mz 7 smc m2.8 28mm
Posted 20/04/2004 - 20:04
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Sorry also meant to ask just what difference centre-weighted metering makes when compared to MZ7's matrix metering.
Thanks
grahamb
Thanks
grahamb
Posted 20/04/2004 - 23:23
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Centre weighted metering measures the whole screen area, but with the emphasis on the centre of the frame. In experienced hands, this is perfectly predictable and quite satisfactory. Large areas of sky will upset the readings and cause underexposure, but if this is understood compensation can be made.
Matrix metering measures many areas of the screen and the camera's algorithms decide what you are photographing and adjust exposure accordingly. In the example of sky, bright areas at the top of a picture may well be interpreted as sky and the camera could adjust exposure accordingly. The snag is that the photographer does not know what the camera is thinking so although suitable for less experienced users, I question the need for matrix metering in experienced hands.
Personally I use centre weighted and spot metering, very often with manual exposure mode as well.
Matrix metering measures many areas of the screen and the camera's algorithms decide what you are photographing and adjust exposure accordingly. In the example of sky, bright areas at the top of a picture may well be interpreted as sky and the camera could adjust exposure accordingly. The snag is that the photographer does not know what the camera is thinking so although suitable for less experienced users, I question the need for matrix metering in experienced hands.
Personally I use centre weighted and spot metering, very often with manual exposure mode as well.
Best regards, John
Posted 21/04/2004 - 21:00
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Useful info, thanks johnriley.
When I get my M 28mm 2.8 (this week I hope) will I have aperture priority and manual only or are other combinations possible with the MZ7?
I read on Stan's Pentax site to keep away from the M 28mm 2.8, any comments on this view?
Thanks again
Regards
grahamb
When I get my M 28mm 2.8 (this week I hope) will I have aperture priority and manual only or are other combinations possible with the MZ7?
I read on Stan's Pentax site to keep away from the M 28mm 2.8, any comments on this view?
Thanks again
Regards
grahamb
Posted 21/04/2004 - 21:01
Link
Useful info, thanks johnriley.
When I get my M 28mm 2.8 (this week I hope) will I have aperture priority and manual only or are other combinations possible with the MZ7?
I read on Stan's Pentax site to keep away from the M 28mm 2.8, any comments on this view?
Thanks again
Regards
grahamb
When I get my M 28mm 2.8 (this week I hope) will I have aperture priority and manual only or are other combinations possible with the MZ7?
I read on Stan's Pentax site to keep away from the M 28mm 2.8, any comments on this view?
Thanks again
Regards
grahamb
Posted 21/04/2004 - 23:16
Link
M lenses only offer manual and aperture-priority operation. However, most people don't find this much of a drawback in practice.
Stan's site draws on the experience of some hyper-critical characters, many of whom use the best lenses Pentax has to offer. In other words, the M lenses are being compared to optics that cost much more, and which are often very hard to find.
In the real world, the M 28mm f2.8 is a fine lens that will give you excellent service. I've no complaints with mine.
Stan's site draws on the experience of some hyper-critical characters, many of whom use the best lenses Pentax has to offer. In other words, the M lenses are being compared to optics that cost much more, and which are often very hard to find.
In the real world, the M 28mm f2.8 is a fine lens that will give you excellent service. I've no complaints with mine.
Posted 22/04/2004 - 10:47
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Thanks for your comments, George.
I also have a FA 1.7 50mm, which is excellent. But as I'm a novice I have perhaps a stupid question. Is the scale with 22 16 8 between the distance scale and PENTAX 50 a depth of field scale? The instructions only mention infra-red so I'm not sure. If so, and if I split the infinity symbol at 22 ,for example, and read off at the third mark on the right, about 1.7m, is this half the hyperfocal distance and the distance from which everything to infinity will be sharp? Presuming aperture to be F22, of course.
Any advice, comments would be great.
Thanks.
I also have a FA 1.7 50mm, which is excellent. But as I'm a novice I have perhaps a stupid question. Is the scale with 22 16 8 between the distance scale and PENTAX 50 a depth of field scale? The instructions only mention infra-red so I'm not sure. If so, and if I split the infinity symbol at 22 ,for example, and read off at the third mark on the right, about 1.7m, is this half the hyperfocal distance and the distance from which everything to infinity will be sharp? Presuming aperture to be F22, of course.
Any advice, comments would be great.
Thanks.
Posted 22/04/2004 - 15:34
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Hi Grahamb,
I would certainly agree with George's comments having had experience of 4 of the Pentax 28mm lenses. As a matter of interest I have put my thoughts on them below. As George says many of the comments in Stan's are a bit hyper critical and to a certain extent based on benchmark tests rather than "normal" usage. I will reserve my opinion on some of the AF lenses but whilst there are differences in the quality of the MF lenses, they are all nonetheless capable of excellent results. To see the difference you would have to be producing some pretty large display prints. IMHO the quality of the film is going to make much more difference in everyday usage. The only exception to this is the A series Takumar lenses. These have a much lesser quality coating and although they are still capable of good results, I would tend to avoid them.
