[8540tomg]

Hi all,

There is a K 300 thread running concurrently with this one. You may or may not be following it. In any case a member (Daniel) suggested that a 2x converter would not work with the K 300.




I took Daniel’s challenge and used the following combination of gear: Pentax K10, Pentax Rear Converter K T6-2X, and monopod in conjunction with my K 300mm f 4 lens. The 2x converts the K 300 to roughly a 900mm f8. Depth of field is non- existent with the 2x attached. Focusing is difficult and if you breathe heavily your subject disappears and dances out of the frame. I think my heartbeat knocked it around a bit too. As a result 99% of the shots were trash. I only spent half an hour and if time allowed I might have done better. In any case the three remaining shots were the best I could do today with this rig. The chickadees are a bit out of focus. The red wing blackbird is a little better. I like the bokeh in this shot. Not exactly ready for National Geographic are they Daniel? I’m not ready to concede it is impossible to get a good shot with this combo but it will be difficult. No post processing with any image. This is the way they came out of the K10. I think I might have better luck with the tripod. I’ll give that a go when I get some more time.







Thoughts?

[monochrome]

Nice shots - just goes to show what manual lenses and patience can yield. Do we get addicted to autofocus?

I've wanted a bit more reach than I get with my K200/4 - but I forget that I have a K T6-2X in a box in my closet (thanks for the reminder) so a T-converter will qualify for this thread!!

Throughout this forum I have read that converters above 1.4x subject IQ to significant degradation - time to discover if that applies only to modern lenses.

After I finish washing windows, out comes the tripod!!

[8540tomg]

Thanks Monochrome. The 2x does give that added reach. I think 900mm is long enough for most shots. Shake reduction works but I suspect using a tripod is a necessity for this ultra telephoto length as all the books will tell you. The slightest shake with this monster really has an impact on the image. In any case it is fun working with this sort of length. Looking forward to your 2x shots.

Tom G

[AML]

I don't have any K lenses, but i've thouroughly enjoyed seeing everyones pics so far.

[TourDeForce]

Anne, you MUST spend enormous sums of money on a manual lens! You MUST!! Get out your $40 and spend it NOW!

[frank]

K135/2.5 - one of the best manual lenses I've had so far:

[deudeu]

Wow Frank! Those black and white shots are intense!
Love your pictures!

[Piotr]

I will continue this thread with my few SMC K lenses:

Pentax *ist DS ,Pentax smc 24mm f/2.8 1/350s iso200


Pentax *ist DS ,Pentax smc 30mm f/2.8 1/4000s at 30.0mm iso400


Pentax *ist DS ,Pentax SMC 50mm 1:1.2 1/160s f/2.8 at 50.0mm iso200


Pentax *ist DS ,Pentax smc 135mm f/2.5 1/125s iso400


Pentax *ist DS ,Pentax smc 500mm f/4.5 1/1500s iso200

[8540tomg]

Hi all,

Frank – Good work with that K 135/2,5. It is clearly in good hands.

Piotr – Nice collection of Ks there. You have most of the ones I always wanted. Based on your shots and Franks the K 135/2.5 appears to deserve its reputation. I would like to see more shots from the 500 4.5.

Is it my imagination or do the K series lenses have a slighter different colour cast to them than the M series? Could it be the earlier version of the SMC coating? Thoughts?

Tom G

[morfic]

Ok, so what's the difference between K and M? Both have a K bayonet, both are Manual and don't have the Automatic aperture?

[jsherman999]

Right - also, different optical designs for many (different element groupings, etc). The M's were designed to generally be smaller/lighter than the K's. Most people feel that in general, the K's are superior because of this, but I think that's only true in specific cases (K 135 2.5, for example.) IMO, many of the M's show equal IQ to their K counterparts. But this is based on my extensive use of M's and my limited testing and research into K's - I could prove myself wrong the more I acquire/use K's (but I doubt it.)

