|
Forum: General Photography
02-01-2019, 05:32 PM
|
| |
BigMackCam
Somewhat off topic but right up your original post.
NYT Production Assistant John Kurdewan Recounts Bill Cunningham
My "42" shirt is in the wash, "Thanks for all the fish" and My main desktop PC is named "Deep Thought" along with Distant-Thought. O-Distant-thought, Pure-though, Old-Thought and Tablet-Thought.
|
|
Forum: General Photography
02-01-2019, 04:08 PM
|
| |
My 2¢.
However, if they ask "Why "more" ore "less" of your images appear to be in focus - How did you get that?" Then you can begin a discussion/education of DOF. Still no reason to bring up Equivalence.
---------- Post added 02-01-19 at 03:23 PM ----------
Or better yet, ask the "beginner" why in the name of heaven are you going to "upgrading" to 35mm format? Again, why all the hastle about equivalence. "Beginners" don't care about DOF or FOV all that much.
If they have an APS-C camera and are "upgrading" (a questionable term to begin with) you might tell them that they will have to get a new set of lenses because their current APS-C lenses will vignette. If you state that "You will have to rely on the cameras compatibility mode" then you are obligated to tell them (in the Pentax world) that they will take a significant hit in megapixels. (I.E. K-1xx in cropped mode => around 15Mpx < K-3II, KP, K-70 etc. 24Mpx) 24-15 = 9 Mpx loss or more than a *ist Ds) A K-1xx in cropped mode has fewer Mpx than a K-20D.
|
|
Forum: General Photography
02-01-2019, 04:03 PM
|
| |
OK, you made me do it. From: A Practical Guide to Using Film Characteristic Curves | Film Shooters Collective Dude, film is logarithmic, digital is linear.
The simple reciprocity seen in digital image sensors is the straight line section.
And (I can't really believe that I am doing this) to quote KR:
"The biggest reason the results look different is the highlights. We're used to the way film looks. It overloads gracefully when things get too light or wash out. This mimics our eye far better than digital. Digital's weak point is that highlights abruptly clip and look horrible as soon as anything hits white. Unlike film there is no gradual overload to white. Digital cameras' characteristic curve heads straight to 255 white and just crashes into the wall. it's the same with video versus motion picture film. If any broad area like a forehead is overexposed your image looks like crap on digital. This effect is similar on cheap pocket cameras, my expensive Nikon D200 and $250,000 professional digital cinema cameras."
https://www.kenrockwell.com/tech/filmdig.htm
And Wikipedia:
File:Foto-wiki-Balance-Film-Speed.svg - Wikimedia Commons
https://en.wikipedia.org/wiki/Photographic_film |
|
Forum: General Photography
02-01-2019, 12:40 AM
|
| |
No No No.....
Film response is logarithmic, digital is linear. Please do not conflate terms what you want to use with terms that are well understood and well defined in the discipline. Please read about "toe" and "shoulder" and the logarithmic nature of film. Reciprocity in film is NOT the same as the linear response found in digital. When I tried to shoot film for astrophotography through my telescope hitting the shoulder of the film caused issues that pale in comparison to what is possible in digital. You might as well as said that you are now talking about the exposure triangle as "entanglement" with some grand unified theory of "EQUIVALANCE".
You just can not be expected to redefine well known terminology to fit your desires. Rant over. Now back discussing the confusion of the moment.
|
|
Forum: General Photography
01-31-2019, 07:00 PM
|
| |
Be careful here, to some of us old guys reciprocity, eg. reciprocity failure, has a well know definition from back in the film days. I beg you, don't start using terms that mean one thing in photography to describe something completely unrelated.
"In photography reciprocity is the inverse relationship between the intensity and duration of light that determines the reaction of light-sensitive material. Within a normal exposure range for film stock, for example, the reciprocity law states that the film response will be determined by the total exposure, defined as intensity × time. Therefore, the same response (for example, the optical density of the developed film) can result from reducing duration and increasing light intensity, and vice versa.
The reciprocal relationship is assumed in most sensitometry, for example when measuring a Hurter and Driffield curve (optical density versus logarithm of total exposure) for a photographic emulsion. Total exposure of the film or sensor, the product of focal-plane illuminance times exposure time, is measured in lux seconds."
Reciprocity (photography) - Wikipedia
---------- Post added 01-31-19 at 06:18 PM ----------
This would be a really bad idea. Why abandon one of the most basic assumptions in photography? Just to support the background of equivalence? No. Just use equivalence as a stand in for FOV.
Sorry, but I do not understand the need to constantly compare APS-C to 35mm format. For instance I carry three lenses around on vacation:
A 8mm Ultrawide.
