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Forum: Digital Processing, Software, and Printing 06-27-2009, 05:11 PM  
Poll: Operating System and Image Software
Posted By zaurus
Replies: 71
Views: 12,520
Forum: Pentax SLR Lens Discussion 06-22-2009, 04:39 PM  
Thoughts on 77mm limited and 55mm SDM
Posted By zaurus
Replies: 29
Views: 5,912
I see the "old skool" vultures have jumped on Mr. The Guy for him pointing out the truth about the FA 77.
Let me quickly and easily dispose just of the latest more obnoxious one.

The DA 70 has a fov of 105mm equivalent.
The DA* 55 has a fov of 83mm (close enough to 85) equivalent.
Both classic, established portrait lengths.
Where does the 120mm equivalent of the FA 77 stand?
Nowhere.

OK, 77mm had a weird fov on film, and even weirder fov on digital crop.
Your point being...?

Aaaaah, I see.
Have you ever crossed your mind that you are changing the perspective -- critical for portraits?
Probably not.
So that you know -- there are this and other good reasons for choosing particular focal lengths over others.

I guess, yes, he talks about that, including lateral CA.

They might be small (ANY lens has some) for this particular FA lens, but CAs are a problem for instance on the FA 43.
So:
His point stands -- these corrections are possible only on D(F)A lenses, hence this is one more reason to choose modern lenses
instead of old film ones.


Actually you go back to your pre-digital existence ("cave").
First learn there how to behave in a civilized manner on a public, digital, Internet forum -- and then come back here.

Or, don't come back, never buy modern cameras and lenses, never use email and Internet.

You will not be missed.
Forum: Pentax SLR Lens Discussion 06-17-2009, 03:00 PM  
Canon equivalents
Posted By zaurus
Replies: 28
Views: 4,158
I am in a very similar situation, however, I maintain currently both a Pentax and a Canon system.
This is becoming rather cumbersome and I have to make my mind one way or the other soon.
I have experience with the 40/2.8, 16-45/4 and 50-200/4-5.6 for Pentax (K100D).
I have experience with the 28/1.8, 50/1.4, 100/2, 17-55/2.8, Tokina 11-16/2.8 -- all for Canon (XSi/450D).

These are my observations, in no particular order as anybody's priorities are different.
  • Speed
    The Limiteds are no low-light lenses and for me this is a bigger deal than I initially thought. If I have to use a flash, then I'd rather use any of the excellent Pentax f/4 zooms as they are quite compact, and the bulk comes from the flash(es).
    Falling back to FA* Limiteds is not feasible for me for a number of reasons (the 31/1.8 is expensive, all other have "weird" focal lengths in crop terms, there is no wide angle one, etc.).
    Handling of the DA 40 is indeed a bit awkward as it is very small, and it is a bit too long for use indoors.
    I really wish they made a DA 35/1.8 Limited (not Macro) instead of both the 40 and the 35 Limiteds.
    As many others, I was also looking forward to the 30/1.x, but that disappeared from the roadmap.

  • Autofocus
    Limiteds are screw-drive only, and focus more slowly and less precisely than the Canon USM primes.
    The newer Rebel bodies have also a center AF censor which is additionally sensitive and even more precise with lenses 2.8 and faster -- this made difference for me when shooting low light concerts and other performing arts.

  • Noise
    Screw-drive noise might become bothersome sometimes, mostly on the zooms, it was no problem with the DA 40.
    Canon USMs, as you know, are very quiet.

  • Optical quality
    The single best feature of the DA Limiteds is that they are equally good at all aperture settings and one does not need to "mentally adjust" to achieve optimal results.
    In contrast, the Canon 28/1.8 and to some extent the 50/14 are a mixed bag.

  • Stabilization
    In-body Pentax SR helps, but can't compensate for DA Limited's low speed for my type of shooting.
    If one shoots anything over 135mm (200mm equiv) then the Pentax viewfinder becomes very "jittery" unlike Canon's IS which stabilizes the viewfinder -- a must for sports and wildlife.
    Hence, I sure wish Pentax would stop introducing overlapping longer telephotos as the market for those is very small.
    And instead make a fast normal and/or wide prime (Limited) and a 2.8 ultra-wide DA* zoom (cf. Tokina 11-16mm).

  • Price
    I think both systems are fairly priced.

  • Misc
    Canon does not have any EF-S primes ATM besides the 60/2.8 Macro.
    The build of the DA limiteds is exceptional, the Canon one is "merely" very good and this is reflected in the respective prices.
    The new DA* 55/1.4 might be mandatory for both portraits and low-light short tele.


