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01-26-2013, 10:40 AM   #16
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QuoteOriginally posted by edgedemon Quote
this lens buying lark is stressful, but strangely enjoyable at the same time
That's a succinct way of putting LBA! That rush of blood to the head, "Ooh, must have that!"

01-26-2013, 11:02 AM   #17
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There are some 55/1.2 k-mount lenses that are less expensive than the Cosina you mentioned - the Porst Color Reflex - probably a Cosina make anyway for German distributor. It still costs a little higher than the FA50/1.4 and it is also manual focus only. If the nice bokeh from the f1.2 lens is what you are looking for...then go for it (the worst case, you can sell it later if you don't like it). I like mine and I won't be selling it - OTOH, I sold my FA50/1.4 long time ago. Once you get used to the manual focus lens, then it is not big deal to use it. For k-mount manual lens if you want to use it wide-open, you can still use Av mode and TAv mode (if you change program line to fast action), which is also very convenient. If you have the m42 lens, it is even better, as you can use any other aperture besides wide-open. Here is an example of the Porst 55/1.2 shot I took last year. Enjoy!!
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01-26-2013, 11:13 AM   #18
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That is a great shot, you did well to focus that in what Id imagine were testing conditions.
The Porst is a similar lens, but not quite the same, it has more aperture selections and one less blade at the back. I did see one online for around 30 quid less than the Ricoh Revuenon which in turn was 40 quid less than the Cosina, so there are choices all of which seem to hold their value
01-26-2013, 01:49 PM   #19
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QuoteOriginally posted by edgedemon Quote
for me, it is hard to get an understanding of the manual process?
One of the attractions of Pentax is the old quirky glass, but the price difference between M and A lenses is quite a jump.
I have a K30 coming in a week, Im upgrading from a K20D as I find manual focus on the K20D hard to get nailed, so focus peaking sounds like a godsend to me.
My only experience of manual is my macro lens, which I have a keeper rate of maybe 1% on - don't laugh, that is 0.9% better than a few months ago!
My understanding of the difference between A and M is that you don't have to set the aperture for A lenses, but why the jump in price just to save having to turn a ring to a value you want, or is there more?
The A position also allows multi-segment metering and P-TTL flash. With a manual aperture lens, the metering quietly switches to center-weighted by itself, and the flash fires at full power.

I had some trouble mixing types of lenses at first. These lenses need a different mindset because of the added metering steps, technical limitations, manual focusing, different controls. So if you switch from a modern lens, you have to switch your thinking too. On a single-dial camera, there's also the e-dial switch. On a two dial camera, I can set it so the shutter speed is always adjusted on the front of the camera, whether in Av mode or M. On a single dial camera, the dial is always doing something different.

QuoteQuote:
Im guessing Im asking as Im so so tempted to pull the trigger on a cosina or ricoh 55m F 1.2, but im worrying about the whole M bit and wondering whether to get a 50mm A 1.2 instead as that should give me similar bokeh.
I have also seen in the thread for the cosina a post where someone removed the aperture lever on the lens?!? I don't understand what advantage that would give, or why it needed to be done?
The Cosina should have a lot more coma. Mine has a lot, and I don't see that from the K or A 50/1.2. Two reasons to remove the aperture lever: using the lens on a Canon FF, the lever sometimes makes contact with the mirror, bad news. On a Pentax, the aperture ring can directly shift the aperture blades, so you can stop down in any camera mode. This is a third way to use the lens. The downside is tthe reason lenses don't work like that any more - focus works better wide open. When the lens is stopped down, the viewfinder gets darker, and depth of field increases. It's harder to see the point of focus.

01-26-2013, 01:57 PM   #20
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QuoteOriginally posted by baro-nite Quote
That's a succinct way of putting LBA! That rush of blood to the head, "Ooh, must have that!"
+1 I thought the same thing
01-26-2013, 02:37 PM   #21
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QuoteOriginally posted by edgedemon Quote
for me, it is hard to get an understanding of the manual process?
One of the attractions of Pentax is the old quirky glass, but the price difference between M and A lenses is quite a jump.
A good exposure meter would help. But this way is free.

Try walking around with an auto lens. Get yourself into a variety of lighting. Take notes, mental best or on paper of what they camera picked under the various conditions. Alternate scenario is to guess what the camera will pick and compare that to what it does pick. An old k-1000 with its match stick would teach you a lot faster

IMO, If shooting RAW, it is easier to recover an under-exposed image than one that is over.

For the average casual shooter it isn't rocket science and maybe 10 different settings are all you need to really learn. Heck the really old pre SLR cameras only had 3-4 settings.

Over time you will be able to see the light (pun intended).
01-26-2013, 03:17 PM   #22
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QuoteOriginally posted by edgedemon Quote
Thanks Adam
Does removing the aperture lever make the process any easier?
https://www.pentaxforums.com/forums/lens-clubs/41357-cosina-55mm-1-1-2-club-7.html#post436139
No, removing the aperture lever does not make the process easier.

You want the aperture open for composition and focus and stopped down for exposure and metering. The camera makes this easy for you. Work in M mode and use green-button (stop-down) metering. The metering step only takes a split second and the lens is back open again.