The 18-50mm Zoom.
The 50-135 Zoom.
So if I were using a 35 mm camera it would end up being three lenses.
A 12mm wide angle.
A 27-75 Zoom.
A 75-202 Zoom.
When I was carrying my 35mm kit.
A 28mm wide angle
A 55mm "normal lens"
A 135mm telephoto.
With my current set of three lenses I can cover every focal length from 18mm - 135mm or "equivalent" 27mm - 200mm. Do I think about what the equivalent focal lengths are? No No No …. I look through the viewfinder to find the framing that I want and if necessary swap out the lens to match what I want to shoot and shoot. In my film days, I carried three cameras, now I carry one body and three lenses. Why all the fuss? I guess I just do not get it.
|
|
Forum: General Photography
01-30-2019, 02:36 PM
|
| |
| |
|
Forum: General Photography
01-29-2019, 07:33 PM
|
| |
I looked at the thread and basically agree with the findings there. This is the appropriate use of equivalence. Once you have made the calculations - move on.
|
|
Forum: General Photography
01-29-2019, 06:22 PM
|
| |
Put me in Kunzite's camp. If I wanted to see if the I could better understand a photographer's work just why in the name of heaven would I have to replicate his lens and aperture to advance my understanding? Did you limit yourself to the ASA/ISO of the film he used? Did you zone focus? Did you set your camera to all manual mode? Did you stop for 3 minutes after taking 24-36 exposures to simulate changing film?
Since you got your self convinced that you were going to get something out of this here are the steps.
Figure out what lens focal length and aperture you need on your APS-C camera using the dreaded equivalence methods we have used here.Get a 24mm lens or gaffer tape your zoom to the appropriate focal length. Set your fstop to the calculated value. Set your camera to manual mode.
Set your camera to disable AF.
Set your camera's ISO to the appropriate value.
Set your camera to for manual exposure to select the shutter speed (green button comes to mind but the match needle of a FM2 would be quicker).
Set yourself a limit to how many images you take (24 or 36) before waiting three minutes before taking more images.
Turn off instant review.
While you are out and about - NO CHIMPING
Get up off of your vertical smile and get out there and take the pictures.
Here is one of the more important things ----- DO NOT LOOK AT THE IMAGES FOR A MINIMUM OF 24 HOURS.
Now that scenario will give you a better understanding of Bill's working conditions.
The next questions are:
How important is "equivalence" ---- answer the first two steps - easy peeasy - background noise.
Did you learn anything ---- You would learn that manual cameras and street photography "back in the day" were not easy. Film has its issues, single ISO/ASA/Din, limited number of images, time it takes to see the images etc.
Now you might just end up appreciating Bill's work even more because you have just experienced (as close as you could) the conditions of the pre-digital/auto camera days. Now you have a better appreciation of Bill's skills and technique that he used to create a large body of work. Some of us have used manual 35mm cameras to do this in the past - it ain't a big deal. You will also find that most of us do not want to go back to this way of working. Now I have been using automatic 35mm exposure cameras since the mid 70's and for most work I would not really want to go back to the match needle (in my case match LED's) days. We have moved on.
Now here is my point about your quest. You have repeatedly brought up this project as a, for the lack of a better word, "reason" for the use of equivalence. While equivalence is important, to you, to emulate the technical requirement, the part equivalence played is trivial. Your experience did not come to fruition because of equivalence, equivalence is a tool you used to replicate part of the technical aspects of the camera. Bill was not the camera, lens, FOV, ISO, sensor format or what he held in his hand. Of the ten points I outlined above, equivalence is step one, end of story.
I still do not understand the need to describe how to shoot the same scene, with the same FOV and DOF is so important. Just look through the viewfinder on your camera and take the shot the way "you" want too. If you have enough money that you can finance a new camera/lenses and you want to replicate your current body and lenses. Then use equivalence to give you a range of field of view, or Focal Lengths, you need to purchase. Equivalence is a tool, with a very narrow application. Use it when you need to, but please don't go off and start describing how you "have" to use it to get anything done.
---------- Post added 01-29-19 at 05:27 PM ----------
-snarkon
But rear engine cars can be a better solution in some situations i.e. Porsche, Ferrari, Lamborghini, Corvair. etc.
-snarkoff
;)
|
|
Forum: General Photography
01-29-2019, 12:59 AM
|
| |
I agree, but your description is not what is being used by quite a few "experts" out there. There are many people who have implied that the focal length changes as you take a 35mm lens and put it on a ASP-C body. There are even videos suggesting that camera manufactures are lying about the focal length range on their zooms for non 35mm cameras.
