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View Full Version : Photographers - a depth of field question


Shaggy Sheep Driver
21st Jan 2014, 21:01
Years ago with me Canon AE1 I could easily blur the background of a shot to highlight something in the foreground by opening up the aperture and focusing on the foreground object. Why doesn't the same technique work with my Canon G12? No matter how I set it up, the background stays in focus when the shot is focused on the foreground! What am I doing wrong?

PPRuNe Towers
21st Jan 2014, 21:15
Focal length of the lens and sensor size are the culprits Shaggy,

You aren't doing anything wrong at all. The G12's sensor is far smaller than the film area of your 35 mm film frame which in turn was far smaller than that of a Hasselblad and that was far less than an old fashioned plate camera.

The larger the recording surface - whether film or digital - the less the depth of field at a given aperture and angle of view. And, sadly, vice versa for you.

Therefore the smaller sensors - cameraphones or compact cameras - really struggle to give the isolation you are hoping for even when wide open. Zooming in as far as possible with your widest aperture will give you the best possible simulation of what you are looking for.

Rob

ExSp33db1rd
21st Jan 2014, 21:20
Interesting - I've just bought a G12, and am slowly (!) getting to grips with it courtesy of a 212 page User Guide !! I insisted on a G12 over the later models offered, 'cos Canon have gone back to the fixed screen concept, ie. once again done away with the articulated screen. Crazy.

back to subject ........ don't know, yet, but doesn't selecting the aperture priority mode and selecting a low 'f' No. e.g. f2.8 do it ?

Sorry if I'm teaching you to suck eggs, but I'll be interested in the answer, too !

John Hill
22nd Jan 2014, 03:57
If anyone is finding this hard to grasp just remember that a pin hole camera has infinite depth of field!:)

Bushfiva
22nd Jan 2014, 04:20
Doing a quick bit of calcs here, let's consider a portrait shot:


100 mm lens on a full-frame 35 mm camera, using f/2.8 gives you a DOF of around 42 cm at 5 meters, so your subject's head is nicely in focus and the background isn't.


On a G12, you're shooting at 25.4 mm to get the 100 mm equivalent, and your DOF is around 1.6 meters. You'd have to be below f/1 (DOF 55 cm) to get anywhere close.


As you use longer focal lengths, the problem is accentuated of course: on a G12 at 200 mm equivalent, somewhere just above f/5.6 you DOF becomes infinite.


This is why people with smaller sensors find themselves shooting closer to the subject to get the same DOF control they're used to with 35 mm full frame. For portraits, that brings its own set of problems, including big noses (the subject's nose it appreciably closer to you than his/her ears) and uncomfortable subjects (there's a camera staring up his/her nose).

A A Gruntpuddock
22nd Jan 2014, 04:48
Try standing further away and use a long focal length to compensate.

Use manual settings to keep the aperture as wide as possible.

chksix
22nd Jan 2014, 06:43
Train in the sim before takeoff ;)

Photography Students | CameraSim (http://camerasim.com/photography-students/)

chuks
22nd Jan 2014, 07:34
I would suggest buying a nice, used Canon 5D. For about $700 USD you get a full-frame SLR that handles very much like your old AE-1, without all the built-in limitations of a "point-and-shoot" camera such as the G12.

I have used both the G10 and the G12 and they are nice cameras, but their basic design is for something very different from what you want to do. For around the same amount of money, you will probably be happier with an obsolete, used "prosumer" 5D than with a new "point-and-shoot" G12, if you want to do anything more than just grab decent holiday shots.

Loose rivets
22nd Jan 2014, 07:39
Try standing further away and use a long focal length to compensate.

Or alternatively, only shoot portraits in the open on foggy days.:}

Hat, photo-floods, door . . .


Those sims are good, aren't they. I wish I'd had something like that in the 60s. My lovely old Yashica Pentamatic, despite its name, didn't even have a light meter. However, it was very stable simply due to its vast mass.

This is somewhat germane.

http://img.photobucket.com/albums/v703/walnaze/Family/GrantsPrezzy585_zps950355d5.jpg (http://smg.photobucket.com/user/walnaze/media/Family/GrantsPrezzy585_zps950355d5.jpg.html)


I've always been mystified by this pair of photos. They must have been taken by a street photographer and I would have thought taken with a wooden box with two lenses. But I don't know. The lady on the right is my great aunt, then c 38. She was born in 1885-ish.

It seems the subjects are just getting too close to be in perfect focus. On the cusp. With a loupe one can see incredible detail in the shop window and the focus at infinity seems good. How could they have snapped shots two seconds apart in those days if not with double lens?

Bushfiva
22nd Jan 2014, 07:46
AAG, you read it's a G12, right? He's got at most 140 mm equivalent at F4.5. His DOF at 15 meters is more than 20 meters...

gingernut
22nd Jan 2014, 08:44
would it be worth buying a "prime" lens ??

bricquebec
22nd Jan 2014, 08:57
I had a G10 followed by a G11 and find the G11 wonderful for putting in the pocket, and taking out 'just in case'. (and the swivel viewfinder is a gem). However, I realised that, as soon as I could afford it, I had to buy a true SLR for any 'serious photography'. Horses for courses.

A A Gruntpuddock
22nd Jan 2014, 09:40
"How could they have snapped shots two seconds apart in those days if not with double lens"

Don't know about the number of lenses but I think they had a large winding handle on the side - took one revolution to move the film on, but my memories of the subject are about 60 years old so may not be reliable.

