Oldish lens?

Moonraker · 08-16-2015, 01:01 AM

Morning everybody,
I bought second hand a Pentax 28mm lens, , the markings are smc PENTAX-A 1:2.8 28mm, serial No 5138600.
Can anyone out there give me any info on this lens please?
John

**Kerrowdown** · 08-16-2015, 01:13 AM

Originally posted by Moonraker

Can anyone out there give me any info on this lens please

I would think it's going to be one of these two and probably the first as you mention A in the name, info right here on the forum.

I hope this helps.

SMC Pentax-A 28mm F2.8 Reviews - A Prime Lenses - Pentax Lens Reviews & Lens Database
SMC Pentax-M 28mm F2.8 Reviews - M Prime Lenses - Pentax Lens Reviews & Lens Database

Moonraker · 08-16-2015, 01:40 AM

Originally posted by Kerrowdown

I would think it's going to be one of these two and probably the first as you mention A in the name, info right here on the forum.

I hope this helps.

SMC Pentax-A 28mm F2.8 Reviews - A Prime Lenses - Pentax Lens Reviews & Lens Database
SMC Pentax-M 28mm F2.8 Reviews - M Prime Lenses - Pentax Lens Reviews & Lens Database

Thanks for that, it is certainly an A, I will have to find out to use it on my K3, at the moment the camera wont fire with it on, I have been "turning things" on the camera this morning, I was pleased with the pictures I took yesterday with the lens.
John

Adam · 08-16-2015, 01:43 AM

Originally posted by Moonraker

Thanks for that, it is certainly an A, I will have to find out to use it on my K3, at the moment the camera wont fire with it on, I have been "turning things" on the camera this morning, I was pleased with the pictures I took yesterday with the lens.
John

Set the aperture ring to "A" and it will work just like any modern lens, except that you have to focus manually.

Adam
PentaxForums.com Webmaster (Site Usage Guide | Site Help | My Photography)

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Moonraker · 08-16-2015, 02:01 AM

That works fine thanks, also went onto youtube and Pentax forums and found a relevant video suggesting I go to menu, custom settings, drop down 4/27 - using aperture ring / enable, that works fine as well.

RMabo · 08-16-2015, 03:03 AM

With the lens in A-position, you have full access to the different exposure modes in the K-3 and also multisegment metering. When you use the aperture ring, your choices is limited because the camera lacks a connection to the aperture lever in the lens (it has to measure the opening, which happens when you press the green button). All Pentax DSLR's lacks the mechanical linkage to the aperture ring in the lens. But with lens at 'A', everything works just as an autofocus lens - except only manual focus. HyperProgram, P, Av, Tv, M etc...

Na Horuk · 08-16-2015, 04:33 AM

Originally posted by Moonraker

I bought second hand a Pentax 28mm lens, , the markings are smc PENTAX-A 1:2.8 28mm, serial No 5138600.

Morning! Sure, we can. This is a nice 28mm lens, covers full frame image circle. The A series that you have is supposed to be slightly better than the old M series version. The A-series also features the A-mode, which gives the camera full control over the lens' aperture.

Here is a tutorial on manual lenses, but your lens is not truly fully manual (there are two more good tutorial threads):
https://www.pentaxforums.com/forums/54-pentax-lens-articles/110657-how-use-me...k-x-k-7-a.html

So, go to Menu, very end you can Enable Aperture Ring. But you don't need to do this due to A-mode. What you really should do is just push the little button on the lens' aperture ring and slide it into A instead of one of the numbers (f2.8..f16). Once in A mode, you can select the aperture on the camera body. This also allows you to use Av or P or other modes.
If the camera asks you about the focal length, input the one listed on the front of the lens - 28mm. No multiplication or anything. This lets you use SR, shake reduction, so you can take handheld photos even with slightly longer shutter speeds.
Hm, what else.. Oh, you might want to buy a lens hood for this lens, like the JJC LH-SA49 (I use this on my M 28mm) or just a regular round or tulip shaped hood that fits the lens' threads. Don't buy a hood for telephoto or ultra wide angle, but get one for wide angle or normal lenses (on your camera, 28mm is more "normal" than "wide", but both hoods should be okay). You should not use an UV filter, but you might benefit from a polarizing filter (adds a little punch, can reduce reflections).
You can also use this lens in a more manual mode, if you switch it out of A on the aperture ring. You won't need this on a DSLR, but you might want it if you ever buy one of the older SLR cameras (ones older than A-series) or want to use the lens with certain macro accessories like bellows or extension tubes or lens reversal rings.