No one has suggested that shutter speed falls under the scope of this discussion of equivalence. Making off the wall comments is one thing, but let's not add to the confusion going on here.
Now back to your regular station.
|
|
Forum: General Photography
01-28-2019, 11:01 PM
|
| |
Say What? Wait ---- Wut?
Shutter speed is well understood to mean how long the shutter is "open" to the sensor. Focal plane shutters (at least in the Pentax world) are a moving slit at anything over 180th of a second. However, to the sensor, the shutter allows light to hit it for the "shutter speed" period of time.
Man, you are really overthinking this.
|
|
Forum: General Photography
01-28-2019, 07:05 PM
|
| |
The lens is the easy part Bower 24mm f/1.4 Wide-Angle Lens for Pentax SLY2414P B&H Photo Manual focus too. Although I doubt it very much that his 35mm was anywhere near f1.4.
(Yes I used the old 35mm / 1.5 to get the focal length. I could have gone out to B&H and looked up the FOV of the appropriate lens too)
In my case, I would take out my old 18-55mm kit lens or my 16-50mm lens and taped the zoom to around 24mm (I could have taken a few images and checked the EXIF information to see how close I got to it.
Set the focal length, you have the information for the DOF - although you might want to play with that to get closer to what you think you might need.
From DOF Master
35mm f/8 focus at 10 feet near focus 6.28 feet far focus 24.3
24mm APS-C f/8 focus at 10 feet near focus 5.44 feet, far focus 62.9
24mm APS-C f/5.6 focus at 10 feet near focus 6.27 feet, far focus 24.5
The lens above is manual focus so no having to choose focus points. The nice thing about digital is that you can modify the ISO/Shutter speed as you need. Bill was using film - so he was stuck, but I fully suspect he was aware of how to set his camera to meet the situation/conditions.
Then, I would sit down with you and ask what is the purpose of exactly replicating someone else's local length, fstop, shutter speed and ISO? Bill's style is what he developed over the years and I am sure that he changed things up as the situations changed. It just seems to me that copying some ones physical settings is not gaining you anything. Copying the style is one thing, trying to copy the intent is another - equipment does not matter.
|
|
Forum: General Photography
01-28-2019, 04:11 PM
|
| |
I have 3/4 of a case of Costco microwave popcorn in the pantry. :lol:
---------- Post added 01-28-19 at 03:21 PM ----------
I would only tell them the obvious, equivalence was created to help 35mm film shooters understand why their old lenses did not work on their smaller sensor digital cameras. Now, if a person has bought a point and shoot and upgrades, or wants to upgrade, their camera to a 35mm format camera, then I would start to explain the differences that the sensor/body/lens size will be so dramatically different. Equivalence would be a tool to use to explain to the user that a 10-300mm zoom on their point and shoot is going to be Huge, Heavy and Expensive on their 35mm camera.
|
|
Forum: General Photography
01-28-2019, 03:59 PM
|
| |
---------- Post added 01-28-19 at 03:00 PM ----------
I disagree most vehemently. When I was first starting out in photography I "learned" by looking at Look, Life, National Geographic and newspapers. I read books by multiple authors to gain insights on technique. When I finally got to a point where I bought my own camera, it was extremely limited it what I could do with it. It was a capture needle (powered by what passed as a solar cell in those days - no battery) and when you set it to "manual" on the shutter it was a 1/30th of a second.
My father had some older cameras he used in his youth, a FothFlex 2.25x2.25, a speed graphic and his fathers old Kodak bellows fold out camera. The first camera I used extensively, learning how to develop film and make contact prints, way my mom's Brownie Box camera. You don't learn the subtleties of technique when you have a 1/30 of a second and two holes to select for aperture. ASA/ISO/Din - not needed, you either came out with pictures or they were black, no such thing as flash. Later in his life, after we built the darkroom, the bought his Calumet 4x5, found a Speed Graphic and bought a Mamiya SLR that did not have interchangeable lenses. He finally ended up with a Pentax K1000.
While in high school, I used the schools Yashica Flex and my rangefinder (see above) and started using a strobe flash that I received for my 16th birthday. I convinced my father to purchase the Time-Life Series on Photography and read every volume multiple times. I learned a great deal from books and looking at images from the masters listed in the that series.
And the main point of this long winded discussion? I never, ever, used equivalence to decide on how I shot or shoot an image. I do understand how different "angle" lenses work. One of my most fun lenses I use is the Bower 8mm Ultrawide on my Pentax bodies that has a 167 deg field of view.