BlueDiamond
22nd Jan 2014, 10:37
"How could they have snapped shots two seconds apart in those days if not with double lens"
Using two cameras perhaps?

mixture
22nd Jan 2014, 11:04
Why doesn't the same technique work with my Canon G12? No matter how I set it up, the background stays in focus when the shot is focused on the foreground! What am I doing wrong?

What's the aperture of the lens on your G12 ? And also, I assume you're in Aperture or Manual mode and and have set your focus points correctly (or have tried focusing manually).

meadowrun
22nd Jan 2014, 11:05
How could they have snapped shots two seconds apart in those days if not with double lens?

Pure speculation here.... Photographer was using some kind of tourist camera (pay for pic) with double vertically mounted lenses, double negatives and double shutters. Judging by the differences in footfalls by your aunt and the other lady, the time difference is between 1/4 and 1/2 second between shutter openings, either by an auto mechanism or very fast finger.

The focus anomaly is due to the lower negative not being held as securely flat in the camera as the upper one.

mixture
22nd Jan 2014, 11:05
would it be worth buying a "prime" lens ??


No need for a prime lens, a decent zoom lens will do as long as it as the right aperture (e.g. the Nikon 24-70 f/2.8 does a lovely impression of a prime lens for most purposes :cool:)

Old Photo.Fanatic
22nd Jan 2014, 13:54
In anticipation the three examples here may be of help.

All taken as opportunistic photographs with no real thoughts of the Depth of field. but very pleased with the results.
My normal output being aircraft.

All taken with my Nikon 80-200mm F2.8 zoom lens.
With a small amount of "Cropping" to the result.

My back garden.
Taken at f2.8, 1/1000 sec at 200mm

http://i611.photobucket.com/albums/tt200/phredd10/Depth%20of%20Field%20Examples/Backgardenfence_zpsab2117ee.jpg


At RAF Waddington. in a hedgerow.
Taken at f8, 1/250 sec at 185mm

http://i611.photobucket.com/albums/tt200/phredd10/Depth%20of%20Field%20Examples/WaddingtonJuly2008CT_01Burke_zps5be62d93.jpg


At Marseille Airport.
Taken at f5.6, 1/320 sec at 200mm

http://i611.photobucket.com/albums/tt200/phredd10/Depth%20of%20Field%20Examples/QCloseup_01_zps4e120b6b.jpg


OPF

Shaggy Sheep Driver
22nd Jan 2014, 15:12
Thanks guys. PPRuNe Towers seems to have it - it's endemic in a small-sensor digital camera to suffer a wide DOF even when the aperture is manually set to max.

Loose rivets
22nd Jan 2014, 20:01
henry, just think what the inventors of the falling plate camera would have thought of that. I had no idea such a thing existed. I do however, recall a double lens on a wooden box (quite unrelated ) which would tally with meadowrun's description. The timing of the step is something I've tried to work out, but long forgotten what conclusion I came to. Don't think, a-hem, great-aunt would have gone far in 1/4 sec. ;)


Thanks guys. PPRuNe Towers seems to have it - it's endemic in a small-sensor digital camera to suffer a wide DOF even when the aperture is manually set to max. This is another thing I was unaware of. I recall hearing of the bigger matrix in the Nikon D700 I think it was, and all that entailed. (Buying a new set of lenses was one of them. :uhoh: ) but I never considered the opposite effects.

bugg smasher
22nd Jan 2014, 20:09
A bit of clever pixel surgery in Photoshop or After Effects should fix you right up.

meadowrun
22nd Jan 2014, 20:12
Don't think, a-hem, great-aunt would have gone far in 1/4 sec.

True. I look at the position of her left sole vs. the pavement crack in the two frames. The only motion wasn't forward, it was her sole coming down 3 inches to the pavement.

awblain
22nd Jan 2014, 20:20
If you want something pocketable with controllable depth of field, a "mirror less SLR", like the Sony NEX3-7, with a squat lens, might be worth considering.

I tend to think their performance is fairly good given their small size. They're not perfect, but miles better than a "compact camera".

gingernut
22nd Jan 2014, 20:30
Think the prime lens offer a larger aperture, at a reasonable price. Page 11 http://www.photoanswers.co.uk/upload/3306/attachments/using-your-lenses.pdf

I am still learning though :-)

chuks
22nd Jan 2014, 20:41
Digital stuff drops in price so quickly that there are a lot of really good cameras available for relatively very little. A Canon EOS 5D sold new for something like $2,500 USD ... You can get a very clean example now for about $700. That's a full-frame SLR that makes really good images, for the same price as one of these fancy new cameras crammed with state-of-the-art goodness that suffers from some inherent design compromises and will be sadly obsolete by next year at this time.

Remember: If you can buy it, it is obsolete!

The term "prime lens" generally means a fixed focal length lens that is the same focal length as the diagonal measure of the film negative or the imaging chip. For a 35-mm. camera or a digital camera with a full-frame chip that is 50 mm. If you want to do portraiture, though, you may find that a lens of around 100 mm. is more suitable, while for general photography a lens of around 35 mm. is often more useful.

It's not necessarily so that a "prime lens" will be optically superior; the term has nothing to do with the quality of the lens. Loosely put, a lens with a smaller maximum aperture will often yield higher resolution than one with a larger maximum aperture, and modern zoom lenses are often able to match the quality of older fixed focal length lenses.

awblain
22nd Jan 2014, 20:55
In about 2008 in Kona the Captain of a United 757 took a picture of me in his seat with my (at that point probably about five-years-old) Olympus E1, which I'd bought used not long before.

