fgianni
Trainee Amateur
I'll spare you the maths, which is based on the fact that an APS sized sensor has a smaller COC than 35mm film, and has already been posted here a year ago or so, but the result is that for a crop factor of 1.5 you get the depth of field of a lens roughly 1.22 times longer.
So for a 50mm on an sensor with a 1.5 crop factor you will have the field of view of a 75mm lens on full frame 35mm (50 * 1.5) and the DOF of a 61mm lens on full frame 35mm (50 * 1.22)
So for a 50mm on an sensor with a 1.5 crop factor you will have the field of view of a 75mm lens on full frame 35mm (50 * 1.5) and the DOF of a 61mm lens on full frame 35mm (50 * 1.22)
anaanda
Well-known
Thanks for all the answers, judging from what everyone has said it seems like I will get enough bokeh to be satisfied. Maybe it won't be exactly the same as the sensor is smaller, so it seems my bokeh will be similar to a 75mm lens instead of a 50..
jaapv
RFF Sponsoring Member.
anaanda said:
Far be it form me to cross-post, but I did post a list of DOF's for the M8 and RD1 in the appropriate forum.
rvaubel
Well-known
There is a complete difference of opinion. I had no idea that some people thought that pointnshoots and view cameras had the same DOF. This is not a subtle difference of opinion. I have not engaged in any of the technical arguments because if you don't agree that tiny sensor sized cameras have larger depth of fields than large format cameras, we are not even on the same page.
Rex
Rex
manojd
Established
This is interesting. Try loading your 4x5 with a 35mm film and take a shot of the same subject. If you compare the shot with 4x5, it will have a wider DOF because the 35mm frame is within the circle of confusion.
rvaubel said:
saxshooter
Well-known
anaanda said:
You will be satisfied. I am with my 50 summicron and R-D1. Now, if you can get your hands on a Megaperls 1.3N viewfinder magnifier, you'll be even happier.
fgianni
Trainee Amateur
rvaubel said:
Your statement is correct only if you apply exactly the same enlargement to both the picture taken by the viewcamera and the picture taken by the 1/8" sensor, but as soon as one of the two is enlarged more (which is always the case), then the circles of confusion become different and this affects the depth of field.
rvaubel
Well-known
manojd said:
Try loading your 4x5 with a "normal" lens and compare it with a 35mm with a "normal" lens. shoot the same subject at the same distance with the same background and the same aperture. In other words, don't move, just take a picture with one camera and then the other. Now make an 8x10 print and look at each of then at the same distance. Now, which one has the the greater depth of field?
If anyone says, "it depends" I'm going to kill myself
Rex
starting to foam at the mouth
rxmd
May contain traces of nut
I guess if you engaged in the technical argument instead if closing your eyes to it because it seemingly says something unfamiliar, you would come to realize that we are on the same page after all. I use medium format every day, you can believe me that I know about how prints look different.rvaubel said:
Philipp
RichC
Well-known
See my post from a few months back (also, youcan download a Word file of DOF charts for common lens focal lengths):
http://www.rangefinderforum.com/forums/showthread.php?p=241964#post241964
http://www.rangefinderforum.com/forums/showthread.php?p=241964#post241964
rvaubel
Well-known
rxmd said:
Yes, but do you agree that smaller sensor cameras have bigger DOFs?
YES or NO ? Just a simple answer
What'so matter....... you're chicken?
Eyes closed until someone finally fesses up
Rex
not holding my breath
saxshooter
Well-known
rvaubel said:
This is not at all the point that I was making. You are talking two different cameras (4x5 vs. 35mm), two different lenses (although they are considered "normal'), and then making the same size print as the result to judge from -- of course you will get vastly different results -- for many different reasons.
How about this for an unwieldy experiment: Take two Leica M6 cameras and two 50mm summicron lenses. Shoot one body as normal ("full frame", if you'd like), and on the other body, somehow mask the film gate so that you are only exposing an APS-sized area of your film. Put them both on a tripod, aim it at a target, shoot both wide open at the same exposure.
Now, it is safe to assume that the APS-masked M6 body will yield exposures that doesn't have its edges exposed. The other M6 full frame body will give you fully exposed frames. But WITHOUT ENLARGING THE IMAGES (because if you do, you are throwing in a whole other set of variables and of course 8x10 prints from each camera will look different) how is the depth of focus and bokeh different between the two frames?
Yes I agree that if you were to make the same size 8x10 print from each of the abovementioned setups, you will get visibly different results in field of view, perceived DOF, etc. etc.
But to echo the answer I gave to the original question, you will maintain the characteristic of the lens. Again, my earlier example: Putting a 14mm rectilinear lens in front of an APS-sized CCD will give you a field of view crop of 21mm. But what is happening optically in the center of that field of view crop of 21mm will exhibit the characteristics of the 14 -- much more exaggerated distortion characteristic than a 21mm lens. Ever put a 15mm fisheye on a camera with an APS sized sensor? Your FOV crop may be 23mm, but it still has the fisheye lens characteristics. You are just losing the edges.
