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04-14-2015, 12:49 PM   #826
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QuoteOriginally posted by ChristianRock Quote
What lenses are they backward engineering?

I mean, how is that different from all the double gauss lenses out there? Isn't everybody copying Zeiss with their primes? And didn't Angenieux invent the retrofocus wide angle lens in 1950, and isn't every SLR wide angle lens now derived from that concept?

Or am I understanding it incorrectly and is Sigma actually infringing copyrighted designs?
From what I understood the basic designs for lenses including invert telephoto is far older than that. Retrofocus is more a specific version of it.

04-14-2015, 12:57 PM   #827
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Reverse engineering in lenses refers to the communication protocols that the body and lens use to optimize operation. Either you license the protocols, or reverse engineer them. Essentially you buy knowledge that you otherwise have to figure out yourself.

The desktop computer industry was built starting with Compaq reverse engineering the IBM bios. The bios source code was published but copyrighted, so Compaq had programmers who had never seen the code but had access to the system call details and built a bios that was equivalent to the IBM one. Others did the same, reverse engineering the expansion card bus and other hardware details, and an industry was born.

I think that Pentax Ricoh would be better off publishing the api's and encouraging vigorous third party support for their wares, but that isn't the Japanese way.
04-14-2015, 01:05 PM   #828
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QuoteOriginally posted by Rorschach Quote
I am not claiming that it is illegal it is just something that I will not support.

It is part of a larger thing actually: every time you buy something, you essentially cast a vote, support some approach, agenda, philosophy, business ethic etc.

I guess this sort of thinking comes naturally if one makes the active choice of trying to live supporting sustainability...we buy our house electricity from wind power companies even though it is more expensive than regular electricity, buy local and organic food items always when possible and so on...
Reverse engineering is considered as key for the developement of the human civilization to not block/prevent other from innovating. Preventing you product to work simelessy with other products just prevent innovation and progress.

In an advenced world like us you never make anything completely new, you typically improve a tiny bit over existing things or just use them in a different context.

The spirit is that nobody can copy exactly your camera, and sell it. You are protected from that. Also if you really inovate and implement a real novel idea, patents are there to protect your hard investment. By definition if you agree to file a patent everybody that pay can copy the idea legitimaly.

In case of technical details like a lense mount the main goal of having your own if for protecting your market, prevent other to build on top of the echosystem and not to protect any innovation you really made. Because lenses and camera are different products, it is counterproductive to prevent any lense from being used on any camera.

It so permited to reverse engineer the mount protocol so you can make your lense work on any camera like it should be.

Beside, if you don't like reverse engineering, never use for example an Android phone. The Java API that at the core of Android has been reverse engineered by Google. In fact it is likely that if you never accepted reverse engineering you should never buy generics, and even among brand product you may find that most are not suitable. The fact that you don't know the specific story of each product you use doesn't make them better.
04-14-2015, 01:19 PM   #829
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Sigma is an obvious one and others are not so should I use my money to support to Sigma just because other companies do or might do the the same...no. By all means, keep buying Sigma but I'll pass. Easy pass too, just as easy as giving the boot to Facebook about ten years ago :-)

04-14-2015, 01:27 PM   #830
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QuoteOriginally posted by Rorschach Quote
Sigma is an obvious one and others are not so should I use my money to support to Sigma just because other companies do or might do the the same...no. By all means, keep buying Sigma but I'll pass. Easy pass too, just as easy as giving the boot to Facebook about ten years ago :-)
Heck, I have avoided Sigma lenses because of their immense size, weight and flare problems. But in light of this new 70-200 and the 150-450 I guess I might need to recalibrate that whole size/weight portion of the equation.
04-14-2015, 01:57 PM   #831
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QuoteOriginally posted by Quicksand Quote
Heck, I have avoided Sigma lenses because of their immense size, weight and flare problems. But in light of this new 70-200 and the 150-450 I guess I might need to recalibrate that whole size/weight portion of the equation.
It was funny reading a while ago about how that happened. The Sigma engineers would always come in their bosses and say "if you just let us make it this much bigger, we can add this and this and this feature to it"... and they just got bigger and bigger.
04-14-2015, 03:32 PM   #832
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QuoteOriginally posted by normhead Quote
It was funny reading a while ago about how that happened. The Sigma engineers would always come in their bosses and say "if you just let us make it this much bigger, we can add this and this and this feature to it"... and they just got bigger and bigger.
Yeah, I remember reading an interview with a Sigma exec who said he was proud of what his engineers achieved once they were told weight wasn't an important concern.
04-14-2015, 03:50 PM   #833
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QuoteOriginally posted by derekkite Quote
Reverse engineering in lenses refers to the communication protocols that the body and lens use to optimize operation. Either you license the protocols, or reverse engineer them. Essentially you buy knowledge that you otherwise have to figure out yourself.

The desktop computer industry was built starting with Compaq reverse engineering the IBM bios. The bios source code was published but copyrighted, so Compaq had programmers who had never seen the code but had access to the system call details and built a bios that was equivalent to the IBM one. Others did the same, reverse engineering the expansion card bus and other hardware details, and an industry was born.

I think that Pentax Ricoh would be better off publishing the api's and encouraging vigorous third party support for their wares, but that isn't the Japanese way.

Absolutely. More 3rd party support builds a stronger system. The lack of support from 3rd party lens manufacturers actually hurts the K-mount in the eyes of some. Some times those "backwards" engineered solutions work better than the original. I'll buy HSM over SDM. Everything I own is screw drive or HSM. I have avoided SDM. I'm looking forward to the new DC lenses.