"What's this?" he asked.

"It's a supposedly professional SLR with a decent CCD detector, but it was quite cheap because it's a few years old", I said. "They don't make them anymore, but it's good and works better than anything new for the price."

"This is a 757…", he replied…

mixture
22nd Jan 2014, 20:57
. I recall hearing of the bigger matrix in the Nikon D700 I think it was, and all that entailed. (Buying a new set of lenses was one of them. )

Nikon sensors are split into two... DX on the cheap cameras, FX on the expensive ones.

The reason for the associated DX and FX lenses is because the DX lenses accomodate for the smaller size of the sensor in the DX bodies.

DX bodies can use FX lenses, but not the other way around.

bugg smasher
22nd Jan 2014, 21:26
Re zooms, I use DSLR lenses for video, the more inferior zooms tend to breathe considerably, that is, the angle of view changes when focusing, noticeably altering the composition of the shot. One of the finest relatively low cost zooms out there is the Nikon 14-24, much sharper than its Canon counterparts, with very little color fringing and/or chromatic aberration.

Good glass is always a good investment, especially when considering how often camera bodies become obsolete.

nikon 14-24mm | B&H Photo Video (http://www.bhphotovideo.com/bnh/controller/home/search?N=0&InitialSearch=yes&InitialSearch=yes&sts=ma&Top+Nav-Search&Ntt=nikon%2014-24mm)

Loose rivets
23rd Jan 2014, 07:59
Interesting. It puts one in mind of the experiment done to prove horses' feet are all off the ground at the same time. Not really the same I know, as that was a row of separate cameras.

I supposed high speed movie shots with film are obsolete now. Though I'm not sure. Ripping high definition shots from a matrix into storage at thousands of frames per second must be quite difficult.

Mmmm . . . 12,500 in HD.

Get ready for another 20 mins of your life you'll never get back. For me, it was the bio-dynamics that left me stunned.

Photron - Gallery (http://www.photron.com/index.php?cmd=gallery&cid=3&mv=03_01_treadmill_rear)

chuks
23rd Jan 2014, 09:11
That thing with the horse's feet was Muybridge, I believe. He used a row of cameras for that one, triggered in close sequence. There's a very interesting book that came out not so long ago showing all the different subjects Muybridge used: men wrestling, women pouring water ... it's worth a look, if your library has a copy.

Edweard was his first name, changed by himself; he was a real eccentric genius.

Back to cameras: We get color advertising supplements with the local papers, from the local shop of a big chain that peddles electronics and home appliances. Canon SLR kits are always in there, but when you look at the lenses shown you see "EL-S," the designation for the lenses that only function with the smaller sensors. Lenses for the full-size sensors are designated "EL." Of course the adverts don't tell you directly that these cameras, although visually almost identical to the ones with full-size chips, are fitted with smaller chips. You have to read the fine print to see "APS-C," for instance, as the sensor size.

The camera lens projects a circular image that has to reach from edge to edge on the film or sensor, so that the diameter for a full-size chip is 50 mm., the same as for a 35-mm. camera. This means that a 50-mm. lens has a magnification factor of 1. A 100-mm. lens would have a factor of 2 and so on. By extension, if you put a 50-mm. lens on a camera with a smaller chip, then the lens will have a factor greater than 1. On the other hand, if you put a lens for a camera with a smaller chip on one with a full-size chip, then the projected image will not stretch from edge to edge on the chip: the reason that you can use a Canon "EF" lens on a camera designed for an "EF-S" lens, but not vice-versa.

These "point and shoot" cameras exploit this by using shorter lenses to suit their smaller chips, so that a prime lens might be something like 28 mm. instead of 50 mm, and the "zoom" will not need to extend so far as for a camera with a larger chip to achieve equivalent magnification. Another trick is the use of "electronic zoom," simply choosing a smaller area of the chip, fewer pixels, to form the full-size image, instead of changing the lens focal length mechanically.

jumpseater
23rd Jan 2014, 10:36
In answer to SSD's question, it may be technique on his part. I have a G10, I shoot full manual 90%+ of the time and don't have a problem as he describes.

If you have time use the manual focus facility and self timer, you can grab focus the subject and then recompose, self time and it takes the shot with the focus as predetermined. I assume the G11/12's have the same facility.

My G10 has been brilliant and I've done very well out of it, its been a very usefull add on to the DSLR, as has a mate of mine. I've just found the Iphone 5 takes some excellent pictures too. I did try the Sony Experia Z1 phone, but the images from that, despite the advertising, were very poor indeed, so I took it back as not fit for purpose in the image department and swapped up to the Iphone. Shop assisants were gobsmacked until I showed them the pictures made from Lego!

Shaggy Sheep Driver
23rd Jan 2014, 11:44
JS, I do drive the camera manually when trying for narrow DOF shots - with aperture on max, focusing on the foreground object (a recent example as a steam locomotive with sheds some distance away in the background. I focused on the loco using the above technique, but the sheds were still in focus as well, detracting from the main subject.

Tried numerous times. Same result. I find the G12 to be an excellent camera apart from this!

It seems PPRuNe Towers has explained why that happens (second post in the thread).

jumpseater
23rd Jan 2014, 16:00
SSD I shall have a try myself with mine, I know it works on smaller subject matter such as 'a child', but can't recall specifically trying it with something as large as a loco, but I can't see a reason why it won't from my previous G10 results. I normally work at 80ISO and very rarely above 200th.