After all this, if you still insist on switching to a Pentax Limiteds-only line-up, I would advise you to definitely get the 21/3.2 and the 70/2.4, and/or optionally the 55/1.4.
Get one or more AF360-FGZ flashes (which serve both as master and slave) and use them in P-TTL or manually on or off the body utilizing the built-in wireless (IR) master mode of the K-7 pop-up flash.
Forum: Pentax SLR Lens Discussion 01-15-2009, 07:04 PM  
Which Pentax-branded lenses are based on third-party (optical) design?
Posted By zaurus
Replies: 29
Views: 5,478
The official 50-135mm f/2.8 press release of the US distributor of Tokina is dated September 1st, 2006 containing full specs and quoting availability date November 2006:
THK Photo Products, Inc. Announcement of Tokina 50-135mm

An extensive hands-on review of a production Tokina 50-135mm is dated December 15th, 2006:
Tokina AT-X 535 PRO DX 50-135mm F2.8

Both is way ahead of the Pentax announcement.

Also, keep in mind the Nikon version is using a screw drive, whereas the Canon version a micro-motor, so Tokina would have needed more time than Pentax to put into production the lens in both mounts once the optical design has been set -- but in fact Tokina delivered the lens before Pentax.

All this clearly shows Tokina was the (primary) designer the lens.
Forum: Pentax SLR Lens Discussion 01-14-2009, 02:07 AM  
Which Pentax-branded lenses are based on third-party (optical) design?
Posted By zaurus
Replies: 29
Views: 5,478
Not only you both contradict each other, but again neither has any shred of evidence.
OK, I'll try once more again to make it as explicit as I can.
1. The only lens Pentax has claimed "co-design" with Tokina is the 10-17mm fish-eye. This is the only lens Pentax has announced and delivered (seven (7) months) before Tokina.
2. Pentax did NOT claim "co-design" with Tokina of any other lens after that. Since then ALL lenses with common optical design have been announced and delivered by Tokina way ahead of Pentax.
3. Tokina has delivered the 11-16mm f/2.8 which is an integral part of their pro line-up (11-16mm, 16-50mm, 50-135mm) -- which is not even on the Pentax roadmap.

True, all of this is not direct evidence, but I doubt it will ever get more clear than this.
The only possible conclusion is:
Tokina has designed all lenses which have a common optical design with the Pentax counterparts (with the exception of the fish-eye).
If you have credible evidence for the opposite, please share.
Repeat: evidence, not wishful thinking, or fanboyism.


You indeed successfully managed to say nothing with this vague statement, congratulations.
However, if you meant to say "the Pentax version is better" -- you are wrong, again.
Photozone rates both the Canon and Nikon version of the 50-135mm f/2.8 at least equal, and even better than the Pentax one:
tokina-af-50-135mm-nikon
canon-eos-tokina-af-50-135mm
pentax-smc-da-50-135mm
Forum: Photographic Technique 01-13-2009, 12:56 AM  
The almost full frame Pentax?
Posted By zaurus
Replies: 44
Views: 9,927
OK, what is a "standard" or "existing" media?
Are we talking here "common use" or "for exhibition/clients"?

I have three digital displays with ratios 4x3, 5x4 and 1920x1080 (pixels) and a notebook 1680x1050 (ratios 16x10 and 16x9 are common too).
I print 12"x10" and 14"x11", mainly (sometimes 19"x13").
People in Europe might print A3 and A2 etc.

Give me the maximum area, don't force me to awkwardly rotate the body, and I'll happily crop each time -- as required by the image (I am doing this anyway).
Forum: Pentax SLR Lens Discussion 01-13-2009, 12:27 AM  
Which FA and DA lens are shared with third party lens makers?
Posted By zaurus
Replies: 1
Views: 2,802
Forum: Digital Processing, Software, and Printing 12-25-2008, 11:18 PM  
Linux guru, DSLR n00b: how do I formulate a good workflow?
Posted By zaurus
Replies: 3
Views: 4,452
You being a Linux guru, you'll have no problems finding out the postings of a fellow Linuxer, producing a customized Linux distribution, namely mattdm.
Also, using basic search, you've found out the postings of a guy developing on Linux (me). completey address the questions you have raised.

Unfortunately, being a Linux guru nowadays is not offbeat, but more like a mainstream already.

