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12-02-2011, 04:24 PM   #106
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What Adam said.

QuoteOriginally posted by neil1 Quote
doe not have ring, the lens is a da 18-250 pentax
I've tried using non-expensive TCs on my DA18-250. They suck. I get better results just by cropping the picture.

12-04-2011, 07:04 AM   #107
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QuoteOriginally posted by Marc Sabatella Quote
The only things you should need to set are the same things you would have had to set on the K20D - the "Use Aperture Ring" option in the menu, and be sure to be in M mode.
I have good success in AV mode.
12-04-2011, 03:25 PM   #108
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Sure, if you only want to shoot wide open. If you actually want to control the aperture with a manual K-mount lens, you must use M mode. Otherwise the aperture stays wide open.
12-27-2011, 06:42 PM   #109
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I came on here to ask about manual focusing with screw mount lenses, but after reading I have another question.

1) I have some Takumar lenses for indoor ice skating/gymnastics. Can I use 'catch in-focus' with these on my Kx? I've read the manual and tried, but am not having any luck. I experience alot of operator error still, so I wanted to make sure I wasn't missing something. Any other focusing tips would be appreciated as well.

2) I just read the section on metering and found it helpful, thank you. My question is about your comment at the bottom on Av setting. Generally speaking, when would I use this setting over the "M" (manual) setting? How can it help me or when could I use it to my advantage?

I'd love to have a capable zoom, but can't afford the lenses it would take to put out the kind of pictures I want to get (it's really bad lighting). The Taks are doing a really nice job....albeit without the conveniences of auto anything or any zoom (not to mention I'm a noob and barely know how to use them yet, much less get the most out of them). Thanks in advance!

12-27-2011, 07:49 PM   #110
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1) Yes, you can use CIF (catch in focus). BUT... you need to safely short the contacts on the body mount. With many M42s, that's easily done: put a bit of metal duct-repair tape (NOT cloth-plastic duck tape!) on the lens base. BUT... some Taks and other M42s have narrow bodies and won't cover the contacts. You can maybe put a bit of metal foil over the contacts, and it might work, or maybe not.

2) M(anual) mode works with any lens. But the Green button won't stop-down the lens for metering and exposure, as it will with PK lenses. Setting the camera to any Auto mode with an M42 lens, the camera defaults to Av mode. In either M or Av, you use the lens' apertures ring to control the iris opening. Which is best? I'll use Av for "just shooting", and M when reading off a gray card or otherwise setting the exposure for incident (ambient) light, not reflected light.

You maybe know some of the tricks for shooting action in low light:

* Boost the ISO -- digital noise can be fixed in PP, motion blur can't.
* Prefocus on a known location and wait for the action to reach there.
* Shoot subjects moving towards you, not moving across the visual field.
* Use wider lenses -- lower shutter speeds are usable. And don't forget SR.

Does this help?
12-27-2011, 08:18 PM - 1 Like   #111
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My Super Tak 50/1.4 has easily replaced my 18-200 as my standard lens. Hasn't come off the camera since June (except for extension tubes).
K20D makes a great combination with it. Limited (actually no) zoom range is nothing to worry about. Any prime user will make that clear.
For me, it's a bonus. Anyway, enjoy your manual lenses, everyone!
01-22-2012, 04:49 PM   #112
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Flash with M50 on K-x

I'm having real troubles using my M50 f1.7 with my K-x and the pop-up flash.
Is there any quick way of getting exposure set properly?
I'm within the parameters as defined by the equations on pg 160 of the K-x manual, but it is so hard to get a pic that is not completely blown out.
I also have an A50 f2, so I thought I would shoot with that first and copy those setting on the M50. For a good exposure using the flash with the A50, the K-x rightly calculated for a good exposure:
1/180 sec at ISO 800 using f2
That was a complete blow out on the M50, and I finally (after much trial and error) got an acceptable shot using:
1/180 sec at ISO 100 using f8 and turning down the flash by 2 steps.