3 - 2 - 1, Henry!, you're back in the room! :rolleyes:

chuks
23rd Jan 2014, 16:38
These "cameras" often have no electronics at all! No, they can record images using light that causes a chemical reaction on photo-sensitive film that is later developed into "negatives." Then the "negative" can be used to make a "print," a piece of paper you can hold in your hand, a two-dimensional record of three-dimensional reality.

This afternoon the cabinet-maker was here to document the fine hand-work some burglars did on some window frames. He pulled out an i-Pad, saying, "I just got this yesterday." Well, he said that in German, actually, but never mind that now. Then he used his i-Pad to take pictures of the damage while I watched, wondering, "What ever happened to using a camera?" Well, I guess the i-Pad did.

When those fun-loving North Koreans hit us with a big-big EMP, then I shall be out there taking pictures with my Leica, laughing at everyone who's weeping for all the fried electronics. That will show you who's boss. Well, me and John Hill, of course ....

Loose rivets
23rd Jan 2014, 17:18
Oh, you're talking about that darn David Crawford's book again. :ugh: It is a thought though - how we would manage without electronics.

I have the clearest memory of my mum putting a neg over some paper, putting it in a little wooden frame and turning the clips on the back flap. Then it was put on the windowsill to get enough light to make the print. Just post-war, that was.

ExSp33db1rd
23rd Jan 2014, 19:53
......... a neg over some paper, putting it in a little wooden frame and turning the clips on the back flap. Then it was put on the windowsill to get enough light to make the print.That was my Saturday job for my dad - the town photographer - and the paper printed in red. These were the "proofs" of the photo's that he had taken upstairs, in The Studio against a suitably painted canvas background, and if a cheapskate customer didn't choose to purchase any, i.e. just kept the "proofs", then they would continue to absorb daylight until they turned almost black.


It's worse than you think!Yes, my first negatives were made on GLASS ! measuring 12"x10" on a camera about the size of the early TV sets circa. 1950, having first thrown a black cloth the size of a bell tent over my head so that I could manually ( shock ! horror ! ) focus the image on a ground glass focussing screen.

There was the story in those days, told by many a photographic apprentice in The Darkroom, of the photographer photographing a class at a girls' school. As he disappeared under the black cloth, one of the girls asked her friend - "What's he doing ?" and the friend said " He's going to focus" - "What !" said the first girl, "all of us?"

G-CPTN
23rd Jan 2014, 20:02
:ok: . . .

chuks
23rd Jan 2014, 20:31
I was at court in Ikeja, Nigeria, once, trying to get my houseboy thrown into prison for stealing 600 DM. Well, first I tried to get him to pay me back, but then I settled for trying to get him thrown into prison, one of those prisons where they should go Medieval on his nyash and teach him the error of his ways. I failed at both these things, but it was not for want of trying.

Anyway ...

Outside, lined up along the low brick wall fronting the court, were scribes, sat there with typewriters or with just pens and paper, since many people were illiterate and needed someone literate to write for them, and a photographer with a very crude view camera. So I had my picture taken, just to see how that worked.

No shutter, just a little tin can that once held tomato paste to put over the lens, and no film either. Instead, this ingenious man used photo paper and then did a macro shot of the negative paper image to produce the final print, with the little dishes of developer and fixer inside the camera.

It was a really neat portrait he did, a little head shot, one with a real old-timey look to it, but it went missing somewhere along the line. I wish I still had it.

Dushan
23rd Jan 2014, 22:11
When those fun-loving North Koreans hit us with a big-big EMP, then I shall be out there taking pictures with my Leica, laughing at everyone who's weeping for all the fried electronics. That will show you who's boss. Well, me and John Hill, of course ....

The Leica has some electronics, although not necessary to operate, just to measure light. At least mine does, you may have an older one. But I have my Minox (or about 10 of them, actually) they have a light meter but it is not electronic. By the time the Norks hit us I may even have a Haselblad.

chuks
24th Jan 2014, 06:20
You mean "self-powered," I think, from a silicon cell.

Well, when Kim Jong Un drops the Small One on Toronto, or else if your man Rob Ford next gets his hands on a tactical nuke and does something very rash with it, I guess you will find out about EMP and its effects on light meters and "Good luck" to you with that.

The main thing is simply to get out there and take pictures. Too many people nowadays get into gadget fetishism, always needing the latest-latest but forgetting the purpose of the gadgetry. In the case of cameras that must be making images.

There's a trend I have noticed to be growing, people getting very precious about having their picture taken, and particularly having pictures of their children taken. I once wanted a picture of a fountain in a courtyard in Bordeaux, when a small child was playing next to it. As I framed the shot the parents came over and freaked out about the very idea of this child forming part of the image, as if I were some sort of drooling fetishist focused on their unexceptional brat instead of this beautiful fountain. They rushed their little victim away, clucking like wet hens in French, when I suddenly felt a pang of sympathy for the Wehrmacht.

Then we have this "male gaze" business getting traction with the feminists, when that, too, has oozed over into photography.

On the other hand, try looking at the pictures or sculptures in an art museum nowadays, to see if you can get past all these muppets holding up their i-Pads to look at the art on the i-Pad instead of simply using their eyes. It's a very weird trend, the way things no longer happen unless there's an image of the moment they happen. That has turned the moment largely into an act of imaging, and I think that's down to these modern cameras giving a nearly instantaneous image.

