Go Back   Steve's Digicams Forums > Digital SLR and Interchangeable Lens Cameras > Pentax / Samsung dSLR, K Mount Mirrorless

Reply
 
Thread Tools Search this Thread
Old Feb 5, 2008, 1:28 PM   #1
Member
 
Join Date: Oct 2007
Posts: 44
Default

Hi everybody,

As some here might have observed, i am a wannabe pentaxian. Been on this forum since late last year and still dream to own a K10D in the near future.

I had already started a thread where i introduced myself and also asked for a lot of purchasing advice, but what i want to know now would actually help everybody here in the forums and so decided to post a different thread altogether.

Please find below the thread i am referring to .
http://forums.steves-digicams.com/forums/view_topic.php?id=581100&forum_id=80

Three months down the lane, i see myself holding the camera and taking the first trial shots which would begin an exciting learning time for me. Hence my seriousness at trying to figure out the possible purchase route and the Bill Of Material for which i asked for relevant advice in the below thread.
http://forums.steves-digicams.com/forums/view_topic.php?id=585657&forum_id=80

To be frank, the point where i loose clarity is when it comes to lenses. I've tried a lot on google for an updated naming convention for the Pentax range of lenses but could not find any. So, this is my try at wanting to understand the conversation that happens here between you experts, with and without LBA

I was referring to adorama.com as per ishino's suggestion. So, i base my entire effort on the data presented in that website.

Find below a compilation of ALL the pentax lenses on sale right now, with their prices in USD.


Now, i just put up a simple filter and am presenting to you the unique records in every category.




Applying the same logic of filtering out the unique entries, find below the various descriptions used in combination with the lens naming.



I request the lens experts to put in what ever is possible so that we could have a clear picture of what's on the market and what does pentax mean by that.

Being a n00b here, i'll ask the first set of questions.
1) When i see that there is only one focal lenght specified, say... 35mm... are these the lenses you call as 'Prime Lenses'?
2) With reference to the second screen shot... what do the codification mean ie., what's SMCP, DA, DA*, FA etc.
3) With reference to the third screen shot... what do the text descriptions mean? ie., what's the difference between Auto Focus Lens, Auto Focus Zoom Lens, Limited Edition etc?

Any suggestions for changes toimprove thepost is very welcome. I could attach the excel sheet if anybody finds it useful.


no_nonsense4857 is offline   Reply With Quote
Sponsored Links
Old Feb 5, 2008, 2:02 PM   #2
Senior Member
 
bilybianca's Avatar
 
Join Date: Nov 2005
Location: Hassleholm, Sweden
Posts: 3,435
Default

Hi NN

Of course we have to start with Compulsary School: http://www.bdimitrov.de/kmp/index.html. What you cannot find here about Pentax K-mount is futile and irrelevant. For your specific topic there is http://www.bdimitrov.de/kmp/technology/lens_terms.html

But if I try as far as I can right here someone else can fill in gaps, omissions and correct my errors

Prime lens: a lens with only one, fixed focal length. Usually higher picture quality than a zoom covering the same length. Also "faster", meaning a larger maximum aperture allowing shorter exposure time.

Normal lens: A prime lens with a focal length around 50 mm, giving approximately the same angle of view as the naked eye on a "full frame" 35 mm film camera. On a digital SLR 35 mm is more of a normal lens.

WA, Wide (angel): A lens with a short focal length, giving a wide perspective bringing in more into the frame from the sides.These lenses are suitable for taking photos in small rooms and for landscape photography.

Tele: A lens with along focal length, bringing the subject closer to the photographer. Suitable for sports and wildlife. Short teles are also very popular for portraits.

Crop factor: Many photo enthusiast have grown accustomed to the viewing angel the lenses ofvarious focal lengts have when used on an older film camera. When a lens of a certain focal length is used on a digital camera it gives less angel of view, like if it was 1.5 times longer than when the same lensis used on a film body. Thus many photographers refers to this as "the crop factor, making a 50 mm lensbecome 75 mm lens". This is not correct, 50 mm is always 50 mm, but still it gives you a hint of what you can expect from a specific lens. 50 mm is a "normal" on a film body, but becomes a "short tele" lens on a digital.

Zoom lens: A lens with variable focal length, ie 35–70 mm

Standard: A zoom lens which covers the "normal" focal lenght, like 35–70mm or 18–55 mm on a digital body. Often the "kit lens" sold with the camera body.

Auto focus lens: A lens that works with the camera body's auto focus system. Just press the exposure button half ways and the camera focusses the picture.

Manual lens: Normally referring to the lens lacking the auto focus feature. Thus you have to turn the focus ring on the lens as you check thesharpness through the viewfinder. The term can also refer to theaperture having to be stopped down manually with the ring on the lens. "Fully manual" refers to the lens both being manually focused and requireing manually setting of theaperture.


SMC: Super Multi Coated. A special coating is applied to the front lens to minimize flare and reflections. Pentax is widely recognized for the SMC, considered the best coating any maker can deliver.

