Using K mount third-party lenses on the K100D...

[The PIPE]

Dear Fellow Pentaxians:

The PIPE Here again...and after getting the Pentax FA 80-320 lens at last from the vendor I ordered it from recently...and finding to my chagrin, when I mounted it on my K100D, that the manual focus of the lens is VERY "ratchety" when adjusted (the autofocus drive train does NOT seem to allow "smooth" focusing in manual focus...whether it's on the camera OR OFF of it), and that the lens' forward end seems to have a troubling, almost 1/8 inch (3 mm) wobble in it at maximum zoom...it LOOKS like I'll be sending it back to the vendor by the end of this coming week.

My film-burner K1000SE Pentax DOES have a nice, and QUITE usable, Vivitar Series 1 70-210mm f/3.5 all-manual zoom telephoto lens with it, and from Mark Roberts' site on my lens, at Vivitar 70-210 Series 1 Macro Zooms - Mark Roberts Photography , my version is the ORIGINAL version of this lens, as Mark's photo at that site shows. The leftmost lens in his five-lens-side-by-side photo certainly appears to have the straight "marking lines" on its lens barrel, JUST like mine does, and my lens has the 67mm diameter front end on it...that quite likely makes it the very first produciton version of the lens, and I'm just glad to have gotten it over a decade ago from KEH.

Now, I WOULD like to try using my Vivitar on the K100D...I'm already aware of the need to set, in the "custom" menu on my camera, the feature that allows the aperture ring to be used on such a vintage lens like my Series 1 zoom...and even though I've set it already, I'n not sure if the "FI with S lens used" setting has any meaning when using an all-manual K-type bayonet mount SLR lens.

So, I WOULD like to get good, usable hints as to just WHAT to do, when I'm trying to get photos on my K100D with the Vivitar. It seems like the "beeping red square", that usually flashes briefly with its customary two quick "beeps" when I'm in focus with a regular Pentax DA lens, is working...I do seem to be able to manually focus "wide-open", with no "stop-down darkening" in the optical viewfinder when I vary the aperture ring setting (the only method I'd ever use for viewing the focus on the K100D IS thru the optical viewfinder)...and UNlike the K10D, there is absolutely NO 'GREEN BUTTON' of any sort on the lower priced K100D to "stop-down" the aperture on the camera, so if anyone has some good tips on how to use my K100D productively with the Vivitar lens, please DO NOT mention "the green button", as my Pentax K100D does NOT have one.

Hoping to get some answers on this soon...as I'd also like to try out my Pentax 50mm f/2 prime on the K100D...

Yours Sincerely,

The PIPE!

[code4code5]

I also have the same question regarding my new K100D. I have a couple of great manual lenses that I want to use, but exposure seems to me nothing better than a guess. Is there any internal metering system for manual lenses?

Edit: I found the answer to my own question.
http://www.pentaxforums.com/forums/9174-post5.html
Sure am glad I found this place!! Thank you.

[Matthew Allen]

There is no Green button, but there is the AE-L button which performs exactly the same function in Manual mode.

Matthew

[Fritz]

Originally Posted by Matthew Allen

There is no Green button, but there is the AE-L button which performs exactly the same function in Manual mode.

Matthew

Yep, very simple. I use it all the time with very good results.

If you don't have any screw mount lenses that you are using, I wouldn't worry about changing the "FI with S lens" setting. And the red flashing square is not the focus indicator, it's the auto focus point. The green hexagon is the focus indicator.

HTH