Used to be, you wandered around, took a shot, took another, used up a 24- or 36-shot roll of film, which could take days or weeks, got the film developed and printed, which took another week unless you did this yourself, and finally, there were the images of events from a while ago. Now it's this ridiculous, "Look at what I am having for lunch!" business.

I am sure the next step will be spectacles that stream video, so that you can participate in the not-so-really-fascinating lives of others while also putting your own trivial life on show, a "Truman Show."

Can you be a fully formed pop star today without a "leaked" sex video? Henry Fox Talbot, what have you done?

meadowrun
24th Jan 2014, 07:46
And yet 50% of shots were still taken into the sun.

chuks
24th Jan 2014, 09:34
Exposure can often be guessed at with a fair degree of success.

Dushan
24th Jan 2014, 11:14
And film has a much wider latitude than digital cameras, so if you are off by a couple of F stops, you can always adjust during printing.

Shaggy Sheep Driver
24th Jan 2014, 11:21
Crikey, thread drift is alive and well innit!

PPRuNe Towers
24th Jan 2014, 11:34
And some cringingly self assured mistatements.........

Rob

A A Gruntpuddock
24th Jan 2014, 11:47
Used to have one of these Johnson exposure calculators when I was using my Agfa Silette.

Pretty accurate, but the best thing was that you could set the values then snap away without continually being nagged to change something!

mixture
24th Jan 2014, 13:38
And film has a much wider latitude than digital cameras, so if you are off by a couple of F stops, you can always adjust during printing.

Utter tosh.

Shoot RAW and you can claim F-Stops back on digi files from most decent cameras..... obviously you've never played with files from a Nikon D4 or Nikon D800 (cheaper Nikons can also recover to some degree too, I just quoted those two because they have particularly good dynamic range).

Also with digital cameras, instant review and histograms, there's very little excuse for people not to get it right in-camera. You should be aiming to minimise your post time by capturing the best possible image in the first place.

If you want to be really lazy with digital and can't be bothered with (or a too stingy to buy) a decent set of lenses and filters, there's always HDR.

Pelikal
24th Jan 2014, 14:40
Anyone had a go at Focus Stacking? Taking a number of shots, identical but for incrementally adjusting the focus between frames. Then combining the shots in Photoshop or whatever. Similar to the HDR principle but playing with focus rather than exposure.

I don't have a DSLR (:() otherwise I would try it. A quick search for Focus Stacking will describe the process.

awblain
24th Jan 2014, 15:05
Film does have a very very large number of "megapixels", but the chances of any one photon landing on film to set off a silver grain is small.

If you want to gather light, then the electronic detector is definitely the weapon of choice - as long as the detector is centimeters rather than millimeters across.

jumpseater
24th Jan 2014, 15:09
SSD, sorry about the thread drift I mentioned the 'I' word and thought I'd got away with it! The answer to your original post appears to be a mixture of P/Towers answer, and mine. I've got pics of the kids and 'detail' images where the subject is sharp and background blurred. I've also got very few where a large subject, a car, aircraft is sharp and the background either blurred or diffused.

Earlier today I tried re-shooting the car in a daylight bright overcast conditions and was getting the same result as yourself, background in focus. The images where I have a diffused background are low light shots, so I think there's also a light hitting the sensor variation in P/T'statement too. The brighter the light the harder it is with the G10 to get an out of focus background when shooting a large subject. Smaller things like children the background can be diffused easily on 'M' settings.

And just to keep the froth going

http://i29.photobucket.com/albums/c270/2012images/annoychucks_zps10f38cfc.jpg (http://s29.photobucket.com/user/2012images/media/annoychucks_zps10f38cfc.jpg.html)
#AnnoyChucks #ReallyAnnoyChucks #foamingChucks #Chucks #incensed #getapropercamera
#bloodykids #reallyquiteannoyednow #getsometimeinsonny #weneveraditsogood

jumpseater
24th Jan 2014, 15:14
Stacking, get decent software, someone I know uses a hack into the camera on his G10 to stack 'in camera', and cant see why he gets the piss taken out of readybrek halos and lego pictures to his work. Ho hum ....

mixture
24th Jan 2014, 15:32
Anyone had a go at Focus Stacking? Taking a number of shots, identical but for incrementally adjusting the focus between frames.

I think there's a company that makes a camera that does just that (Lytro I think they're called).

chuks
24th Jan 2014, 19:03
Meander, yes. Drift, though, never!

Hey, as long as people are out there taking pictures, whether that is with a Box Brownie, an i-Phone, an i-Pad, a Leica M4, M5, M6, M7, M8, M9 ... whatever, what matters is the act of photography. It can make you see, rather than just look.

Okay, I do tend to froth a bit, especially when it's a matter of not being able to see the art for all those numpties busy taking throwaway shots of same as if they cannot just use the MkI eyeballs they were issued with at birth instead of some stupid electronic toy, but if using your telephone or your i-Pad to take pictures with is what you like to do, well, it's still photography so do carry on.

Loose rivets
24th Jan 2014, 19:12
I want to keep thinking like that, but last summer in the UK I visited a friend who has devoted most of his life to filming. What started as a hobby ended up with a company that films and edits at broadcast quality. He's partly retired now, but I wasn't surprised when he showed me a short film of going along the Norfolk Broads with an old friend. I watched for a while - on a 24" 1080 monitor - and just nodded my approval. A moment later, nodding became difficult as my mouth was hanging open. He'd taken the darn thing with his phone.