As a matter of interest I have or have had the 2.8M, the 2.0A, the 3.5K and the 2.8F. In everyday usage, I have found little difference in optical performance between them. To me the handlig and balance are far more important. I originally had the 2.8M. Whilst I was quite happy with this, it went to my sister when I had the oportunity to get the 2.0A at a fantastic price. A lot of my work was air-to-air photog and this meant working with thin gloves on. For this reason I find I often prefer both the K series cameras and lenses. The 2.8M gave me good results and a bright finder compared with a 24-50 zoom which made focusing and their usage much easier. The only thing I didn't like about the 2.8M was that it was a fairly "thin" lens and didn't balance that well on a KX. The A solved this and gave a brighter finder and narrower depth of field for focus albeit at a price. Having moved toward AF (damn eyesight), I got a 2.8F (secondhand as usual). this is the same construction as the M. In hindsight, I think I should have waited to try and get an FA. Supposidly it is better optically but the bis plus in my mind is that the focus ring is smoth and wider similar to your 1.7 and this makes for better handling. To round things off, I recently got a 3.5K for a couple of pounds because of a lazy iris. This is the one that Stan's site reckon is the sharpest and best of the 28's. Having cleaned the oil off the iris operating linkage!, it works perfectly. I prefer it to the 2.8M because of the size and handling but to be honest, I can't tell any diference in performance in prints up to 14x11 and that's as large as I normaly go. So, although, I find Stan's a wonderful resource, the handling and the price are more important IMHO. If these were the same, then I would worry about pure optical performance.
In answer to your other question the scale is the depth of field scale. Say you were working at F11. If you put the infinity mark against the 11 mark on the left, the in theory everything wil be in focus up to the distance mark against the righthand 11 mark. With a wide angle this can be very useful for candids. If you want to check depth of field and haven't got a depth of field preview, focus as normal. Again assuming F11, then everything between the distances against the "11"s should be in focus.
Hope this helps
Kim
I would certainly agree with George's comments having had experience of 4 of the Pentax 28mm lenses. As a matter of interest I have put my thoughts on them below. As George says many of the comments in Stan's are a bit hyper critical and to a certain extent based on benchmark tests rather than "normal" usage. I will reserve my opinion on some of the AF lenses but whilst there are differences in the quality of the MF lenses, they are all nonetheless capable of excellent results. To see the difference you would have to be producing some pretty large display prints. IMHO the quality of the film is going to make much more difference in everyday usage. The only exception to this is the A series Takumar lenses. These have a much lesser quality coating and although they are still capable of good results, I would tend to avoid them.
As a matter of interest I have or have had the 2.8M, the 2.0A, the 3.5K and the 2.8F. In everyday usage, I have found little difference in optical performance between them. To me the handlig and balance are far more important. I originally had the 2.8M. Whilst I was quite happy with this, it went to my sister when I had the oportunity to get the 2.0A at a fantastic price. A lot of my work was air-to-air photog and this meant working with thin gloves on. For this reason I find I often prefer both the K series cameras and lenses. The 2.8M gave me good results and a bright finder compared with a 24-50 zoom which made focusing and their usage much easier. The only thing I didn't like about the 2.8M was that it was a fairly "thin" lens and didn't balance that well on a KX. The A solved this and gave a brighter finder and narrower depth of field for focus albeit at a price. Having moved toward AF (damn eyesight), I got a 2.8F (secondhand as usual). this is the same construction as the M. In hindsight, I think I should have waited to try and get an FA. Supposidly it is better optically but the bis plus in my mind is that the focus ring is smoth and wider similar to your 1.7 and this makes for better handling. To round things off, I recently got a 3.5K for a couple of pounds because of a lazy iris. This is the one that Stan's site reckon is the sharpest and best of the 28's. Having cleaned the oil off the iris operating linkage!, it works perfectly. I prefer it to the 2.8M because of the size and handling but to be honest, I can't tell any diference in performance in prints up to 14x11 and that's as large as I normaly go. So, although, I find Stan's a wonderful resource, the handling and the price are more important IMHO. If these were the same, then I would worry about pure optical performance.
In answer to your other question the scale is the depth of field scale. Say you were working at F11. If you put the infinity mark against the 11 mark on the left, the in theory everything wil be in focus up to the distance mark against the righthand 11 mark. With a wide angle this can be very useful for candids. If you want to check depth of field and haven't got a depth of field preview, focus as normal. Again assuming F11, then everything between the distances against the "11"s should be in focus.
Hope this helps
Kim
Posted 23/04/2004 - 21:40
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Hi Kim,
Yes, thanks that helps a lot.
Just one thing, you said if I don't have depth of field preview (I don't) to just focus as normal. Surely then I'd no longer be focusing at the correct distance, or do you mean I focus normally to see DOF and then re-focus on the DOF scale markings? I'm a little confused here
One more point, I heard that if you focus a little back from infinity when using a zoom or telephoto lens that has no depth of field scale, you can use the hyperfocal distance. Just how much back from infinity and how you calculate it with the sparse markings available is my question. Your views on this?
Regards
Grahamb
Yes, thanks that helps a lot.
Just one thing, you said if I don't have depth of field preview (I don't) to just focus as normal. Surely then I'd no longer be focusing at the correct distance, or do you mean I focus normally to see DOF and then re-focus on the DOF scale markings? I'm a little confused here
One more point, I heard that if you focus a little back from infinity when using a zoom or telephoto lens that has no depth of field scale, you can use the hyperfocal distance. Just how much back from infinity and how you calculate it with the sparse markings available is my question. Your views on this?
Regards
Grahamb
Posted 23/04/2004 - 23:05
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As a rule of thumb for hyperfocal distance, focus one third of the distance into a scene. So, if you want everything sharp from foreground to background, don't focus on infinity and don't focus on the nearest point, but one third of the way in between. Using a small aperture this will work most of the time.
Best regards, John
Posted 24/04/2004 - 23:08
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Thanks johnriley, now I know how to do it.
What a great forum this is, lots of knowledgeable people willing to reply and help out.
Regards
grahamb
What a great forum this is, lots of knowledgeable people willing to reply and help out.
Regards
grahamb
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11 posts
22 years
Germany
I'm new here and have read lots of interesting and helpful posts.
Can anyone give me any tips etc regarding using an mz7 with a smc m 2.8 28mm lens. I understand that only centre-weighted average metering is possible. Is there anything else I should know?
Thanks in advance.
grahamb