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11-08-2017, 08:27 AM   #106
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QuoteOriginally posted by audiobomber Quote
I read DPR news daily. They report on new lenses and across all systems, 1", m4/3, FF, MF. In order to understand a lens' operating parameters, I need to convert.
I don't. It's just a "hmm... so that's as if I cropped my K-1's image to half the size", more or less. And I know more this way.

11-08-2017, 08:36 AM   #107
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QuoteOriginally posted by Rondec Quote
I mentioned above, but a lot of people have the perception that a 200mm f2.8 lens on micro 4/3 is the same as a 400mm f2.8 lens on a K-1. It is nice to be able to explain why they aren't exactly the same lens. Because based on apertures and angle of view, micro four thirds kills cameras with bigger sensors. Except it doesn't really.
My response to that is this image....


You'd need a 1200mm lens on an FF or 800mm lens on APS-c, and I got this with a camera i can almost slip in my pocket.

In some ways, small sensors do "kill" larger sensors. You just have to understand the limitations, it doesn't kill on every image but it will on a few, and at times it won't even be useful, but when it does what it does, ya, it kills larger formats. Every format has it's strengths and weaknesses. Smaller formats tend to be less strengths and more weakness, but they still do well what they do well.

On a really bright day, (100 or 200 ISO) with a relatively stationary subject so you can use the 2 second delay on a tripod and a subject that needs some serious depth of field to keep it all in focus ) I'll take my XG-1. And there are other serious advantages, like being able to use the camera like a spotting scope, because it ranges from 4.5mm to 233mm. You zoom out and find your subject then slowly zoom in keeping the bird in frame. No searching the trees through a very narrow FoV trying to find your subject.

It isn't the same really, but sometimes it's better, in many ways, and while the IQ may not be the same, as long as it's good enough for the purpose intended, no one cares how much extra resolution you are throwing away when you downsize the image. That one is 16 MP reduced to 4, do I care if it was 36 MP reduced to 4? it would still be 4 MP.

When discussing equivalence you are actually discussing very little about these camera systems, and probably the least important. It's all about a theory with very little to offer apart from academic comparisons.

Last edited by normhead; 11-08-2017 at 09:03 AM.
11-08-2017, 08:47 AM - 1 Like   #108
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QuoteOriginally posted by normhead Quote
My response to that is this image....


You'd need a 1200mm lens on an FF or 800mm lens on APS-c, and I got this with a camera i can almost slip in my pocket.

In some ways, small sensors do "kill" larger sensors. You just have to understand the limitations, it doesn't kill on every image but it will on a few, and at times it won't even be useful, but when it does what it does, ya, it kills larger formats. Every format has it's strengths and weaknesses. Smaller formats tend to be less strengths and more weakness, but they still do well what they do well.

On a really bright day, (100 or 200 ISO) with a relatively stationary subject so you can use the 2 second delay on a tripod and a subject that needs some serious depth of field to keep it all in focus ) I'll take my XG-1. And there are other serious advantages, like being able to use the camera like a spotting scope, because it ranges from 4.5mm to 233mm. You zoom out and find your subject then slowly zoom in keeping the bird in frame. No searching the trees through a very narrow FoV trying to find your subject.
But Norm, that's the perfect example of what Dan (Audiobomber) is saying. It isn't a very good image. The K3 images you have posted have significantly better detail and are better shots all around than that shot is. That shot looks almost like an impressionistic painting -- you can definitely identify the bird, but I wouldn't imagine you could print it over 5 by 7 without it looking all pixelated.

There is no magic bullet that takes the place of getting close to wildlife. Shooting a 200mm lens on a Q is appealing, but it is really tough from what I've seen to get results that actually match, say, a 300mm lens on a K3.
11-08-2017, 09:10 AM   #109
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Thats where you and I differ. I think shots like this can have too much detail. Take this one for example....


Sharper but messy. As for looking pixellated, it's a 16 MP image, it's not going to look pixellated. The first isn't as sharp, but really which one do you want to look at? If you prefer the top image, then the first image is better. It's not about the technical attributes of the Image. Come on, you gotta admit that bottom image is so sharp it hurts your eyes.