The only difference perhaps, he's had years to learn the shots and holding the tiny object still.

Bewildering.

ExSp33db1rd
24th Jan 2014, 20:38
No shutter, just a little tin can that once held tomato paste to put over the lens,............... can witter on all day about expensive technology, but simple hardware can be used remarkably effectively. The early 12x10 cameras I used had no shutter, stop down to around f16,put a lens cap in place, remove the protective sheaf in front of the glass plate, then take the lens cap off for 2 - 3 secs.

A customer once asked my boss how he knew to expose the film for the length of time he did - variable according to daylight, inside, outside, etc. and he replied that all photographers are born with a bell inside their head, and when the bell rang they replaced the cap over the lens.

Seemed to work, but the darkroom staff sometimes had to work wonders when printing the results !!

bugg smasher
24th Jan 2014, 20:41
And film has a much wider latitude than digital cameras, so if you are off by a couple of F stops, you can always adjust during printing.

Perhaps a little outdated there. The new Red Epic Dragon cameras have more resolution than 65mm film when scanned at 4K, not even worth mentioning 35mm film here. Re dynamic range, 65mm film has 14.5 stops, the Dragon sensor 16 stops.

Windy Militant
24th Jan 2014, 21:33
And film has a much wider latitude than digital cameras, so if you are off by a couple of F stops,

Maybe not a big deal with still photography but CCDs and CMOS devices are coming on in leaps and bounds. Consider the HIMO images that are appearing on television more and more.
What was known as high speed photography a few years ago has now moved into the realm of handy cam video equipment.
Whereas thirty years ago to achieve megahertz frame rates you had to have a streak camera and a couple of miles of film.
Twenty years ago you could get imagers that would capture six or eight images electronically.
Today we're looking at trillion frames per second and have video systems that will exceed 100 Khz at mega pixel resolution.
Amazing pitures of a laser pulse imaged at MIT :D
Laser pulse shooting through a bottle and visualized at a trillion frames per second - YouTube

chksix
25th Jan 2014, 08:23
Incredible clip Windy!

A 1/2" sniper bullet would be moving through the frame at a plate tectonic rate.

chksix
25th Jan 2014, 10:57
mfgsQX78hg8

Great explanation of how it's done.

awblain
25th Jan 2014, 10:59
It's rather unfair to digital recording media (in the cm-sized range) to criticize their low dynamic range when compared with film. That really reflects just the speed at which they saturate, since film is so relatively insensitive.

Multiple digital frames with different exposures can be joined, just as could be done with printing on film, to increase dynamic range.

When it comes to grabbing photons, digital detectors now very rarely have anything to give away to film. And with video non-destructive readouts of CMOS sensors, saturation should be avoidable too. How often do you need to record 16 octaves of intensity?

awblain
25th Jan 2014, 16:58
CCDs do have a natural advantage in noise, and can put all their amplifier eggs in a few excellent-performing baskets; however, the cost of the processing electronics necessary to tidy up the XMOS detectors in consumer devices to a decent match is less. The response speed of a newer CMOS camera is way faster than a CCD from 10 years ago.

I'd recommend trying it again.

bugg smasher
25th Jan 2014, 22:33
When it comes to grabbing photons, digital detectors now very rarely have anything to give away to film. And with video non-destructive readouts of CMOS sensors, saturation should be avoidable too. How often do you need to record 16 octaves of intensity?

Well, as far as editors are concerned, that's a complex question, but already settled. In the underwater work I do, we capture RAW, our goal is to manipulate iris in order to expose the CMOS sensor for maximum ambient dynamic range available for a given shot, referenced and confirmed via the onboard histogram camera displays.

The human eye, the astonishing organic adaptability bequeathed us by evolution, is notoriously unreliable in these conditions. In view of that limitation, as long as we nail precise focus for any given shot, challenging in the underwater way of things, the rest is up to the editing team and the very arcane post production magic they engage in.

Rant off, cheers all.

thcrozier
25th Jan 2014, 22:45
Short answer, set the shutter speed as high as possible to still get proper exposure. This should force the aperture wide open and give you minimum depth of field. The effect will be more pronounced at higher zoom levels. That's the best you'll get.

Shaggy Sheep Driver
26th Jan 2014, 09:20
Short answer, set the shutter speed as high as possible to still get proper exposure. This should force the aperture wide open and give you minimum depth of field. The effect will be more pronounced at higher zoom levels. That's the best you'll get.

Yep, that's what I did and still got a carp DOF (i.e still far too deep). It seems to be a limitation of small sensors as PT says in post #2 of this thread.

Here's a failed attempt, with my G12, to lose the arboreal background despite max aperture on max zoom. Foreground and background are slightly out of focus, but not enough:

http://i18.photobucket.com/albums/b132/GZK6NK/IMG_0067.jpg (http://s18.photobucket.com/user/GZK6NK/media/IMG_0067.jpg.html)

El Grifo
26th Jan 2014, 11:42
Well I started off over 35 years ago with a Zenit E and some weird looking Russian enlarger.

I now use Canon DSLR´s in a professional capacity, shooting RAW with minimum fiddling on Photoshop

There is no doubt whatsoever in my mind about the pro´s and con´s of progress.

El G.

thcrozier
26th Jan 2014, 14:50
There is an old adage in photojournalism, "f5.6 and be there", meaning at f5.6 or higher (smaller aperature) you'll probably have enough depth of field to get a decent shot.

