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Messages - CarlTN

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16
Lenses / Re: Canon IS Primes for landscapes?
« on: May 01, 2014, 03:57:59 AM »
One major advantage of the 24-70 f/4 L: it has the same filter diameter as my EF-S 17-55 (both 77 mm).

This means I can keep using my filters (for instance B+W XS-Pro Pola and Hoya NDX400) without using step-up rings.

The 24-105L also uses 77mm filters, and is not that far behind the 24-70 in image quality...also costs less and gives more reach at the long end.

17
Lenses / Re: Canon's f/1.2's: What is really going on?
« on: May 01, 2014, 03:32:47 AM »
If you have been looking at images taken at f1.2 then I guess it is because the 85 is significantly sharper than the 50 at this aperture:

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=403&Camera=453&Sample=0&FLI=0&API=0&LensComp=397&CameraComp=0&FLIComp=0&APIComp=0

Clearly the 85 is a much more expensive lens, but the 50 is hardly cheap. I presume on the 85 focal length it was possible to achieve excellent bokeh with more chromatic aberration correction than on a 50 focal length.

There have been a lot of helpful replies to my original question, including Sporgon's link (which I've already thanked him for).  This link did plenty to put me off, but Neuro's discussion of the focus shift issue also dissuades me--I was looking for something a little wider than the 85mm 1.2 and with less of a minimum focusing distance. 

Right now I can confidently work from three feet to my subject with the 85mm, but, if I'm understanding the focus shift problem, the "real" working distance with the 50mm when using AF is about four feet.  While there might be times I used Live View for static subjects, I'd mostly be using this for creative portraits of paying customers and soon-to-be-delivered first child.   ;D

Another little twist somebody added to this thread was a mention of the 50mm 1.2 being improved in and after 2010...Does that mean the link referred to in Sporgon's post is now out of date???


The "sub-thread" about changing lenses and gear handling in general is interesting.  The photographer I mentioned (she holds one lens between her knees when swapping out) is among the higher end (price-wise) photographers in the southeastern US.  She takes good care of her gear, but when she is working a wedding or commercial project, she is focused 100% on getting the job done superbly.  (I believe she began her career as an army photographer in the Middle-East.)  She does keep a second camera close by (usually held by her assistant), but she happens to be only 5' tall, and her style involves a lot of kneeling down and even laying on her belly or back, so having two cameras around her neck just wouldn't work.

I read some time ago in a Moose Peterson blog about metal particles being a component of sensor dust, and he recommends wiping the lens and body mount rings fairly often to reduce the amount of particles which get intot the camera.

As for myself, many fellow photographers laugh at me because I have to put my camera down and the lens I want to put on it down to change.  I've simply never developed the confidence to swap lenses regularly while standing, though having a vest pocket does make it possible for me.  I try to always keep the body facing down to reduce dust falling in (though I know dust swirls up a lot too); and I try to switch very fast.

I've lost shots at times because I was too worried about switching to the appropriate lens during the extreme pollen times we have in our area--especially on windy days.

In a way, this discussion of changing lenses is pertinent, because many of us seem to agree that both the 50mm and the 85mm are lenses for specific shots, not for the majority of work at an event.  Having the confidence and competence to swap out quickly when needed is, in my opinion, one of the basic requirements of a topnotch photographer.  Otherwise, why use a DSLR?  I wish I could get faster and not be so worried about dust.

Very good points, and well stated too, thank you.  However, in my opinion, or at least for me...it's not an issue of "confidence".  It's an issue of "consciousness".  But I agree, if I was making $8k a week shooting weddings (during the wedding season), I would not give a second thought to switching lenses quickly, or doing whatever I needed to do, to get the job done.  (I don't know if I could hold something between my knees, due to my anatomy, but I'm willing to try it sometime...haha.  My thighs are not small, and it's not fat.)  Unfortunately I do not make enough money from my photography, to take such an approach with my gear.  Nor do I want to need to.  And about pollen...well, that can get inside your lens, even if you don't take it off the camera (and even if it is weather sealed).  I don't have the "confidence" to rip my lenses down and wipe the internal dust out on a regular basis, though I'm sure some on here not only do it regularly, but have done it hundreds of thousands of times, etc.

