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10-04-2020, 05:26 PM - 2 Likes   #1
Harbaror
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k1000 focus question beginner

Hi,

Thank you again for all the help I have received so far.
I have yet a question needing answer.

As a beginner, I am trying to understand how my camera work, K1000 (50mm f1.4 lens)
This question is regarding the Focus.

When I point my camera to where I want the focus to be, and start turning the focus ring, I can see what is in and out of focus. As I have yet to develop my first film, I wanted to know if what I see in the viewfinder is what the picture will look like? Strange question I am sure.

Thank you in advance.

10-04-2020, 06:01 PM   #2
maw
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QuoteOriginally posted by Harbaror Quote
As a beginner, I am trying to understand how my camera work, K1000 (50mm f1.4 lens)
This question is regarding the Focus.

When I point my camera to where I want the focus to be, and start turning the focus ring, I can see what is in and out of focus. As I have yet to develop my first film, I wanted to know if what I see in the viewfinder is what the picture will look like? Strange question I am sure.
Hi Harbaror,

Congratulations on the purchase, K1000 one of the reflex cameras that have made the history of Pentax,

The question you ask is yes, basically what you see in focus inside the viewfinder should be in focus (sharp) in the final print or slide.
But it is all related to the optics you use, if you use the classic 50mm you will have less depth of field (PDC) than a 28mm and more than a 100mm, i.e.
the sharp area will be greater or less depending on the focal length and aperture.

E.g. with a 50mm at f/11 you will have a sharper area than with the same lens with f/4 for example.

This is in summary the concept, then there are several other factors to consider, the focal length, the aperture, the distance from the subject.

Ciao Mario
10-04-2020, 06:12 PM   #3
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That is not that simple to answer.
What you get in the captured image is slightly more than what you see in the viewfinder. You are actually seeing about 91% of the captured image. In my opinion it is hardy noticeable on everyday use.
Now, in terms of the image itself, you are always looking thru the lens wide open. (Open metering). Only when you take the picture the lens diaphragm closes to the selected aperture. This means you can not see the actual depth of field (how much of the image is in focus vs out of focus) you will get in your final image. Some other cameras have Depth Of Field preview which is basically closing down the lens to the selected aperture.
Now, what you are seeing may be totally different from what you expose. If you underexpose your shot, the resulting image will be dark. Similarly if you overexpose it may be too bright.
So there is a lot going on between what you see and what you get. That's part of the fun. Learning to capture exactly what you were seeing.
Hope this helps.

Thanks,
10-04-2020, 06:13 PM   #4
Harbaror
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Thank you for that, it does make a lot of sense, and helps me a lot.

So just to be sure, cause Im new to this.
If I were to take a picture of let's say, a lake with trees around, and set my camera to f11 and shutter speed accordingly, and took the same picture with f4 and shutter speed again accordingly, and not touch the focus ring at all, the sharpness would not be the same? The focus wouldn't be the same either? is that correct?

So how would I know what might be the better result for my Lake photo?? hehe

Thank you

---------- Post added 10-04-20 at 06:17 PM ----------



---------- Post added 10-04-20 at 06:18 PM ----------

QuoteOriginally posted by ismaelg Quote
That is not that simple to answer.
What you get in the captured image is slightly more than what you see in the viewfinder. You are actually seeing about 91% of the captured image. In my opinion it is hardy noticeable on everyday use.
Now, in terms of the image itself, you are always looking thru the lens wide open. (Open metering). Only when you take the picture the lens diaphragm closes to the selected aperture. This means you can not see the actual depth of field (how much of the image is in focus vs out of focus) you will get in your final image. Some other cameras have Depth Of Field preview which is basically closing down the lens to the selected aperture.
Now, what you are seeing may be totally different from what you expose. If you underexpose your shot, the resulting image will be dark. Similarly if you overexpose it may be too bright.
So there is a lot going on between what you see and what you get. That's part of the fun. Learning to capture exactly what you were seeing.
Hope this helps.

Thanks,
Wow, yes this helps greatly too.
I think and guess the best way to understand this is to take test shots of the same exposure with different settings and compare them to learn...

I understand and think I get the over and under exposure, but the DOF and focus seems harder to understand seems the K1000 doesn't have a DOF preview settings. So know what will and will not be in focus is a challange.

thanks

10-04-2020, 06:30 PM   #5
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You don't have to guess.
Your lens aperture ring should have a mark at the top center near where it mounts to the body. On either side of that mark there are pairs of numbers, maybe, 4, 11, 16, 22. On the barrel of the lens or the focus ring, there is usually a feet/meter measure maybe marked 1meter , but also marked with the infinity symbol, possibly with lines running down to the number pair on the aperture ring. This shows you the size of the Depth of field at given aperture so you can see what would be in focus in front or behind your in focus subject.
10-04-2020, 06:50 PM   #6
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Hello,

The bigger the aperture (smaller f number) the less depth of field. Conversely the smaller aperture (larger f number) the more depth of field. But that will also depend on distance to subject, focal length etc.
The bottom line is that at bigger apertures, focusing is more critical because your in focus area is smaller.

