All Forum Comments
Thank you for that Peter you can see them bigger there and really admire your battle against noise
Comment by Anvh posted on K20D + DA*300mm @ ISO 6400 - Does it cut the mustard? at 15/07/2009 - 23:14
So is anyone going outside to take some photos tomorrow?
Comment by Anvh posted on K20D versus Nikon D300 at 15/07/2009 - 23:12
Malo1961 wrote:
Why would you?? It's common knowledge that noise always is more pronounced when viewed on screen. Prints tend to be far more forgiving to alleged noise issues, then most people would expect. Thats one of the reasons the pixel peepers and measurebaters of this world are having such a good time. Like in the film days. If grain is a issue, work with it to your advantage. But then.....more and more people are starting of as a first timer in photography the digital way. Most of them take all that for granted not even knowing something like film even existed. I know......it's a bit overrated now, but ask me again in ten years. Sign of the Times........
Martin.
Maybe but by resizing a 4672 x 3104 to 800 x 532 you also eliminate a lot of noise and make the image appear sharper.Why would you?? It's common knowledge that noise always is more pronounced when viewed on screen. Prints tend to be far more forgiving to alleged noise issues, then most people would expect. Thats one of the reasons the pixel peepers and measurebaters of this world are having such a good time. Like in the film days. If grain is a issue, work with it to your advantage. But then.....more and more people are starting of as a first timer in photography the digital way. Most of them take all that for granted not even knowing something like film even existed. I know......it's a bit overrated now, but ask me again in ten years. Sign of the Times........
Martin.
Here is some fun for you, these photos are taken at iso6400 with the K20D, D300 and a700 now which one is which?
I've deleted the EXIF data so no cheating
#1
[IMG]http://i282.photobucket.com/albums/kk244/Anvh/ISO6400-X.jpg[/IMG]
#2
[IMG]http://i282.photobucket.com/albums/kk244/Anvh/ISO6400-XX.jpg[/IMG]
#3
[IMG]http://i282.photobucket.com/albums/kk244/Anvh/ISO6400-XXX.jpg[/IMG]
Comment by Anvh posted on K20D + DA*300mm @ ISO 6400 - Does it cut the mustard? at 15/07/2009 - 23:01
But these are 800px image not really suited for print shall we say
Let's say we go for 6"x8" print on 300ppi that's 1795 x 2398 px or 4.3mp if we should do it probable.
Let's say we go for 6"x8" print on 300ppi that's 1795 x 2398 px or 4.3mp if we should do it probable.
Comment by Anvh posted on K20D + DA*300mm @ ISO 6400 - Does it cut the mustard? at 15/07/2009 - 20:10
Okay John here is the drawing.
[IMG]http://i282.photobucket.com/albums/kk244/Anvh/Lens.jpg[/IMG]
All the lenses have the same focal length and have the same magnification on the angle of view/ film size is differend.
So my thought was if you used the last lens for example and use that on different formats you get this image.
[IMG]http://i282.photobucket.com/albums/kk244/Anvh/Lens2.jpg[/IMG]
To get the same image surface you of course need to get another focal length for the smaller formats.
But the image the smaller format capture now is a part of the same image the large format capture so you can say that the image have the same properties beside the angle of view right?
By saying that you're saying that the influence the lens have on the DOF is for all the formats the same.
[IMG]http://i282.photobucket.com/albums/kk244/Anvh/Lens.jpg[/IMG]
All the lenses have the same focal length and have the same magnification on the angle of view/ film size is differend.
So my thought was if you used the last lens for example and use that on different formats you get this image.
[IMG]http://i282.photobucket.com/albums/kk244/Anvh/Lens2.jpg[/IMG]
To get the same image surface you of course need to get another focal length for the smaller formats.
But the image the smaller format capture now is a part of the same image the large format capture so you can say that the image have the same properties beside the angle of view right?
