Stenis
(Sten-Åke Sändh (Sony, Win 11, PL 6, CO 16, PM Plus 6, XnView))
21
I think the autofocus I now have in my A7IV does it much better than I should achive with manual focus. Before in the evil DSLR-days of mine with constant focusing problems I used what still is called Direct Manual Focus or DMF. Then the system first used AF, locked once and then released to let the user focus manually if needed. Worked even with Minoltas AF generation one lenses from the eighties that were screw driven since there were a mechanical clutch in the KonicaMinolta D7d and Sonys DSLR- and SLT-cameras.
Today I never need to use DMF because the system is so accurate that focusing nowadays has become close to a none issue. I hardly think of it anymore and I think the Canon R-users must feel exactly the same. Last years AF has almost gone through a paradigm shift when it comes to usability and accuracy. Of the same reason I rarely take more than one or two images of a motif because I now know the focus is there were I intended to put it.
There are tests of for example A1 and R5 that shows an hitrate of around 95% tracking moving targets. That’s were the best AF-systems are now. Using manual focus will certainly give you fewer keepers and probably also quite a few lost images too. I’m also pretty sure the ones waiting for Nikon’s new Z9 will get a fantastic AF-system too.
It’s been an interesting evening. I’ve been reading so much my head is spinning, but I think I found out some explanations for what everyone has been discussing, all of which led to an article by Ken Rockwell who posted a write-up the matches what several of you have said, but puts it into words that I can appreciate.
Reading between the lines, (I almost typed “lies”), it comes down to doing all sorts of testing to learn what the camera gear can do, and what the limitations are, and then to use the camera within those limitations to get it to do the best it is capable of in a way that improves the image.
I was researching my 1960’s LEICA 35mm SUMMILUX 35mm lens (Summilux = f/1.4 max aperture), is an old lens with limitations, but when stopped down to around f/8, it can get results comparable to what I could get with Leica’s very lates ASPH lenses that sell for over $8000. For me, this is a whole different way of looking at things. I suspect that all of you will appreciate Ken’s article on sharpness, regardless of what you think of Ken Rockwell. If any of you are interested, here’s what Ken had to say about my old 35mm Summilux: https://www.kenrockwell.com/leica/35mm-f14.htm
When I create a “landscape photo” (generic term, could be a boat, or a locomotive, or a machine, or a skyline) I usually want everything as sharp as possible. I guess this means using camera gear that is capable of doing this, then using the proper settings for the camera gear, and finally using settings in PhotoLab to properly bring out that “sharpness”, or whatever qualities I’m interested in.
I’ll also admit that two years ago, I thought I could have everything I wanted just by using DxO ClearView Plus which magically eliminated all the “haze” that was hiding my image. Then people beat it into my head that I was ruining the image, and eventually I saw what they meant. Oh well, live and learn…
I’m getting tired, and am about to turn off my computer and go to sleep. The thought that I don’t know how to properly express, is that sharpness is just one of the tools I’d like to use to emphasize the part of an image I think is important, but maybe it’s just as important to use the lack of sharpness to de-emphasize those parts of my image that just become distractions when they are tack sharp. I think this means that I need to learn how to USE depth of field to improve my image, and find out if PhotoLab has tools that I can use to “decrease” unimportant things from distracting viewers, so they see what I would like them to see.
My understanding is that larger sensors have a comparatively shallower depth of field for a given lens, though perhaps this is negated somewhat by the ‘effective’ focal distance of a smaller sensor? If those cancel out then sensor size wouldn’t matter. If not, your depth of field is going to be shallower, potentially decreasing the sharpness the photographer wants.
More pixels, in a given sensor size, means more theoretical resolving power (assuming a decent lens), but also more noise and, arguably, more relative area given over to 'inter-pixel dead space", both an enemy to sharpness I would think. Again, of course, this can be negated by newer manufacturing processes.
