Using Manual Lenses (M42 Screwmount, M , K) on Pentax DSLRs F--

Ira · 12-26-2010, 09:26 AM

Originally posted by valarie

Hi Adam,
I have a huge amount of k,m, A and smc lenses. What dslr will get the moast out of them.

Are you asking this to help in making a DSLR purchase decision?

The benefits of using your manual glass would be equal across all models.

**valarie** · 12-26-2010, 03:12 PM

Hi Adam,
Even though I love the look of my digitized slides from my LX, i desperetly need a DSLR. I love the K-5 but it is almoast there! Pentax is ready to rejoin the pro market with a DLX. It would be a K-5 with FF, compleatly manual exposure, 1080p video with the choice of 24,25,30,60fps, focus assist for manual lenses, apature priority mode, and the ability to meter any way you want with manual lenses. Should I wait?
Thanks,
Valarie

**valarie** · 12-26-2010, 03:14 PM

Thank You

**valarie** · 12-26-2010, 03:17 PM

Thanks Ira!

RonnieG · 12-28-2010, 06:52 AM

Hi, I've got a K7 and using a 50mm pentax-m 1:2. How do I use it with the flash on? I can't adjust the speed of the flash past 1/180 hence the photos are all white.

Ira · 01-01-2011, 09:51 AM

Originally posted by RonnieG

Hi, I've got a K7 and using a 50mm pentax-m 1:2. How do I use it with the flash on? I can't adjust the speed of the flash past 1/180 hence the photos are all white.

You can never go faster than 180 with your flash. Otherwise, you would get half a picture. It's called your flash sync speed (different cameras have different speeds). You can go SLOWER than 180, but never faster. The camera won't let you.

Your pictures are all white because your ISO is set too high, or your aperture is too wide open.

Alizarine · 01-06-2011, 04:20 AM

Wow thanks for that tip! It was really helpful. Cut down the time taken to shoot... fantastic.

Green button for the win!

pentup · 01-14-2011, 04:55 PM

Does anyone know why it is that I don't have to use the green button when using a Nikkor AI-S lens on my K-7? (no adapter required; it twists on) I just put the camera in Aperture Priority mode, and set the aperture. Exposures are very accurate. However, if I set to M mode, then I have to use the green button (and it seems to give me different readings, underexposing)

Why do the Pentax lenses described here act differently?

saatiish · 01-23-2011, 09:29 PM

Getting low shutter speeds and unable to control flash - when using Pentax-M 50mm 1.7 with K-x

I recently purchased a Pentax-M 50mm 1.7 lens - to use with my Pentax k-x.

Settings on the camera -
** custom setting - Using aperture ring - Permitted.
** focal length on startup 50mm.
** Green button - action in M mode - Tv Shift.
** SR - on

For indoor shots in M mode with aperture ring dial at 1.7 (wide open) - at moderate lighting (tube lights) - pressing green button gives me a shutter speed of 1/5 to 1/15 max - which is significantly lower to be able to snap non-blur pictures of my toddler !

The ISO is typically set at 400.

Another issue - in-built Flash (at any compensation level) white washes my pictures.
I am at my wits end - I thought these are faster lens - and would be a decent upgrade to my kit lens. I can use tripods - but that can only do so much.

The apertures seem to open and shut properly with its widest at 1.7. Now - is there anthing else I should be doing ? Did I get some faulty lens ? Or is this normal and just not enough for the challenge I am putting those to ? I do not like flashes - but even that seems to not work with this lens ! My kit lens right now appears to be more useful and faster - even with its smaller apertures.

Balog · 01-26-2011, 09:01 AM

Originally posted by Adam

Compose and focus your image.
Using the aperture ring (the ring at the very back of your camera; it will have numbers such as 2.8, 4, 5.6, 8 written on it), select your desired aperture setting. Note that the smaller the aperture number is, the more light passes through the lens, and the blurrier the out of focus areas of your photograph will be.
[screwmount only] Switch the diaphragm clutch on your lens to "Manual" (you can leave it on Auto when composing and focusing).
Measure the light by either pressing the "Green Button", or pushing your power button to DOF preview mode (only available on select bodies). Your camera will automatically set the shutter speed for you.

I recently acquired my first M42 lens, and I'm wondering about #3...

Is there a reason to have the diaphragm clutch on "Auto" during steps 1 and 2, or can I leave it set to "Manual" all the time? Thank.

**crewl1** · 01-27-2011, 01:32 PM

@saatiish:
Don't be afraid to try higher iso values than you have used before with the k-x.
It still gives wonderful results at higher iso and will allow you to use faster shutter speeds without the flash.

Internal flash with manual lenses on my k-x is all trial and error. Usually have to close down the aperture, drop the iso and chimp.

Your 50/1.7 should let you skip the flash if you use the high iso capabilities of the k-x.

**boriscleto** · 01-27-2011, 02:29 PM

Originally posted by Balog

[/LIST]I recently acquired my first M42 lens, and I'm wondering about #3...

