What do you want to understand better about photography? (1 Viewer)

[JohnRice]

A couple blasts from a former time, complete with dust. I'm thinking a darkroom and 4x5 film holders aren't something I'll be needing in the future. I'd sure like to find a buyer for that enlarger. Might be difficult. It's not easily shippable. LOTS of other darkroom gadgets around here as well.

 

[Scott Merryfield]

Cool stuff, John. Developing my own film was something I never did, but kinda regret for missing the experience. But, no, that doesn't mean I want to buy your enlarger.

 

[JohnRice]

I came across this video... and stuff like this just annoys me. So, to clarify the issue, the size of the sensor (whether it's electronic or organic) does influence depth of field, when everything else is equivalent. By equivalent, I mean two images that are identical, aside from the inherent differences in the sensors/film themselves.

So, here's the video...



Yes, larger sensors DO produce shallower depth of field, when everything is equivalent. In that video, they're doing all sorts of things to produce two dissimilar images, in an effort to prove the common belief is wrong, when it isn't. They kind of, in a roundabout way, admit it is true, but they're presenting images that aren't the same.

If you are creating a certain composition, that means photographing a subject from a specific location. The only way to produce that specific image, is from that specific location. If you move to a different location, it's a different image. So, to make the comparison easy, let's compare full frame and Micro 4/3s, since the lens factor is 2:1. If you shoot a certain photo with full frame, then you would shoot the same image with a lens with 1/2 the focal length, from the exact location, to produce an identical image. I'll reiterate, if you use the same focal length lens and move twice as far away with the Micro 4/3 camera, that will produce a significantly different image.

If you shoot those two images from the same location, one right after the other, using a focal length lens on the Micro 4/3 that's 1/2 the full frame, at the same aperture, the shot using the full frame camera will have less depth of field, but otherwise they will be identical. How people posting videos online "educating" others on photography can not understand that is beyond me. Imagine if you had spent your life using equipment ranging from 35mm to 4x5" sheet film, even some 8x10", intrinsically understanding how the size of the "sensor" influences depth of field.

 

[JohnRice]

In fact, the video he referred to at the beginning demonstrates two things. First, it shows how the size of the sensor does change depth of field, when everything else is equivalent. He took two shots from a long distance, with the same camera at the same aperture. One with a long lens, and one with a short lens. He then cropped the one with the short lens to produce the same composition as the one with the long lens. Well, in a roundabout way, he just changed the shot with the short lens to be as if he shot it with a camera with a very small sensor. So, the shot with the 400mm lens is equivalent to the shot with a 24mm lens, if it had been shot using a camera with a tiny sensor. That's why the composition of the shots are identical, but they have widely different depth of field. So, he started off the video disproving what the title says.

He also says his previous video "debunked" lens compression, which is also a serious misinterpretation. Photos aren't technically compressed due to the lens. They are compressed (again) due to your distance from the subject. Then you typically use a long lens to bring that distant subject up close. So, the lens isn't really compressing the image, your distance from the subject is. It just helps you see the compression. Think of it this way, say you're photographing a flower that measures 3" from front to back. If you photograph it from 3" away with a short lens, then the furthest point on the flower is twice as far away as the closest. Now, say you switch to a long lens and shoot it from 3' away. Now the closest point on the flower is 3' away, and the furthest is only 3' 3" away. Only slightly further than the closest, rather than twice as far, so it will look far more compressed. The lens technically didn't do that. You did by choosing your shooting location, but the lens brought it all together, and your choice of lens played a huge part in where you shot the photo from. This is why I like having several macro lenses ranging from 15mm to 150mm.

It's an absolute disgrace that people like Fstoppers don't know these things inside and out already. They shouldn't be doing these experiments to "discover" it. They should already know it, and be creating the video to demonstrate it. What's the difference? Their conclusions are wrong and what they're teaching is wrong, because they still don't understand WHY it works the way it does. They're just observing things and believing that makes them understand why things happen the way they do. The result is that people come away more confused, but believing they know more, when they really don't.

 

[Scott Merryfield]

John,

There's lots of confusion regarding crop sensors versus so-called "full frame" sensors, so it's a shame when a website attempting to educate gets it wrong. There are already too many people out there who think a 400mm lens magically becomes a 640mm lens when put on a crop body. Honestly, for the majority of folks who only shoot with one sensor size, they shouldn't even worry about the "crop factor" of their sensor. Heck, even though I shoot with both a full frame and APS-C sized sensor, I don't really concern myself too much with that crop factor -- I just inherently know which focal lengths I need for certain situations after shooting both formats for so long. That crop factor does come in handy in putting "more pixels on target" when I shoot wildlife with my telephoto on my crop Canon 7D2, but that's about the most I think about it.

 

[Scott Merryfield]

When we were walking around the zoo on Sunday morning, I saw a person with a dSLR with the lens hood mounted in its reversed "storage" position while shooting. I am amazed at how many times I actually see this, and wonder if the hood was shipped that way and the person has always left it there, completely unaware of how a hood works and its benefits.

Personally, the only times I am not using the hood is if I am using my Lee filter system or if the hood casts a shadow while using an external flash (the latter rarely happens). I don't have hoods for my two pancake lenses, but have them for every other lens. I've been ordering 3rd party hoods for the lenses that do not come with one, as they are less than half the price of Canon's hoods. Since it's just a piece of plastic, as long as the hood fits well it really doesn't matter if it has a Canon label.

 

[JohnRice]

Yeah, I'm with you Scott. The really bizarre thing is most zooms are almost impossible to use with the hood reversed.

 

[JohnRice]

Well, this is interesting. I've been looking around to see what stuff I have collected might be worth selling. The lens on the enlarger I posted earlier turns out to be worth something. As in, it could mostly or even completely fund a new PowerSound Audio S3010 subwoofer. It was going for some lofty prices, and it's no longer made. The problem is, it's difficult to set a price, because I looked everywhere and I can't find a single one for sale, anywhere. eBay, B&H, KEH, Adorama, nobody has a single one for sale.

 

[JohnRice]

OK, here's another big peeve for me. Over 20 years into digital photography, and so many people, I mean people who do this for a living, still talk about dpi like it means anything. The "art director" at this magazine I'm submitting some stuff to continuously says the images need to be 300 dpi. I'm tempted to send 1"x1" images, at 300 dpi, and see what happens.

Just an FYI, dpi (or ppi, if you want to pick nits) simply designates how pixels are distributed. It has nothing to do with how many pixels there are or how large an image can be reproduced. A 20MP image is a 20MP image, regardless of how those pixels are distributed. Yeah, there's a completely meaningless, technical difference, but it IS meaningless for someone who knows what they're doing.

 

[JohnRice]

I just learned something. I'm hoping a lot of you shoot and work with 16 bit, AdobeRGB images, then convert them down to what you need for the final image. It appears I've been doing this conversion wrong. I haven't researched this further yet, but it's difficult to get accurate answers, such as Ken Rockwell's (typically narrow minded) input on the subject, which is the first search result I get. I would always flatten my Photoshop image, resize it, convert it to 8 bit, then convert it to sRGB. From what I now understand, I was doing those last two steps in the opposite order from what I should. This is something I'd sort of wondered about. To explain briefly, it has to do with how fine the color gradations are in each color space and bit depth. AdobeRGB has wider gamut, so at a given bit depth, it has larger color gradations than sRGB, to accommodate the wider gamut. I genuinely don't know if that's correct, but the explanation makes sense. A 16 bit AdobeRGB image still has significantly finer color gradation than an 8 bit sRGB image. So, if I convert to 8 bit before sRGB, I've already thrown out the finer gradations I get with 8 bit sRGB. If I convert to 16 bit sRGB, then to 8 bit, I should produce a slightly better image.

Anyone have any input?

 

[Scott Merryfield]

I don't use AdobeRGB, John, so cannot offer much insight here. All my cameras are set to use sRGB color space. I find it simpler than having to worry about when and how to convert from AdobeRGB.

 

[JohnRice]

It's sort of a shame that AdobeRGB is so widely ignored, but compatible monitors are rare, expensive, and very few people, no matter how many pics they take, are willing to use and calibrate them. sRGB was established for monitor use, and AdobeRGB for CMYK reproductions. What's a shame is that basically any pigment or ink based print can reproduce AdobeRGB, but since so few people use it, virtually all printing services have calibrated their equipment to simply throw away that extra color range and input only sRGB gamut.

I started right off using AdobeRGB, because the printing place next door to work used it, but they closed down. I've continued shooting with it, because I've already gotten used to it. It's always there if I want or need it, and it's simpler to leave the cameras set to AdobeRGB all the time. The amazing thing is, that with the explosive growth of people shooting HD video, more and more monitors are now capable of reproducing AdobeRGB, but those same people continue to be ignorant of it. Apple upgraded all the iMacs to be capable a few years ago. What discourages me is I'm finding that even a lot of magazines, which are the biggest reason AdobeRGB was established, have no idea what it is. I mean, when you ask an art director if they want sRGB or AdobeRGB, they have no idea what you're talking about. Sometimes it seems like the more advanced our technology gets, the more ignorant we get about it.

 

[Mike Frezon]

"What do I want to understand better about photography?"

How not to be an idiot.

Peg and I were traveling home from a few days in VT. I wanted to stop at a favorite spot on Lake Champlain and take a few photos of my dogs.

So I took several. I decided to break out my underused 50mm lens. Fortunately when I was done I decided to look at some of the images in the display screen on the camera. Normally, I wouldn't even have thought to do so. Most nearly all were blurry!

So I was upset because I had screwed up some great poses by the dogs.

I figured it must've had something to do with that lens (which I hadn't used in a long while).

So, I broke out my more often-used 18-55mm lens and took a couple practice shots and all was fine. I set the dogs up again and took more images. We were running late by this time. I looked at a few images on the display and they looked better.

But when I got home and off-loaded all the pix onto my computer, the second round wasn't really all that much better. While the the 2nd set of pix weren't as blurry, they were still soft.

I took a closer look at the camera and realized that my wheel setting was moved off "P" to "Tv." (Program to "Time Value" mode.) And the shutter speed was set to 1/15.

This is a setting I rarely change. I figure it happened the day before when I took the two dogs on a long hike. At some point I must have accidentally knocked the wheel.

And what's sad is the shots are mostly all gone. And while I did some things right in checking my work and troubleshooting...I didn't figure it out...when I should have.

Time for me to learn some basics to avoid making that kind of newbie error again.

 

[Sam Posten]

The nice thing about using a camera with a mirror is you should be able to physically hear when your shutter is lagging, at least when slower that 1/50th or so. A 1/15th of a second is in the slow lane. Keep alert for it!

 

[JohnRice]

@Mike Frezon we've all done things like that. Such as, I've had plenty of times when I was printing color negatives, but thinking like I was printing transparencies. So I would increase the exposure, to find the print got darker, increase it more, darker, when I wanted lighter. I was doing a commercial shoot of airplanes once with my Bronica, and discovered I'd taken several shots with the multi-exposure lever flipped on. So, I'd taken 10 or so shots on a single frame of film and had to tell them we needed to do them over again.

 

[Mike Frezon]

I had an Olympus OM-10 back when I was shooting film and on more than one occasion didn't realize the film hadn't "caught" and been advancing until I went to rewind it into the spool only to have that process take only a second.

I've been thinking a lot of those days since this screw-up yesterday.

I appreciate the kind words, John...but I had all the evidence in front of me when I saw the blurry pictures and added up 2+2 and got 5. That's what's so frustrating for me. The stupid test picture I took of my car (in between the two sets of dog pix) came out fine (after I had swapped out the lenses) only because the sun had broken out from behind some clouds...but only temporarily.

I need to know more about what I'm doing so that I'm not just relying on the camera to take care of everything for me.

I think after I retire (which I think isn't all that far off for me) I'm going to take some basic photography classes (with an emphasis on the technical process)...if I can find such a thing.

 

[Scott Merryfield]

Mike, take heart. As John said, we've all done stupid things at times. My mode wheel will get moved sometimes, too. My default use mode is aperture priority (Av on Canon bodies), but occasionally the wheel gets jostled to M and I don't always notice -- and it's pure luck if the exposure is correct. Sometimes I also forget to dial my ISO setting back down after raising it for a low light shot. Also, when I owned the original version of Canon's 100-400L lens, I would sometimes forget to re-engage the image stabilization after using it on a tripod (the IS was an older version which didn't work on a tripod). I then would get frustrated as the image moved around in the viewfinder as I was composing, until it would finally click that I needed to IS back on.

One thing that does help regarding exposure and your mode dial possibly getting moved, is to setup your image review on the LCD so it also displays the histogram (and learn how to read it). I usually have the histogram on, which allows me to quickly notice if something is amiss. Occasionally, though, if I am reviewing images or showing the day's shoot to my wife while we are traveling, I turn the histogram off and then forget to turn it back on. That's usually when a moved mode dial screws things up for me.

As for learning photography, your local community center or community college may offer something. I would also recommend the book Understanding Exposure as a nice self-guided learning tool of the basics.

 

[Sam Posten]

I was just about to recommend that @Scott Merryfield =)

 

[JohnRice]

Autumn is coming, so I have a suggestion on how to approach fall colors in a different way. Leaves are absolutely fascinating when light is shining through them. Even when it isn't autumn, look at the difference in their saturation with the sun shining through them rather than on them. Then look at them very close, and what you'll find is kind of incredible.

So, grab your macro lens(es). You all have at least one, right? You should. I know that since I got back into photography I've kind of gone overboard. I've always been someone who discourages going equipment crazy, but I guess I decided I want whatever tool available for any photo I visualize. Anyway, I'm not going to admit to how many macros I have. Look close at leaves, and just foliage in general, and let the sun shine through it.

Believe it or not, the color in these shots hasn't been enhanced very much, if at all.

 

[JohnRice]

In case anyone wants to know how to unintentionally piss off and confuse a lot of photo geeks, go into an online forum, such as one dedicated to Nikon, and comment that maybe people would benefit by putting more energy into developing photographic skills and less energy into how expensive their equipment is. I phrased it more tactfully than that.

It got to the point where I finally said, "Better equipment is better, but it won't make you a better photographer. The only thing that will make you a better photographer is working to be a better photographer." I coldn't even say that without getting a bunch of argument. Is it really that impossible to distinguish between skill and hardware? I'm really threatening a lot of people's self worth in that one.