If a beginner comes to me, and they have, and asks me how to get a particular "look", I have them pick up their camera and look through the viewfinder. I show them that by physically moving they can change "the look" of what they see. If they need a true wide angle lens then I suggest that they get a lens that covers the area they want to shoot. If they ask about equivalence, I take a deep breath and explain to them why they should not care about equivalence when using their point and shoot. Just zoom/move to a spot that meets the requirements to get the image.
|
|
Forum: General Photography
01-28-2019, 03:24 PM
|
| |
I agree - see my edit to post #300.
And to add more fuel to the fire think about what Pentax would have to do with this.
From B&H
Pentax Normal SMCP-FA 50mm f1.4 (on 35mm) FOV 47 deg
From Exiftool on my last photo jaunt.
Pentax Normal SMCP-FA 50mm f.14 (On APS-C - a K-3II to be exact) [Composite] Field Of View : 27.0 deg
It is a really bad idea to include FOV, but it is more descriptive of what is going on. If only the "full frame" people had used the correct term in the first place.
|
|
Forum: General Photography
01-27-2019, 11:49 PM
|
| |
Fogel 70
I said it would make for a bad story title, but I think in the context of shooting portraits, it would be more interesting to delve into the idea as to why the field of view provided by a 85mm on 35mm is "the" choice. The article is part of the problem with equivalence, a 35mm lens on a APS-C is equivalent in FOV only to a 85mm on a 35mm camera but it suggest that if you want a 85mm on APS-C you have to get a 56mm, suggesting that the focal length changes when you change the sensor size. The article would/is confusing to New or even some seasoned users. I gave an attempt to rectify the situation and in you eyes it failed, so be it.
However don't fall into the trap of over thinking it too much. I hope you are not reading into my comments some underlying hidden agenda. My comments were just that, don't take them so seriously.
Edit:
From B&H specs
Fuji 56mm FOV 28.5° on ASP-C
Rokinon 85mm FOV 28.3° on 35mm
So yes, if one wants to be pedantic you could start throwing out FOV in degrees to add to the confusion.
Doing this would be a really bad idea.
|
|
Forum: General Photography
01-27-2019, 05:55 PM
|
| |
Just because Fuji says this is not a reason to suggest to people that 56mm on APS-C is "really" 85mm. Both the article and Fuji could have said something along the lines.
Given that our 56mm lens provides the same Field of View as a 85mm on full frame …. (note: I hate the usage of this term)
The article could have been titled Our Four Three Favorite 85mm Portrait Lenses Under $1,000 and a APS-C 85mm FOV lens for Thrifty Shooters.
Not a very good title, but it would not be as confusing to some as reading the first part where the article is about 85mm lenses and they start off with a 56mm lens.
|
|
Forum: General Photography
01-27-2019, 05:26 PM
|
| |
No, not at all. I used shallow DOF when I wanted to get the effect I wanted and made the appropriate changes to get what I wanted.
Back in the day, I very rarely used anything above ASA 400 and I used ASA 400 grudgingly. (Kodachrome 25/64, Fujichrome 100, Ecktachrome 160, Panatomic-X 125 and Tri-x 400) If I wanted a "thin" DOF (given that I only had one "fast" lens) I simply used a higher shutter speed (max 1/2000 second). If I wanted a "thin" DOF in low light, I used a longer shutter speed, a tripod or desktop tripod or perhaps added flash. My point is that when Dartmoor Dave states "The idea of shallow depth of field being a desirable (even essential) thing is a digital-era invention" is incorrect from my perspective. I have been using "thin" DOF to my advantage (given that I had the camera/lenses that allowed me that control) since I bought my first SLR (Exa Dresden-Ihagee) in the late 60's. A "thin" DOF has been a desirable function in photography that is much older than digital. |
|
Forum: General Photography
01-27-2019, 05:13 PM
|
| |
I don't use equivalence at all really.
When I switched to digital it was at a NG week long workshop. I was the only person to shoot both film (Fujica ST-801) and digital (Pentax *ist Ds) and I never thought about equivalence at all. I did learn about back button focus and AdobeRGB color space but did I fuss and fume about equivalence? Nope - not at all.
What I did was look through the viewfinder to compose the image I was about to take. I have learned over the years that zooms, while purists my disagree, are way more convenient that primes when out taking images. Now don't jump all over me about how primes are better than zooms, my film 35mm SLR (three bodies) lens selection has one zoom and three (four if I swap out Pentax adapter on it) primes. My DSLR (three bodies all APS-C) lens selection is three primes and four zooms. When I go on long vacations I take my two zooms and one prime. I don't really give a second thought about equivalence at all. I am not interested in replicating any given shot using my 35mm SLR's for the practical reason that my film cameras are usually back home on another continent.