SMCP: I don't know what the P stands for. Anyone? Is it simply Pentax?

M42: Pentax screw mount lenses, can be used on bayonet mount cameras with an adapter.

K: The Pentax K-mount, the original bayonet mount

M: A fully manual lens, manual focus and manual setting of the aperture (no electrical contacts). Basically the same as K

KA: A development o fthe K/M lens mount, adding electrical contacts that allows communication between body and lens. On the lens' aperture ring an "A" setting is added. With these lenses the camera body's programmed exposuremodes, and theTV mode, can be used. Manual focus.

F: Pentax's first auto focus series, including all the goodies from the "A" series and auto focus above that.

FA: Yet another step, adding more communication between lens and body, and with some zoom lenses also the motor driven "Power Zoom".

FA Limited: A series of three top quality lenses, just taken out of production.

FA-J: A series of only two zoom lenses, where the manual aperture ring on the lens is missing.

DA: The most recent series, like the FA-J but with coatings on both front and rear lens, and optics that cover a smaller area (the digital sensor is smaller than the analog film frame).

The Green Star *:M*, A*, F*, FA* and DA* indicates that this is a lens of highest quality, optically as well as mechanically. Nowadays found at higher prices than when they were sold new (except the DA*, which are sold new now.)


Kjell








bilybianca is offline   Reply With Quote
Old Feb 5, 2008, 2:02 PM   #3
Senior Member
 
Monza76's Avatar
 
Join Date: Jul 2004
Posts: 4,095
Default

no_nonsense4857 wrote:
Quote:
1) When i see that there is only one focal lenght specified, say... 35mm... are these the lenses you call as 'Prime Lenses'?
2) With reference to the second screen shot... what do the codification mean ie., what's SMCP, DA, DA*, FA etc.
Any suggestions for changes toimprove thepost is very welcome. I could attach the excel sheet if anybody finds it useful.
Quote:

#1 Yes single focal length = prime.

#2 SMCP literally "Super Multi Coated Pentax" although the actual company designation may be different. All premium Pentax branded lenses should have SMC in the label (some older A and F series lenses were economy models without the SMC designation.

K-mount lenses are roughly divided into:

M miniature, the smaller manual focus lenses introduced in the 1970s with the M-series cameras.

A automatic aperture, allowed shutter priority automation, introduced in the 1980s for the A-series cameras (and the later P series). These lenses had the "A" setting on the aperture ring.

F the first autofocus series of Pentax lenses (no comments on the ME-F please), introduced with the SF series cameras in the late 1980s

FA full framefilm lenses with an aperture ring, still suitable for digital.These lenses came along with the MZ/ZX cameras. Some werepower zoom models for the PZ series cameras (and the higher end MZ/ZX models).

D-FA digitally optimized but still usable on a film SLR, still has an aperture ring.

FA-J an FA lens with no aperture ring.

DA digital only lens, will vignette if used on a film camera, no aperture ring.

DA* digital only with highest quality glass and SDM (focus drive motor in the lens for K100D Super, K10D, K200D and K20D, there is still allowance for in-camera AF drive on older models), these are usually the best Pentax lenses (possibly except for the limiteds)

Limited, the compact FA and DA primes that areof exceptional mechanicalquality and well above average optical quality. The DA* lenses cover zooms and long focal length primes, the "Limited" series cover shorter primes and (unless that changes soon) they do not have SDM drive.

Hope that helps, check out: http://www.bdimitrov.de/kmp/index.html it is the source of lots of technical data.

Ira

Oops, Kjell beat me to it.

Monza76 is offline   Reply With Quote
Old Feb 5, 2008, 10:01 PM   #4
Senior Member
 
NonEntity1's Avatar
 
Join Date: Jul 2006
Location: Lake Placid Florida USA
Posts: 2,689
Default

"FA Limited: A series of three top quality lenses, just taken out of production"

They are out of production? I had not heard that. This is not good, I have not saved enough money yet for even one of the two I want!

Tim
NonEntity1 is offline   Reply With Quote
Old Feb 5, 2008, 10:20 PM   #5
Senior Member
 
ishino's Avatar
 
Join Date: Oct 2006
Posts: 661
Default

i had not heard of that either tim. humm... looks like the fa 31 is going to have to be my next purchase. b&h still has all 3 in stock.
ishino is offline   Reply With Quote
Old Feb 5, 2008, 10:39 PM   #6
Senior Member
 
snostorm's Avatar
 
Join Date: Jan 2004
Location: Chicago Suburb, IL, USA
Posts: 2,770
Default

Hi Sai,

I'll add a few of the terms that are used in the lens descriptions that haven't been covered yet.

AL= Aspheric Lens -- this means that the design includes at least one element that not ground to coform to the arc of a circle. These are generally used to make the lens more compact, and are harder and more expensive to produce.

(IF)= Internal Focusing -- this means that the focusing is accomplished internally, and therefore the lens doesn't change length when focused at different distances. It has the added benefit of not rotating the front element, so it's easier to use a polarizing or graduated neutral density filter with.

