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01-30-2014, 04:15 PM   #1
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Questions about upgrading to Legacy Lenses

Hello Pentaxians
I just bought a k-30 at the beginning of this month as my first DSLR. And I am reading like crazy. Books, reviews, articles, online lessons...Im giving my best to the craft right now. But I think Im reading too much because Im getting a little swamped.

Today, I just wanted some simplified information about the m42 mount to K mount, and the ways to get old lenses to my k-30.
I read a lot of the extensive amount of information on this wonderful community website that is ours, but honestly its sometimes hard for a noob to grasp what the technical nuances are between this or that.

So what I wanna know is:

- How hard is it to use the m42/K mount. How long (minutes,seconds...) does it take you generally to put it/take it off your camera?
- Would it be possible to just leave the mount on the lens?
Like let's say I have a SuperTakumar 50mm f/1.4, can I put the adapter on the lens, screw it to the k-30, then after Im done, take the lens (with the adapter still attached to it) and leave it on the lens, as a "fake" K-mount lens?
- How trustworthy are the 3rd party M42/K-mount adapters that we find on ebay. They say "focus to infinity fixed,...blablabla" But is it really? is it enough to trust them? Are they a valid solution? Do you own one? how is it?
- Regarding Pentax lenses, I was looking at the different 50mm f/1.7, and found 4 of them. The differences start with their name
smc Pentax M,A,F,FA... Could you please help me highlight the main differences between theses models. I would love one, but I get lost in the details of it and cant remember which does this or not, and so on.

I know its a lot of questions, and the answers to these questions are all on the website. The reason Im asking is because after reading for 3/4 days Im really lost in the technicalities of it and cant really remember what is what simply.

Please help me if you can,
if you cant its ok, I'll keep reading.

Thank you all for your time.

01-30-2014, 04:23 PM   #2
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This article explains the difference between the different lens series (M, A, FA, etc)

Pentax K-Mount Lenses Explained: The differences between various Pentax lens series

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01-30-2014, 04:29 PM   #3
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Original Poster
QuoteOriginally posted by Adam Quote
This article explains the difference between the different lens series (M, A, FA, etc)

Pentax K-Mount Lenses Explained: The differences between various Pentax lens series
thanks Adam
01-30-2014, 04:44 PM   #4
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For what it's worth , here are my $0.02

First of all, all the infinity focusing adaptors are designed to be installed by putting them on the lens, but removed by either hand or of tool, after unscrewing the lens. While you can take the retaining spring off, and attach per innately the mount to the lens, you get caught with the issue that there is no locking mechanism, and people have had lenses fall off.

Any of the flanged adaptors have a locking pin slot, but impact infinity focus, so you either live with list infinity focus, which may be ok on tele's but not WA lenses or you can readjust infinity focus, which is not always easy. Me, I have an adaptor per innately installed on my K10D, I think of it as a digital spotomatic

01-30-2014, 04:57 PM   #5
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QuoteOriginally posted by Styx1284 Quote
- How hard is it to use the m42/K mount. How long (minutes,seconds...) does it take you generally to put it/take it off your camera?
m42 lenses have a long thread, so there is a fair bit of (un)winding to mount/remove them. The genuine Pentax adapter takes seconds to remove, but you need a free hand (so swapping a m42 and k-mount lens is slightly longer than just two k-mount lenses). But practice speeds things up.
QuoteOriginally posted by Styx1284 Quote
- Would it be possible to just leave the mount on the lens?
It requires some modification, but its possible. There are threads about this, I think.
QuoteOriginally posted by Styx1284 Quote
- How trustworthy are the 3rd party M42/K-mount adapters that we find on ebay
impossible to answer, there are too many unbranded adapters with undocumented differences. Some are great, others are a nightmare. Best to order something someone already tried,
QuoteOriginally posted by Styx1284 Quote
smc Pentax M,A,F,FA
K and M are oldest. Camera can stop them down, but you need to select the aperture on the lens, by hand. You need to input focal length manually. Can only shoot in M mode and Av mode (but Av is always wide open). Stop down metering with green-button.
A lenses have auto-aperture. This means there is an A setting on the aperture ring, which lets you control the aperture from the camera body. This also unlocks Av and other modes. Continuous auto metering.
F and FA lenses are newer, they have AF and are basically fully automatic, but they still have aperture ring and such things.
DA are newest, which are the most automatic and they don't have aperture ring and often don't even have distance scales.
01-30-2014, 05:12 PM   #6
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just get an adapter that looks like the original. as long as it mounts flush in the K-mount, and the lenses screw right back flash against it, you will be fine.