A good place to research the differences in the lens lines: ---> Pentax K-Mount Lenses and Lens Accessories

[hinman]

Right - also, different optical designs for many (different element groupings, etc). The M's were designed to generally be smaller/lighter than the K's. Most people feel that in general, the K's are superior because of this, but I think that's only true in specific cases (K 135 2.5, for example.) IMO, many of the M's show equal IQ to their K counterparts. But this is based on my extensive use of M's and my limited testing and research into K's - I could prove myself wrong the more I acquire/use K's (but I doubt it.)

A good place to research the differences in the lens lines: ---> Pentax K-Mount Lenses and Lens Accessories

Jay, you have outstanding photography. Any M lens in your possession will turn up a notch like a limited or a K version if the K turns out to be better.

But I do hear more people praising on the K. For instance, the 200mm on the K is noted by others better than the M version. And similar goes into 100mm F/4 macro 1:2. I tend to think only minor IQ and not by much, but having seen so many good pictures from both M and K, I would assume that both are just as nice and very similar in IQ, but if I am given similar offer on both K and M lens, I would jump on the K.

Regards,
Hin

[hinman]

I have two K lens

Pentax 100mm f/4.0 Macro 1:2





Pentax 45-125 f/4.0

[8540tomg]

Morphic,

The K series were introduced in 1975 for use with the K family of camera bodies. This marked the end of the Pentax screw mount era. Most of these K series lenses, according to Danilo Cecchi in his book Asahi Pentax and Pentax SLR 35mm Cameras 1952-1989, were based on the renowned SMC Takumar designs. “The optical units of the SMC Takumar lenses were assembled on bayonet mounts and reintroduced onto the market under a different name.” (Cecchi, 181) If you glance though the site’s lens database you will find some of the finest Pentax glass: the 85mm 1.8, 135/2.5, 200/2.5 and 15/3,5 for example were part of this generation.

Physically, the K series are quite a bit larger and heavier than their M series counterparts. They are all metal in construction as are the M series. Most M series lenses were entirely new optical designs however. Danilo Cecchi notes the “optical layouts for the M series were the result of “careful study and sophisticated computer calculations.” (Cecchi, 184). Computer design in the mid 1970s was a pretty new idea. The M series, as a rule, has not been as highly regarded as the K and later A series for some reason. I don’t believe this to be true as the M Club has demonstrated in this forum but the perception is out there IMO.

By 1980 the smaller, lighter M series camera bodies (MX, ME Super, MV etc.) and lenses had pretty much replaced the K series. All manufactures were producing smaller and lighter equipment by this time led by Olympus.

Both the K and M series had SMC coatings but the coating formula seems to change from time to time. It appears to have a bluish cast on most SMC K lenses but on some others, my M 35mm f 2 it has a slight magenta cast.

In any case as I look at shots from the K Club it seems to my eye the images have a slightly differ look to them than M series glass. It may be the result different lens coatings or optical designs but I think they have a different look. It probably doesn’t really matter as they all look pretty good to me


Cecchi, Danilo. Asahi Pentax and Pentax SLR 35mm Cameras 1952-1989. Hove : Hove
Photo Books, 1990.

This book suffers a bit in the translation from the Italian but provides a good history of Pentax lenses and cameras from the early 1950s through 1989. The Wikipedia article draws heavily from this source.

Pentax - Wikipedia, the free encyclopedia

Hope this helps.

Cheers,
Tom G

[Lowell Goudge]

Ok, so what's the difference between K and M? Both have a K bayonet, both are Manual and don't have the Automatic aperture?

aside from smaller and lighter, which some people like and others don't (I call it the M disease because the cameras were too small for me to hold), some M series lenses I have used seem to have a different feel, principally that the focusing drag does not seem as positive and consistent as the K series. I posted once before they feel "cheap" but can''t really explain it.

The biggest thing was pentax tried to standardize as much as possible on 49mm filters, and many M series lenses got 1/2 to 1 stop slower than the K series counterparts as a result of the reduced diameter.