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05-11-2010, 01:38 AM   #121
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QuoteOriginally posted by Derridale Quote
Just two examples taken with the 180 from quite a distance......
Impressive shots!
QuoteOriginally posted by Derridale Quote
Anyway - back to the original topic - I have the 8-16mm on pre-order with Adorama,
Awesome. Can't wait to read about your first impressions.

QuoteOriginally posted by Derridale Quote
...given that I already have a Pentax 77mm LTD, I'm wondering if there is anything to be gained by trying the Sigma 85/1.4?
Well, it is a different focal length. You get a different perspective for the same framing and for portraits this can result in a more flattering look. The greater focal length also helps with blurring the background. Finally, the Sigma is faster. However, it is impossible to say whether you'd be gaining anything without knowing the 85/1.4's performance. The FA 77 is a fantastic lens and it will be difficult to come close or even surpass it. On the other hand, if you asked someone if there is something to be gained by having a Pentax A* 85/1.4 in addition to an FA 77/1.8 I reckon most would answer "Yes".

QuoteOriginally posted by Digitalis Quote
Zeiss lenses are well known for doing it and they are supposedly designed to be relatively unscathed by such egregious lens design bloopers.
CA is not a design bloop. It is impossible to avoid. You can minimise it by using exotic and very expensive glass but I reckon at the expense of other qualities (in addition to affordability).

QuoteOriginally posted by Digitalis Quote
I don't like it when a company labels a lens APO when it really isn't.
Fair point. The same can be said about the "Macro" designation which is also often used in a liberal manner. However, Sigma is not know to have inflated prices, using false pretences.

QuoteOriginally posted by Digitalis Quote
But the aberrations are still there - you can correct and image till the cows come home but it isn't going to look as good as an image taken with a lens that didn't have the same flaws.
I think you are throwing CA and spherical aberrations and other imperfections all into the same pot. To the best of my knowledge CA can be very well corrected, often by very simple means (just scaling a colour channel, i.e., reversing what the lens did in the first place). If the lens has more complex behaviour, then there is software like DxOMark which applies a much more complex correction (where the local correction depends on the position in the image).

QuoteOriginally posted by Digitalis Quote
...focused at infinity
How did you focus at infinity?
I'm sure you are aware of the fact that you cannot use the infinity marker on the lens, let alone the end position of the focus ring. Perhaps your lens needs AF adjustment near the infinity region? BTW, the fact that is optically fine at near distances does not rule out a potential problem near infinity. It could still need an alignment of some sort.

05-11-2010, 06:05 PM   #122
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8-16 has arrived in stock.

.

Sigma 8-16 is in stock now at Adorama and B&H, shipping, and several Nikonians have actually picked one up yesterday and today at the stores in NYC.

As far as I can see, only the Nikon + Canon mounts have appeared as of today.

Exciting, especially in light of Photozone's review....


.
05-11-2010, 06:49 PM   #123
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QuoteOriginally posted by jsherman999 Quote
.

Sigma 8-16 is in stock now at Adorama and B&H, shipping, and several Nikonians have actually picked one up yesterday and today at the stores in NYC.

As far as I can see, only the Nikon + Canon mounts have appeared as of today.

Exciting, especially in light of Photozone's review....


.
I have an 8mm f4 showing up from Ador tomorrow so I'm out for now.
05-11-2010, 07:15 PM   #124
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QuoteOriginally posted by jsherman999 Quote
.
Exciting, especially in light of Photozone's review....
To save Google a number of searches, here's the link to the Sigma AF 8-16mm f/4.5-5.6 DC HSM - Lab Test / Review by Photozone (again, the original one is a number of pages from here).

05-11-2010, 07:21 PM   #125
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QuoteOriginally posted by Blue Quote
I have an 8mm f4 showing up from Ador tomorrow so I'm out for now.
what lens is this?
05-11-2010, 07:28 PM   #126
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QuoteOriginally posted by jezza323 Quote
what lens is this?
It is the Sigma 8mm f4 AF fisheye that was replaced by the 8mm f3.5 version. i was poking around Ador and they had this one in their used section. It popped up on a Sigma 8mm search. Hopefully, I'll be able to post in the FE Fever club thread.

Last edited by Blue; 05-11-2010 at 07:33 PM.
05-12-2010, 07:20 AM   #127
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Those damn Canikon types - they always get the first fun!

I've hade my Siggie 8-16 on order from Adorama for some time now, but obviously will still have to wait for the Pentax fitting.... bummer!

Meanwhile, I just picked up a Sigma 50mm f/1.4 yesterday (I'm visiting London, and picked one up tax free) and so far it seems to be tack sharp and looks VERY impressive. I went into another store with the K20D hanging around my neck and the new Siggie 50mm f/1.4 on it, and two of the store guys came straight over and said "Wow - is that the Sigma 50/1.4??? Great lens".

Damn this LBA...!

Or, on the other hand - I LOVE this LBA...!
05-12-2010, 07:56 AM   #128
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"How did you focus at infinity?"

Don't play semantic games, it really ticks me off when people do that. I manually focused at an approximate distance of 150m and at f/5.6 the DOF should extend far enough to reduce user error. And still, my Sigma 100-300 f/4 zoom was consistently sharper...even my Tamron M42 200mm f/3.5* was sharper than the Sigma 180mm f/3.5 macro at that distance. I don't think there is anything wrong with my lens, I did a quick check for any alignment errors and everything seems to be in order. The probability of something being wrong with the optical assembly seems a bit far fetched, because the closer you focus a lens the more strain on any optical errors will be and the sigma 180 is extremely good at macro distances.



see what I mean?, the subject is crisply rendered, no signs of any deficiencies in image quality whatsoever.

The sigma 180mm f/3.5 EX DG just gets softer and softer at longer distances over 8~15 feet and beyond to the point where even a zoom provides clearly superior contrast & resolution, even at f/11.

Macro lenses are typically** not very good at long distance work. It seems like that rule of the thumb still remains standing in the digital age.

And as for DxO...I would rather be out taking photos with lenses that don't have any show stopping performance issues, instead of sitting in front of my computer while it calculates the corrections for optically inferior lenses. I agree, CA isn't as much of a show stopper as it used to be, providing it is within certain limits. But PF still is ; And that is what I was referring to in regards to Zeiss lenses....but each to his own.

*I use this lens as a bookend, I don't have much use for it.
**there are several notable exceptions


Last edited by Digitalis; 05-12-2010 at 08:09 AM.
05-12-2010, 02:37 PM   #129
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QuoteOriginally posted by Digitalis Quote
Don't play semantic games,
That was not my intention. You wrote "focused at infinity" and that could mean a lot of things. I was just trying to find out whether there were was an explanation for your experience lurking somewhere.

QuoteOriginally posted by Digitalis Quote
The probability of something being wrong with the optical assembly seems a bit far fetched, because the closer you focus a lens the more strain on any optical errors will be and the sigma 180 is extremely good at macro distances.
Yes, but this assumes that the lens doesn't have a defect. It probably doesn't but if it had a floating element group that didn't move properly than its positioning could be fine for small distances but inappropriate for longer distances. I'm not claiming to know enough about lenses to be sure that near distance performance always implies something about far distance performance.

QuoteOriginally posted by Digitalis Quote
Macro lenses are typically** not very good at long distance work.
It is true that they are optimised for short distances. Whether that explains the far distance performance of your copy, I don't know. It may very well do so.

I sense an irritated tone in your post. I didn't mean to irritate you, I was just trying to explore whether the source of the problems you experienced really is the lens model or something else.
05-12-2010, 03:26 PM   #130
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QuoteOriginally posted by Digitalis Quote
the sigma 180mm f/3.5 APO EX DG isn't bad either, just don't try using to focus on something that is further than 8 feet away; the image quality degrades very sharply.

sigma 100-300 f/4 APO EX DG is a bit over rated I own one and to be honest, you have to stop the thing down to f/8~f11 (depending on focal length and how close your subject is) to get consistent image quality. apart form that it's not bad.

These two comments almost make me wonder (wild guess, maybe nothing to it) if your camera body may be focusing inconsistently. I haven't heard of any problems with the 180 macro at distance, and my 100-300 f4 is the model of consistency at f/4 and f5, so much so that I rarely shoot it at anything smaller than f/5 unless I need more DOF.



f/5, 300mm:






QuoteQuote:
70mm f/2.8 - I don't like short macro lenses, for starters they aren't Apochromatic. APO lenses below 100mm don't exist. I never have had a need/use for them. Though I appreciate how sharp it is.
I don't think I understand your comment about APO here - APO designs are not the only way to combat CA and spherical aberrations. I need to try to make my Sigma 70 show CA... It's pretty well controlled.

Photodo review of Sigma 70:

QuoteQuote:
Chromatic aberrations are so well controlled that similar, negligible readings were recorded throughout the aperture range and are as good at the edge as in the centre.
SLR gear review of Sigma 70:
QuoteQuote:
Chromatic aberration is well on the low side of average across the aperture range, increasing very slightly at f/22.
05-12-2010, 04:45 PM   #131
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I wasn't bashing the Sigma 70mm f/2.8 Macro, Sigma make quite a few good macro lenses it's hard to choose. Though I don't like the working distance of the shorter ones below 100mm, I deal with a lot of difficult subject matter with my macro work where having elbow room with my working distance is crucial. the Pentax AF160FC ring flash is a very useful accessory with this lens.It's actually quite powerful for a ringflash the canon ringflash has half the GN, at twice the cost.

"floating element group that didn't move properly than its positioning could be fine for small distances but inappropriate for longer distances"

-As far as I know the Sigma 180mm f/3.5 does use floating lens elements, and if the were placed in a less-than-optimum distance; The DOF (depth of focus) at the sensor plane would make such an error largely irrelevant(unless it was a huge error). Besides, when I bought it I checked the mechanical condition of my lens and it is superb. Additionally Depth of focus at the imaging plane gets smaller the closer you focus so if there was any error it would be blindingly obvious across the whole focal range of this lens due to the nature of floating element designs. As you can see with the image I posted above, this clearly isn't the case.


"your camera body may be focusing inconsistently"
- I was focusing manually on a subject 150m away at f/5.6 it would take a spectacular error on my part to misfocus that.

"I don't think I understand your comment about APO here - APO designs are not the only way to combat CA and spherical aberrations. I need to try to make my Sigma 70 show CA... It's pretty well controlled."

- Apochromatic doublets are still the best way to combat it. In regards to your comments on image quality about the Sigma 100-300mm f/4 APO Ex DG, I was pointing out that the image quality isn't very good approaching minimum focusing limit,especially at 300mm. So stopping it down to f/8~f/11 helps a lot with that. Besides producing good bokeh becomes more problematic the closer they are focus using wide apertures.

Last edited by Digitalis; 05-12-2010 at 05:00 PM.
05-12-2010, 05:01 PM   #132
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QuoteOriginally posted by Digitalis Quote
...In regards to your comments on image quality about the Sigma 100-300mm f/4 APO Ex DG, I was pointing out that the image quality isn't very good approaching minimum focusing limit,especially at 300mm. So stopping it down to f/8~f/11 helps a lot with that. Besides producing good bokeh becomes more problematic the closer they are focus using wide apertures.
.

I might agree there, in fact both the 100-300 f4 and 50-150 2.8 have problems wide-open at or near MFD, and I've heard the 70-200 2.8 does also. I think Sigma tried too hard for an impressive MFD, and couldn't deliver. For ever other distance besides 'near-mfd', though, my 100-300 and 50-150 are pretty fantastic.
05-12-2010, 10:15 PM   #133
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I believe it wouldn't make sense building an APO lenses in the lower 100mm especially if the LD elements are more than capable of combating CA and SA and the difference between the LD and APO lenses are indistinguishable. I dont think people would pay the additional premium just for having an APO lens. practicality would essentially win over bragging rights.

"guy 1: hey, I got an APO lens !

guy 2: so what, my lens is as good as your APO lens, at a cheaper cost. "
05-13-2010, 04:17 AM   #134
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The Sigma 85/1.4 has a recommended retail price in Europe now: 1099 Euro.
This can be converted into a street price of about 850 Euro.
05-13-2010, 04:38 AM   #135
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i think it's too much for the 85, with little effort you could pick the FA 85 or at the same price the FA77...i'm disappointed as i was really hoping to see it in the 500 range.
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