Old glass is a fun way of getting your fingers across your camera. All of a sudden none of the automation works and you will be benefited from learning what everything does

If you are not patient tho...

Its a slippery ladder however. Once you have access to a M42 mount all of a sudden seemingly exotic glass dating back from the 1920's seem appealing! They will be at first. But like a junky high from his first hit, that initial feelings becomes hared to replicate.

You find yourself on ebay scrolling through pages and pages for that early pre something xyz that is made of unobtanium. You divide your time focusing on old bodies with lenses in the background you just can't read but assure yourself it has the markings and sighs of the rare one you seek. you spend the weekends visiting second hand stores looking for that last item. That last item that will complete the set. The set that never does transform you into that Pulitzer Prize winner, and that's not the point you tell yourself. It's not the point.

What was the point? Oh that's right, you cant really remember.

*looks thoughtfully at the pile of camera bodies and lenses I have collected over time*

You should buy an Industar 50
01-30-2014, 06:23 PM   #7
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My two cents worth. The adapter is easy to mount and dismount, but changing between K and M 42 mount lenses in the field would certainly slow one down. I decide whether it's going to be a K mount or a Takumar day in advance and just switch within mount types any given day or shooting session. Without too much difficulty and expense it's possible to acquire a few m 42 lenses that will cover a range of focal lengths.
01-30-2014, 06:43 PM   #8
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It takes me a good minute or so to dismount an M42 and mount up a K mount

First unscrew the lens (can be cumbersome for large lenses like the Tair3), then use fingernail to unclick the holder on the adapter (using a genuine Pentax item), then twist and remove, then screw adapter back onto lens, then cap lens with a K mount cap, then finally mount up the new K mount lens.

01-30-2014, 06:47 PM   #9
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QuoteOriginally posted by tromboads Quote
You should buy an Industar 50
I have one on the way from Moldova
01-30-2014, 07:16 PM   #10
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You signature already suggests the disease is strong within you :P
01-30-2014, 07:41 PM   #11

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QuoteOriginally posted by Lowell Goudge Quote
I have an adaptor per innately installed on my K10D, I think of it as a digital spotomatic
I have a yellow K-01 that always wears the Pentax adapter.
But unlike Lowell's K10D, I can't say what its analogue analogue would be!

Live view is great for framing an image with an M42 lens,
without having to open it up to full aperture
once you have it focused.

That should work fine with the K-30 as well.
01-30-2014, 08:05 PM   #12
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M lenses are usually pretty economical. Especially the 50's. A really good way to start with a manual lens which is what any screw mount lens will be. As a relatively new player to the game, I can tell that Manual lenses take some getting used to but can be immensely rewarding. The only issue I see with starting with a screw mount is that you have buy the adapter AND the lens. If you already have the lens......then it's really just apples or oranges......
01-30-2014, 10:45 PM   #13
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I prefer to get an adapter for every M42 lens, remove the springs from them and use the lenses as fake K-mounts. I don't try that with anything too heavy. The controls have to move easily; a tight focus ring will dismount the lens. A handful of lenses have a tapered narrow base that is smaller than the adapter. Those lenses are going to be a little wobbly on the camera and may need some work to fit better. I have one adapter that didn't work until I did a lot of filing. All mine were bought years ago so I can't recommend a current vendor.

It took me a while to adjust to the shooting style of M42, especially when I went out with an M42, M, and FA lenses at the same time. I remember being frustrated changing not only the lenses, but camera settings too.
01-30-2014, 11:51 PM   #14
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If I want to use M42, I leave my K-mount lenses at home. If I want to use K-mount, I leave my M42 lenses at home.
01-31-2014, 12:27 AM   #15
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First, save yourself a lot of headaches and use only the genuine Pentax M42 to K adapter - part number 30120. These days they are made in the Phillipines. Adorama sometimes has them - search on '30120'. Or here: Pentax Adapter B - Adapts Pentax K Bodies to Screw Mount Lenses 30120 As usual, Adorama is backordered.

Also as usual, B&H has it in stock - at almost twice the price. 30120 | B&H Photo Video

But do buy it from one or the other.

I leave my 30120 on my K-01 permanently - as I only shoot all legacy M42 Pentax Takumar glass.

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