Your AE-1 probably had the standard 50mm f1.8 lens, which is quite fast (wide aperture vs focal length). To get the effect you are looking for, you'll need a lens which opens up to at least f3.5, if not f2. The problem is that faster lenses are bigger, heavier, and far more expensive to manufacter because by definition, each full stop wider requires a doubling of the surface area of the glass.

Note that the standard f-stop scale is essentially the previous value multiplied by 1.41, the square root of 2. Hence the familiar 1, 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, etc. scale. As that number goes up, so does depth of field, but manufacturing cost goes down by about the same factor. At the extreme, your lens can just be a pinhole in a piece of paper. Your pictures with that wil be very sharp, and with almost infinite depth of field.

Most modern digital cameras don't have very fast lenses so they can be kept in an affordable price range and compact in size. Plus, a slow lens doesn't have to be focused as critically to give acceptable results for an average snapshot. If you buy a Canon or Nikon DSLR and a 1:1.4 lens, you'll get the effect you seek. These discussions about sensors are interesting, but the sensor (except its size vs focal length, as explained in Post 2) has nothing to do with DOF.

So now the simple answer is this: Just add money. :)

Loose rivets
26th Jan 2014, 16:40
What I'm most astonished by is the news that the watches inner workings on Seiko7A38's forum are often taken with a hand-held compact camera! I'm at a loss. Intending to downsize because of cramped trans-Atlantic cabin conditions, I nevertheless ordered a M42 - Nikon adapter to use my old Panasonic 1:1.4 lens with an extender. It seems now I should have been concentrating on downsizing.

I can't afford the Sony kit that seems to be taking over the world. To get back to my spec, albeit with 24mp? or thereabouts, I'd need nearly $2,000. It is a nice bit of kit, but very, very complex. I'm told it corrects for some of the more common aberrations in its glass. That is serious computing and one wonders just what might go off kilter in years to come in a way that doesn't really make itself clear. (pun intended.)

Anyway, look at this - and if you followed the watch fettling thread I posted on PPRuNe, there is a photo of the best I can do totally misusing my 18 - 200. (it was much better before I smallerized it to fit, but still not like some of the shots on the above forum.)

This is from the site owner's Lumix, and I quote:

Panasonic Lumix FS-15 compact - no tripod - nada - hands free, point and shoot.

Some of the shots on this forum show detail like the scratches on the edges of screw slots - screws that I can barely see without two pairs of specs perched on me nose.

http://www.seiko7a38.com/apps/forums/topics/show/12121578-macro-watch-photography-topic-moved-

thcrozier
26th Jan 2014, 18:06
And a deep depth of field. If you wanted, for instance, to have just the watch face in focus but the wristband out of focus, the Lumix won't do it - unless it has a macro setting allowing you to hold the camera a few centimeters from the subject.

mixture
26th Jan 2014, 19:04
Here's a failed attempt, with my G12, to lose the arboreal background despite max aperture on max zoom. Foreground and background are slightly out of focus, but not enough

As has been said a post or two above mine. What exactly are you expecting on with a cheap lens that only goes as far as f4.5 (according to your EXIF) ?

You're not going to get the sort of lovely soft bokeh you'd get with f2.8 or wider.

If you're not going to invest in better lenses, then you'll have to invest in learning Photoshop. :E

Shaggy Sheep Driver
26th Jan 2014, 19:12
The G12 doesn't have exchangeable lenses. So to go to the bigger lens you're talking DSLR. It's not the cost that puts me one of those, it's the lugging around of a bag of 'gear', including lenses.

That's OK if photography is your prime reason for being out and about, but for me it's not. I need a camera that's easily and unobtrusively carried around, and which gives good results.

awblain
26th Jan 2014, 19:16
Three year old digital stuff is relatively cheap and still abundant.

Don't buy a new LUMIX compact camera (DMC-FS15), buy a used mirrorless LUMIX SLR (G3).

You'll not regret getting better, interchangeable lenses. In five years you could buy a new camera body with better electronics to take faster pictures, but good glass will still be bending light exactly the same.

thcrozier
26th Jan 2014, 19:55
Shaggy:

I misspoke in my general comment about Lumix above.

Bottom line and without going into the physics of it all, you need a camera with a faster lens. That means something in the range of f1.4 to f2. The notation might simply read "1:1.4 - 1:2", something like that. The second number in the 1:x.x notation is usually, but not always, the square root of 2 raised to an integer. The lower that number, the faster the lens, and the more it will allow you to achieve the "isolation" effect you like.

I see that there are indeed compact cameras nowadays with such lenses which are priced in the neighborhood of $300 to $400 U.S. and that Lumix has one.

Since this effect is obviously important to you, I suggest making sure whatever you buy has an "Aperature Priority" mode and the apereture is easily adjustable. That way you will quickly be able to obtain the desired degree of isolation.

Best,
Tom

mixture
26th Jan 2014, 21:05
I need a camera that's easily and unobtrusively carried around, and which gives good results.

Well that's great, and I've no problem with that. You just need to understand the limitations of your equipment.

Many things in photography you can work around.... others such as using aperture to achieve a blurred background, there's absolutely nothing you can do if you've got the wrong kit since its the fundamental principles of light.

I see that there are indeed compact cameras nowadays with such lenses which are priced in the neighborhood of $300 to $400 U.S. and that Lumix has one.

Beware though, these are probably variable aperture, i.e. not fixed throughout focal length.