The lens doesn't feature AF, it was made before AF was invented, but you can still use Catch in focus with modern DSLRs. CiF, also known as focus trapping, gives you automatic triggering when focus is confirmed. There are some threads and even blog posts about this. You might enjoy it sometimes, as it gives something similar to AF even with MF lenses.

Btw, there is a thread for 28mm lenses. https://www.pentaxforums.com/forums/122-lens-clubs/168895-dslr-fun-28mm-club-any-28mm-lens.html
The thread is for 28mm lenses of all manufacturers, old or new, but its a fun thread, with some nice images, many posted by similar lenses as your own. In case you want inspiration.

hks_kansei · 08-16-2015, 04:39 AM

I have the same model lens, you shouldn't need to do anything to the camera to use it.

You must however set the lens aperture ring to the green "A" (to do this you'll need to press in the small button on the ring while turning to A, it will lock in place at A)

on the camera you'll need to turn the focus switch to manual, otherwise the camera may not let you take a shot until it thinks it's focussed.

it's a lovely lens, and I very much like mine.
However, I rarely use it on my digital SLR. I find on the DSLR it's not wide enough to be a decent wide, but not narrow enough to be a normal.
It's a great length for 35mm though.

Na Horuk · 08-16-2015, 04:47 AM

Originally posted by hks_kansei

on the camera you'll need to turn the focus switch to manual, otherwise the camera may not let you take a shot until it thinks it's focussed.

Oh yes, this can happen if you have certain AF settings. I think its AF, focus priority instead of shutter priority. Sometimes you want one, sometimes the other
And I'd say I enjoy 28mm on APSC DSLR. I find it to be normal enough

08-16-2015, 01:01 AM	#1
Moonraker New Member Join Date: May 2015 Photos: Gallery Posts: 4	Oldish lens? Morning everybody, I bought second hand a Pentax 28mm lens, , the markings are smc PENTAX-A 1:2.8 28mm, serial No 5138600. Can anyone out there give me any info on this lens please? John

08-16-2015, 01:13 AM	#2
Kerrowdown PEG Moderator Join Date: Aug 2008 Location: Highlands of Scotland... "Hold Infinity in the palm of your hand" - William Blake Photos: Gallery Posts: 57,833	Originally posted by Moonraker Can anyone out there give me any info on this lens please I would think it's going to be one of these two and probably the first as you mention A in the name, info right here on the forum. I hope this helps. SMC Pentax-A 28mm F2.8 Reviews - A Prime Lenses - Pentax Lens Reviews & Lens Database SMC Pentax-M 28mm F2.8 Reviews - M Prime Lenses - Pentax Lens Reviews & Lens Database

08-16-2015, 01:40 AM	#3
Moonraker New Member Join Date: May 2015 Photos: Gallery Posts: 4 Original Poster	Originally posted by Kerrowdown I would think it's going to be one of these two and probably the first as you mention A in the name, info right here on the forum. I hope this helps. SMC Pentax-A 28mm F2.8 Reviews - A Prime Lenses - Pentax Lens Reviews & Lens Database SMC Pentax-M 28mm F2.8 Reviews - M Prime Lenses - Pentax Lens Reviews & Lens Database Thanks for that, it is certainly an A, I will have to find out to use it on my K3, at the moment the camera wont fire with it on, I have been "turning things" on the camera this morning, I was pleased with the pictures I took yesterday with the lens. John

08-16-2015, 01:43 AM	#4
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,597	Originally posted by Moonraker Thanks for that, it is certainly an A, I will have to find out to use it on my K3, at the moment the camera wont fire with it on, I have been "turning things" on the camera this morning, I was pleased with the pictures I took yesterday with the lens. John Set the aperture ring to "A" and it will work just like any modern lens, except that you have to focus manually. Adam PentaxForums.com Webmaster (Site Usage Guide \| Site Help \| My Photography) PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating or purchasing one of our Pentax eBooks. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

08-16-2015, 02:01 AM	#5
Moonraker New Member Join Date: May 2015 Photos: Gallery Posts: 4 Original Poster	That works fine thanks, also went onto youtube and Pentax forums and found a relevant video suggesting I go to menu, custom settings, drop down 4/27 - using aperture ring / enable, that works fine as well.