This may not be the best example, but here is a test I did a while ago testing a 400mm lens.
At f6.3 you can see that only the wheel is in focus.


At f11, the tire and the white iron gate behind start to be in focus.


At f32 part of the road behind and part of the gate in front of the car begin to be in focus.


Now, this is a very specific test for a very specific lens (400mm f6.3) Your lens will follow the same depth of field "physics" but the size of the area in focus will behave differently.

Now there is a scale on the lens that will tell you the depth of field based on aperture. But that's another story. Let me see if I find something I wrote a while ago about that and also hyperfocal focusing.

I hope this helps instead of confusing you more

Thanks,
10-04-2020, 06:50 PM   #7
Harbaror
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QuoteOriginally posted by robgski Quote
You don't have to guess.
Your lens aperture ring should have a mark at the top center near where it mounts to the body. On either side of that mark there are pairs of numbers, maybe, 4, 11, 16, 22. On the barrel of the lens or the focus ring, there is usually a feet/meter measure maybe marked 1meter , but also marked with the infinity symbol, possibly with lines running down to the number pair on the aperture ring. This shows you the size of the Depth of field at given aperture so you can see what would be in focus in front or behind your in focus subject.
I did know about those markings, but wasn't very sure about how they worked, I wasn't sure if the metering was from the camera itself or where it was actually measured. But with the help of your comment, and a quick google search, I now understand that the metering is from the focus point and inward/ outward from that point. (is that correct I hope).

Thank you

---------- Post added 10-04-20 at 06:53 PM ----------

QuoteOriginally posted by ismaelg Quote
Hello,

The bigger the aperture (smaller f number) the less depth of field. Conversely the smaller aperture (larger f number) the more depth of field. But that will also depend on distance to subject, focal length etc.
The bottom line is that at bigger apertures, focusing is more critical because your in focus area is smaller.

This may not be the best example, but here is a test I did a while ago testing a 400mm lens.
At f6.3 you can see that only the wheel is in focus.


At f11, the tire and the white iron gate behind start to be in focus.


At f32 part of the road behind and part of the gate in front of the car begin to be in focus.


Now, this is a very specific test for a very specific lens (400mm f6.3) Your lens will follow the same depth of field "physics" but the size of the area in focus will behave differently.
I hope this helps instead of confusing you more

Thanks,
Wonderful example, and what I was looking for.
Makes a lot of sense and makes it easier to understand how I will shoot my photos.

Greatly appreciated.

10-04-2020, 11:41 PM   #8
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Yes, DOF will be either side of the focus point. If you focus on your target the index line on the lens will give you range. For example you focus on something 10 meters away. When you look at the lens ithe index mark will be level with the 10m mark on the lens scale. The small f stop numbers either side of the index mark will tell you how deep the focus is. For example the f4 mark might be mid point between 5 and 10 meters on the near focus and the between 10 and 30 meters on the far focus.

So reading the scale on the lens tells you that everything from approximately 7.5 meters to 20 meters will be in focus. After a while you just know from experience what you might need and in any event conditions will dictate whats possible which limits the choice.
For example if you are out on a bright sunny day with a fairly fast film like ASA 400 the chances are you will be limited to only the more closed apertures, you probably wont be able to get a shutter speed fast enough to go much under f8. On an overcast or dull day with a slow film like ASA 125 you may not be able to shoot much over f8.

Landscapes are often easiest as you will often be using infinity focus so its not so much of a worry. If you want to pick an object from a crowd like a single flower amongst many then thats when you can use a wide open aperture at f1.7 to have just the target in focus and everything else blurred out.

For objects out at infinity eg objects very far away, so long as the lens is focused on them will mean that everything pretty much will be in focus unless any very close objects obscure part of the view.

As mentioned some cameras have a DOF preview which stops the lens down so you can see whats in focus but I never find it helpful, usually at small apertures the image becomes so dark on the focus screen its very hard to tell whats happening. Obviously the image wont be dark when you take the shot because the shutter speed will be slower so that the film is more exposed to give something close to the brightness you are seeing.

Film takes some getting used to and its a good idea when you start to find a film you like for color or black and white contrast etc and then stick with that film so you get used to how to get good shots from it otherwise changing films all the time means you are trying to learn with an inconsistent base....bit like teaching someone to paint and every time they turn up for a lesson you make them work with different paints, materials like oil, acrylic, water colurs etc. They need to master a medium before trying new things.

Last edited by Astro-Baby; 10-04-2020 at 11:49 PM.
10-05-2020, 07:23 AM   #9
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QuoteOriginally posted by Harbaror Quote
Hi,

Thank you again for all the help I have received so far.
I have yet a question needing answer.

As a beginner, I am trying to understand how my camera work, K1000 (50mm f1.4 lens)
This question is regarding the Focus.

When I point my camera to where I want the focus to be, and start turning the focus ring, I can see what is in and out of focus. As I have yet to develop my first film, I wanted to know if what I see in the viewfinder is what the picture will look like? Strange question I am sure.