Of course, there are still "Windoze" users around here, but we have to be patient with them, hoping they will eventually see the light, no matter how long it takes.
At that point, we have to be very patient, forgiving and understanding.
Nothing less would cut it -- they are very sensitive, and more like the "old school."
Forum: Digital Processing, Software, and Printing 12-25-2008, 11:00 PM  
Difference between monitor calibration devices?
Posted By zaurus
Replies: 16
Views: 5,220
ftpaddict, you sound totally confused.

Are you talking about the hardware -- Spyder2 vs. Spyder3?
Or, alternatively, are you talking about the software -- Express vs. Pro?
Or, you have no clue, and want to hear a diversified plethora of opinions?

Please do clarify if you want to hear a coherent maybe meaningfull reply.
Forum: Digital Processing, Software, and Printing 09-23-2008, 06:17 PM  
Linux color calibration dilemma - suggestions?
Posted By zaurus
Replies: 16
Views: 16,994
Possible, but not yet proved.


When switching to a color profile using:





Code:

@lex:~> dispwin .color/icc/eizo-685.icc



I also initially get surprised by an alleged light brownish/reddish cast, but this impression goes away in a couple of minutes and "measurements" prove the color fidelity is much better.



I have an Intel MacMini with a DVI output and my Eizo 685 has dual-DVI inputs, so I can compare calibration results by push a button "next to each other," so to speak.
To my eyes when inspecting them using e.g this standard LCD test the Linux one looked better.
However, it might be the difference between using integrated GMA950 on the MacMini vs. discrete Nvidia on openSUSE.


It might also be the quality of the driver for your graphics card -- as the "calibration process" actually changes its values (unless you have a professional hardware-calibrated monitor).
On openSUSE I am using a Nvidia FX-5700 with the Nvidia proprietary binary driver which is supposedly the same (or close) for any OS.



I assume you are using the process described here.
Are you sure you are using optimal settings?
How many patches did you use (default and 250 are way too little)?
I used 500 (if I remember correctly).
It took 28 minutes on my dual Opteron workstation.





Code:

@lex:~> ls -l eizo-685.*

-rw-r--r-- 1 x users 10266 2008-02-18 20:08 eizo-685.cal

-rw-r--r-- 1 x users 4016 2008-02-18 20:44 eizo-685.icc

-rw-r--r-- 1 x users 25390 2008-02-18 20:13 eizo-685.ti1

-rw-r--r-- 1 x users 32703 2008-02-18 20:41 eizo-685.ti3



Haven't checked with printed out charts.
Wish there was an easy standard automatic way to measure deviation, not to rely on subjective impression...
Forum: Digital Processing, Software, and Printing 09-14-2008, 05:19 PM  
Linux color calibration dilemma - suggestions?
Posted By zaurus
Replies: 16
Views: 16,994
OK, I'll give a last try and spell it out as clear as I can.

I have the Spyder2 calibration device.
Using it, I calibrated my two Eizo monitors (L887 and L685) under both openSUSE and Ubuntu Linux.

The result of the calibration under Linux is vastly superior to the one performed under MacOS 10.5 using the "Express" and "Pro" versions of the bundled Datacolor software (yes, I have a Mac, too).

So stop this insanity with creating profiles under "Windoze" and copying over, or, using a virtual machine etc.

Refer to my post above, go to the attached link in the knowledge base and follow the directions.
It is as simple as that.



cpopham, I've been participating in and moderating Internet forums since 1994 and your attempt to instruct me and redefine what netiquette is pathetic.
Either you participate constructively and on topic, or else shut up and go fill the gaping holes in your computer-related knowledge.
Start with the FAQ on how to participate in forums.
Forum: Digital Processing, Software, and Printing 08-30-2008, 08:28 PM  
Linux color calibration dilemma - suggestions?
Posted By zaurus
Replies: 16
Views: 16,994
Do you absolutely need any of the additional features of Spyder3? Probably not, as even Datacolor recognizes it and continues to sell Spyder2 Express.
Moreover, third-party software also does not support many of its features, for example Eizo's Color Navigator.

So yes, return it and buy cheaply a Spyder2 device, even second hand and without bundled software.
For how to use it effectively, refer to this entry in the Forum's Knowledge Base.


This is false.
Instead of spreading FUD please educate yourself by reviewing the Knowledge Base at the link posted above.


Another bad piece of advice.
Why should anybody (especially a Unix user) use a 9-years old 32-bit OS lacking vital features of a modern OS (e.g. package management)?
Just because MS cannot come with something better?

Linux is more than adequate for an (advanced) amateur.
For professionals there is another flavor of Unix available -- MacOS.


Another over-generalization, typical for a Windows user.
I know of professional photographers using Macbook Pros.
The Thinkpad W700 has been created specifically for photographers.
Forum: Pentax SLR Lens Discussion 05-02-2008, 01:45 AM  
Poll: Indoor fast prime
Posted By zaurus
Replies: 21
Views: 4,359
I stubbornly tried using it for months for this purpose but finally conceded defeat -- it simply does not work.
Too much of a compromise in every direction.
A bit too narrow, a bit too slow.

The Sigma 28mm f/1.8 which I also used to have is not a good choice either.
f/1.8 is unusable for groups due to extreme shallow DOF so you always end up at f/2 at least.
It is very bulky and wobbly as well.

Get the 35/2 on a budget or the 31 if money is not a problem.
Heck, for portraits go for the Sigma 30/1.4 (despite its corner softness).

Or, get a flash.
That's what I did.
Forum: Photography Articles 05-02-2008, 12:03 AM  
Complete color management and workflow under Linux -- from a Pentax user
Posted By zaurus
Replies: 14
Views: 16,809
Firstly, some printing shops, e.g. Costco have put online their printer profiles for download and use.
Secondly, some programs, Digikam and CinePaint among them, allow for the only meaningfull end-to-end color management (including camera color space, monitor profile and printer profile along with automatic conversion among them).

If you are happy with your workflow, this is fine.

In my personal opinion, complying to all of the above leads to consistent and improved results.
I am mainly following the excellent J. Cornuz write-ups cited above.
Forum: Digital Processing, Software, and Printing 05-01-2008, 11:47 PM  
LightZone Linux Version 3.5 Released!
Posted By zaurus
Replies: 4
Views: 2,742
Yes, I have been using their betas for quite some time.

Sure, I will be buying it, although I have and use everyday a full stack of open source tools.
But -- Linux + Java, what could be better?

Away, away, away from the slavery, dumbness and obsoleteness of "Windows!"
Forum: Sold Items 04-15-2008, 03:24 PM  
For Sale - Sold: FS: DA 40mm f/2.8 Limited; Hoya, Tiffen filters
Posted By zaurus
Replies: 4
Views: 2,904
Price of the 77mm UV Tiffen filter now just $10!
Can't get any cheaper anywhere.
Forum: Sold Items 04-14-2008, 06:51 PM  
For Sale - Sold: FS: DA 40mm f/2.8 Limited; Hoya, Tiffen filters
Posted By zaurus
Replies: 4
Views: 2,904
PM replied, sale of DA 40mm + HMC 30.5mm filter pending... SOLD.
Tiffen 77mm filter still available.
Forum: Sold Items 04-13-2008, 04:42 PM  
For Sale - Sold: FS: DA 40mm f/2.8 Limited; Hoya, Tiffen filters
Posted By zaurus
Replies: 4
Views: 2,904
1. DA 40mm f/2.8 Limited lens.
SOLD

2. Hoya HMC UV 30.5mm filter.
SOLD

3. Tiffen 77mm UV filter.
SOLD
Forum: Photography Articles 04-06-2008, 01:45 PM  
Complete color management and workflow under Linux -- from a Pentax user
Posted By zaurus
Replies: 14
Views: 16,809
I myself am using openSUSE 10.3 for my workstation.
One of the reasons is the excellent package manager, YaST, and the vast choice of community repositories for free high-quality softare.

You don't need to build ArgyllCMS (as per Joel Cornuz's original post) under openSUSE!
A ready constantly updated package exists.
Just add in YaST with copy/paste this repository:





Code:

http://download.opensuse.org/repositories/home:/hfiguiere/openSUSE_10.3/



Get from the same repository also RawStudio (raw converter) [1], PhotoPrint (print manager) and Lprof (ICC profiler).

Also, get CinePaint (retouching) and Oyranos (its color management system) from:





Code:

http://download.opensuse.org/repositories/home:/bekun/openSUSE_10.3/



Get Xcalib (monitor calibration loader) and Scribus (desktop publishing) from:





Code:

http://download.opensuse.org/repositories/home:/mrdocs/openSUSE_10.3/



All excellent tools, some have no equivalent under any other operating systems!


[1] RawStudio and Digikam utilize LittleCMS instead of ArgyllCMS.
Forum: Photography Articles 03-30-2008, 07:32 PM  
Complete color management and workflow under Linux -- from a Pentax user
Posted By zaurus
Replies: 14
Views: 16,809
Joel Cornuz, a Pentax DS user from Switzerland, maintains a very informative blog on most aspects of digital photography under Linux:
Linux Photography

I recently followed one of his write-ups to calibrate my monitors (Eizo L887 and L685) with the Spyder2 using the open-source ArgyllCMS:
Use Colorvision Spyder to produce an ICC monitor profile under ArgyllCMS

The result is very good, by far outperforming the one achieved with the Express Mac/Win software.

Highly recommended.
Forum: Pentax SLR Lens Discussion 03-30-2008, 07:14 PM  
Which Pentax-branded lenses are based on third-party (optical) design?
Posted By zaurus
Replies: 29
Views: 5,478
So the opinions of what this "cooperation" or "co-design" might be, range from actually working together on a new design to copying an existing one and everything in-between?
And there are no facts to prove one way or the other?

OK, let's assume for a moment this "cooperation" is for a new design.
Did Tokina and Pentax work as equal partners during all phases of the inception, initial design and subsequent development?
Or maybe one of them was primarily responsible consulting the other one only when needed/desired?

Here is a simple observation.
To my knowledge, the only lens Pentax has officially acknowledged to have co-developed and co-designed is the smc PENTAX DA FISH-EYE 10-17mm F3.5-4.5 ED [IF].
AFAIK, this is the only lens Pentax has announced and delivered before the Tokina's version of it, on November 30th, 2005.
Tokina announced their lens 7 months later.
Tokina might have delayed their version of the lens because they need to account for two mounts, not one.
Or maybe because the bulk of the initial design was done by Pentax so they were ahead to start with.

In any case, since then it is Tokina who first and well ahead announces and delivers the supposedly "co-designed" lenses, not Pentax.
And Pentax does not claim "co-design" anymore.

So I would guess that with the exception of the fish-eye, Tokina is the primary designer of the common lenses.
Pentax probably participates with just consulting (if anything at all) in the initial design.

Why is that important to me?
For a number of reasons, only one of which is to predict future Pentax offerings.
Far important is that (as it is well-known), Tokina designs its lenses independent of a particular mount.
The answer to what extent this "one size fits all" approach limits performance enhancements for any particular mount (including the K mount) -- I will rather leave to the experts in optical design here.

However, that such performance limitations exist, might be the reason why the new DA* 16-50mm f/2.8 did not bring the expected better performance on comparable features over the Pentax originally designed DA 16-45mm f/4.
Forum: Pentax SLR Lens Discussion 03-25-2008, 11:47 PM  
Which Pentax-branded lenses are based on third-party (optical) design?
Posted By zaurus
Replies: 29
Views: 5,478
Extensive search did not reveal definitive answer save for the 18-250mm publicly acknowledged to be a rebadged Tamron.

Are among these:

DA 10-17mm
DA 12-24mm
DA 14mm
DA 35mm Macro Limited
PENTAX-DA* 16-50mm f/2.8 ED AL[IF]SDM
smc PENTAX-DA* 50-135mm f/2.8 ED AL[IF]SDM
smc PENTAX DA 18-250mm F3.5-6.3 ED AL [IF]

Yes/no, any others?

Nothing implied, just getting the record straight.
Forum: Pentax News and Rumors 03-15-2008, 02:24 PM  
Any rumours for next generation camera yet?
Posted By zaurus
Replies: 20
Views: 7,417
Is this info based on some reliable source or simply yours (and mine) desire?

Because this interview with John Carlson, Product Manager Imaging Systems, Pentax USA, on the last day of the PMA 2008 does not support it.
Forum: Pentax News and Rumors 03-05-2008, 05:46 PM  
Olympus E-420 is what K200d should have been
Posted By zaurus
Replies: 40
Views: 8,785
I want a camera which is always with me as part of my lifestyle, just like my watch, PDA and home/car keys.
I don't want to specifically think "Now I am going out to take pictures hence I should not forget the camera."
I want the camera to be an extension of my vision, taking of pictures to be automatic the same way I open a door.

Until now, compact digicams simply did not have the minimum IQ/features.
Sigma DP-1 was promising but they screwed it up.
Pentax had the pancakes.
Olympus the small bodies.

The new Olympus pancake changes the game completely.
Now for a first time it seems to be possible to go as light as one wants up to semi-professional -- in one system.

If Pentax does not come up with a body matching the pancakes this year, I am sure they will lose not only me.
Forum: Sold Items 03-04-2008, 10:19 PM  
For Sale - Sold: FS: 18-55mm f/3.5-5.6 kit lens and 52mm filter 3-piece set
Posted By zaurus
Replies: 5
Views: 3,163
Filter set is sold.
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