Back when I was active in a photo club, we really didn't talk about equivalence. The members of the club used everything from the so called full frame (it galls me to use that term) to point and shoots that had 2mp sensors. When asked how someone could replicate one of my, or anyone else's, images I would always ask "Why in the name of heaven would you want to replicate this image. Go to place where I took this one and create one that has your interpretation". I also suggested that the members go out and push their equipment's envelope to understand what the potential is. Evidently my ideas did not take hold when the club shut down due to no one showing up, other than me, and it became a run of what I shot since the last meeting.
What I find maddening about the use of equivalence is that for some reason people who have never shot 35mm film are expected to be able to understand how 35mm film cameras functioned. For heavens sake, look through the viewfinder and adjust what you see to get what you want. If you do not see what you want, then move around until you do see it and take a picture.
One last point - when using a SLR/DSLR if you see the picture that you really really want, you missed it. The picture is taken with the viewfinder is blacked out.
|
|
Forum: General Photography
01-27-2019, 04:18 PM
|
| |
My -snarkon -snarkoff tags indicate that the remarks are somewhat satirical. In general, I think that you would be hard pressed to find a salesperson that would actually like to sell you a Pentax camera system in today's market place. Yes, you could use another manufactures bodies/sensor size to get the point across, but I think using Pentax in this context is just not realistic. A commission salesperson will try to sell the most expensive item, regardless of the brand.
---------- Post added 01-27-19 at 03:23 PM ----------
OK then.
---------- Post added 01-27-19 at 03:27 PM ----------
You did not see the line highlighted section include the line above from Dartmoor Dave. DOF in my experience was a method to isolate portions of the image to emphasis composition and subject isolation looonnnngggg before the digital era. Please read the entire section I selected not the one you highlighted in your post #200
|
|
Forum: General Photography
01-26-2019, 05:26 PM
|
| |
With 55+ years of photographic experience I have to disagree here. I always used the DOF scales on my lenses to control "what appeared to be in focus" as a matter of intent. When switching to digital, the most frustrating thing was/is the removal of DOF scales from lenses. Remember, back in the film days we did not have the ability to change ISO on the fly, we were stuck with the ISO, or for us really old guys ASA/Din, cooked into the emulsion. I used the DOF scales to define those parts of the image that were "in focus". In fact its very easy to use hyperfocal focusing with them, where it is a real pain in the brain/backside to do it on digital lenses. Even the distance scale is pretty much dummied down on digital lenses, which is just plain wrong.
|
|
Forum: General Photography
01-26-2019, 05:09 PM
|
| |
"When used on Fujifilm’s APS-C based cameras, the 56mm f1.2 will have the equivalent focal length of an 85mm lens on a Full Frame camera."
https://www.thephoblographer.com/2019/01/19/four-85mm-portrait-lenses-under-...ou-speechless/
Happens all the time. Very confusing to a first timer i.e. the conflation between FOV and Focal length. This is an article on 85mm lenses and they are taking about a 56mm physical lens.
Look in the comments and see the reaction to mine. "Stop it" is my favorite with "This is not a physics site". Good Grief.
|
|
Forum: General Photography
01-26-2019, 04:55 PM
|
| |
-snarkon
The only problem I see here is that the camera salesperson (see what I did there?) would most likely not push the Pentax cameras. In my limited experience, the sales people work on commission, they would push Nikon/Canon/Sony rather than Pentax because the salesperson would make more money off the sale.
-snarkoff This happened with my wife back in the 80's while I was going to grad school. She worked at a computer outlet and was told to push customers to the IBM rather than the TI-Pro because the IBM was more expensive. The TI-Pro, that she got for me, was faster, had better graphics (independent text and graphics layers and 256 colors as opposed to the IBM 8), a bigger power supply and on of the best keyboard layouts around.
Salespeople will sell you the most expensive thing they can - because they get more money when they do.
|
|
Forum: General Photography
01-26-2019, 04:34 PM
|
| |
| |
|
Forum: General Photography
01-26-2019, 03:46 PM
|
| |
Fixed That For You.
---------- Post added 01-26-19 at 02:56 PM ----------
It is interesting that some people will push "total light' as if the lens has some magical essence that will allow more light through it when the sensor size changes. My FA 50mm f1.4 lets in as much light as it is designed to do. When I had my, stolen, FA 50mm f1.4 on my SF-1 it allowed the same amount of "total light" through as it did when placed on my K10D. I guess the lens did not get the memo.
|
