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gweller
Saturday 12th April 2008, 11:40
Hi everyone

I've just got a pair of Nikon Monarch 8x36 as a backup to my main bins. They are quite nice apart from one thing which is driving me mad - the CA! Maybe it's just me, but I find CA to be most annoying.

Is this typical of roofs in this price range or are there some models better than others? I want to get a decent backup binocular without breaking the bank, but on the other hand I want something with a reasonable quality image otherwise I know I'm not going to use it.

Anyone got any ideas?

Cheers!
Gary

ThoLa
Saturday 12th April 2008, 13:04
Hi everyone

I've just got a pair of Nikon Monarch 8x36 as a backup to my main bins. They are quite nice apart from one thing which is driving me mad - the CA! Maybe it's just me, but I find CA to be most annoying.

Is this typical of roofs in this price range or are there some models better than others? I want to get a decent backup binocular without breaking the bank, but on the other hand I want something with a reasonable quality image otherwise I know I'm not going to use it.

Anyone got any ideas?

Cheers!
Gary

Mid-priced roof models are a mixed lot, to say the least.
There are good ones and really awful ones. Price is no indicator here!

If you can handle rudimentary German, I can send you a pdf with a comparitive test from 2006.

Cheers, Tom

gweller
Saturday 12th April 2008, 14:17
Mid-priced roof models are a mixed lot, to say the least.
There are good ones and really awful ones. Price is no indicator here!

If you can handle rudimentary German, I can send you a pdf with a comparitive test from 2006.

Cheers, Tom

Yes please Tom, much appreciated.

Cheers
Gary (mailto:gary.weller@gmail.com)

ThoLa
Saturday 12th April 2008, 14:55
Yes please Tom, much appreciated.

Cheers
Gary (mailto:gary.weller@gmail.com)


Okay, here they are.
If you have problems to download the pdfs, drop a line at
789-00(at)web.de
I'll zoom them out from there, if necessary.
Maybe there will be some useful information.

Best regards,
Thomas

MacGee
Saturday 12th April 2008, 20:30
Gary, all lower-priced roofs will show CA to a greater or lesser extent. Some lucky people aren't susceptible to it, but if, like me, you are susceptible, you can either train yourself to put up with it or get some porros.

Michael

ThoLa
Saturday 12th April 2008, 21:57
Gary, all lower-priced roofs will show CA to a greater or lesser extent.
Michael

Yes, and some very expensive ones have it, too.


you can either train yourself to put up with it or get some porros.
Michael

And many Porros have it, too.

with respect to CA the best mid-priced instruments I have seen are the Zeiss Conquests which have really very little (if these still fall into your mid-priced range ... which is not a well-defined category).

maybe there are others.

Tom

lucznik
Saturday 12th April 2008, 23:34
I have yet to see any binocular at any price that did not exhibit at least some CA. Of course, the most expensive binoculars almost always have much less but, it is still there.

MacGee
Sunday 13th April 2008, 01:23
And many Porros have it, too.You may be right, but though I have seen CA in Leica Ultravids and Nikon HG Ls, I have never seen it in any of the porros I've had. Of course I don't go looking for it, so maybe I only notice it when it reaches a certain level of grossness.

Michael

henry link
Sunday 13th April 2008, 01:45
I agree with Michael about this. Expensive "alpha" binoculars are some of the worst offenders when it comes lateral CA (which is the form of CA you see in binoculars). I haven't figured out why, but I think the complexity of the optics in these binoculars is probably at the root of the problem, particularly the widely spaced objective elements used for internal focus. I've tested a number of binoculars for this aberration recently. The best of the lot was my neighbor's cheap Bushnell 7x35 Porros from Walmart with BK7 prisms.

gweller
Sunday 13th April 2008, 11:01
I have a pair of Opticron 8x32 SR GA porros and these have virtually no discernible CA. In fact for the price they are very, very good pair of bins - it's a shame they are not more widely available as I'm sure they would be very popular with birders. Downside is, they are not waterproof, hence me looking around for a pair of low or mid priced roofs.

If I'm correct in thinking that porros suffer less than with CA than roofs, maybe I should look at getting a pair of waterproof porros? Although here the choice is rather limited I think

Cheers
Gary

ThoLa
Sunday 13th April 2008, 12:41
If I'm correct in thinking that porros suffer less than with CA than roofs, maybe I should look at getting a pair of waterproof porros?
Cheers
Gary

No. Chromatic abberation is a physical phenomenon that every single lens in the world shows.

The question is: how much effort does a manufacturer put into correcting it?
How will this affect other unavoidable lens abberations?

It is not possible to predict in advance how much CA or any other abberation a specific model will show.

Which other criteria are important to you?
Only CA?

Every instrument is a compromise. Only relative strenghts and weaknesses vary.
Different people have differing priorities.
Tom

MacGee
Sunday 13th April 2008, 17:26
I have a pair of Opticron 8x32 SR GA porros and these have virtually no discernible CA. In fact for the price they are very, very good pair of bins - it's a shame they are not more widely available as I'm sure they would be very popular with birders. Downside is, they are not waterproof, hence me looking around for a pair of low or mid priced roofs.