Thank you in advance.
Take a look at the K1000 manual, it explains DOF and other things that may help you out. When I got my first Pentax camera, way before the internet was around, the manual was a good source of info for a beginner like myself.

Pentax k1000 manual

Phil.
10-05-2020, 07:53 PM   #10
Harbaror
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QuoteOriginally posted by Astro-Baby Quote
Yes, DOF will be either side of the focus point. If you focus on your target the index line on the lens will give you range. For example you focus on something 10 meters away. When you look at the lens ithe index mark will be level with the 10m mark on the lens scale. The small f stop numbers either side of the index mark will tell you how deep the focus is. For example the f4 mark might be mid point between 5 and 10 meters on the near focus and the between 10 and 30 meters on the far focus.

So reading the scale on the lens tells you that everything from approximately 7.5 meters to 20 meters will be in focus. After a while you just know from experience what you might need and in any event conditions will dictate whats possible which limits the choice.
For example if you are out on a bright sunny day with a fairly fast film like ASA 400 the chances are you will be limited to only the more closed apertures, you probably wont be able to get a shutter speed fast enough to go much under f8. On an overcast or dull day with a slow film like ASA 125 you may not be able to shoot much over f8.

Landscapes are often easiest as you will often be using infinity focus so its not so much of a worry. If you want to pick an object from a crowd like a single flower amongst many then thats when you can use a wide open aperture at f1.7 to have just the target in focus and everything else blurred out.

For objects out at infinity eg objects very far away, so long as the lens is focused on them will mean that everything pretty much will be in focus unless any very close objects obscure part of the view.

As mentioned some cameras have a DOF preview which stops the lens down so you can see whats in focus but I never find it helpful, usually at small apertures the image becomes so dark on the focus screen its very hard to tell whats happening. Obviously the image wont be dark when you take the shot because the shutter speed will be slower so that the film is more exposed to give something close to the brightness you are seeing.

Film takes some getting used to and its a good idea when you start to find a film you like for color or black and white contrast etc and then stick with that film so you get used to how to get good shots from it otherwise changing films all the time means you are trying to learn with an inconsistent base....bit like teaching someone to paint and every time they turn up for a lesson you make them work with different paints, materials like oil, acrylic, water colurs etc. They need to master a medium before trying new things.
Thank you so much for the wonderful advice. I am starting to get the big picture ;-) And this will help me greatly when trying out.

having said that, first EVER roll of 36 photos finished. Lets see how it turns out. I'll post some of the good ones on the forum for so hard critics.

thank you

---------- Post added 10-05-20 at 07:54 PM ----------

QuoteOriginally posted by gofour3 Quote
Take a look at the K1000 manual, it explains DOF and other things that may help you out. When I got my first Pentax camera, way before the internet was around, the manual was a good source of info for a beginner like myself.

Pentax k1000 manual

Phil.
Thanks, it sure makes a lot of sense to read the manual. I did have look at it briefly, I will make sure to ready thoroughly one more time.

regards
10-06-2020, 03:27 AM   #11
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QuoteOriginally posted by Astro-Baby Quote
As mentioned some cameras have a DOF preview which stops the lens down so you can see whats in focus but I never find it helpful, usually at small apertures the image becomes so dark on the focus screen its very hard to tell whats happening.
I'm glad I'm not the only one. The KM, from which the K1000 was derived, did have a depth of field [DoF] preview lever, and the cameras I now have also do, but I never use it. It could be useful when taking close-ups of brightly lit subjects in rooms with subdued lighting.

Regarding the DoF scales on old manual focus lenses, they are supposed to be applicable for normal sized prints viewed at normal distances, whatever those are. Of course there is no step change of sharpness at those distances. The sharpness is only perfect (or optimum, as nothing is perfect) at one distance and it deteriorates as you look away from that distance in the photo, and the larger the aperture the more rapid the deterioration is. This is Laws of Physics stuff, independent of camera brand etc.

Interestingly the human eye has a very narrow and shallow field of sharpness. We make up for it by moving our eyes around the scene and building the whole picture in the brain. We do have a very wide field of view, but fuzzy outside the centre; it is to detect movement at the edges that may be a threat (or opportunity).

Historically. artists usually painted their whole canvas "in focus", especially before photography unwittingly showed a new style. They often painted at resolutions beyond that of the human eye at normal viewing distance, but of course viewers in galleries often step closer for detailed examination. Even for photographs - I went to the London exhibition of Ansel Adams photos in the 1980s and saw an older gent examining the bottom corners of the prints with a large magnifying glass!

Some Pre-Raphaelite painters were reputed to paint with a single hair on their brush - an exageration though.

The Scapegoat

by Holman Hunt, Pre-Raphaelite School, 1856


Last edited by Lord Lucan; 10-06-2020 at 03:31 AM. Reason: Tpyo
10-06-2020, 07:37 PM   #12
Harbaror
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Thank you for that. It contributes in helping me understand the concept of DoF. Now I just have to TRY it out and see the result after development.

Regards
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