Steve


BTW...mangling your Cosina will decrease its market value substantially.
01-26-2013, 03:31 PM   #23
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QuoteOriginally posted by edgedemon Quote
When you say AV mode, do you mean that by removing the lever, the Camera is able to read the Apperture setting as if it was a 'A' lens?
<Also, I did open the Cosina today to perform the auto aperture lever removal and noted the internals on the back side are updated and cleaner than the Porst, but definately the same design. I didn't go further than the helical for now. For those interested, its dead easy.

1) Unscrew the back 4 screws, lift K-mount off.
2) Remove black ring attached with spring (take the spring out too).
3) Replace the K-mount.

Removing the lever ring has no effect on the tension of the aperture ring.

K. >

It can't be that easy surely?
Don't do it.

The key to using vintage glass without A contacts is in being familiar with your camera and following the instructions given elsewhere on this site along with your camera manual:
  • Shoot in M mode. Do this even with fully manual aperture lenses (no stop-down lever or pin). This allows for accurate metering with your K30. Av mode will lead to gross exposure errors.
  • Focus and compose wide open
  • If the lens supports it, let the camera stop the lens down when needed for exposure and metering.
  • Meter using the green button or hand-held meter or some other method. If using other than the green button, you will have to manually set both shutter speed and aperture.
Again...This is not rocket science, though it does require that you become familiar with the basics of exposure and how your camera and lenses of various vintage work together to make photographs.

As with medical science, surgery is always the last resort.


Steve


...unless, of course, one is a surgeon...

01-26-2013, 03:33 PM   #24
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QuoteOriginally posted by stevebrot Quote
No, removing the aperture lever does not make the process easier.

You want the aperture open for composition and focus and stopped down for exposure and metering. The camera makes this easy for you. Work in M mode and use green-button (stop-down) metering. The metering step only takes a split second and the lens is back open again.


Steve


BTW...mangling your Cosina will decrease its market value substantially.

+1 to all the above ^^
Using m-lenses with the green button is already an easy process. If you're really unsure about the whole m-lens/manual-focus thing, why not test the waters with something like an M50/1.7? At about $45 it won't break the bank, and delivers stunningly-sharp images, great color & contrast and nice bokeh wide-open. (I wouldn't butcher that 55/1.2 either!)
01-26-2013, 03:41 PM   #25
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QuoteOriginally posted by edgedemon Quote
My only experience of manual is my macro lens
According to your signature, your macro is a full-featured AF lens (has both A contacts and AF).

I would suggest that before you venture into the world of ultra-fast f/1.2 glass, that you get yourself a quality fast 50 with a more moderate aperture and use it to learn how to use your camera in manual mode. I would suggest the Pentax-M 50/1.7. It is cheap, has few negative characteristics, and is excellent in most senses of the word. It also has a fast enough maximum aperture to challenge your manual focus skills and allow you to explore the world of selective DOF.

Take your time and learn how to use the camera. Manual technique with your digital SLR is basically no different than how it was done with film cameras over the last 40 years or so.


Steve
01-26-2013, 04:21 PM   #26
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QuoteOriginally posted by Medium FormatPro Quote
About how much would it cost to adapt/convert a lens? I'm guessing it would also depend on the type of lens and all, but would there be a ballpark figure with two possible examples. Also, is there a company or person that does this that you could provide a shameless plug for?
I come from a Contax system and I love the Carl Zeiss glass. Try Leitax for conversions of CZ, leica and Olympus. David Lladó can help you, all though I have done the conversion my self. It is very easy made it while cooking pasta.
01-26-2013, 04:30 PM   #27
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I shoot manual almost exclusively - not due to any real preference but rather because thats what my lenses are.

You get used to it soon enough, and I actually like the fact that stopping down forces you to pause and consider composition and such a bit more than my AF lenses do.
01-27-2013, 09:09 AM   #28
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QuoteOriginally posted by Adam Quote
The jump in value is there because with A lenses, you can use M mode without using stop-down metering, which saves you a lot of time. The aperture value is also recorded in the EXIF info, which is nice.

If Pentax DSLR mounts weren't crippled (i.e. if they had the lever that could sense the position of the aperture ring), then M lenses would be a true joy to use and there would be little benefit to having an A lens (beyond the possibility of shooting in P mode). However, as things are right now I personally avoid M lenses simply because they're a bit of an inconvenience in the field.

Now, a non-crippled full-frame would solve both the metering issue and the focusing issue...
Wait, I am able to use M mode without stop-down metering with my M lens (50mm f/1.7). The aperture stays wide open until I press the shutter, in which case it will close down to the selected aperture on the ring. The aperture also closes down when I press the green button to get shutter speed.
01-27-2013, 09:15 AM   #29
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QuoteOriginally posted by NitroDC Quote
Wait, I am able to use M mode without stop-down metering with my M lens (50mm f/1.7). The aperture stays wide open until I press the shutter, in which case it will close down to the selected aperture on the ring. The aperture also closes down when I press the green button to get shutter speed.
When you press the green button with an M-lens, you *are* using stop-down metering .
01-27-2013, 09:17 AM   #30
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QuoteOriginally posted by paulh Quote
When you press the green button with an M-lens, you *are* using stop-down metering .
Ah, so that doesn't mean that the viewfinder is always affected by the aperture setting? Only when pressing the green button/shutter?
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