View Full Version : Shallow Depth of Field without adapter?
Pasha Hanover January 14th, 2009, 04:02 PM I asked a similar question in the HVR-Z7U section, however, as I am still trying to figure out what camera I want to get, so I had a similar question for the EX1 and EX3.
When it came to the Sony HVR-Z7U, I am told you still needed a Letus35 Extreme to get the depth of field effect. Does this also hold true to the EX1 and EX3? I ask because these cameras have bigger CMOS chips than the HVR-Z7U. Since the EX3 has interchangable lens capability (like the Z7U) but as it does have bigger CMOS chips, is the Letus35 Extreme really required or can you just use a regular adapter to connect a DSLR lens and get the depth of field effect?
Thanks.
Bill Ravens January 14th, 2009, 04:17 PM DOF is related to something called the Circle of Confusion. Without getting really technical, the image size at the focal plane is critically important. With a 1/2 inch sensor, the DOF of the EX1/EX3 is noticeably shallower than the 1/3 inch sensor of more conventional CCD's, but, not as shallow as a 35mm focal plane. Unfortunately, use of a 35mm lens will not decrease the DOF unless the image size at the focal plane is also increased. In other words, no, you can't get the same DOF with a 35mm lens without the use of a Letus-like adapter on the EX1/EX3.
Pasha Hanover January 14th, 2009, 04:31 PM Excellent, thank you. I guess I'll have to budget in another $1500 for a Letus35/Brevis35 adapter then, haha.
Just to take the topic in a different path. Why get the EX3 when you can use an EX1 and just use Letus35/Brevis35 adapter and as you explained get even better results?
Peter Wright January 14th, 2009, 06:03 PM You can reduce depth of field on practically any camera, by moving the camera away and zooming back in. Lighting and aperture can also be utilsed to increase the effect. The "amount" of shallowness will not be as dramatic as with an Adapter such as Letus, but the basic EX1 with its 1/2" sensors can achieve it quite strongly.
Personally I like to use the effect very sparingly. So many feature movies overdo it - I have watched one or two recently where I was sitting there silently screaming "I want to see the background, not a constant blur!"
Bill Ravens January 14th, 2009, 06:58 PM As far as I'm concerned, the difference between a studio movie and an indie is the aesthetic content. There is no question that skill is a very big part of the esoteric beauty, the ability to make the moving images seamless, such that the viewer is one with the images. One of the most subtle ways the DP/Director can manipulate the audience without interrupting the zen of the moment, is thru selective focus, aka pull focus. It is not a minor effect. In fact, in skilled hands, it's the single most important variable, in close competition with proper lighting. The single biggest failing of anything less than super 16mm is DOF. The EX1/EX3 both have a 1/2 inch sensor. Leaps and bounds better than a 1/3 inch sensor, but, still not super 16.
Noah Kadner January 15th, 2009, 12:21 AM Actually I've seen some incredibly poorly shot studio movies that would contradict that aesthetic argument. Studio movies generally have the stars and the budget for locations- that what sets them apart more than anything. Spend some time flying commercial long-haul flights that show movies and you'll see the sort of studio dreck I'm referring to. Aesthetics alone are just a part.
But anyways- to get back to the original question yeah you need an adapter. :)
-Noah
Michael Palmer January 15th, 2009, 12:49 AM Why get the EX3 when you can use an EX1 and just use Letus35/Brevis35 adapter and as you explained get even better results?
Well the viewfinder is amazing on the EX3 and Cinevate has my attention right now as they have dealt with the stock EX lens with a custom CINEFUSE to help with the edge to edge focus issue that all the other adapter companies are struggling with, and they will be marketing a rely lens for the EX3 in the spring that works with the existing Brevis MP35 adapter. By the time you get all of the pieces to this rig it will be about $2500 and it is money well spent that has a strong resell value right now.
Michael Palmer
Jay Gladwell January 15th, 2009, 05:54 AM Personally I like to use the effect very sparingly. So many feature movies overdo it - I have watched one or two recently where I was sitting there silently screaming "I want to see the background, not a constant blur!"
Peter, I couldn't agree with you more. Whatever happened to "moderation in all things"?
I came into cinematography back in the early 70s. I can't tell you how many cinematographers broke their backs to achieve deep focus or a deeper depth of field. They and the directer wanted the audience to see deeper into the frame!