All of which is to say, it depends on so many factors as to how “sharp” a given scene can be captured, in which case it comes down to your other points, with whatever equipment you have on hand.
Hi
I don’t disagree, by automatic af i meant the mode the camera is choosing the focus points usually it will focus on the nearest object (don’t know the name of this mode). Personnally i use one zone focus. I have set a button to have magnifier to ×10 and focus. I can also force af to go to nearest object if needed.
Animal/human/train/car af focus are quite handy (buy an hybrid ;-), for moving subjects indeed. The hit rate for moving subjects with automatic tracking is much higher than what i would achieve. However i had for some time a A7 3 and focus for portrait was usually on eyelashes for close up with low focal , not on eye ball.
Maybe the conclusion could be : know your gear and don’t shoot automatic if you don’t know the limitations. If you get out of focus pics, try to understand why, the camera is not always to be blamed…
There are several arguments in favour of better cameras :
if the sensor has more pixels, the right comparison is at the same size of pictures and not as the same size of pixels ; at the same size of pictures Sony A7RIV (62 MPix) is better than A7RII (45 Mix) ; I had the two ones ; this is also confirmed by DxoMarks that have tested the same with lenses with several cameras ; my 24-240 was rated higher wit A7IV
backlit sensors are much better in low light.
But those two points are more expensive.
The shallower depth of field makes the focused area sharper in comparison with non focused areas.
And you are absolutely right. The key is to minimise the compromise.
Which explains why a 20ft high photo on the walls of Dublin airport had visible pixels about 6" square when I walked past it at 2ft. You’d have thought, with all the money airports make, they could have, at least, employed a photographer who knew what they were doing
Absolutely. Things have changed with digital sensors and the (unrealistic) expectations of photographers using high magnification editing tools.
This is one amazing article that you (or anyone else) need to instil in your brain. I especially love the bit that says it is almost exclusively men that pixel-peep
Strictly, a landscape photo is not the same as a photo of a locomotive or a machine - those are more “industrial portraits”.
And this is where all the camera-related stuff starts to merge into the PL-related stuff, which this thread should be about.
Absolutely
This is never going to be as successful as getting it right in the camera.
You mentioned “zone focus”, which is an automatism where you let the camera try and work out what it thinks you want sharp - which can never be the same as choosing your point of focus and accounting for how much DoF you are going to need to make everything you want acceptable sharp.
I mean one single area zone focus : on my hybrid, you can change the size of the single area from around half the size of the sensor (advantage could be that you force the camera to search a subject in this area only, but as you say, you rely on the camera to determine what is to be in focus) to a focus “point” (which are not points but zones) : i have 225.
I really well know that hybrids don’t meet everyone’s expectations, so i am not willing to launch a DSLr/hybrid war
Focus peaking then shows what is supposed to be in focus. Disturbing at beginning (and will give headaches to OVF lovers) but performing well on my gear.
So translation in the DSLr world is as you say i suppose.
I have also pinpoint mode, but in my experience, on Panasonic (contrast detection only…), it is sometimes not reliable. Using the magnifier with a single “point/zone” is more efficient (for stills).
In this post, I want to try and define what “sharp” means, how to achieve it in camera and how to to emulate it in PL
A lot of my understanding on this subject is based on the writings of George Douvos, the author of TrueDoF-Pro - a calculator for DoF that takes diffraction into account.
“In the beginning” the circle of confusion, which most DoF calculators are based on was calculated as being d/1500 (the diagonal of the film/sensor divided by 1500), which for 35mm full frame equates to 29µm - usually rounded up to 30µm on most calculators.
This represents the maximum dot size that will not be perceived as blurred when an image is viewed at an appropriate viewing distance.
This is fine, as long as you don’t intend to print at anything bigger than 10" x 8" to be viewed at arm’s length. And it would still be fine as long as we don’t look at an image on a computer screen at an equivalent scaled size.
But how many of us are satisfied with editing our pictures for sharpness at that scale?