By saying that you're saying that the influence the lens have on the DOF is for all the formats the same.
Comment by Anvh posted on The impact the sensor size has on the lens at 15/07/2009 - 19:33
Good luck with the sheeps Bresail
Glad to see that everyone is on one line though
ttk wrote:
Spot on Stefan, Thats the way I have mine works a treat.
I use the PDF in the link to get to these settings Spot on Stefan, Thats the way I have mine works a treat.
Glad to see that everyone is on one line though
Comment by Anvh posted on Printing from Canon MP 610 at 15/07/2009 - 19:04
John I see your point but you don't see my point I believe.
The lens in this case is 85mm so if the focus distance and the length from the lens to the film keeps the same we can say that the magnification of the lens is the same regardless the crop the film is making.
You do agree on the right?
A macro lens at 1:1 magnification give that magnification regardless the film size.
I'm now completely forgetting that the image they produce are not the same since the angle of view is different but besides that everything is the same. So the only thing effecting the DOF now is the size of the sensor.
another approach...
A 85mm f/1.4 at 10m focus on 10x8 film gives a DOF 9.14m
Explain to me why the same lens at the same settings give another DOF depending on the size of the film.
The lens in this case is 85mm so if the focus distance and the length from the lens to the film keeps the same we can say that the magnification of the lens is the same regardless the crop the film is making.
You do agree on the right?
A macro lens at 1:1 magnification give that magnification regardless the film size.
I'm now completely forgetting that the image they produce are not the same since the angle of view is different but besides that everything is the same. So the only thing effecting the DOF now is the size of the sensor.
another approach...
A 85mm f/1.4 at 10m focus on 10x8 film gives a DOF 9.14m
Explain to me why the same lens at the same settings give another DOF depending on the size of the film.
Comment by Anvh posted on The impact the sensor size has on the lens at 15/07/2009 - 18:39
Okay I made a screen shot for you settings what you need to change and do.
Here is the screen shot I will guide you through it. link
First set the photoshop window to the right with the right settings.
Makes sure that the ones with the blue arrows are the same.
The middle blue arrow pointing at "printer profile" - "ILFORD prenium glossy...." need to be change to the paper you are using.
MP is matte paper
GP is glossy
All the abbreviation are in the PDF document i linked you to above.
Now click on "page setup" it will open the printer window you see at the top left.
First go under effect and uncheck everything so that you've complete control.
Go back to the main tab select the right paper under "media type"
Set quality to high or go to custom and set it to fine and defusion.
Now set color/intensity to manual and click on set and aply the same settings as my.
Now you've you're colours set up correctly, you can go to page setup and apply borderless printing and things like that.
ps. Simon has it precisely the same as me.
Here is the screen shot I will guide you through it. link
First set the photoshop window to the right with the right settings.
Makes sure that the ones with the blue arrows are the same.
The middle blue arrow pointing at "printer profile" - "ILFORD prenium glossy...." need to be change to the paper you are using.
MP is matte paper
GP is glossy
All the abbreviation are in the PDF document i linked you to above.
Now click on "page setup" it will open the printer window you see at the top left.
First go under effect and uncheck everything so that you've complete control.
Go back to the main tab select the right paper under "media type"
Set quality to high or go to custom and set it to fine and defusion.
Now set color/intensity to manual and click on set and aply the same settings as my.
Now you've you're colours set up correctly, you can go to page setup and apply borderless printing and things like that.
ps. Simon has it precisely the same as me.
Comment by Anvh posted on Printing from Canon MP 610 at 15/07/2009 - 18:21
The DOF matter is going further here link
Just want to carry it on to see if I got it right in my mind since John suggest I've it wrong so I probable am though but don't know why yet.
Just want to carry it on to see if I got it right in my mind since John suggest I've it wrong so I probable am though but don't know why yet.
Comment by Anvh posted on k200 vs k20 at 15/07/2009 - 18:04
Since John and I went of topic in a thread lets continue here.