I think a lot of this can be blamed on the zoom lens. Back in the day, before I came into the business, they were, by and large, using prime lenses. Seldom was a zoom or telephoto lens used in a motion picture. As I reacall the zooms really came into being back in the 60s. And, as with most things, it was over used, especially in TV shows. The excuse being it was quicker to zoom than set up a dolly and track. In my opinion, the trucking shot (dolly in) is far more elegant than a zoom--it's a whole different animal!
Don't get me wrong, I'm not saying zoom shots are bad. They have their place, in moderation, as with most things.
Benjamin Eckstein January 15th, 2009, 06:40 AM The original question has been answered correctly, but you certainly CAN achieve shallow focus without an adapter. There are plenty of sample videos online (I have posted a few) that show the range of focus you can get without an adapter. I use adapters sometimes, and while they are nice, they have some limited functionality and can be fussy. I think the EX-1/3 take beautiful pictures without any accouterments and as new camera makers start to introduce bigger chips in their cameras, the 35mm adapter will be a thing of the past. But yes, to achieve 35mm DOF (given same camera position, field of view, etc.) you will need an adapter, but just be aware of their limitations (like the ability to achieve deeper focus which becomes a real pain sometimes when shooting scenes with groups of people).
BE
Pasha Hanover January 15th, 2009, 10:22 AM Thanks for all the answers. Speaking of adapters. Anyone familiar with the Redrock Micro adapters? Any thoughts on quality and compatability with the EX1?
Michael Palmer January 15th, 2009, 11:13 AM I purchased the M-2 Red Rock Micro complete system at NAB 2008 and it was terrible, the image quality was horrible and I found out later that the person selling me this thing knew it didn't work with the stock EX lens and he knew about the issues. I worked with him for over 2 months and he ended up blowing me off and I told him I wouldn't hesitate to tell anyone about this ordeal. I won't recommend this product to anyone. And at the time they had very little support.
Michael Palmer
Pasha Hanover January 15th, 2009, 01:06 PM That's good to know cause I was thinking of getting it for my Sony A1 for now and then using it for the EX1 when I get that later this year. When you say it doesn't work, it just looks bad or doesn't work at all. Do they have some sort of fix for it or adapter now?
Charles Papert January 15th, 2009, 02:14 PM Thanks for all the answers. Speaking of adapters. Anyone familiar with the Redrock Micro adapters? Any thoughts on quality and compatability with the EX1?
Redrock Micro: Create the Cinema Experience (http://www.redrockmicro.com/)
I shot a short film with this combo and it worked fine, except for a bit of vignetting on certain shots which I was able to correct out.
tablemanners (http://web.mac.com/chupap/Films/tablemanners.html)
Pasha Hanover January 15th, 2009, 03:58 PM That brings some hope back to this adapter, haha. So we have one thumbs up and one thumbs down. Anyone else have comments about the Redrock micro?
Bill Ravens January 15th, 2009, 04:05 PM Phil Bloom did a review of several adapters, including the Letus, Redrock Micro, and Brevis. His conclusion was that the Letus was the best of those he reviewed. I, also, own the Letus Extreme. While it works as advertised, it has many shortcomings, not the least of which is weight. All adapters are cumbersome and unwieldly. Letus improved their design with the Ultimate.
Michael Palmer January 15th, 2009, 04:07 PM Pasha
If they had a fix by now I wouldn't care as this company treated me like dirt.
The image quality was completely unacceptable.
I did rent this m-2 once for my V1U and it was acceptable for that camera, however it took some time to fine tune it to the camera. I spent countless hours trying to adjust it for the EX1 and I was finally told it just won't get any better by RRM.
Pasha Hanover January 15th, 2009, 04:34 PM That's unfortunate about their customer service. The impression I got from their site is that they cater and want to help the "indie". I was planning on buying a full system with mattebox, rails and all and all from them. I don't want to flush $2500 down the toilet if it ends up looking bad and with no support from them to try and fix it. :-( So now I don't know...
Simon Wyndham January 15th, 2009, 04:49 PM Why keep trying for short depth of field? Films in days gone by strived for deep depth of field. Watch films such as Lawrence of Arabia for example. In fact even more modern films such as Terminator 2 aimed for a long depth of field.
Use your tools and make them work for you.
On a technical level zooming in does *not* reduce depth of field. Depth of field is purely the result of iris setting and sensor size. All zooming in does is show you the differential in focus that is in the picture anyway, but that the resolution of the picture cannot show/discern when it is fully wide.
Bill Ravens January 15th, 2009, 07:34 PM All zooming in does is show you the differential in focus that is in the picture anyway, but that the resolution of the picture cannot show/discern when it is fully wide.
I would disagree. The DOF is determined by the subject distance (that is, the distance to the plane that is perfectly in focus), the lens focal length, and the lens f-number (relative aperture). Hence, shallowness of focus is directly related to the focal length(or zoom ratio). This is well known optical physics.
Simon Wyndham January 15th, 2009, 07:51 PM Hence, shallowness of focus is directly related to the focal length(or zoom ratio). This is well known optical physics.
No, focal length will only show you the effects of the f-stop setting and sensor size. You cannot change depth of field from a straight up technical standpoint by increasing focal length.
Chris Leong January 15th, 2009, 09:53 PM Hi All
I just finished principal photography on my short dramatic film "5150". I had a skeleton crew and three excellent, professional actors for half a day.
So even though I own a Letus Elite and the whole complement of stills lenses, I elected to shoot the piece without a DOF adaptor.
You can see the first, untimed rough cut of the piece here:
Director's Sample - "5150" - Rough Cut By Chris Ross Leong On ExposureRoom (http://exposureroom.com/5150)
I do have a fine cut, timed, colored and film effected, and it will go up onto exposureroom when the site is back online (they're upgrading the site now).
You can see that I've staged a lot of the headshots with deep backgrounds to direct the viewer's eye accordingly, and not many people can tell if I used a DOF adaptor or not.
I'd say that the DOF adaptor works much better indoors or in situations where there isn't a lot of depth in the subject matter (i.e. not a lot of distance between the subject and the background) - the video-ness of the camera shows up much more in a shallow shot.
Mainly the reason to leave the Letus behind was that I didn't have a pro focus puller on board and I had to concentrate on the direction of the piece. Also, my camera operator was new to the EX1 and so had to struggle to master that, his hands were already full trying to deal with the lens in manual focus while hand holding.
Second, we were going with existing light in a very short winter's day. So there was a lot of fiddling with camera settings to get the entire piece shot at a consistent T stop, T3. If I had the Letus/ZF setup with me, that would have meant a bunch of ND 4x56's flying in and out of the matte box each shot. Doable with a pro camera crew, or even a semi-trained crew. I had neither for this shoot.
Finally, we were shooting in a bad part of town. I didn't have any extra bodies to watch the equipment cases while we were shooting, and no way was I going to risk my prime lens case out there alone in the back of a car.
FYI, we got 105 shots off in the 4 hour shoot, around 80 were usable, and 65 of those are in the rough cut.
On topic, I've been in on the DOF deal from the very beginnings here in the DIY section, have built my own, have owned or operated nearly all of them at one time or another, settled on one of the first Extremes, now have the Elite BF adaptor on it. I'm sure others work, just not as well, IMO. But, as has been mentioned above, it's a real package to handle alone, especially with 12 lenses and a matte box, and quick release adaptors to go off and on tripods, etc. I'd say it needed a lot more handling than, say my Aaton S16 camera.
HTH
Cheers
Chris
Bill Ravens January 15th, 2009, 10:06 PM I stand corrected. However, I will say that the apparent DOF changes. In the end of things, when the viewer sees the images, selective attention is placed on the plane of highest apparent focus. So, technical myth or not, higher zoom ratios appear to decrease the DOF. And the intent of manipulating the plane of attention is achieved.
Brooks Graham January 15th, 2009, 11:08 PM I stand corrected. However, I will say that the apparent DOF changes. In the end of things, when the viewer sees the images, selective attention is placed on the plane of highest apparent focus. So, technical myth or not, higher zoom ratios appear to decrease the DOF. And the intent of manipulating the plane of attention is achieved.
Hmmm. Interesting topic as I did a simple test a couple of days ago to record the apparent DoF changes at different lengths on the EX3 as compared with an FX1. The link below is a QT of the EX3 on a DSC backfocus chart placed 10 feet from the camera and another five feet behind it. Started at Z99 backing off slowly with pauses at Z75, Z50, and Z25. It really looks like DoF changes to me. Apparently.
Oh, and yes it was shot outdoors in the frigid winter weather... ;-)
http://idisk.mac.com/brooksgraham-Public/BDGA0059_01-H.264-25pct.mov
Thoughts?
Brooks Graham January 15th, 2009, 11:45 PM I did the same experiment as the author of the article cited in a previous post, isolating parts of the image, and it's more than just an apparent illusion. This looks exactly like a changing DoF to me.
And to be clear: the f-stop was held constant as was the sensor size
Peter Wright January 16th, 2009, 12:47 AM Yes, I must admit, I was interested but not totally convinced by Walter Graf's article - firstly, if the background is perceived as softer, it IS softer as far as I'm concerned, and in the part where he posted two close ups of a blue ball on a shelf behind the subject to show they were the same - to my eyes the right hand one is clearly softer.
Bill Ravens January 16th, 2009, 07:01 AM I agree with you guys, however, I think the point Simon was wanting to make is that zoom/tele lenses don't, TECHNICALLY speaking, create a more shallow DOF. It only looks like it. DOF is a very specific phenomenon in the physics of optics that can be calculated. Using a higher zoom factor with the math that describes DOF, will not show a change in DOf
And my point is, that's good enough for me to use a zoom/tele for shallow DOF, if appropriate for the scene.
Ted OMalley January 16th, 2009, 07:43 AM Hmmm. Okay. So, then, perhaps what Simon is saying is not contradictory to the following statements:
1. If you are after a very shallow depth of field look as can be achieved with 35mm cameras but without a 35mm adapter, zoom can be a very useful tool (if you have the space).
2. Zoom, in conjunction with Iris, can provide a final product in which the background and foreground focal planes are quite far apart - much more than using Iris alone.
3. Shooting full wide will expand the focal plane to such a degree that even when shooting with the Iris fully open, separation between foreground and background is minimal.
4. The camera's Depth of Field indicator (accessible by the Lens Info button, by default) displays a scale in either feet or meters. At full Iris (1.9) and with the lens fully wide (5.8), the focal plane indicator is wide enough to cover the entire scale (1 to infinity). Zoomed only to 10, the indicator is reduced to 1.5 meters. At 15, the indicator covers only a half a meter. Between 25 and 81.2, the indicator is even smaller and reduces in size, but to such an extent that it is difficult to attach a number to it based on eyeballing the scale.
5. While zoomed, I can shoot "through" a chain link fence in such a way that the fence is all but invisible. At full wide, without changing any other settings, that fence might be out of focus, but appears solid. It appears to me that there is more going on than simply a "differential in focus that is in the picture anyway, but that the resolution of the picture cannot show/discern..."
It is my opinion that zooming does affect the DoF. I might be wrong, but actual testing this morning has me convinced otherwise.
Bill Ravens January 16th, 2009, 07:54 AM One thing to remember is that most zooms change the effective aperture(by a small amount) when you change zoom settings. This effect has to be accounted as aperture change, not zoom change.
Simon Wyndham January 16th, 2009, 08:15 AM Hmmm. Okay. So, then, perhaps what Simon is saying is not contradictory to the following statements:
1. If you are after a very shallow depth of field look as can be achieved with 35mm cameras but without a 35mm adapter, zoom can be a very useful tool (if you have the space).
Yes, it can help. What I was saying was that zoom doesn't actually change the depth of field, however it does enhance the 'effect' of it because you are effectively enlarging the background, which if not technically in focus in the first place will look even more blurred when you zoom in.
2. Zoom, in conjunction with Iris, can provide a final product in which the background and foreground focal planes are quite far apart - much more than using Iris alone.
Remember that when you zoom all you are doing is enlarging the background, which is out of focus anyway even though you can't see it fully wide. The trouble with zooming is that you actually make the background appear closer to your subject effectively 'compressing' the distance between them. So overuse of the technique can make things a bit claustrophobic. Iris creates the DOF, zoom just amplifies the effect.
3. Shooting full wide will expand the focal plane to such a degree that even when shooting with the Iris fully open, separation between foreground and background is minimal.
I think this is more to do with resolution. If you are fully wide (depending on the lens of course) the background could still appear soft if your iris is fully open and your recording system and display was of high enough resolution.
If you zoom in to focus on an actor in, say, a forest location, or a beach, so that your background is out of focus and the actor is in focus, then you zoom back out to fully wide, your background is still out of focus even though you cannot see the effect due to the limits of resolution. What you are now seeing on the monitor is like taking a soft out of focus photograph and reducing it to a small size in Photoshop. Because the picture is now not of very high resolution it looks perfectly okay, even though in reality we know the picture is not sharp.
"differential in focus that is in the picture anyway, but that the resolution of the picture cannot show/discern..."
Exactly.
It is my opinion that zooming does affect the DoF.
There are no if's but's, why's or maybe's. The actual DOF is not affected. It is only an illusion of DOF.
Ted OMalley January 16th, 2009, 08:16 AM Bill,
I watched the Iris ring and the 1.9 in the viewfinder. Neither 'appear' to change. Are you saying that there is a "behind the scenes" change?
I would have to say that the highlights look slightly dimmer as I zoom in, is this the aperture change you are referring to, or some other optical effect?
If the aperture is secretly and 'unreportedly' closing as I zoom, accounting for the darkening highlights, then it would be increasing the depth of field, rather than reducing it. However, you seem to be indicating that the increased depth of field effect is actually assisted by the covertly changing iris.
Please elaborate.
Thanks,
Ted OMalley January 16th, 2009, 08:21 AM There are no if's but's, why's or maybe's. The actual DOF is not affected. It is only an illusion of DOF.
Great, now even more of my life is an illusion.
Next, someone will say that time is only an illusion (and teatime doubly so - Douglas Adams, paraphrased).
Ted OMalley January 16th, 2009, 08:30 AM Okay, I've decided that in the future, instead of making adjustments to obtain a shallow depth of field for a dramatic effect, I will instead make adjustments to create the illusion of a shallow depth of field.
If I'm only after a visual effect, who cares if it's real or fake?
Plus, since it sounds almost magical, I should be able to charge more for it, right? I'll call it the optical illusion surcharge.
Jay Gladwell January 16th, 2009, 08:33 AM Great, now even more of my life is an illusion.
Next, someone will say that time is only an illusion (and teatime doubly so - Douglas Adams, paraphrased).
Right, Ted! Don't you just love esotericism?
Michael B. McGee January 16th, 2009, 08:44 AM this may have already been mentioned. i didn't read every thread. has anyone tried using the macro mode to shallow the dof? i've played around with it and it appears to shallow the dof at close focusing at least. i haven't really tried it at say 10,15,20 feet. maybe i'll do that right now.
cheers.
Simon Wyndham January 16th, 2009, 08:52 AM Next, someone will say that time is only an illusion
It could be said that it is. For example my time may be different to your time. What is real time? We experience time in relation to other things in our world. Who is to say what standard time is. So time could be an illusion and a reality at the same time.
Simon Wyndham January 16th, 2009, 09:01 AM If I'm only after a visual effect, who cares if it's real or fake?
Because there is a difference. Witness one of the Steadicam shots in Ong Bak for example. the lens is wide. Yet they have focus differential and are able to pull focus. The shot has a lot of perspective in it, which isn't possible with a smaller sensor size and zooming in. Zooming in creates the illusion of depth of field, but it can never replace the DOF abilities of larger formats because zooming in compresses the distance between objects. In other words you lose the tool to be able to shoot wider and still have differential focus. Something that may or may not be desirable in a dramatic production.
Christopher Witz January 16th, 2009, 09:12 AM It could be said that it is. For example my time may be different to your time. What is real time? We experience time in relation to other things in our world. Who is to say what standard time is. So time could be an illusion and a reality at the same time.
" so... if your here, and I'm here.... isn't it our time?" Jeff Spicoli - Fast times at Ridgemont High
Ted OMalley January 16th, 2009, 09:16 AM Because there is a difference. Witness one of the Steadicam shots in Ong Bak for example. the lens is wide. Yet they have focus differential and are able to pull focus. The shot has a lot of perspective in it, which isn't possible with a smaller sensor size and zooming in. Zooming in creates the illusion of depth of field, but it can never replace the DOF abilities of larger formats because zooming in compresses the distance between objects. In other words you lose the tool to be able to shoot wider and still have differential focus. Something that may or may not be desirable in a dramatic production.
