New to M42 mount lens

okitoki · 12-23-2008, 06:38 PM

Hi all,
well, yesterday was Christmas morning for me, as I have received my lovely 50mm and 35mm primes from a fellow member... after much waiting for the long working day to finish... I rushed home and tested the lenses on my K200D...

As I never used the M42 adaptor, I wasnt sure what to expect... but when I screwed the lens on, it became tight before it the position I thought it should be aligned... (Maybe a photo would be good here :P)... or to put it another way, I am not sure if I screwed the lens in far enough...

would this affect the quality of the pic? or since it is a manual lens, would it really matter?

Also, noticed some of the lens contact on the body is also exposed... I assume this is normal, and usual precaution is needed about avoiding liquid and dust?

sorry for the noobish questions

*RobA_Oz* · 12-23-2008, 07:21 PM

No question's worth apologising for, Joseph.

I suspect you may have a similar adapter to one of mine (cheap and poor copy of the Pentax original). See my post here: macro extension tube on ebay

There are some good new adapters available, and second-hand ones come up from time to time. The original Pentax ones are well-made, as you'd expect, and easy to use. There are some posts here, which you can find on search, but which I don't have to hand, sorry, on making adapters semi-permanent fixtures to the M42 lenses.

Rob

*newarts* · 12-23-2008, 09:13 PM

I am not sure if I screwed the lens in far enough...

would this affect the quality of the pic? or since it is a manual lens, would it really matter?

It must be screwed in until the m42's base touches the camera's flange surface or you can't focus at infinity. Other than that there's no problem.

The adapter you are using should have no broad flange interfering with the m42's base touching the camera's flange or it will prevent infinity focus.

You may want to use aluminum foil to short out the electrical contact pins on the camera's flange; that will help you get the proper exposure measurements and allow for "focus trapping" mode (set record mode to AF.S - then the shutter won't trigger until focus is achieved.)

Or you can sand some of the paint off the base of the m42's base so it will make electrical contact.

Here's the link to the thread Rob probably referred to:
Screw to K mount adapters

Stratman · 12-23-2008, 09:56 PM

Even with the genuine Pentax adapter, the lens will not tighten to "the middle" the red mark for the aperture will be a little off to the side, it is perfectly normal. Nothing to worry about. Here is my K10 with the genuine adapter and my 55 1.8 mounted..

eccs19 · 12-24-2008, 05:59 AM

Originally Posted by Stratman

Even with the genuine Pentax adapter, the lens will not tighten to "the middle" the red mark for the aperture will be a little off to the side, it is perfectly normal. Nothing to worry about. Here is my K10 with the genuine adapter and my 55 1.8 mounted..

Hmm, that's funny. I've also got a genuine adaptor, and mine comes a lot closer to the top than your does. Not perfect, but a lot closer than yours. Maybe I'm just tightening it too much.

*séamuis* · 12-24-2008, 06:32 AM

Originally Posted by eccs19

Hmm, that's funny. I've also got a genuine adaptor, and mine comes a lot closer to the top than your does. Not perfect, but a lot closer than yours. Maybe I'm just tightening it too much.

mine also comes a lot closer.

Mike Cash · 12-24-2008, 06:44 AM

Originally Posted by newarts

Or you can sand some of the paint off the base of the m42's base so it will make electrical contact.

Where do you guys keep getting lenses that are fat enough to cover the contacts at all? None of my Takumars with 49mm filter threads do that.

*newarts* · 12-24-2008, 07:56 AM

Originally Posted by Mike Cash

Where do you guys keep getting lenses that are fat enough to cover the contacts at all? None of my Takumars with 49mm filter threads do that.

Mike, Here's a 50mm Macro Takumar (49mm filter) mounted; There is sufficient contact (but it doesn't look like there is!) I was surprised that so little overlap is needed.

Dave

okitoki · 12-25-2008, 04:20 AM

cool..

thanks for the quick feed backs on the fitting... I have tested a few shots of the 50 and 35mm today; and seems to worked well..

Stratman · 12-25-2008, 11:27 AM

Originally Posted by eccs19

Hmm, that's funny. I've also got a genuine adaptor, and mine comes a lot closer to the top than your does. Not perfect, but a lot closer than yours. Maybe I'm just tightening it too much.

I just "snug" my Taks up, I don't try to crank them as tight as I can. I did notice on my one S-M-C Tak, the 200mm F4, that it gets a lot closer to being "centered" than my Super Taks do..

*séamuis* · 12-25-2008, 12:47 PM

Originally Posted by Stratman

I just "snug" my Taks up, I don't try to crank them as tight as I can. I did notice on my one S-M-C Tak, the 200mm F4, that it gets a lot closer to being "centered" than my Super Taks do..

I wonder if its because of a difference in the threads on the adapters old vs. new or if its a difference in the threads between the different takumar series? or maybe both?

Stratman · 12-25-2008, 01:30 PM

Originally Posted by séamuis

I wonder if its because of a difference in the threads on the adapters old vs. new or if its a difference in the threads between the different takumar series? or maybe both?

I have no idea, lol, whatever it is, I sure like how the images look with the Takumars

*Andi Lo* · 12-25-2008, 01:43 PM

Why would one put a filter in between the lens and body? just curious =) Will it act as both a protector and an extension tube?

*séamuis* · 12-25-2008, 01:51 PM

Originally Posted by Andi Lo

Why would one put a filter in between the lens and body? just curious =) Will it act as both a protector and an extension tube?

where did you see that?

*Andi Lo* · 12-25-2008, 04:52 PM

Newarts poted an image of his 50mm macro that *looks* like it has a filter at the base of the lens and said that it has a 49mm filter. Maybe I have misinterpreted his sentence, though.