-7x50-if.html

https://www.nikonspo...luxe-18x70.html

https://www.nikonspo...ostar-7x50.html

 

I'm not sure where Fujinon fits in this scheme.  Literature for 7x50, 10x50, 10x70 mentions astronomy.  On the other hand I recall Fujinon 16x70 ads making a big deal about the fact that they float with the neck strap attached. Targeting boaters as well.  Not $6000 for that matter.


Edited by ngc7319_20, 22 March 2019 - 04:19 AM.


#19 sg6

sg6

    Fly Me to the Moon

  • *****
  • Posts: 5100
  • Joined: 14 Feb 2010
  • Loc: Norfolk, UK.

Posted 22 March 2019 - 04:28 AM

Have about 3 pairs of Porro's and 2 pairs of Roof's, my preference is the Roof's.

The Porro prism is one item and as it relies on total internal reflection they are "simpler" and should come out better. What I find is that the assembly that holds the prism is generally basic and the I get the idea that being easy to adjust the accuracy of accembly can be questioned. Sort of the user can adjust to suit.

 

Never been 100% convinced of the finish I have seen the Porro prisms either. Some are ground and that seems wrong for TIR.

 

The adjustment also tends to be a screw pressing on the glass, not a great idea to my thinking. The good ones are I suspect better. Well I hope so.

 

Yes roof's are sort of dominent in the birding world but it cannot all be size and weight, weight is so variable that it is not just the internal prisms. Also birder's will spend several hundred on binoculars and they want good optical binoculars, 50-100 grams difference will not apply. Accepting the lesser optics in favor of a slight weight difference is not a real excuse for Porro/Roof designs in birding, it is however in astronomy observing.

 

I half suspect that as Roofs cannot be adjusted that they are installed better, no adjustment would seem to mean they have to be.

 

So I will stick to Roof prisms. Been more then happy with them for the last 12 years.



#20 NDfarmer

NDfarmer

    Messenger

  • -----
  • Posts: 401
  • Joined: 02 Apr 2009

Posted 23 March 2019 - 06:20 PM

As the Nikon WX was mentioned, shouldn't one distinguish between Schmidt-Pechan and Abbe-Koenig prisms when discussing "roofs"? Zeiss still offers them next to each other, so there must be different advantages.

As far as the advantage of the AK prism vs. the SP.  The AK prism design is larger and requires a bigger housing, and for the

main binocular market, size is important, so the slimmer SP design is most popular in the 42mm and smaller models.

 

Zeiss just dropped the 42mm Victory HT AK models, and decided to stay with the superior Victory SF.

 

AK prism designs may be able to offer better transmission, and that is why you see them offered in the larger Zeiss 54 and

Swarovski 56mm models.



#21 NDfarmer

NDfarmer

    Messenger

  • -----
  • Posts: 401
  • Joined: 02 Apr 2009

Posted 23 March 2019 - 06:26 PM

At the lower price end, the Porro can deliver more for the money.

Around $150 or more, the roof can match it pretty well.

One thing about roof binoculars in the middle shelf:

   they are produced in great quantities for hunting and birding,

   so their quality is amortized over many copies.

   The Nikon ProStaff  line is everywhere hunters load up, and

     it's amazing for the price. 

 

There are still classic Porros that are super though, like the Fujinons

   and Nikon Action Extremes.  

 

One thing about larger roofs......the weight isn't much less.

The prism complex gets massive.

 

I think we should make sure we include the Swarovski Habicht porro models.  They are in current production and are

available in 8x30, 7x42 and 10x40.  They are available in both armored and regular construction, and with the top line

Swarovski lens coatings, they offer some of the highest optics available today.

 

I like binoculars, and have had all of the Nikon SE's, and also currently have all of the Swarovski porros.  These all perform

at a high level.

 

I don't want to post like a bragger, but just pointing out what is available.  cool.gif  


  • Erik Bakker likes this

#22 Erik Bakker

Erik Bakker

    Cosmos

  • *****
  • Moderators
  • Posts: 7778
  • Joined: 10 Aug 2006
  • Loc: Netherlands, Europe

Posted 24 March 2019 - 06:34 AM

Nowadays, the few porro's still in production with a high quality product in mind are the lowest priced entrance tickets to very high quality instruments and offer a wonderful viewing experience, especially so if you don't have to wear glasses. For the money payed, you get the best optical performance om axis. But for the aperture, they tend to be (much) more clumsy than their roof counterparts.

 

The views in the best of both designs are wonderful, yet significantly different due to the differences in characteristics of their prism designs and optical designs dated from very different timeframes often decades apart.

 

For sharp to the edge wide fields and best adjustability of eye guards, the best current generation roofs dominate the game.

For the best stereo impression at close-medium range, the porro's lead the field due to their inherent wider spaced objective lenses.

 

On axis contrast, light transmission and pinpointiness of stars are hard to beat in premium porro's. Only the very best roofs come close, but only at 2-3x the prices of the best porro's.

Swarovski is very open and realistic about this, having both types still in production. The startling clarity of their Habicht porro's is unmatched by even their EL or best SLC's. And it easily shows under the stars or at dusk/dawn observing nature.

 

We have to realize that the very small market remaining for quality porro's can have their extinction as a side effect. So if you like what these do best, get one new while you still can. Because some day, their availability new will have become a part of history. Perhaps sooner rather than later.

 

To a lesser extent, there is a roof prism design that I consider a threatened species: the Abbe König. With Zeiss now seizing production in there 42mm models, they only make the 54mm HT's with these prisms. And Swarovski only produce there 56 SLC's in this design.

 

There might come a day when binoculars with porro's and Abbe König prisms are no longer made new. Because the market put more emphasis on compact than light transmission or the highest contrast. Especially decades after use, because only porro and Abbe König prisms use total internal reflection and therefore don't need silvered optical surfaces to reflect light. And as we all know, even the best mirror coatings slowly degrade over time. 

 

Thankfully, we can all choose an instrument that suits our personal needs best. And there is more to binocular performance than the quality of their prisms alone.


  • John F, Grimnir and coz like this

#23 range88

range88

    Apollo

  • -----
  • Vendors
  • Posts: 1154
  • Joined: 26 Apr 2014
  • Loc: Shanghai

Posted 24 March 2019 - 06:57 AM

I like three dimentionality, so I like porro.
In this regard, some porros like mk43 still come top of the herd.
But I use roof more.

#24 FrankL

FrankL

    Viking 1

  • -----
  • Posts: 558
  • Joined: 30 Jul 2009
  • Loc: Winnipeg, Manitoba Canada

Posted 24 March 2019 - 01:52 PM

"And as we all know, even the best mirror coatings slowly degrade over time."

 

Well, yes, I've seen this with aluminum and silver coatings but not dielectric ones. If AR coatings don't degrade over time (other than through abuse) I don't see why dielectric ones would.


  • Jon Isaacs likes this

#25 asphericalaberration

asphericalaberration

    Sputnik

  • -----
  • Posts: 35
  • Joined: 30 Jan 2019

Posted 24 March 2019 - 05:05 PM

>AR coatings don't degrade over time

 

Dialectric coatings should last indefinitely, i.e., the life of the bin.




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics