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Messages - Wild

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1
So here we go. Once that optical physics hits the sensor it's no longer optical, it's information. The sensor cannot capture the infinitely thin plane of focus made of sharp points. Instead, it captures everything between the two distances where "a circle" has the size of a pixel or smaller, so everything in that range is same sharp, because there can't be anything sharper than a pixel. At that level, enlarging the image isn't going to decrease the DoF, only soften it, because there is no hidden information.
How do we call THAT THING? The sharpest area between the two distances where "a circle" meets the pixel?

Hey Ecka, I was in a similar state of skepticism here for a while so I just want to help get you where I am now using some common sense.

Forget all the technical stuff about aperture and sensor size for a second and let's just think about this from a simpler perspective. Imagine we just took a picture of a friend. You look at the picture later at 100% on your 30" computer monitor and realize that you accidentally focused on their nose, so their eyes are slightly out of focus. Wouldn't you agree that the plane of focus is on the nose, but doesn't extend to the eyes? Yes of course.

Now let's imagine the friend we took the photo of wants to post that photo to Facebook, and so you post it and it becomes their new profile photo. The whole time you're thinking man that photo wasn't even in focus, but then you go onto their Facebook page, and voila, nobody can even tell if their eyes are in focus because the photo's so small. Basically, the photo looks great. Now I think we can agree that as far as we can tell, their profile picture is in focus. Which would mean that either:

A. You uploaded the wrong picture
B. Magic
C. Our DOF changed because we're now looking at a much smaller picture

And just in case you're not sure. It's obviously B.   ;D

2
Yes, the same area, as a percentage of the total image area. That is where your enlargement and viewing distance come in. Enlarge a point and it gets bigger and more obvious until it is a circle, but it stays the same size in relation to the image as a whole. CoC is just about setting a standard about the distance at which a sharp point becomes a blurred circle to a humans eye, you cannot take the human eye out of the equation because the very definition of DoF contains the words "acceptably sharp" or "beyond the resolution of the human eye". That is a subjective element that is generalised to 0.2mm at 25cm in the final output. Obviously if we stand back our eyesight becomes the limiting factor so we can increase the CoC.

Maintain a reproduction size and viewing distance ratio such that the CoC (point at which you can't see the difference between a point and a circle) and you can go as big, or as small, as you'd like.

Wow that makes soooo much more sense now. I don't know why it was so hard for me to grasp that DOF is a subjective quality of a photo, which is highly dependent upon the human eye. Thanks for taking the time to provide the great explanations and descriptions!

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Here is an example. I took this image for an artists show, it was printed to 46"x31". As a 700px web image most would agree the zip picture left, by her right cheek, is within acceptable focus, at f7.1 with a 100mm lens it is well within a dof calculators range. The second image is what that zip looks like when I printed it at 46" and viewed from the same distance. Clearly it is not now in acceptable focus. The only thing that has changed is the subject magnification. We have increased the CoC to such an extent that it no longer holds true, we can clearly differentiate between a point and a circle. To bring it back into acceptable focus we all we need to do is increase our viewing distance, step back from your monitor, across a room, and the zip will become sharp again.

Cool isn't it?  :)

Thanks for the example! Now that I've seen the example, I definitely understand where you're coming from.

Practically speaking, I know you're right about the depth of field being dependent upon print size, but from a mathematical perspective, isn't depth of field still the same?

In other words, if we were to define a specific "sharpness" level as a minimum threshold for being considered in focus, wouldn't the two images, no matter what size, have the same areas of the image being "in focus?" Without the limitations of our vision, technically the images have the same depth of field, even if we can't discern the difference, right? Please correct me if I'm way off here.

4
EOS-M / Re: Where is my backordered EOS-M w/22 STM lens?
« on: July 19, 2013, 04:06:08 AM »
Ordered on 7/9 as well (black body though) and I got the email tonight that it shipped. Should be seeing it sometime in the middle of next week.

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Also here, http://www.josephjamesphotography.com/equivalence/ for a very detailed insight into sensor sizes and their interaction with focal length, dof, aperture and iso. Yes, even iso has a crop factor!
Privatebydesign, thanks for the great link. Lots of fun explanations in there. However, I'm still not sure how print size and viewing distance affect DOF. Is there another explanation somewhere, or maybe some examples?

Btw, I've tried just resizing some of my photos on my monitor and seeing if they seem to have more/less DOF and can't really tell a difference...maybe I'm doing it wrong.

6
Depth of Field refers to the plane of focus within a photograph. A photo with a large depth of field might have much of the photo in focus, whereas a photo with a shallow depth of field might only have a few inches in focus.

The definition of "Depth of field" that you care about, is a collaboration between the sensor size, the focal length, and the aperture used to capture an image. Given the same focal length, with the same aperture, with the subject of focus the same distance away - a larger sensor will always have the shallower perceived depth of field. The actual depth of field is the same, but the narrower field of view caused by a smaller sensors' crop factor makes it seem as though the background is less blurred.

Put another way, if you were to frame a subject equally with a large sensor and a small sensor. The full frame would have to be much closer to the subject to have equal framing. Being closer to the subject causes the full frame's plane of focus to be shallower, therefore creating more blur in the background compared to the smaller sensor.

That's the key to the perceived depth of field advantage of full frame. Capturing a larger scene with a bigger sensor forces you to be closer to the subject to maintain the same framing as a small sensor, thereby shrinking the depth of field plane, and creating more background blur.

Everybody arguing about this seemingly simple, yet oddly complex question are forgetting that this started out as an innocent request for knowledge. We shouldn't be so quick to jump all over each others' cases - it only makes people hesitant to post thinking they'll be attacked with one misplaced word.


7
Wow, I was able to pick one up at the last minute. I was looking at the deals yesterday and thought the $299 price for just the M was a good deal...man am I glad I spend too much time on CR!

I'm excited because even if we upgrade if/when another EOS-M-model comes out in the near future, we'd be able to make back most of what we spent on the body while keeping the great lens.

And by the way, I think it's great that B&H won't charge you until it actually ships the product.

8
Animal Kingdom / Re: Your best animal shots!
« on: March 13, 2013, 04:20:41 AM »
Here's a few of mine  ;D

9
Landscape / Re: How Would You Edit This Landscape Photo?
« on: March 08, 2013, 08:40:13 PM »
Here's my attempt  8)

10
Lenses / Re: New EOS-M Lenses Soon [CR2]
« on: January 19, 2013, 02:51:14 AM »
I agree, they don't have to be large.... but the APS-C sized ones are even smaller, that means cheaper to make, and more likely to hit the mass market... If I were top take long term bets on Canon, I would say that the Rebel line morphs into the EOS-M line, and the APS-C mirrored cameras and APS-C lenses fall out of production.... leaving the FF lines at the top and the mirrorless as the enthusiast market.... but that's just my guess.

The EOS-M cameras are targeted at that enthusiast market. The lack of ability of that mount to cover a FF sensor indicates to me that Canon has no intentions of going FF mirrorless. Personally, I wish they had gone that route because now they are competing with the herd... FF would have allowed them to stand out in the mirrorless race.

As you can probably guess, I am conflicted on the issue. I can understand why they have done and why they have done it. I think it makes sense from a competition point of view, but it fails at taking a leadership role.


I'm right there with ya.  "Conflicted" is a really good way to put it  ;D

11
Lenses / Re: New EOS-M Lenses Soon [CR2]
« on: January 18, 2013, 11:09:24 PM »
Of course, this particular product could surely have been 'better', whatever that means. On the other hand so could ALL the other products in the market, so basically it's a meaningless statement. I just turned against the fact that there are people on this forum that never misses a chance to bash Canon for whatever reason. Whenever there is a launch of something they crawl out from their hiding places to complain about whatever features Canon has included in these products, or left out.

I'm not in a position to say what they should or shouldn't have done with the M. From what I understand it takes great pictures but its main shortcoming is the slow AF. It's plain ridiculous to compare it to 5000 dollar products.

I think Canon will address the what ifs in the future releases, maybe not to everybody's liking but building a new platform like they're doing here means that they have to start somewhere and to me it makes most sense to launch the volume product first. It'll be exciting to see what comes next.

I agree with you that Canon would have opportunities like basically no other player in the market to develop innovating products. I would argue that in a way they did that in 2012 though. Let's hope for an even more exciting 2013.

I agree that it's in Canon's best interest to release the volume product first.  I love the fact Canon finally joined the mirrorless world.  I don't even have a problem with the EOS-M (easy to say when you don't own it  :P)  My only gripe is now we're stuck with aps-c lenses.  If they made lenses that could cover a full-frame sensor, then eventually they could release a FF mirrorless and not have to restart with another new lens catalog.

Anyways, I'm with you in that they had a better 2012 than most people give them credit for. I think 2013 is going to be exciting too  ;D

12
Lenses / Re: New EOS-M Lenses Soon [CR2]
« on: January 18, 2013, 11:01:57 PM »
That's right.... bash Canon for trying to make an inexpensive compact camera and not using a full frame sensor....

Do you realize what using a full frame sensor means......  it means that you need full frame sized lenses... remember the silly looking picture of the EOS-M mounted onto the 800/5.6 just after it was released.. that's the direction you head with full frame sensors.... large and expensive.