Also agree with the point about the metal fragments...but I suppose since the mount has a spring, that makes everything fine, there's no metal fragments.  I can sleep better now.

If the reason to own an SLR, is to change lenses as much as possible...that's a race I don't feel the need to compete in.  I change lenses when I need to, and try to avoid doing it outdoors.  I am a neat freak that way.  Others aren't, and that's fine.  I don't miss shots too often doing this.  Obviously it depends on how often you need a different lens.  Again I would own more than one body, and work around that.   

18
Lenses / Re: Canon's f/1.2's: What is really going on?
« on: May 01, 2014, 03:15:28 AM »
Wait a second, did someone just compare camera lenses to car pistons?!?!

Yep, that is the kind of "reasoning" we have to try to dispel sometimes.

Not the best analogy maybe, but if you try to read what I said rather than trying to take one sentence out of context, you might understand.  THERE IS METAL TO METAL CONTACT.  Your reasoning is, there is not enough metal to metal contact to cause any "appreciable" wear.  I say, there is certainly metal to metal contact that causes wear, when people rush to change lenses...as if they are changing wheels on an F1 racecar.  Oops, there's another car analogy!  My whole point was, the mount is far from indestructible, and care should be taken when changing lenses.  If you are just wanting to argue, go ahead, but you have to admit, I have a point.

Hold on, let me post under another name to egg this on...oh wait, I'm above that.   ;D

If you really must worry about your lenses, worry about scratches, oxidation and discoloration, mould growth, wear and tear on the focus and zoom mechanisms.  The lens mount is the least of all problems to worry about. Just dont carelessly ram it on the camera and you should be fine for 20 years.

I worry about those things too.  And the 1D4 I rented, showed signs of people ramming the lens on the camera, and even missing the mount entirely.  In the past, I've witnessed people just piling cameras/lenses mounted on tripods, on top of each other into the back of an SUV, as if they were garden shovels!  They were in a hurry to get on the road, and nothing was more important than that, apparently.  The clanking sound was the equivalent to a human being flogged.  Maybe I am too sensitive to it, but I don't like the idea of people being careless, and not appreciating that what they have, cost something, and took a lot of effort to design and manufacture.  And that someday, some poor soul will very likely be buying it, either from them, or someone else (at a yard sale even)...and will say "this one's seen some action!  What a shame...".  To some people, scratching a D700 and its lens, against 8 other cameras/lenses/tripods/heads (total retail had to be $10,000 +) does not even register, I guess.  I just have no respect at all for people like that.

This is now way off the 50 f/1.2 topic, I apologize for my part in it!

For your own sake, avoid watching DigitalRev's youtube videos at all cost.  :o

I like the videos I've seen from them.  If something is done in a humorous context by people who can afford to ruin cameras, so be it.  I just didn't like seeing people be so careless and unconscious of what they were doing.

19
Photography Technique / Re: How do I get the whole picture sharp?
« on: May 01, 2014, 03:10:05 AM »

Well am I wrong?

About their philosophy?  No, but my point was, it's their magazine.  People with power tend to have things their way.  Why don't you start a magazine?  I wonder if that is even possible now.  They all lose money.  But I do prefer to look at one that is printed well, rather than a screen.  Call me old fashioned, but there it is.

My point wasn't about their philosophy, or ownership, I just stated that your editors opinion is incomplete, it is like saying the answer is 42, well yes as we all know it is. But what is the question that arrives at the answer?

Stating diffraction at f14 as a limit displays a fundamental lack of understanding of what diffraction is and how aperture interacts with it, without knowing the sensor size/crop/reproduction ratio, f14 is a meaningless number. If they said f14 on a 135 format camera we wpould know that for consistency we could submit f8 images from an APS-C and f96 images from an 8"x10".

Thankfully they are not my editor...

20
Photography Technique / Re: How do I get the whole picture sharp?
« on: May 01, 2014, 03:06:27 AM »

In macro photography, if you want to get your subject completely in focus you should try focus stacking:


Focus stacking is both time consuming, and consumes more storage space, and more processing power.  Using apertures smaller than f/11 can be perfectly acceptable, in practice...