The quotations of the post came from here after all.
here is our conversation so far.
I chose the same lens setup (FA*85 at 10mm focus for both cameras) so that the lens doesn't influence the DOF in anyway but that only the difference in sensor size influence the DOF, simply to show that sensor size alone do have an impact on the DOF.
So the diffrence between the DOF between the two formats is just because the APS-C sensor is smaller then the 35mm and nothing more.
I do completely agree with you on the rest but not just the first part of your comment, or do you have another way to show the influence the COC has?
The quotations of the post came from here after all.
here is our conversation so far.
johnriley wrote:
This is a thing that's often misquoted, but smaller formats have more DOF for a given field of view and that's because the focal length of the lens to achieve that field of view is shorter.
An extreme example is that a Minox with its 15mm standard lens has such an immense FOV that it doesn't need to be focused even at f3.5, having DOF from 9 inches to infinity. The circle of confusion is minute to make a reasonable sized print.
A Rolleiflex TLR (6x6cm) uses an 80mm lens and has relatively little DOF by comaprison, but also has a larger circle of confusion as less emlargement is needed.
So an APS-C DSLR will have more DOF than a full frame one. We know this is true - look how difficult it is to get an out of focus background with a compact digital camera with its tiny sensor.
This is a thing that's often misquoted, but smaller formats have more DOF for a given field of view and that's because the focal length of the lens to achieve that field of view is shorter.
An extreme example is that a Minox with its 15mm standard lens has such an immense FOV that it doesn't need to be focused even at f3.5, having DOF from 9 inches to infinity. The circle of confusion is minute to make a reasonable sized print.
A Rolleiflex TLR (6x6cm) uses an 80mm lens and has relatively little DOF by comaprison, but also has a larger circle of confusion as less emlargement is needed.
So an APS-C DSLR will have more DOF than a full frame one. We know this is true - look how difficult it is to get an out of focus background with a compact digital camera with its tiny sensor.
Anvh wrote:
Did a comparison with the FA*85 and the DA*55.
The DA*55 can be seen as a digital replacement of the FA*85 on 35mm format. He is a part of that comparison.
almost 40cm.
Good the photos would be very different but still it has some effect on the DOF and I'm quite glad of that.
johnriley wrote:
This is a thing that's often misquoted, but smaller formats have more DOF for a given field of view and that's because the focal length of the lens to achieve that field of view is shorter.
Ah yes didn't though about that stupid me This is a thing that's often misquoted, but smaller formats have more DOF for a given field of view and that's because the focal length of the lens to achieve that field of view is shorter.
Did a comparison with the FA*85 and the DA*55.
The DA*55 can be seen as a digital replacement of the FA*85 on 35mm format. He is a part of that comparison.
Quote:
The FA* 85mm on a 35mm camera and the DA* 55mm on a Pentax K10D.
Because the 55mm doesn't give the same angle of view as the FA* 85mm, we need to stand just a bit closer. The subject distance for the FA* 85mm is 10m and for the DA* 55mm 9.9m, with these distance the subject will be the same length on both photos.
With the distance given above and both wide open f/1.4 the;
DA* 55mm would have a DOF of 183.8 cm on the K10D
FA* 85mm would have a DOF of 116.8 cm on 35mm film
About the circle of confusion.The FA* 85mm on a 35mm camera and the DA* 55mm on a Pentax K10D.
Because the 55mm doesn't give the same angle of view as the FA* 85mm, we need to stand just a bit closer. The subject distance for the FA* 85mm is 10m and for the DA* 55mm 9.9m, with these distance the subject will be the same length on both photos.