Here is a screenshot of my 27" monitor with PL5 editing a picture that measures 10" across on the screen…
According to the 30µm CoC rule, this image is acceptably sharp from edge to edge, and I defy anyone to say otherwise.
The problems start when we zoom into an image and judge sharpness based on some incredible zoom factor, well beyond the accepted viewing size and distance for a CoC of 30µm.
The screenshot I shared is taken at 14% zoom but what size print does viewing the image at 100% zoom give?
A 27" Apple display has a resolution of 110ppi so, taking an image from my D850, with a width of 8256 pixels, that would equate to a print 6ft 3in wide!!! And you are wondering why it doesn’t look sharp when viewed at 2ft from the screen? Even Mike’s 24Mpx D750 yields an effective print size of 5ft 6in.
I want to print images at around 3ft wide and, for printing, I need to produce a file at 240ppi to get an acceptable print quality. This means that the maximum print size I can achieve, without resizing, is going to be 34" along the long edge - which is near as darned it good enough.
All this means that, in order to judge sharpness on my 110ppi screen, for a print at 240ppi, I need to set the zoom to 46% and to view the screen from 43" away. The only problem with that zoom factor is that a lot of PL5’s adjustments don’t show correctly, so you would need to sit further away from the screen at 75% zoom
So, why, when many are only ever producing JPEGs for on-screen viewing, do we judge sharpness at 100-200% zoom from 2ft (or less) from the screen?
Part 2 to follow after I have been for a walk in preparation for watching the Six Nations Rugby matches this afternoon/evening.
I know that my PhotoLab 5 has “tools” about “focus”.
I have happily ignored these adjustments for two years now, as nobody in the forum has been saying much about them, and I’ve been concentrating on things I’ve learned in this forum to be important.
Would it be useful to discuss these tools, and how they may help, or hurt, our image editing?
(When you write “hybrid”, are you referring to the cameras that in the USA are called “mirrorless”, meaning the photographer sees a digital view of what is being photographed, instead of an “optical” view? If not, I’m confused as to what you mean.)
The Focusing Distance tool is only for those cameras that support adjusting such - if it is disabled, it’s not necessary. The Blur is a creative tool, not a corrective one.
Excellent question, “why” am I doing exactly what you describe? I highly doubt that I will be printing at 100% and getting a five foot wide print, but on the other hand, I often crop my images. Yes, I almost always examine my images at a normal size, and then check at 100%. From what you’ve written, maybe I ought to be viewing them at 50% size which is easy to do in PhotoLab 5.
First thing I did when I woke up was to mount my M10 on a tripod, with the 35mm Summilux mounted, set to f/8 and take photos of a building opposite my building, and one of the Miami skyline. The skyline photos looked “hazy”, but when I looked outdoors again, being more critical, the skyline WAS hazy. Today is not a good day for that kind of test. So, I instead looked at the photo of the building opposite mine, and excluding the extreme edges of the image, it is as sharp as I had hoped. Knowing I’ve been using this lens since the 1960’s, and that it has never been serviced, I might want to send it off to my friend Don at DAG Cameras, and let him go through it. All of which leaves me undecided about the Voigtlander lens I’ve been considering.
To put what you wrote in another way, supposed I had a large glass jar filled with coins, and I wonder about how much $$ it contains. I don’t need to find out it has $23 dollars and 39 cents in the jar - all I really need to know is it has around $20 worth of coins.
Or, in camera terms, I don’t know exactly what the resolution of my old lens is in the center and at the edges, all I really need to know is whether the lens is sharp enough for me to keep using, or should I get it adjusted or buy a replacement.
@Joanna - I already “know” what you just wrote, but only theoretically. My real question is whether a lens I own is appropriate for the types of photos I take, and how others get to view them. In the “factual world” this is obviously true. In the “emotional world” (my mind) I like to think that if I got really serious about a specific photo my camera gear can take, what are my limitations? There are times when in India I am asked to take a specific photo, which I know they will want to print at a huge size. So, do I need or want to be able to accomplish this for them? I would like to be able to do so, but there are limits as to how much $$ I would need to spend.