For example, magazines such as "Nature Photographer", rarely even include landscape images that were shot at wider than f/14 aperture (whether that is always the right philosophy, might be up for debate.
As photographers, it's our judgment call, based on our experience and our willingness to commit time...as to which technique we use.

The herewith discussed example is an example of macro-photography; and if you follow the link I have provided you can clearly see the effect of diffraction on sharpness. At closer focusing distances even if you go to a setting like f22 or f32 the DOF is on the order of milimeters. Therefore, if your subject is not perfectly flat (like a leaf having water droplets) and a setting like f13 does not help to have both center and corners sharp, taking a few more pictures (for this examplea stack of 5or8 pictures) and stacking them will not take that much space or need higher processing power. Of course if you go to extreme cases, stacking can be very time consuming.

Whether you should go to stacking or just use a smaller aperture, the decision will depend on the specific purpose of the photograher, and there may not be one true answer...

For landscapes I have not used stacking, using apertures like f16 (for APS-C) or f22(for full-frame), and setting the focusing distance to hyperfocal distance yields very good results; however the example we have discussed here was about a close-focus distance (macro) subject. In landscaped the subject can be meters/or even kilometer away from the sensor !

Happy shooting,

I never said your subject was not about macro.  But even with macro, it depends on the actual focus distance, and the focal length used...but most especially, whether the subject is flat or not.  Again, for a flat leaf that is perpendicular to the sensor, I see no need for focus stacking.

21
Lenses / Re: Canon's f/1.2's: What is really going on?
« on: April 30, 2014, 02:55:22 AM »
Wait a second, did someone just compare camera lenses to car pistons?!?!

Yep, that is the kind of "reasoning" we have to try to dispel sometimes.

Not the best analogy maybe, but if you try to read what I said rather than trying to take one sentence out of context, you might understand.  THERE IS METAL TO METAL CONTACT.  Your reasoning is, there is not enough metal to metal contact to cause any "appreciable" wear.  I say, there is certainly metal to metal contact that causes wear, when people rush to change lenses...as if they are changing wheels on an F1 racecar.  Oops, there's another car analogy!  My whole point was, the mount is far from indestructible, and care should be taken when changing lenses.  If you are just wanting to argue, go ahead, but you have to admit, I have a point.

Hold on, let me post under another name to egg this on...oh wait, I'm above that.   ;D

If you really must worry about your lenses, worry about scratches, oxidation and discoloration, mould growth, wear and tear on the focus and zoom mechanisms.  The lens mount is the least of all problems to worry about. Just dont carelessly ram it on the camera and you should be fine for 20 years.

I worry about those things too.  And the 1D4 I rented, showed signs of people ramming the lens on the camera, and even missing the mount entirely.  In the past, I've witnessed people just piling cameras/lenses mounted on tripods, on top of each other into the back of an SUV, as if they were garden shovels!  They were in a hurry to get on the road, and nothing was more important than that, apparently.  The clanking sound was the equivalent to a human being flogged.  Maybe I am too sensitive to it, but I don't like the idea of people being careless, and not appreciating that what they have, cost something, and took a lot of effort to design and manufacture.  And that someday, some poor soul will very likely be buying it, either from them, or someone else (at a yard sale even)...and will say "this one's seen some action!  What a shame...".  To some people, scratching a D700 and its lens, against 8 other cameras/lenses/tripods/heads (total retail had to be $10,000 +) does not even register, I guess.  I just have no respect at all for people like that.

This is now way off the 50 f/1.2 topic, I apologize for my part in it!

22
Landscape / Re: Waterscapes
« on: April 30, 2014, 02:41:00 AM »
A change of pace from all these razor sharp shots  ;)

Did you just focus close on nothing to get the blurring?

It was shot on a 28 mil at about f2.2 and I focused on the tree branches, either above or on the reflection in the water, I can't remember. At a focusing distance of about 3m the dof was about 1.5m so I had to focus on a specific part of the picture that I wanted in focus. There was a little mist rising from the pond which helped.