Let's all sing the praises of the FF sensor. They are better than APS-C... that's a fact and not debateable... but why not continue this discussion on to it's logical conclusion and skip past medium format sensors and go straight to large format sensors.... a large format sensor could be made that would anahilate the specs of any FF sensor. Ok, the camera and lens(s) would be insanely large, heavy, and expensive, and only the photo elite could use it or afford it, but the pictures would be better.... I used to carry around a 8x10 with glass plates....did that mean that every other film camera was a piece of S___???? of course not! Same logic holds with sensor sizes.

The reason for APS-C (and smaller) sensors is to make cameras of a size and cost that will appeal to the masses. It is a cost and ergonomics thing at the expense of image quality. A lens that covers an APS-C circle is smaller, lighter, and less expensive to manufacture than a FF lens. The vast bulk of people will never understand why you would pay $500 for a lens.... and $5,000 for a lens is unthinkable. these are the same people that buy hundreds of rebels and point/shoots for every "pro" camera sold.... these are the people that are paying for the R/D to keep new inovations coming, these are the people that are paying to keep the lights on at the Canon factory.

Next time you want to start a rant about something, think before you type.....

I don't think you're directing the rant part at me, but just in case you were, I didn't mean to sound like I was ranting  :D 

Anyways, I disagree about the lens size.  Full-frame mirrorless lenses don't have to be large - just look at all the Leica lenses out there.  Those are full-frame lenses and plenty of them are puny (and still excellent).  Obviously there are some big ones too, so I'm not saying they can't be large. I just saying they don't have to be.  Even the RX1's 35mm is decently small, and apparently it's an excellent lens. 

13
Lenses / Re: New EOS-M Lenses Soon [CR2]
« on: January 18, 2013, 10:52:56 PM »
Canon could have easily churned out a mirrorless with a 5d mark ii-like sensor in it with a similar body style to the EOS-M, and kept it priced competitively.

Pricing a camera with a FF sensor competitively is pretty hard. Just look at the fixed lens Sony RX1 as a guide. :) Want a cheaper FF camera? You've already got the D600 and 6D.

Canon is in the business of money making. I'm sure their marketing staff must have done their homework and concluded APS-C is the way of the future. The sensors are cheaper to produce and the accompanying lenses are also smaller. Until manufacturers find a cheaper means to produce FF sensors, they'll always be reserved for a niche market.

I understand that full-frame isn't cheap.  I also realize aps-c is at a really good place price/performance-wise.  I just think that Canon could have easily leap-frogged the competition with a cheap-body full frame mirrorless (to help keep costs lower.

When Microsoft's Xbox came out back in 2006 (I think), it was as powerful as some $2000 gaming computers, and they sold it for $400.  They knew they were going to sell a lot of them, and the games that went along with it, so they kept the price low enough for it to take off.  A full-frame mirrorless, priced aggressively, and banking on lens sales to maintain larger profits, could do exceptionally well for Canon.  Seeing as they're probably the only company on this planet that could pull something like that off, it's disappointing to have them play it safe in the market with a smaller sensor, and remove a reason for them to make Full-frame mirrorless lenses.

I guess I'm in the minority, but I just think full-frame should be more readily available to the masses (I know somebody's going to say film is cheap).  If somebody told me each aps-c sensor costs 50 bucks to make, but a full-frame sensor costs like $1000, then I'm completely wrong and I take everything back  ;D

14
Lenses / Re: New EOS-M Lenses Soon [CR2]
« on: January 17, 2013, 05:03:19 AM »
Again, nobody is surprised to see you bashing Canon's products. As usual you don't prove your point to why say it's a failure. It's like you didn't get the idea of this product. It's  a consumer camera providing high margins for Canon. A great platform for them to start developing a whole new series of lenses for. I would say it was smart of them to start by launching the expected high volume model ahead of any higher end product. They get the word out, they get to sell a lot of lenses going with it and finance further development for this platform.

Canon being the dominant player in the camera market will have resources to bring to market a number of interesting products should they see this segment grow further.

I think I'm going to have to side with Ricku on this one.  Canon went the aps-c route, which is better than another company that I won't mention, but it's still something that's been around for a while.  So now we're stuck with something that has specific lenses that won't be of any use to a full-frame sensored mirrorless if they choose to go down that route in the future.

Part of being the best camera manufacturer in the world, is using your dominance in the industry to bring innovation and new ideas to the table that your competitors simply can't afford to compete with.  Canon could have easily churned out a mirrorless with a 5d mark ii-like sensor in it with a similar body style to the EOS-M, and kept it priced competitively.  Sure it isn't necessarily the epitome of innovation since Leica has been doing it for years, but at least it would be light years ahead of Canon's competitors.  And don't tell me the glass would be way more expensive - there are plenty of good cheap Canon full-frame lenses, they could easily make new ones for a mirrorless.

It's not like the EOS-M is a bad camera, it's the what-if that's disappointing.

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Contests / Re: Gura Gear Giveaway!
« on: December 07, 2012, 05:09:37 PM »
I want to win! Haha  ;D

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