(The last time this happened, my go-to camera was a Fuji X100f, and I took two photos, which they combined into one larger photo. They were happy, and I was surprised at how well it all came out!)
The photographer who took the photos for the airport that you described - had he really understood all this, it might have been a real challenge, and his current photo gear might not have been capable of achieving the desired results… So, do we all want to be able to achieve this, if asked to do so?
When SLR cameras came out, there was usually a ground glass focusing screen, and a small “split image” area in the middle to help adjust focus on the manual focus lenses we used back then. Now with dSLR and auto focus, the viewfinder no longer has all the old tools, and I find it difficult to focus manually. Auto-focus makes it easy and fast.
There are new tools available - I haven’t used them on my Nikons, but on my M10 when I’m focusing with the Visoflex, there are focus aids that help me get the best focus.
Not sure what you meant by the “evil DSLR days”. How were they worse for you than the SLR days?
If we’re talking about sharpness, we also need to consider camera movement, as in how steadily we hold the camera, and how much it might move just from our applying pressure to the shutter release, along with what shutter speed we’re using. I suspect a lack of sharpness can be due to those reasons, more often than because of lens quality. A tripod and cable release is mandatory if we’re really going to get serious about sharpness.
Ah! So, you’ll be wanting the 2000mm f/0.95 super-zoom that Elon Musk must be designing to take photos from his yacht that is too large to get out of the shipyard without dismantling a historic bridge
Seriously though, this is where the weight over megapixels argument comes in and where I am so pleased that I chose the D850, even though it is heavier than some.
If your images are only destined for screen viewing, the best test is to put PL5 in “fit to screen” zoom and use PL5 in full screen mode. Not forgetting that you will need to use a zoom greater than 75% to assess the effectiveness of certain tools in PL5, but for that, all you need to do is sit back a bit further from the screen.
Can I help? Forget it, it’s not worth the money when you can simply optimise the lenses you already have.
Yesss!!!
Nah. If it ain’t broke don’t fix it
But then you have to ask yourself how often that happens and if you want to buy a D850 for just those few times. Or you could learn how to take multi-shot composite images on your D750 and assemble them in Affinity Photo.
So, you’ve answered your own question. Except using the D750 would have given more pixels to work with for each image.
Composite image of five shots taken on a Nikon D100 (6Mpx), ISO 400, 1/500 sec @ f/22, with a Nikon 28-200mm zoom at 80mm.
Using Genuine Fractals, This got printed by Calumet for their Liverpool store and, at nearly 14ft long, from its intended viewing distance of around 10ft, it was just stunning to look at.
Moral of the story - you don’t need expensive gear to make great images, jus the knowledge to make the best of what you have got.
Honestly Mike, you’ve already got more gear than you could ever use. What you need to do is concentrate on the D750 (with the lowest shutter count) only and how to get every type of photo you will ever need out of it.
If it had been my job, I would have use a 10" x 8" film camera - 10ft x 8ft print without blinking and a 40ft x 32ft print using Genuine Fractals.
Of course. And this is where you use a high megapixel camera with high ISO and PL5 DeepPRIME to enable higher shutter speeds. I’ve already mentioned that I regularly use 10,000 ISO for concerts and would happily go higher - simply because I absolutely know that PL5 can handle it.
Don’t forget, with VR, you can use a good couple of stops slower speed-wise. in theory, I should be using 1/400 sec for a 200mm focal length but, with VR, can get away with 1/100 sec much of the time.
This is something I haven’t spent enough time thinking about. for all my cameras, thanks to PL5 I can shoot at higher ISO speeds than I ever considered before. So, if I’m shooting at f/8 or f/10, using ISO 10,000 or so, in poor lighting, my shutter speed can get up high enough to mostly eliminate camera movement from being an issue.