If I'm correct in thinking that porros suffer less than with CA than roofs, maybe I should look at getting a pair of waterproof porros? Although here the choice is rather limited I thinkI had the 8x32 SR GAs too, and generally liked them, but ended up replacing them with the waterproof Opticron 8x42 HR WP (http://www.gadget-bag.co.uk/product_details.php?id=2833)s. These are heavier and have a smaller FOV than the SR GAs, but the far superior view more than makes up for these deficiencies and I've never regretted changing. And I've never noticed any kind of colour fringing in them.

Michael

gweller
Monday 14th April 2008, 13:19
I had the 8x32 SR GAs too, and generally liked them, but ended up replacing them with the waterproof Opticron 8x42 HR WP (http://www.gadget-bag.co.uk/product_details.php?id=2833)s. These are heavier and have a smaller FOV than the SR GAs, but the far superior view more than makes up for these deficiencies and I've never regretted changing. And I've never noticed any kind of colour fringing in them.

Michael

Mmmmm... too heavy and too narrow a FOV for me. Seriously thinking about saving the pennies up and going for a Swarvorski Habicht 8x30. Decided I really like the porro format and this seems to one of the best.

Cheers
Gary

ThoLa
Monday 14th April 2008, 14:00
Mmmmm... too heavy and too narrow a FOV for me. Seriously thinking about saving the pennies up and going for a Swarvorski Habicht 8x30. Decided I really like the porro format and this seems to one of the best.

Cheers
Gary

there has recently been a discussion of these interesting models.
http://www.birdforum.net/showthread.php?t=102060

Tero
Wednesday 16th April 2008, 17:09
I never liked the 36mm Monarchs for some reason (if I make all these compromises, might as well go 32mm for compactness), but 42mm also have CA. Even my Zeiss 10x40 has it. ED glass bins for you? There are a few models, heavy.

MacGee
Thursday 17th April 2008, 14:47
Seriously thinking about saving the pennies up and going for a Swarvorski Habicht 8x30. Decided I really like the porro format and this seems to one of the best.According to the Kikkertspesialisten reviews the Habicht is almost identical to the SR GA in optical performance - the Habicht does score 10- for contrast as against the SR GA's 9+. And it does have better edge sharpness, build quality and glasses-friendliness. On the face of it that doesn't look like a vast improvement for quite a lot of money, but statistics can be deceptive. If you do get the Swarovski, I'd be very interested to hear how it works out in practice.

Michael

lucznik
Thursday 17th April 2008, 16:23
Wait. You're saying that they are "almost identical in optical performance" except that the Swarovski offers:

* better contrast
* better edge sharpness
* better build quality
* better eyeglass friendliness

That seems to me like quite a bit of difference. In what ways then are they "almost identical in optical performance?"

henry link
Thursday 17th April 2008, 17:37
I would not call the 8x30/10x40 Habichts "eyeglass friendly". Eye relief is 12mm and the eyecups on the leather versions are so stiff they sometimes explosively pop up from the rolled down position. I've owned many Swarovski Porros, both Habicht and SL. The only one I would recommend to birders is the 8x30W Habicht, preferably the rubber armored version and only a unit made in the last few years of production to avoid a very yellow color bias. But, IMO the 8x32 SE and even the 8x30 EII are optically better in nearly every way.

MacGee
Thursday 17th April 2008, 18:34
Wait. You're saying that they are "almost identical in optical performance" except that the Swarovski offers:

* better contrast
* better edge sharpness
* better build quality
* better eyeglass friendliness

That seems to me like quite a bit of difference. In what ways then are they "almost identical in optical performance?"The three main measures of optical quality used by Kikkertspesialisten are resolution, brightness and contrast. Resolution and brightness are the same, contrast in the Habicht only marginally better. Build quality and eyeglass friendliness I don't consider optical qualities. Which leaves edge sharpness. I disregarded that because it's not a priority for me, though I should have remembered that others see it as a sine qua non.

I just didn't think this added up to a difference worth saving up for. I think Gary would be better following Henry's advice and getting one of the Nikons, if he can find one.

Michael

gweller
Friday 18th April 2008, 10:43
.... I think Gary would be better following Henry's advice and getting one of the Nikons, if he can find one.
Michael

Problem is, the Nikons are not waterproof are they? Although the SE is water-resistant I think.

Cheers!
Gary

ThoLa
Friday 18th April 2008, 12:13
Problem is, the Nikons are not waterproof are they? Although the SE is water-resistant I think.

Cheers!
Gary

Hello!
Just had a chance to test a Swarovski Habicht 10x40 yesterday.
Can't think of any reason why they are so hard to find.
Excellent. Exquisite. Wonderful.
No more CA in it than in the 8x32 Ultravid HD (tested 2 minutes later).
The Habicht is better (!) in terms of distorsion.
These underrated instruments must reign in the realm of best value for money.

Very personally opinioned,
Tom