With the distance given above and both wide open f/1.4 the;
DA* 55mm would have a DOF of 183.8 cm on the K10D
FA* 85mm would have a DOF of 116.8 cm on 35mm film
Quote:
Now we are going to look purely on what the sensor size does for the DOF so the FA* 85mm on the pentax K10D and on 35mm film with a focus on a subject 10m away and both wide open;
Pentax K10D would give you a DOF of 77.7 cm
35mm camera would be a DOF of 116.8 cm
So the circle of confusion. still makes a significant difference of Now we are going to look purely on what the sensor size does for the DOF so the FA* 85mm on the pentax K10D and on 35mm film with a focus on a subject 10m away and both wide open;
Pentax K10D would give you a DOF of 77.7 cm
35mm camera would be a DOF of 116.8 cm
almost 40cm.
Good the photos would be very different but still it has some effect on the DOF and I'm quite glad of that.
johnriley wrote:
It's not the circle of confusion that causes your second observation, but the difference in magnification. They are different images so it doesn't have a relevance to DOF in the context of differences through format.
It's not the circle of confusion that causes your second observation, but the difference in magnification. They are different images so it doesn't have a relevance to DOF in the context of differences through format.
Anvh wrote:
John my last observation was with the FA*85 only on both formats at the same focus distance of 10m so the lens was acting the same for both cameras so only the senor/film size makes a difference.
If you mean that the APS-C needs to be magnified more then the 35mm to cover a standard 6"x7" photo then you're correct and that's what the circle of confusion is about... at least for the most part.
Since the 35mm isn't magnified that much you have more leeway before something appears not sharp.
At least that's my understanding of it.
John my last observation was with the FA*85 only on both formats at the same focus distance of 10m so the lens was acting the same for both cameras so only the senor/film size makes a difference.
If you mean that the APS-C needs to be magnified more then the 35mm to cover a standard 6"x7" photo then you're correct and that's what the circle of confusion is about... at least for the most part.
Since the 35mm isn't magnified that much you have more leeway before something appears not sharp.
At least that's my understanding of it.
johnriley wrote:
The circle of confusion is a useful design objective, but as we can define what we want it to be, so it isn't a constant value. It's a convention. When using a DOF scale or table I might take the DOF at f8, focus accordingly, but I would set the stop at f11. This is so the quality level is more critical and bigger prints can be satisfactorily made.
Some manufacturers are more accurate than others when defining their DOF scales and tables, and some more generous with their expectations, it depends how you look at it.
Don't forget that in an ultimate sense there is no DOF. The only sharp point in an image is the plane you are focused on.
Let's pick it up from that point on.Quote:
John my last observation was with the FA*85 only on both formats at the same focus distance of 10m so the lens was acting the same for both cameras so only the senor/film size makes a difference.
When you do this, the lens has a field of view similar to a 127.5mm lens on the 35mm camera, so you are not comparing like with like. We would expect a 127.5mm lens to have less DOF, but of course the relevance here is not actually the focal length but the magnification.John my last observation was with the FA*85 only on both formats at the same focus distance of 10m so the lens was acting the same for both cameras so only the senor/film size makes a difference.
The circle of confusion is a useful design objective, but as we can define what we want it to be, so it isn't a constant value. It's a convention. When using a DOF scale or table I might take the DOF at f8, focus accordingly, but I would set the stop at f11. This is so the quality level is more critical and bigger prints can be satisfactorily made.
Some manufacturers are more accurate than others when defining their DOF scales and tables, and some more generous with their expectations, it depends how you look at it.
Don't forget that in an ultimate sense there is no DOF. The only sharp point in an image is the plane you are focused on.
I chose the same lens setup (FA*85 at 10mm focus for both cameras) so that the lens doesn't influence the DOF in anyway but that only the difference in sensor size influence the DOF, simply to show that sensor size alone do have an impact on the DOF.
So the diffrence between the DOF between the two formats is just because the APS-C sensor is smaller then the 35mm and nothing more.
I do completely agree with you on the rest but not just the first part of your comment, or do you have another way to show the influence the COC has?
Comment by Anvh posted on The impact the sensor size has on the lens at 15/07/2009 - 18:03