Is there a reason to have the diaphragm clutch on "Auto" during steps 1 and 2, or can I leave it set to "Manual" all the time? Thank.

If you set it to Auto it will be wide open all the time. A K-mount camera does not have a mechanism to press the aperture pin on a M42 lens, so Auto is useless. When a M42 lens is set to Manual the aperture opens and closes when you turn the aperture ring.

calicojack · 02-13-2011, 05:50 AM

Originally posted by Balog

[/LIST]I recently acquired my first M42 lens, and I'm wondering about #3...

Is there a reason to have the diaphragm clutch on "Auto" during steps 1 and 2, or can I leave it set to "Manual" all the time? Thank.

You CAN leave it on manual all the time BUT if you're using smaller apertures the viewfinder will be dark while composing and focusing. You want the lens aperture as big as possible for maximum light (Auto) then closed down to the shooting aperture (manual) for picture taking only.

tenerifepentax · 02-24-2011, 08:53 AM

so when i enter the focal lenght of the lens say my M 50mm f1.7 should it be 50mm or 75mm add the 1.5 for senor size and when its a zoom lens do you enter the smaller or bigger lenght

**crewl1** · 02-24-2011, 11:51 AM

Enter the actual focal length of the lens (50.)
This entry is used for the SR system to calculate how much shake compensation to use.

For zooms I enter the value for FL I expect to use the most, but not sure if there is any rule for that.

12-26-2010, 03:12 PM	#17
valarie Site Supporter Join Date: Dec 2010 Location: Chevy Chase, MD Posts: 69	perfectDSLR Hi Adam, Even though I love the look of my digitized slides from my LX, i desperetly need a DSLR. I love the K-5 but it is almoast there! Pentax is ready to rejoin the pro market with a DLX. It would be a K-5 with FF, compleatly manual exposure, 1080p video with the choice of 24,25,30,60fps, focus assist for manual lenses, apature priority mode, and the ability to meter any way you want with manual lenses. Should I wait? Thanks, Valarie

01-23-2011, 09:29 PM	#24
saatiish New Member Join Date: Jan 2011 Posts: 4	Getting low shutter speeds and unable to control flash - when using Pentax-M 50mm 1.7 with K-x I recently purchased a Pentax-M 50mm 1.7 lens - to use with my Pentax k-x. Settings on the camera - custom setting - Using aperture ring - Permitted. focal length on startup 50mm. Green button - action in M mode - Tv Shift. SR - on For indoor shots in M mode with aperture ring dial at 1.7 (wide open) - at moderate lighting (tube lights) - pressing green button gives me a shutter speed of 1/5 to 1/15 max - which is significantly lower to be able to snap non-blur pictures of my toddler ! The ISO is typically set at 400. Another issue - in-built Flash (at any compensation level) white washes my pictures. I am at my wits end - I thought these are faster lens - and would be a decent upgrade to my kit lens. I can use tripods - but that can only do so much. The apertures seem to open and shut properly with its widest at 1.7. Now - is there anthing else I should be doing ? Did I get some faulty lens ? Or is this normal and just not enough for the challenge I am putting those to ? I do not like flashes - but even that seems to not work with this lens ! My kit lens right now appears to be more useful and faster - even with its smaller apertures. Last edited by saatiish; 01-24-2011 at 11:29 AM. Reason: more information

01-26-2011, 09:01 AM	#25
Balog Senior Member Join Date: Jun 2010 Location: Bothell, WA Posts: 103	Originally posted by Adam Compose and focus your image. Using the aperture ring (the ring at the very back of your camera; it will have numbers such as 2.8, 4, 5.6, 8 written on it), select your desired aperture setting. Note that the smaller the aperture number is, the more light passes through the lens, and the blurrier the out of focus areas of your photograph will be. [screwmount only] Switch the diaphragm clutch on your lens to "Manual" (you can leave it on Auto when composing and focusing). Measure the light by either pressing the "Green Button", or pushing your power button to DOF preview mode (only available on select bodies). Your camera will automatically set the shutter speed for you. I recently acquired my first M42 lens, and I'm wondering about #3... Is there a reason to have the diaphragm clutch on "Auto" during steps 1 and 2, or can I leave it set to "Manual" all the time? Thank.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
How to use/meter Manual & M42 Lenses on all Pentax DSLRs (K-1, K-3, K-5, K-30, etc)	Adam	Pentax Lens Articles	357	04-16-2023 08:01 AM
Manual Metering on Pentax DSLRs with Manual and Automatic Lenses	Adam	Pentax DSLR and Camera Articles	20	01-06-2016 03:38 AM
Shooting manual lenses on Pentax DSLRs F--	Robert S Donovan	Pentax Lens Articles	2	03-25-2013 05:58 PM
Shooting manual lenses on Pentax DSLRs F--	Robert S Donovan	Troubleshooting and Beginner Help	80	01-07-2011 09:10 AM
Can I use M42 screwmount lenses on my Pentax K-mount (D)SLR?	Adam	Pentax Lens Articles	37	09-21-2009 12:56 AM

12-26-2010, 09:26 AM	#16
Ira Inactive Account Join Date: Mar 2009 Location: Coral Springs, FL Photos: Gallery \| Albums Posts: 5,216	Originally posted by valarie Hi Adam, I have a huge amount of k,m, A and smc lenses. What dslr will get the moast out of them. Are you asking this to help in making a DSLR purchase decision? The benefits of using your manual glass would be equal across all models.