But we are not referring to large format cameras. This topic is in regard to using the EX1/3 without an adapter. So, in order to increase a perceived depth of field, zoom is essential. Real or fake, it is a valuable tool that helps an EX1/3 user leverage the benefit of 1/2" sensors and gain less depth of field. ("gain less" is one of the more confusing phrases here - my humble apologies)
Ted OMalley January 16th, 2009, 09:17 AM " so... if your here, and I'm here.... isn't it our time?" Jeff Spicoli - Fast times at Ridgemont High
Nice one!!
Simon Wyndham January 16th, 2009, 09:33 AM it is a valuable tool that helps an EX1/3 user leverage the benefit of 1/2" sensors and gain less depth of field.
It can be. However I am not sure why people want to fight against the camera. As has been pointed out in days gone by the shallow DOF of 35mm film etc was considered a major problem, not a benefit.
There are better ways to get a cinematic look. Overall composition is one, lighting is another, camera movement is a biggie (I'd take a Steadicam over a Letus any day of the week if I was trying to make things look 'bigger' and larger budget), and also final grading.
IMHO these 35mm adaptors cause people to overuse the shallow DOF look. It isn't special any more because so many people are using it now. I also find that it doesn't make the production look like big cinema simply because big films selectively use DOF. They use it when it is needed, not when it isn't. Going back to Terminator 2, Cameron, as evidenced by his commentary, actively sought a long depth of field for it, even going so far as to compliment his DP for being able to achieve it in such lighting that was used in the film.
So in answer to the original thread topic "Shallow depth of field without adaptor", no you can't get as shallow a depth of field with a 1/2" camera as you can with a 35mm adaptor. Go to, say 100mm focal length with an EX and 100mm with an EX and a 35mm adaoptor, and the 35mm adaptor background will be far more out of focus than the EX even though they are at the same focal length. The EX cannot compete with it on any level. So why bother? The camera cannot achieve the same sort of shallow depth of field, so there is no need to fight it. You can certainly get a good effect when set up correctly, but to zoom into every shot just to get something OOF is silly.
Bill Ravens January 16th, 2009, 09:36 AM FWIW...
and this thread is degenerating....
no, there is no hidden aperture adjustment. It's just the way it works. When you zoom in, the effective aperture of the lens changes because there is a narrower field of view. The lens elements in a zoom lens move in relation to the lens iris. This has the effect of an iris diameter change. Look at some fine 35mm zoom lens specs. They quote the lens aperture as something like f/2.8-3.4. Or, point your camera at a blank single colored wall that is evenly lit. Make sure auto exposure is turned off and you're running on full manual(no auto-gain, no auto-shutter, no auto aperture)Now, zoom from one end to the other while watching your light meter. This means you get f/2.8 at wide and f/3.4 fully zoomed in. It's just the (black)magic of optical physics at work.
ya say ya wanna be a photogrfer, bunky? Better lern how them lenses work.
Jay Gladwell January 16th, 2009, 09:46 AM IMHO these 35mm adaptors cause people to overuse the shallow DOF look. It isn't special any more because so many people are using it now.
BINGO! Simon, you win!
Truth of the matter is, those whose insist that one must use shallow depth of field to make their little video look like a big movie, haven't watched too many big movies!
Christopher Witz January 16th, 2009, 10:23 AM It's in my opinion that there is a certain magic that happens when a photographers/cinematographers left and right brain hemispheres hit a sweet spot..... incredible content combined with the knowledge and knowhow of lighting and composition. Some folks can find themselves leaning to far to one side and in the end the the results are lacking. Obviously such thing as content can be subjective.... and most often a formula can not solve all.
I've noticed that most DP's tend to develop a style that is one or the other.... hyper-focal deep DOF or fast T stop shallow DOF.
I have to admit that if 2 different scenes are butted next to each other where one is SDOF and the other is DDOF is does not look like they go well together. Some sort of segway needs to connect them to make it work.
