Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version 2 Likes Search this Thread
12-10-2008, 01:34 PM   #106
Veteran Member
Miserere's Avatar

Join Date: Sep 2007
Location: Boston
Photos: Gallery
Posts: 1,993
QuoteOriginally posted by Class A Quote
You can use Av, even when not shooting wide open. Just dial in the appropriate exposure compensation.
That would be nice, but it doesn't work. When shooting a non-A lens in Av the camera will not stop the lens down when it takes a shot; it always shoots the lens wide open, independently of what you have set on the aperture ring.

12-10-2008, 01:38 PM   #107
Veteran Member
Gooshin's Avatar

Join Date: Sep 2007
Location: Toronto, the one in Canada.
Posts: 5,610
thats why you can perform a simple operation and remove the aperture pin!

the downside of which is a dark viewfinder at F5.6 and above, but ohh well.
12-10-2008, 02:43 PM   #108
Veteran Member
Miserere's Avatar

Join Date: Sep 2007
Location: Boston
Photos: Gallery
Posts: 1,993
QuoteOriginally posted by Gooshin Quote
thats why you can perform a simple operation and remove the aperture pin!

the downside of which is a dark viewfinder at F5.6 and above, but ohh well.
Tell me again why you're using this lens at f/5.6...?

Maybe I'll non-destructively remove the aperture lever from the lens and give it a test run to see how it handles. I've not had issues using M42 lenses, and in some ways I prefer them to M lenses.
12-10-2008, 04:02 PM   #109
Pentaxian
Class A's Avatar

Join Date: Aug 2008
Location: Wellington, New Zealand
Posts: 11,251
QuoteOriginally posted by Miserere Quote
When shooting a non-A lens in Av the camera will not stop the lens down when it takes a shot; it always shoots the lens wide open,
Depends on the lens, doesn't it? I believe it works with Takumar preset lenses where you can set the aperture manually without the camera keeping it open. I agree that this isn't terribly relevant for this particular thread.

12-10-2008, 05:52 PM   #110
Inactive Account




Join Date: Sep 2007
Location: Calgary, AB
Photos: Gallery
Posts: 942
QuoteOriginally posted by Gooshin Quote
thats why you can perform a simple operation and remove the aperture pin!

the downside of which is a dark viewfinder at F5.6 and above, but ohh well.
Agreed.

1) Remove the screws holding the bayonet mount on, lift away.

2) Underneath you'll see a stack of two metal rings, one of which is attached to the aperture lever, remove this ring.

3) Replace the bayonet housing.

It can add a tiny extra bit of play in the aperture ring on the Porst, but now you have a fully manual lens. The ring can be replaced if you wish to reverse the procedure.

Regarding Av mode, I find I use it a lot with manual lenses such as this, but always M mode for my 'A' lenses. I've learned to enjoy shooting both ways, as long as I have full control of the lens.

K.
12-10-2008, 08:21 PM   #111
Veteran Member
Miserere's Avatar

Join Date: Sep 2007
Location: Boston
Photos: Gallery
Posts: 1,993
Huh?

Wait, Kelly, so you're saying that you shoot your modified M lenses in Av, but your A lenses in manual...?

12-10-2008, 09:36 PM   #112
Veteran Member
jgredline's Avatar

Join Date: Oct 2007
Location: LosAngeles, Ca.
Photos: Albums
Posts: 10,628
Is it not easier to simply put the camera in Manual mode and use the green button. Choose tha aperture you want and let the camera choose the shutter speed and fine tune from their? Works for me.

12-11-2008, 06:09 AM   #113
Veteran Member
Gooshin's Avatar

Join Date: Sep 2007
Location: Toronto, the one in Canada.
Posts: 5,610
QuoteOriginally posted by jgredline Quote
Is it not easier to simply put the camera in Manual mode and use the green button. Choose tha aperture you want and let the camera choose the shutter speed and fine tune from their? Works for me.
the green button method doesnt adjust on the fly, its just an extra step thats in the way of photo taking, plus AFAIK its spot metering only.

keeing the lens in Av you adjust on the fly, and you have your choice of metering modes.
12-11-2008, 04:03 PM   #114
Veteran Member
KjetilH's Avatar

Join Date: Mar 2008
Location: Oslo
Photos: Gallery
Posts: 309
As far as I know, the green button follows the metering mode, center-weighted or spot, selected. Works fine with center-weighted (which anyway is my default), but a better challenge is picking readings off surfaces you consider suitable (e.g. grass or concrete). Quite fun, at least when shooting randomly.
12-11-2008, 07:38 PM   #115
Inactive Account




Join Date: Sep 2007
Location: Calgary, AB
Photos: Gallery
Posts: 942
QuoteOriginally posted by Miserere Quote
Wait, Kelly, so you're saying that you shoot your modified M lenses in Av, but your A lenses in manual...?