OK I'm done.
rvaubel
Well-known
saxshooter said:
Much to my dismay, I can't find one thing to disagree with
I must have misunderstood
Sorry
Rex
Afr, Arf!!
pfogle
Well-known
I don't get this bit about distortion - if you are using a rectiliear lens (fisheyes are a different story) then the only distortion is from the geometry of the projection onto the image plane - and that's identical for 14mm on APS-C and for 21mm on full frame - similar triangles anybody?saxshooter said:
Am I missing something?
jonasv
has no mustache
pfogle said:
You are correct, in theory. A lot of lenses do have some kind of distortion though (barrel or pincushion), visible at the edges. This is minimal on prime lenses, but not non-existant.
saxshooter
Well-known
Re 14mm, distortion may have been a poor choice of words.
At any given focus distance OPTICALLY a 14mm has more depth of focus than a 21mm lens. So what I am saying that when you have the 14mm on an APS sized sensor camera, what you are getting (in terms of depth of focus) in the center of your frame will still be what you would with a 14mm lens, and NOT what you would get with a 21mm lens (although that is your "cropped" view).
The lens has not changed. The center portion of your image hasn't changed.
I am not talking enlargements and then comparisons of those enlargements here. If you are looking through a 14mm lens, regardless of full frame or masked out/cropped out APS frame, you are still looking through a 14mm lens, and what is happening in the center of your frame in terms of depth of focus (or how far back an image is "thrown back" from you as what happens with wide angle lenses, as I used to describe it a years ago, not very academic) is still very much a 14mm lens. NOT like what you would see looking through a 21mm lens.
Take a toilet paper tube and look through it with one eye closed. Did your eye change? Did your depth of focus change? No. Your eyes are just seeing less peripherally.
** Sound of toilet flushing **
OK, now I am really done.
At any given focus distance OPTICALLY a 14mm has more depth of focus than a 21mm lens. So what I am saying that when you have the 14mm on an APS sized sensor camera, what you are getting (in terms of depth of focus) in the center of your frame will still be what you would with a 14mm lens, and NOT what you would get with a 21mm lens (although that is your "cropped" view).
The lens has not changed. The center portion of your image hasn't changed.
I am not talking enlargements and then comparisons of those enlargements here. If you are looking through a 14mm lens, regardless of full frame or masked out/cropped out APS frame, you are still looking through a 14mm lens, and what is happening in the center of your frame in terms of depth of focus (or how far back an image is "thrown back" from you as what happens with wide angle lenses, as I used to describe it a years ago, not very academic) is still very much a 14mm lens. NOT like what you would see looking through a 21mm lens.
Take a toilet paper tube and look through it with one eye closed. Did your eye change? Did your depth of focus change? No. Your eyes are just seeing less peripherally.
** Sound of toilet flushing **
OK, now I am really done.
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Sparrow
Veteran
pfogle said:
In the case of both rectilinear and fisheye lenses of the same length the distortion must be the same, both are projecting a 3D reality onto a 2D plane so both must distort that reality by the same amount
Just to add to the circle of confusion
sorry
jaapv
RFF Sponsoring Member.
saxshooter said:
Most of the distortion is in the outer zones and edges : coneheads and the like. So cropping down an extreme WA DOES help against distortion. As for the perspective, which is sometimes erronously called "distortion" too, this is dependent on crop as. a 50 mm crop out of a 15 mm shot will show exactly the same perspective as a 50 mm taken from the same standpoint. In other words: perspective is solely dependent on the relative position of the subject and the film, not on the lens used. Interestingly enough, perspective is also subjectively dependent on the viewing distance related to the print size. A small 6x9 cm. print will show the ideal "natural" perspective when viewed from the normal distance - using a 90 mm lens, not a 50 mm. So it is dependent on the position of the final receptor - he human eye- as well.
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pfogle
Well-known
well, this thread has opened up a lot of areas of confusion (not just circlesjaapv said:
) so here's a tiny bit from me...distortion - to me that only covers the change of geometry of an object ie straight lines -> curves (as in barrel or pincushion) and circles -> ellipses as in edges of wideangles (the so-called cosine distortion caused by the fact that the light is no longer perpendicular to the image plane). Converging verticals etc are perspective effects and not distortion.
perspective - depends on the relationship between the lens and the subject. I can't see an easy way to incorporate the eye (viewer) into this. In general, though, I think it's fair to say that a 'natural' perspective is any one where the final image (print, projection, etc) covers the same angular view at the eye as the original scene did at the lens. Otherwise, I suspect it's a meaningless term. Clearly, this has nothing to do with the focal length of the lens per se, but does seem to, as a print is rarely viewed from the appropriate distance (ie, for a superwide on 11x14 paper, you'd have to have your nose about 2 inches from the print!)
Sorry to pitch in, but couldn't help myself
Sparrow
Veteran
Except and just to make it worse the human FOV is more than 130° equivalent to a 10mm on 135 not 40 or 50mm that its perceived to be