Interesting.  Did it take a few shots to get the focus you wanted?

23
Photography Technique / Re: How do I get the whole picture sharp?
« on: April 30, 2014, 02:38:38 AM »
For example, magazines such as "Nature Photographer", rarely even include landscape images that were shot at wider than f/14 aperture (whether that is always the right philosophy, might be up for debate...but the editor certainly voices their opinion in favor of it, and very often includes it in the text with the image).  In those cases focus distance is not only not in the macro realm, but is usually more than 10 feet from the camera, and on a wider angle lens to boot.  Yet at f/14, the lens is yielding noticeable softening at the pixel level, due to diffraction.  But the 8.5 x 11 full page (or sometimes smaller) prints in the magazine, do not appear soft.  And in most cases, there was no focus stacking.

As photographers, it's our judgment call, based on our experience and our willingness to commit time...as to which technique we use.

Clearly the editor doesn't know what they are talking about, had the same problem when they all insisted we had to have 360dpi for magazines. F14 on what format size?

A 135 format f14 gives the same diffraction as f8.75 on an APS-C and f96 on an 8"x10".
 

I suggest you write the magazine a notarized letter of complaint.  I'm sure the editor will realize they are wrong and you are right, and will issue a front page apology in the next issue, for the error in judgment over the years.  This should fix the problem.  If not perhaps organize a protest rally around their headquarters, that will teach them a lesson they will never forget!  Those always work exactly as intended...and are never a waste of time.   :)     

Well am I wrong?

About their philosophy?  No, but my point was, it's their magazine.  People with power tend to have things their way.  Why don't you start a magazine?  I wonder if that is even possible now.  They all lose money.  But I do prefer to look at one that is printed well, rather than a screen.  Call me old fashioned, but there it is. 

24
EOS Bodies - For Stills / Re: Backup for 6D for Wedding Photography
« on: April 29, 2014, 09:37:09 PM »
Hey everyone,

I am new to the forum and this is my first post here. Up until this year I have mainly shot family portrait sessions but this year I decided I wanted to start second shooting weddings. I shot one a week or so back and had a blast and I have quite a few more scheduled now for this year for that photographer. I want to purchase a backup body for my 6D but I am unsure of what to purchase. Any advice appreciated :

Most wedding pros seem to use the 5D3 (or so I am told, and so I gather).  Given this, a better scenario would be to use the 6D as a backup to the 5D3, or else for "second shooter" usage.  That said, I am not a wedding pro, and so I don't ever know what the hell I'm talking about!

25
Landscape / Re: Please share your snow/ Ice Photos with us in CR.
« on: April 29, 2014, 09:34:21 PM »

Nice to see you posting again, Canuck!

Thanks, Carl. I haven't been spending enough time here, lately.  ;)

You're welcome!

26
EOS Bodies / Re: New Sensor Technology Coming From Canon? [CR1]
« on: April 29, 2014, 09:32:59 PM »
It depends on what the improvement is and how much it costs to implement.  The rumor (although likely false) suggests an improvement in yield, which is where there's a major difference between FF and APS-C.  Sensors are cut from round silicon wafers, and according to Canon a single wafer can produce 20 FF sensors or ~200 APS-C sensors. 

HMM! This is interesting. If Canon is producing ~200 APS-C sensors per wafer, and only 20 FF sensors per wafer, then that means they are already producing APS-C sensors on 300mm wafers, but are still producing FF sensors on 200mm wafers. If you run the numbers, the raw number of full APS-C sensors on a 200mm wafer is 94, on 300mm wafer is 212; the raw number for full Ff sensors on 200mm wafer is 36, on 300mm wafer is 81. Factor in losses, you get a bit less than 200 APS-C/300mm wafer, maybe 20 FF/200mm wafer. I suspect that the actual number of total FF sensors is less than 36, since every time I've seen a photo of large sensors on a wafer, there is usually plenty of blank space and an unetched border around the edge. So maybe Canon gets 190 APS-C out of a 300mm wafer, and indeed only about 20 FF out of a 200mm wafer. Assuming similar losses with larger wafers, Canon should get almost 70 FF sensors out of a 300mm wafer if they do indeed make the move.

How about a hypothetical example…  Say it costs $20,000 for the raw silicon wafer and the stamping and cutting (I have no idea how wild-assed that guess is).  That means a FF sensor costs $1000 and an APS-C sensor costs $100.  Now, say there are on average two random local defects per wafer that result in the loss of the sensors where they occur.  FF production takes a 10% hit on yield, whereas APS-C takes only a 1% hit on yield.  Taking QC defects into account, the cost of a FF sensor is $1111 and an APS-C sensor is $101.  Now, suppose this new process cuts the defect rate in half, to one per wafer, and increases production costs by 2% per wafer.  That drops the cost of a FF sensor to $1074, a 3.3% savings.  However, that 'improvement' results in an APS-C cost per sensor of $102.50, an increase of 1.5% per sensor for APS-C production.

Sell 5,000,000 FF cameras and save $37 each and that's a 185 million dollar profit….
Sell 100,000,000 APSC cameras and spend an extra $1.50 each and that's a 150 million dollar loss....

Now which pile of money do you think Canon would go for first?   :)

Granted, this is only a hypothetical example.  Hwever, it does demonstrate one scenario in which application of a process improvement for FF production would not be cost-effective when applied to APS-C production.

I totally agree. I think increasing yield on the FF sensor front is really where they can save the most money, especially if they are still using 200mm wafers. They have to waste a proportionally much larger area of a 200mm wafer than a 300mm wafer when fabbing FF sensors.

They never mention a 12 inch wafer, they say they get 200 ASP-C sensors of an 8 inch wafer.
Quote from the white paper:

an 8" diameter wafer could cost as much as $450 to $500, $1,000 or even $5,000. After several hundred process steps, perhaps between 400 and 600 (including, for example, thin film deposition, lithography, photoresist coating and alignment, exposure, developing, etching and cleaning), one has a wafer covered with sensors. If the sensors are APS-C size, there are about 200 of them on the wafer, depending on layout and the design of the periphery of each sensor. For APS-H, there are about 46 or so. Full-frame sensors? Just 20.


8 inch is 8*2.54mm = 203.2 mm
The total surface area of this wafer is π/4*203.2^2 = 32429 mm^2

Surface area of ASP-C => 330mm^2
32429/330=98.3
Even if they didn’t have any losses they wouldn’t get 100 sensors.

Surface area of FF => 864mm^2
32429/864=47.41

If they can only get 20 FF sensors out of that, they have about 58% losses. 

This is an 8 year old white paper and nobody mentioned these mistakes before?

That's very interesting if indeed that does translate to about 58% (or 47% !!) full frame sensor losses per wafer, even if it was 8 years ago.

27
Photography Technique / Re: How do I get the whole picture sharp?
« on: April 29, 2014, 09:28:29 PM »
For example, magazines such as "Nature Photographer", rarely even include landscape images that were shot at wider than f/14 aperture (whether that is always the right philosophy, might be up for debate...but the editor certainly voices their opinion in favor of it, and very often includes it in the text with the image).  In those cases focus distance is not only not in the macro realm, but is usually more than 10 feet from the camera, and on a wider angle lens to boot.  Yet at f/14, the lens is yielding noticeable softening at the pixel level, due to diffraction.  But the 8.5 x 11 full page (or sometimes smaller) prints in the magazine, do not appear soft.  And in most cases, there was no focus stacking.

As photographers, it's our judgment call, based on our experience and our willingness to commit time...as to which technique we use.

Clearly the editor doesn't know what they are talking about, had the same problem when they all insisted we had to have 360dpi for magazines. F14 on what format size?

A 135 format f14 gives the same diffraction as f8.75 on an APS-C and f96 on an 8"x10".
 

I suggest you write the magazine a notarized letter of complaint.  I'm sure the editor will realize they are wrong and you are right, and will issue a front page apology in the next issue, for the error in judgment over the years.  This should fix the problem.  If not perhaps organize a protest rally around their headquarters, that will teach them a lesson they will never forget!  Those always work exactly as intended...and are never a waste of time.   :)     

28
Lenses / Re: Canon's f/1.2's: What is really going on?
« on: April 29, 2014, 09:19:47 PM »
Wait a second, did someone just compare camera lenses to car pistons?!?!

Yep, that is the kind of "reasoning" we have to try to dispel sometimes.

Not the best analogy maybe, but if you try to read what I said rather than trying to take one sentence out of context, you might understand.  THERE IS METAL TO METAL CONTACT.  Your reasoning is, there is not enough metal to metal contact to cause any "appreciable" wear.  I say, there is certainly metal to metal contact that causes wear, when people rush to change lenses...as if they are changing wheels on an F1 racecar.  Oops, there's another car analogy!  My whole point was, the mount is far from indestructible, and care should be taken when changing lenses.  If you are just wanting to argue, go ahead, but you have to admit, I have a point.

Hold on, let me post under another name to egg this on...oh wait, I'm above that.   ;D

29
Pricewatch Deals / Re: Deal: Canon EOS 5D Mark III Body $2559
« on: April 29, 2014, 08:57:29 PM »
If anyone wants to save money, they should wait for the holidays, or else wait for a "refurb sale" from Canon USA (and sign up for the updates on canonpricewatch...also consider camel x3 for amazon price updates).  Or you could consider buying used.

I have a feeling the 5D3, full USA model, will sell new at or under $2450, sometime in the holiday season.  And of course it will go well below that, if you factor in lens kit deals (it's already done that this past holiday season).  I wonder just how low it will go?  Also wonder if there will be a 5D4 development announcement sometime in 2015, or before?  Surely there will be a rumor of one in development, if not an announcement.  Of course whatever the next full frame body that gets announced (if it's not the 5D4 replacement), might factor in to the timeline of a replacement.

That is assuming that the refurb store doesn't sell out nearly immediately.  I've had my eye on a couple lenses, but they sell out even before it goes on sale.  I got my 5D3 more than 1.5 years ago for 2500.  I'd rather get one of these gray kits new with a store warranty than buying a used unit from an unknown source.  Who knows why the seller is selling it and if he's being 100% truthful.

The refurb store does not always sell out immediately.  If you don't like buying used, it's your choice.  I don't prefer it either, but I have (and not just photo equipment).  It's worked out fine about 98% of the time, for me.  I've also sold many things used.  Who knows what I've done with my stuff though, I might have used it to dig a ditch!  I mean, who even knows if you are being 100% truthful right now?  All we can do is take people at their word, when dealing with them.  If you choose not to, it might become difficult for you to deal with people, and vice versa.

Read what I wrote:  I didn't say it always sells out immediately.  Although if you'd like to help get me a 300L f/2.8 II IS at 20% the refurb price, then I'll gladly accept your help.

I buy used when the price is right and when it's available through the refurb store.  Two of the lenses I bought used were misrepresented, and that was from people with 100% ratings and dozens of transactions.  One had been knocked hard enough to have the filter threads replaced but had it repaired by Canon but did not disclose it ( I found the Canon repair report in the box).  Another had a faulty AF module.  So that is more than 20% of my lens transactions from supposed "good" sellers.  If I can find it new/refurbed for a price close to used, then I'm not buying used.  It is not an issue of me not taking people at their word but them misrepresenting something that they are contractually supposed to disclose as TOCs for using the sites.

Sorry for your luck, and I don't know how I could help you buy a 300 f/2.8 refurb.  If it means I get to use it for a few weeks before sending it off to you, I'll chip in $100.  How does that sound? 

Not all sellers are the same.  Certainly there are bad apples out there, and there are also bad buyers out there too.  I encountered one a couple of months ago.  I wanted to go hunt him down and beat his ass into the dirt (since I knew his address), but I figured it was more mature to suck it up and deal with it.  It wasn't worth going to jail over. 

30
Landscape / Re: Waterscapes
« on: April 29, 2014, 08:52:03 PM »
A change of pace from all these razor sharp shots  ;)

Did you just focus close on nothing to get the blurring?

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