Shaggy Sheep Driver
26th Jan 2014, 21:19
I think a distillation of this is (as Mixture says) you either put up with the limitations of a small and easily carried camera, or you lug around a bag of 'stuff' for a camera that can do narrow DOF.

I have no problem with budget, and would pay more than the price of a DSLR for a camera of G12 proportions that does narrow DOF. But physics don't allow it!

thcrozier
26th Jan 2014, 21:37
That's correct, they seem to range from 1.4 to about 2.3 depending on zoom.

chksix
26th Jan 2014, 22:01
I still have my Minolta f2.8 80-200 zoom. Not cheap at the time but nice. It didn't have enough reach for good aerial display photography, the planes were still specs in the sky at 200. Great pics of the static displays though.

Pelikal
27th Jan 2014, 18:30
Shaggy,

I had a little play with your pic in PShop if you don't mind:

http://i1100.photobucket.com/albums/g412/RobJHP/Bellerophon/Variation3_zps99d997b1.jpg (http://s1100.photobucket.com/user/RobJHP/media/Bellerophon/Variation3_zps99d997b1.jpg.html)

I tried a more extreme blurring on the foreground and background but it really looked artificial. I can't help feeling even this fairly moderate dabble looks odd. To me, it looks like a well made model! Maybe the shot is lacking the driver.

I've created a number of paths and masks which I can adjust independently. The tree/shrub area has 3 masks working at different planes. I can blur these at will now the basic masks are in place. Same with the tracks in the foreground.

I too owned a Canon AE1 and still have an F1n. Currently limited to a Nikon Coolpix 4300 compact so I fully understand the frustration of not having the greater facility.

I guess a bit of Photoshoppery is sometimes required as mixture has hinted at although I suspect the result here is short of the mark.

Shaggy Sheep Driver
28th Jan 2014, 09:06
Thanks Pelikal, nice attempt but I can't be arsed messing about with PS. I just want to take pictures when I want to - I'm not primarily a photographer so don't want a bag full of gear to lug about or hours spent at the computer fiddling with digital software.

I'll just have to put up with the limitations of my otherwise excellent G12!

Pelikal
28th Jan 2014, 09:18
Shaggy, fair enough. I guess I was bored on Sunday and fancied a 'play' with something. I'll leave it at that!

Loose rivets
28th Jan 2014, 18:07
Not having an easy to carry camera cost me one of the most wondrous photos imaginable. Well, for a pilot. Norfolk on a beautiful early spring morning. Being told by Colt to look back behind me. A Spitfire, or was it a Hurricane, had formated on my rear quarter framed by the English countryside. Just stunning, and NO CAMERA.:ugh:

Shaggy Sheep Driver
28th Jan 2014, 18:36
For decades I used to carry my AE1 with 50mm lens in the Chipmunk, jammed down the right hand side of the seat with the 'body' case on (not the 'lid' part of the case which swung over the lens and clipped shut), and with the lens cap on.

It was easy to slide the canopy open to the first notch, grab the camera (removing the lens cap) and take the picture through the gap twixt canopy and windscreen (the Chippy could be flown for short periods quite satisfactorily with one's feet only, even in a steepish turn though none too accurately ball-wise!).

The 'body case' of my AE1 carries the scars and scratches from Chippy cockpit metalwork to this day (as does that lens cap!).

Loose rivets
4th Feb 2014, 04:37
Well, the adapter turned up from Hong Kong, but no sign of the macro device. For the first time in years I recorded the photons coming out of my Pentax 1:1.4 lens. It wouldn't focus to infinity and I suddenly realized the ring was moving the lens further out even before an extender had been fitted. Mmmm . . . is it because I only paid $5 delivered, or are they all like that?

But it matters not. I got it for closeups so it's heading in the right direction. I had wondered why I'd seen it suggested using that lens for portrait work.

Are there adapters that bring the lens close, or does one need glass in the adapter to achieve that?

Bushfiva
4th Feb 2014, 05:22
Since you're light on details, I'm guessing. If it's an adapter with no glass element in it, then you'll lose infinity. If it's got a glass correction element in it, you'll keep infinity. E&EO, YMMV, no warranty implied.

Loose rivets
4th Feb 2014, 07:44
Yes, it really was a Doh! moment. But as I said, it's in the right direction. In the ones fitted with a lens, I guess you'd have to pay quite a lot for a decent lens. There's no point in having a nice bit of kit like my Super Takumar and then putting a plastic lens behind it.

The spacers are still making their way across China, I should think. :ugh:


http://img.photobucket.com/albums/v703/walnaze/0%20Seiko/7A%20Time%20no%20go/7A38nogo_zps6df7632c.

http://img.photobucket.com/albums/v703/walnaze/0%20Seiko/7A%20Time%20no%20go/7A38nogo_zps6df7632c.jpg (http://smg.photobucket.com/user/walnaze/media/0%20Seiko/7A%20Time%20no%20go/7A38nogo_zps6df7632c.jpg.html)jpg

Bushfiva
8th Feb 2014, 06:25
You know, if you don't tell anyone about it, you can make spacers out of bog roll tubes and tape. You can also get two cheapo lens filters, remove the glass, glue them together to make an adapter that will let you screw two lenses together, objective to objective. That also works just fine.It would only take you an afternoon to muck around with such stuff. That also works just fine.


But personally, I'm a point-what-you've-got-at-the-thing-and-click-the-button person, which works most of the time.


Many scanners, especially the older/more expensive ones with the folded optical path rather than CIS, do a good job too.