ED= Extra Low Dispersion -- This means that at least one element is made of special low dispersion glass. It's also called Apochromatic (APO), Super low Dispersion (SD), and Low Dispersion (LD) by different manufacturers. Essentially this means that the lens was designed to control Chromatic Aberrations (CA) -- color fringing that is caused by the different frequencies in the light being bent at different rates -- the best example of this is the rainbow created by a prism (or, I guess a rainbow. . .duh :-) ).

Low Dispersion glass lessens the difference between the angles of diffraction, thus cutting down the fringing. Even among ED (or SD, LD, or APO -- take your choice) lenses, you'll find different degrees of CA control, so this does not mean that such a lens will be CA free -- so you takes your chances. . . but realize that ED glass is extra expensive, so lenses with these elements will usually perform better in general as manufacturers probably won't design ED glass into mediocre designs.

Another feature that a few Pentax lenses had was PZ whch is Power Zoom. This had a separate motor in the lens which operated the zoom. There were a bunch of special functions in the PZ series of film bodies, but these don't apply to DSLRs (at least I don't think. . .)

Scott
snostorm is offline   Reply With Quote
Old Feb 6, 2008, 12:52 AM   #7
Senior Member
 
bilybianca's Avatar
 
Join Date: Nov 2005
Location: Hassleholm, Sweden
Posts: 3,435
Default

NonEntity1 wrote:
Quote:
"FA Limited: A series of three top quality lenses, just taken out of production"
I too hope this information is wrong, can't find the source right now but I'll try to check it up later. Bojidar Dimitrov was fortunately wrong about the FA50 mm 1.4, which according to his page was taken out of production already in 2004.

Kjell
bilybianca is offline   Reply With Quote
Old Feb 6, 2008, 9:25 AM   #8
Member
 
Join Date: Oct 2007
Posts: 44
Default

Thank you very much.... all of you.

My next doubt would be regarding the DA and FA lenses.

You see the DA has 'less' glass given that it needs to take care of less sensor area when compared to a 35mm film area. Given this case, how do i logically relate to the mouth watering price of the SMCP-FA 50mm f/1.4 for only USD 200? In other words, what are the trade offs between choosing a DA series and the FA series?


I ask this because, i plan to buy the SMCP-FA 50mmalong with the kit lens. Then i'll be broke enough so that the LBA (n00bs dont need LBA though :-)) is out of question until i learn to take decent photoes.

Why does a lens being 'macro' enabled push up the price. Does it need a lot of extra to get the focusing distance to a much closer range?

no_nonsense4857 is offline   Reply With Quote
Old Feb 6, 2008, 12:37 PM   #9
Senior Member
 
bilybianca's Avatar
 
Join Date: Nov 2005
Location: Hassleholm, Sweden
Posts: 3,435
Default

I'm not sure wether you think the advantage is on the FA or DA side. If I have understood it correctly, the only difference between "digital" lenses versus "analog" lenses is that the DA lenses have an anti-reflex coating also on the rear element, to take care ofpossible reflexes from the sensor. My only "digital" lens is the kit lens, and I have never experienced any problem with ghosts or flare of this kind with any of my pre digital ones. I have M, A, F and FA lenses.

There is one advantage with older lenses, designed for full frame. All lenses are best in the centre, the corners being less sharp, with vignetting problems (darker corners) or distortion (straight lines such as house corners being curved in the picture). When used on digital bodies these edges are cropped away already from the beginning. The sensor only uses "the sweet spot" of the lens. The difference is bigger with ceaper low quality lenses since they more often have these edge problems. (To design lenses so these problems are minimized is what makes them more expensive.) Thus a less stellar A/F/FA lens can become a really good one when used on a digital body.

I'm not sure why macro lenses are generally more expensive, but one reason might be that there aren't any poor quality macro lenses on the market. I've got the impression that they are all very good. Maybe because macro lens buyers are often advanced amateurs or pros, who are very concious of what they buy and they only want HQ.

I can fullheartedly recommend the FA50mm 1.4. Those who know my lens setup can confirm that I'm one of those demanding lens buyers.

Kjell
bilybianca is offline   Reply With Quote
Old Feb 6, 2008, 1:15 PM   #10
Senior Member
 
penolta's Avatar
 
Join Date: Apr 2007
Location: California USA
Posts: 5,206
Default

The descriptive terminologies used arenot always clear, but there is a difference between "Digital" and "Digital only" lenses. Lenses designed for the 35mm format project a larger circle of light to the film/sensor plane because the full frame format is larger than the APS-C size chip used in manyDSLRs (including Pentax). The smaller circle of light that encompasses the APS-C sensor chip allows less glass to be used, hence lenses of similar specifications can be smaller and lighter. Full frame "digital" lenses can be used on both SLRs and DSLRs, but "digital only" lenses can only be used on DSLRs. "Digital coatings" are applied to either format lens if intended for use on DSLRs, as they are supposed to increase the performance of the lens with a camera having a digital sensor.
penolta is offline   Reply With Quote
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 9:45 AM.