12-26-2010, 03:14 PM	#18
valarie Site Supporter Join Date: Dec 2010 Location: Chevy Chase, MD Posts: 69	Thank You

12-26-2010, 03:17 PM	#19
valarie Site Supporter Join Date: Dec 2010 Location: Chevy Chase, MD Posts: 69	Thanks Ira!

12-28-2010, 06:52 AM	#20
RonnieG Junior Member Join Date: Sep 2009 Location: Melbourne Posts: 25	Hi, I've got a K7 and using a 50mm pentax-m 1:2. How do I use it with the flash on? I can't adjust the speed of the flash past 1/180 hence the photos are all white.

01-01-2011, 09:51 AM	#21
Ira Inactive Account Join Date: Mar 2009 Location: Coral Springs, FL Photos: Gallery \| Albums Posts: 5,216	Originally posted by RonnieG Hi, I've got a K7 and using a 50mm pentax-m 1:2. How do I use it with the flash on? I can't adjust the speed of the flash past 1/180 hence the photos are all white. You can never go faster than 180 with your flash. Otherwise, you would get half a picture. It's called your flash sync speed (different cameras have different speeds). You can go SLOWER than 180, but never faster. The camera won't let you. Your pictures are all white because your ISO is set too high, or your aperture is too wide open.

01-06-2011, 04:20 AM	#22
Alizarine Veteran Member Join Date: Dec 2010 Location: Manila Photos: Gallery \| Albums Posts: 2,185	Wow thanks for that tip! It was really helpful. Cut down the time taken to shoot... fantastic. Green button for the win!

01-14-2011, 04:55 PM	#23
pentup Veteran Member Join Date: Jul 2010 Location: Flushing NY Photos: Albums Posts: 413	Does anyone know why it is that I don't have to use the green button when using a Nikkor AI-S lens on my K-7? (no adapter required; it twists on) I just put the camera in Aperture Priority mode, and set the aperture. Exposures are very accurate. However, if I set to M mode, then I have to use the green button (and it seems to give me different readings, underexposing) Why do the Pentax lenses described here act differently?

01-27-2011, 01:32 PM	#26
crewl1 Site Supporter Join Date: Jul 2010 Location: Los Angeles, CA Photos: Gallery \| Albums Posts: 9,807	@saatiish: Don't be afraid to try higher iso values than you have used before with the k-x. It still gives wonderful results at higher iso and will allow you to use faster shutter speeds without the flash. Internal flash with manual lenses on my k-x is all trial and error. Usually have to close down the aperture, drop the iso and chimp. Your 50/1.7 should let you skip the flash if you use the high iso capabilities of the k-x.

01-27-2011, 02:29 PM	#27
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,284	Originally posted by Balog [/LIST]I recently acquired my first M42 lens, and I'm wondering about #3... Is there a reason to have the diaphragm clutch on "Auto" during steps 1 and 2, or can I leave it set to "Manual" all the time? Thank. If you set it to Auto it will be wide open all the time. A K-mount camera does not have a mechanism to press the aperture pin on a M42 lens, so Auto is useless. When a M42 lens is set to Manual the aperture opens and closes when you turn the aperture ring.

02-13-2011, 05:50 AM	#28
calicojack Inactive Account Join Date: Mar 2007 Location: Long Island, N.Y. Photos: Gallery Posts: 1,124	Originally posted by Balog [/LIST]I recently acquired my first M42 lens, and I'm wondering about #3... Is there a reason to have the diaphragm clutch on "Auto" during steps 1 and 2, or can I leave it set to "Manual" all the time? Thank. You CAN leave it on manual all the time BUT if you're using smaller apertures the viewfinder will be dark while composing and focusing. You want the lens aperture as big as possible for maximum light (Auto) then closed down to the shooting aperture (manual) for picture taking only.

Thread Tools	Search this Thread
	Search this Thread: Advanced Search

02-24-2011, 08:53 AM	#29
tenerifepentax Inactive Account Join Date: Feb 2011 Posts: 4	so when i enter the focal lenght of the lens say my M 50mm f1.7 should it be 50mm or 75mm add the 1.5 for senor size and when its a zoom lens do you enter the smaller or bigger lenght

02-24-2011, 11:51 AM	#30
crewl1 Site Supporter Join Date: Jul 2010 Location: Los Angeles, CA Photos: Gallery \| Albums Posts: 9,807	Enter the actual focal length of the lens (50.) This entry is used for the SR system to calculate how much shake compensation to use. For zooms I enter the value for FL I expect to use the most, but not sure if there is any rule for that.