SO:
  1. Is there a quick way to get proper exposure using a M lens with the popup flash?
  2. Why should there be such a difference between the settings used by the A50 and M50?
Thanks for any help.
01-22-2012, 04:58 PM   #113
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Because the A lens can communicate electrically with the camera and set the aperture to work with the flash; the M lens can't.

You need to know the flash's output is GN13 (meters, ISO100) and calculate and set the aperture yourself for correct flash exposure.

Divide the GN by the subject distance to get aperture. So a subject four meters away would be 13 divided by 4 so somewhere between f2.8 and f4 would be about right. Compensate accordingly when using different ISO settings.

The A lens can use P-TTL. The camera fires a pre-flash and can adjust flash output. With an M lens it is full blast or nothing. So when you shot with the A lens it is almost certain that the flash was firing with less than full power, which would account for why the M was blown out at the same settings....the flash output was higher, although you couldn't notice it.


Last edited by Mike Cash; 01-22-2012 at 05:04 PM.
01-22-2012, 06:02 PM   #114
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@Mike Cash: Thanks. That makes sense...
I was using the EXIF info from the A50 shot, so I had hoped that they would get me in the ballpark. The EXIF didn't indicate anything about reduction in flash power, but I suspect that might not be indicated simply because I did not adjust it.

I did a few more shots w/ the M50, and it seems that I can get close to the right exposure by simply setting it 1/180 and using the ISO calculations to get the right f-stop, but I still have to close it down another full stop (or reduce ISO) to get a better exposure.

Thanks again.
01-23-2012, 10:39 AM   #115
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The reason the Exif doesn't record the flash power output is because there is no standardized way of recording that info. Might be buried in the maker notes somewhere.

I find that even though I *can* get a good flash expsoure with an M lens through the old fashioned method of stopping down to the aperture suggested by distance to subject divided by the flash's guide number, the full power flash is really harsh looking and blinding to subjects. Not worth the effort.
02-19-2012, 05:11 PM   #116
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My K100D Super will not fire with a Sigma DL 100-300 lens..why?
02-19-2012, 05:36 PM   #117
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QuoteOriginally posted by Adam Quote
First, if your camera won't fire, set "Allow aperture setting other than A" to 2 (allowed) in the custom function menu.
Read the first post

Since that 100-300mm lens is AF, all you need to do is put the aperture ring in the "A" position and use the e-dials to control the shutter speed and aperture.

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02-22-2012, 06:08 AM   #118
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Well this has been a useful thread.
I do equestrian photography twice a week with either a film Contax with an 80/1.4 or two Leica M`s for the closer stuff.
I was considering a DSLR using the Zeiss Contax lenses but didn`t want to go down the Canon route.

From reading this thread I could also consider using my Pentax 100/2.8 or my 120/2.8 on a Pentax DSLR with the additional benifit of in body stabilisation .
I had no idea that they would still meter ...and give me focus confirmation aswell.
Looks like a no brainer .....esp as I love the two Pentax lenses.
Thanks for the info.

Michael
04-26-2012, 08:18 PM   #119
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Shouldn't the instructions in the first post be updated?

QuoteQuote:
Set your camera to M mode using the mode dial (your camera won't fire in other modes*)
It will take a picture in other modes (at least Av) but the result will be the common overexposed photo that so many talk about at first.
04-27-2012, 12:01 PM   #120
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QuoteOriginally posted by michael markey Quote
Well this has been a useful thread.
I do equestrian photography twice a week with either a film Contax with an 80/1.4 or two Leica M`s for the closer stuff.
I was considering a DSLR using the Zeiss Contax lenses but didn`t want to go down the Canon route.

From reading this thread I could also consider using my Pentax 100/2.8 or my 120/2.8 on a Pentax DSLR with the additional benifit of in body stabilisation .
I had no idea that they would still meter ...and give me focus confirmation aswell.
Looks like a no brainer .....esp as I love the two Pentax lenses.
Thanks for the info.

Michael
This is why I still shoot Pentax - in-body stabilization and easy use of legacy lenses.
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