I find that the EX1 makes a fine camera for somewhat SDOF as long as it's not shot at the wide end of the zoom range.... and it's the wide end that I try to stay away from anyways since I just hate the barrel distortion. In fact, I often use the letus EX just so I can put something wider that is also distortion free.
Also.... from a personal perspective, coming from being a commercial still photographer for over 20 years using everything from 8X10 view cameras, Hassleblad etc... There ( with my eyes ) appears to be more of a 3Dish effect ( yes... even with deep DOF ) the larger the format.... as if the camera can look around the subject. I do notice this a little bit when using a letus.... and especially using the canon 5d2.
Tim Le January 16th, 2009, 10:23 AM Simon is right, but the catch is this is only true if the subject size remains the same. In these tests, this is done by backing up the camera (i.e. increasing the camera-to-subject distance). Here's another site that explains it: DOF2 (http://www.luminous-landscape.com/tutorials/dof2.shtml)
If the camera-to-subject distance remains the same, focal length absolutely does affect DOF. Looking at the DOF equation (Depth of field - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Depth_of_field)) you can see that it's affected by four variables: circle of confusion, aperture, subject distance and focal length. So for a given image format (which determines the circle of confusion), depth of field is determined by three factors: the focal length of the lens, the f-number of the lens opening (the aperture), and the camera-to-subject distance. If you keep any two of these three variables the same, then the third will affect DOF. This is not an illusion. This is what the math states.
Simon Wyndham January 16th, 2009, 10:31 AM Some sort of segway needs to connect them to make it work.
I agree, we definitely need more people on two wheeled gyroscopically balanced transports in videos.
Ted OMalley January 16th, 2009, 10:46 AM I agree, we definitely need more people on two wheeled gyroscopically balanced transports in videos.
That and a steadicam - nice combination!!
Bill Ravens January 16th, 2009, 10:47 AM I dislike pointilism. Therefore, all very fine paintbrushes should be thrown into the trash.
Who's to be the definitive judge of what's artistic and what isn't? Beauty is in the eye of...blahh...blah...blah. It seems very short sighted and closed minded to issue such blanket assassinations of technique.
And this is a pointless discussion.
Ted OMalley January 16th, 2009, 11:02 AM The camera cannot achieve the same sort of shallow depth of field, so there is no need to fight it. You can certainly get a good effect when set up correctly, but to zoom into every shot just to get something OOF is silly.
Simon,
I could not agree with this more. Completely agree with your points about the overuse of Shallow DOF and the misconception that it is "cinematic" just because the DOF is shallow.
That said, there have been a few times, outdoors is what comes to mind, where I really needed to minimize the DOF for aesthetic purposes. The background just looked better when you couldn't see the detail - wasn't an ideal background, but when out of focus it worked with the composition. I was using an HD100 at the time. FOR THAT SHOT I was able to mitigate the issue that shooting digital inherently has by zooming. With the EX1/3, it's even easier.
I certainly agree that to set up this way all of the time is at least arduous if not silly - that would feel like fighting with the camera. However, operators should not feel that they are doing something wrong just because they opted, in a shot, to decrease DOF for an effect.
If one is trying to gain a 35mm look or film adapter look in the EX cams, one won't be pleased. Conversely, compared to 1/3" cams, this camera naturally has a shallower DOF so the techniques for getting more separation from the background that have been used on 1/3" cams should work a little better with the EX cams.
Chris Hurd January 16th, 2009, 11:13 AM Good points, Ted... and it should be clearly understood that moving the camera back and zooming in will indeed decrease the apparent depth of field (it doesn't matter whether this is an "illusion" or not -- strictly speaking, *everything* you see on a television screen is an illusion, electronically derived -- all that matters is whether or not the background is out of focus, and the zoom-in technique, while only a work-around, definitely creates this effect... as we've all learned in Photography 101).
See The Ultimate Depth-of-Field Skinny by Jeff Donald (http://www.dvinfo.net/articles/optics/dofskinny.php) for more info.
Brooks Graham January 16th, 2009, 11:32 AM Then I propose new vocabulary.
Instead of Depth of Field, perhaps:
DoAS - Depth of Apparent Softness
DoANS - Depth of Apparent Non-Sharpness
C'mon guys, DoF is DoF and I'm sorry Simon, but the images I posted clearly show differing DoF which is no "illusion".
Also, my apologies for the thread hijack.
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