08-16-2015, 03:03 AM	#6
RMabo Veteran Member Join Date: Jul 2007 Location: Sweden Posts: 845	With the lens in A-position, you have full access to the different exposure modes in the K-3 and also multisegment metering. When you use the aperture ring, your choices is limited because the camera lacks a connection to the aperture lever in the lens (it has to measure the opening, which happens when you press the green button). All Pentax DSLR's lacks the mechanical linkage to the aperture ring in the lens. But with lens at 'A', everything works just as an autofocus lens - except only manual focus. HyperProgram, P, Av, Tv, M etc...

08-16-2015, 04:33 AM	#7
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	Originally posted by Moonraker I bought second hand a Pentax 28mm lens, , the markings are smc PENTAX-A 1:2.8 28mm, serial No 5138600. Morning! Sure, we can. This is a nice 28mm lens, covers full frame image circle. The A series that you have is supposed to be slightly better than the old M series version. The A-series also features the A-mode, which gives the camera full control over the lens' aperture. Here is a tutorial on manual lenses, but your lens is not truly fully manual (there are two more good tutorial threads): https://www.pentaxforums.com/forums/54-pentax-lens-articles/110657-how-use-me...k-x-k-7-a.html So, go to Menu, very end you can Enable Aperture Ring. But you don't need to do this due to A-mode. What you really should do is just push the little button on the lens' aperture ring and slide it into A instead of one of the numbers (f2.8..f16). Once in A mode, you can select the aperture on the camera body. This also allows you to use Av or P or other modes. If the camera asks you about the focal length, input the one listed on the front of the lens - 28mm. No multiplication or anything. This lets you use SR, shake reduction, so you can take handheld photos even with slightly longer shutter speeds. Hm, what else.. Oh, you might want to buy a lens hood for this lens, like the JJC LH-SA49 (I use this on my M 28mm) or just a regular round or tulip shaped hood that fits the lens' threads. Don't buy a hood for telephoto or ultra wide angle, but get one for wide angle or normal lenses (on your camera, 28mm is more "normal" than "wide", but both hoods should be okay). You should not use an UV filter, but you might benefit from a polarizing filter (adds a little punch, can reduce reflections). You can also use this lens in a more manual mode, if you switch it out of A on the aperture ring. You won't need this on a DSLR, but you might want it if you ever buy one of the older SLR cameras (ones older than A-series) or want to use the lens with certain macro accessories like bellows or extension tubes or lens reversal rings. The lens doesn't feature AF, it was made before AF was invented, but you can still use Catch in focus with modern DSLRs. CiF, also known as focus trapping, gives you automatic triggering when focus is confirmed. There are some threads and even blog posts about this. You might enjoy it sometimes, as it gives something similar to AF even with MF lenses. Btw, there is a thread for 28mm lenses. https://www.pentaxforums.com/forums/122-lens-clubs/168895-dslr-fun-28mm-club-any-28mm-lens.html The thread is for 28mm lenses of all manufacturers, old or new, but its a fun thread, with some nice images, many posted by similar lenses as your own. In case you want inspiration.

08-16-2015, 04:39 AM	#8
hks_kansei Veteran Member Join Date: Jun 2012 Posts: 834	I have the same model lens, you shouldn't need to do anything to the camera to use it. You must however set the lens aperture ring to the green "A" (to do this you'll need to press in the small button on the ring while turning to A, it will lock in place at A) on the camera you'll need to turn the focus switch to manual, otherwise the camera may not let you take a shot until it thinks it's focussed. it's a lovely lens, and I very much like mine. However, I rarely use it on my digital SLR. I find on the DSLR it's not wide enough to be a decent wide, but not narrow enough to be a normal. It's a great length for 35mm though.

08-16-2015, 04:47 AM	#9
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	Originally posted by hks_kansei on the camera you'll need to turn the focus switch to manual, otherwise the camera may not let you take a shot until it thinks it's focussed. Oh yes, this can happen if you have certain AF settings. I think its AF, focus priority instead of shutter priority. Sometimes you want one, sometimes the other And I'd say I enjoy 28mm on APSC DSLR. I find it to be normal enough