04-14-2015, 07:19 PM   #834
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where are the 2x & 3x TC hiding

QuoteOriginally posted by Stavri Quote
I know folks here want the 600 f4, 250-600 etc but the 300mm f2.8 is the classic focal length, perfect lens for wildlife/birding, you can put on different TC's and get 420, 600, 900mm 1-3 stops down. Seeing how much mileage people have gotten from their DA* 300 + TC, the new 300mm f2.8 from Pentax will be a showstopper.
yes you can put on the new HD 1.4TC,but where are the 2x & 3x ones that will do justice to this lens? much rather have a 500 F4.5 with 1.4TC in Pentax quality
04-14-2015, 08:21 PM   #835
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QuoteOriginally posted by Shanti Quote
yes you can put on the new HD 1.4TC,but where are the 2x & 3x ones that will do justice to this lens? much rather have a 500 F4.5 with 1.4TC in Pentax quality
IMHO, TC over 1.4 or 1.5x are not worth it...
We saw however someone here that stacked two 1.4x HD TC on a DA560mm, and the results were pretty good ... better that I thought... so maybe if Pentax makes a 2x HD TC with the same optical quality of the new 1.4x HD TC that would be worth it... Otherwise, I'd also prefer have a 300mm f2.8 and a 500mm or 600mm f4 in the lineup and use the 1.4x HD TC...


As for a new 250-600mm...yeah, we can dream, but the FA is 5,8 Kg for the lens only, I cant imagine a 250-600mm f4 would weight !
04-15-2015, 12:26 AM   #836
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QuoteOriginally posted by Winder Quote
Absolutely. More 3rd party support builds a stronger system. The lack of support from 3rd party lens manufacturers actually hurts the K-mount in the eyes of some. Some times those "backwards" engineered solutions work better than the original. I'll buy HSM over SDM. Everything I own is screw drive or HSM. I have avoided SDM. I'm looking forward to the new DC lenses.
HSM motor has nothing to do with SDM motor. We all know this, fortunately for Sigma (and unfortunately for Pentax). The protocol used for lens comminication though is essential. If Sigma does not pay license, Sigma did reverse engineer that communication protocol. Same for other mounts.

And thos does not in any way change a thing about the (vast) superiority of HSM motor vs SDM motor.

Btw, afaict, Sigma HSM motor predates (2005 ? ) Pentax SDM motor (2007).
04-15-2015, 04:57 AM   #837
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QuoteQuote:
I know folks here want the 600 f4, 250-600 etc but the 300mm f2.8 is the classic focal length, perfect lens for wildlife/birding, you can put on different TC's and get 420, 600, 900mm 1-3 stops down. Seeing how much mileage people have gotten from their DA* 300 + TC, the new 300mm f2.8 from Pentax will be a showstopper.
I disagree, I'm not satisfied with my 300 f4 + TC combo, I only use the TC when I can't avoid it. So I would really prefer a 500 f4 over a 300 f2.8, as we already have a 300 (and a very good one ). Of course, the best would be a 300 f2.8, a 500 f4 and a 600 f4, to have the choice ! But after that some guys would complain the lack of a 800 f5.6 :/
For the 250-600, well the 150-450 on an APSC is equivalent to a 225-675, so...
04-15-2015, 08:40 AM   #838
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QuoteOriginally posted by timautin Quote
I disagree, I'm not satisfied with my 300 f4 + TC combo, I only use the TC when I can't avoid it. So I would really prefer a 500 f4 over a 300 f2.8, as we already have a 300 (and a very good one ). Of course, the best would be a 300 f2.8, a 500 f4 and a 600 f4, to have the choice ! But after that some guys would complain the lack of a 800 f5.6 :/
For the 250-600, well the 150-450 on an APSC is equivalent to a 225-675, so...
The Da* 300 + 1.4x Tc seems to produce better results than the Bigma 50-500 on the long end, from the comparison on this thread
04-15-2015, 09:05 AM - 1 Like   #839
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I can crop K-3/DA*300/1.4X images to pixel level and maintain sharpness. I shoot BIF with this combo frequently with high success rates. I don't know what more anyone could ask.
04-15-2015, 09:40 AM   #840
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QuoteOriginally posted by timautin Quote
I disagree, I'm not satisfied with my 300 f4 + TC combo, I only use the TC when I can't avoid it. So I would really prefer a 500 f4 over a 300 f2.8, as we already have a 300 (and a very good one ). Of course, the best would be a 300 f2.8, a 500 f4 and a 600 f4, to have the choice ! But after that some guys would complain the lack of a 800 f5.6 :/
For the 250-600, well the 150-450 on an APSC is equivalent to a 225-675, so...
QuoteOriginally posted by Stavri Quote
The Da* 300 + 1.4x Tc seems to produce better results than the Bigma 50-500 on the long end, from the comparison on this thread
QuoteOriginally posted by audiobomber Quote
I can crop K-3/DA*300/1.4X images to pixel level and maintain sharpness. I shoot BIF with this combo frequently with high success rates. I don't know what more anyone could ask.
I have posted, several times now, that I am not getting what others report in terms of IQ when using the DA*300/4 and the HD 1.4X TC.
This could well be my own fault: technique, settings, fine AF adjustment ... whatever.
Then again, I am still using my good old K5; could be a different game with the K3, I have no idea.
Some time ago, I was considering the Sigma 500/4.5 but the price took me back to reality.

I am so looking forward to this new 150-450 lens, hoping it will have the IQ of the 300/4 (wishful thinking?) without a TC, of course.

Edit: my bad .... my reply should be in "the other thread" !

Last edited by jpzk; 04-15-2015 at 11:34 AM. Reason: added info
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