Yes. When the camera is accurately compensating the meter for aperture changes (A lenses), I've come to rely on my ability interpret what the meter is telling me in a given circumstance to get the exposure I want. This is my preferred method of working.

With the modded Porst and other M42 lenses, the meter isn't giving out the same feedback to work with. The green button can give a snap shot of a specific instance of subject, but if I'm shooting dynamically, Av mode is like a constantly updated version of hitting the green button, so I let the camera decide the base shutter speed and adjust the EV either predictively based on experience, or on the fly. I regard this method of chasing ideal exposure a little less confidantly, but as my predictive sense of what the camera is doing grow, my results are improving.
11-12-2011, 11:26 AM   #116
Senior Member




Join Date: Sep 2010
Location: Zhukovsky,Russia / SF Bay Area
Posts: 249
The thread is old, but I think it worths this picture. I was lucky to collect and compare few f1.2 lens including 3 different kinds of Cosina clones. Optically all Cosina's have no difference. Cosina and Revue -- no exterior difference, just a name one. Vivitar -- slightly different as you can see. Vivitar is quite rare, maybe limited production in 74-75.



I also have Pentax 50/1.2. Pentax lens is slightly sharper, but it is sometimes too 'right'.

I also had Porst 55/1.2 before, and while Porst is slightly softer, there are two notable pros:
- minimum focusing distance is about 40-45cm (Cosina -- 60)
- the construction is more solid, and it feels more reliable.
11-12-2011, 11:50 AM   #117
Veteran Member
blende8's Avatar

Join Date: Feb 2007
Location: Bremen, Germany
Photos: Albums
Posts: 1,521
QuoteOriginally posted by kaipa Quote
- the construction is more solid, and it feels more reliable.
This may feel so, but is not true.
I already saw several Porsts that had problems with the focussing ring, including mine. After some time it didn't move at all anymore.

I now have the Revuenon, which is excellent.
11-12-2011, 02:47 PM   #118
Senior Member




Join Date: Sep 2010
Location: Zhukovsky,Russia / SF Bay Area
Posts: 249
QuoteOriginally posted by blende8 Quote
This may feel so, but is not true.
I already saw several Porsts that had problems with the focussing ring, including mine. After some time it didn't move at all anymore.
Maybe internals are not so good. But it 'feels' solid. It's genuine lens cap is much better than Cosina's. And it is much easier to mount/dismount than Cosina/Revue.

Btw, have you fixed the focusing? It should not be difficult to disassemble. I am considering to buy one more Porst that has exactly this problem for the cheap price. But not sure if it is easy to fix or not.
11-12-2011, 11:03 PM   #119
Banned




Join Date: Nov 2009
Location: WA
Photos: Albums
Posts: 3,055
QuoteOriginally posted by kaipa Quote
The thread is old, but I think it worths this picture. I was lucky to collect and compare few f1.2 lens including 3 different kinds of Cosina clones. Optically all Cosina's have no difference. Cosina and Revue -- no exterior difference, just a name one. Vivitar -- slightly different as you can see. Vivitar is quite rare, maybe limited production in 74-75.
Wow! Nice collection. I didn't even know that a Vivitar Series 1 version of the 55/1.2 existed. I am wondering why they stopped production of this lens - does anyone know what was its cost when it was released? Would it cost too much to make today? I hope Samyang will make a 50mm faster than 1.4 some day.
11-13-2011, 01:57 AM   #120
Veteran Member
blende8's Avatar

Join Date: Feb 2007
Location: Bremen, Germany
Photos: Albums
Posts: 1,521
QuoteOriginally posted by kaipa Quote
Btw, have you fixed the focusing? It should not be difficult to disassemble. I am considering to buy one more Porst that has exactly this problem for the cheap price. But not sure if it is easy to fix or not.
No, I didn't try that.
The two I have seen myself felt the same, as if sand was in there, a very bad creaking, grating sound. Probably something was broken.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
bud, cosina 55mm f1.2, crop, focus, fun, iso, k-mount, lens, pentax lens, shots, slr lens, test, time

Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: Cosina 55mm 1:1.2 DaddyLuna Sold Items 5 06-18-2009 05:22 PM
First shots with Cosina 55mm f/1.2 mikeSF Post Your Photos! 15 03-27-2009 08:58 PM
Cosina 55mm f1.2 kibipod Pentax SLR Lens Discussion 2 12-13-2008 08:26 AM



All times are GMT -7. The time now is 05:35 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top