So, let me ask you this. It’s mid-afternoon and you are walking around outdoors with your camera, and taking photos of things you find interesting. What is your ISO likely set at?
How about indoors?
From what you wrote, in poor light, 10,000 is acceptable for low light, so my D750 should be similar. I suppose I could try 6,400 ISO on the M10, the highest speed printed on the ISO wheel on top of the camera (in the menu system, I can go higher).
One other thing, that may be irrational, but I think differently than most people a lot of the time. You wrote:
I enjoy photography, and I enjoy taking photos, and I most enjoy rangefinder cameras, ever since I was a kid. Small, compact, and powerful. For “candid photos”, I greatly prefer the RF, but for carefully composed landscape type photos, I prefer a dSLR. I figure my d750 and my M10 are plenty good enough for me, and I can’t see upgrading to a d850 or for that matter, an M11.
I love what you wrote:
Another saying I love: “When you’re up to your neck in alligators, it’s hard to remember the original objective was to drain the swamp.”
…or my translation, when I’m actually trying to do something, I just do the best with what I’ve got, and don’t waste time thinking about “what if”.
You did great with the photo regardless of what camera you used. You got what you needed out of the D100, but given the choice, I’m sure you would prefer to be using a D850. For me, this means doing the best I can to capture an image, regardless of which camera and lens is hanging around my neck. Choosing what gear to use is best done in a forum, and not when you’re standing outside raising whatever camera you’ve got to your eyes. Do the best you can with whatever gear you have, and make the appropriate adjustments to the settings to optimize the results from THAT camera, right THEN.
Stenis
(Sten-Åke Sändh (Sony, Win 11, PL 6, CO 16, PM Plus 6, XnView))
39
@mikemyers The problem with the DSLR-construction is by design. There is no natural feed back/closed loop in a DSLR phase detect AF-system like it is in the mirrorless. In the DSLR:s the AF uses a separate AF-sensor and when that believes it is in focus it might not at all be in focus at the main sensor. So that is the first light path, the second is to the main sensor and the third is via the mirror through a prisma or a set of mirrors to a matte glas in the optical viewfinder. Two of these has to be adjusted/calibrated to be properly in sync with the main path to the sensor and sometimes they are not. When end control before shipping is sloppy the customers becomes the unpaid out sourced control unit instead.
Earlier DSLR:s like my KonicaMinolta D7D crap had no microadjustments like most other DSLR:s around 2005 so that camera was really a pretty hopeless “one fashion fits all” construction like the rest relative to all the lenses it had to handle, so there was really nothing to do but using Direct Manual Focus.
When microadjustment functionality came it was possible to compensate a prime but still not the zoom lenses. Sigma lenses were notoriosly bad focusing a long time and still are with some Canon and Nikon DSLR:s but the same lenses often works fine with adapters on mirrorless cameras that all use closed loop hybrid AF nowadays.
The new mirrorless AF-systems are much more accurate despite they can catch images at the double speed of the fastest DSLR:s. At least some of the faster mirrorless cameras are open continously measuring both AF and exposure. DSLR:s on the contrary are “blinded during a large part of an image cycle by the ever flapping mirror and flexing iris” which means these systems have to guess during a large part of the burst what is happening with the motif. The fastest mirrorless now measures through the active aperture the photographer and or the system has selected, up to 120 times per second and that makes a significant difference. They even cover the entire motif with focusing points and not just att the cery center of the motif as the DSLR:s.
Since I got my first mirrorless (NEX 7) and started to use lenses made for these mirrorless cameras I have never experienced any system related focusing problems. When I still had my KM D7D or some early Sony DSLR and all these focusing problems, I was really really close to give up digital photo all together. It was just loads of problems.
Why a high megapixal camera?. The more megapixels, the more pixels are involved in a motion blur. I consider you mean with high megapixel the pixel pitch.