Looking at the original from the earlier post, the reason it's soft is I'm pretty sure it was taken with the "landscape" filter turned on. Maybe on the next bright day I'll get a better one.

To be continued.


Last edited by normhead; 11-08-2017 at 09:34 AM.
11-10-2017, 03:26 AM   #110
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I think this guy explains better than Tony Northrup the DOF, bokeh & Perspective between crop and full frame. He doesn't talk about the exposure between crop and full frame when he stots at the same aperture on both cameras, but (if anyone had doubts) from his examples it is pretty obvious that the exposure doesn't change.

full-frame vs crop-sensor comparison

Last edited by Dan Rentea; 11-10-2017 at 03:32 AM.
11-10-2017, 04:08 AM   #111
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QuoteOriginally posted by normhead Quote
Thats where you and I differ. I think shots like this can have too much detail. Take this one for example....


Sharper but messy. As for looking pixellated, it's a 16 MP image, it's not going to look pixellated. The first isn't as sharp, but really which one do you want to look at? If you prefer the top image, then the first image is better. It's not about the technical attributes of the Image. Come on, you gotta admit that bottom image is so sharp it hurts your eyes.

Looking at the original from the earlier post, the reason it's soft is I'm pretty sure it was taken with the "landscape" filter turned on. Maybe on the next bright day I'll get a better one.

To be continued.
You can take nice images with any camera. Images really aren't about the camera you are using, number of pixels -- they are about light and composition and subject. That said, I will freely admit that if everything else is equal, I have an awful lot easier time taking good images with a K-1 or a K3 than with my cell phone camera. There are a number of reasons for that -- I feel like limitations in dynamic range, I see diffraction with it, and the jpegs out of camera with my iphone 7 feel over sharpened and over saturated with colors that are just "off."

As for stopping down with a K-1, I do it plenty and when I am shooting landscape photos, I typically will shoot at f11. That's plenty of depth of field when combined with a wide angle lens. I seldom shoot telephoto shots and don't own a full frame lens longer than the DFA 70-200, so I'm a little lost on that.

Regardless, people should shoot with what they have. Every size sensor camera has come a long ways over the years -- from cell phones to medium format -- and if you can't get some decent images with them, the problem probably isn't the camera.
11-10-2017, 08:31 AM   #112
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QuoteOriginally posted by Dan Rentea Quote
I think this guy explains better than Tony Northrup the DOF, bokeh & Perspective between crop and full frame. He doesn't talk about the exposure between crop and full frame when he stots at the same aperture on both cameras, but (if anyone had doubts) from his examples it is pretty obvious that the exposure doesn't change.

full-frame vs crop-sensor comparison
It's good as far as it goes, but discussing equivalent focal lengths without discussing equivalent apertures is missing a critical point. He should have showed equivalent images, e.g
  • APS-C, 55mm @ f1.8, 1/4000s, ISO 100
  • FF, 85mm, f2.8, 1/4000s, ISO 250
  • APS-C 55mm, f8, 1/100s, ISO 800
  • FF, 85mm, f13, 1/100s, ISO 2000

These images would show similar FOV, DOF, DR, perspective, diffraction and noise.

QuoteOriginally posted by normhead Quote
You mean before or after he changed his pages to take into account some of my criticisms? Honestly, people have told me he's made changes, but I'm not checking his pages for accuracy unless paid. It's work. But take "Don't use full fare lenses on APS-c" if you must, It's a ridiculous argument. Go through the video and follow his logic. You tell me how he ends up with such a conclusion.
The title is meant to grab attention. He makes two main points about lenses::
1. If you shoot APS-C, an APS-C standard zoom (18-55) would be a better choice than a FF standard zoom.(28-70), because with a FF lens you don't get wide angle with the FF lens.
2. Don't expect a FF standard zoom to give the same resolution on APS-C as it does on FF.

Neither point should be controversial.


Last edited by audiobomber; 11-10-2017 at 11:19 AM.
11-10-2017, 09:15 AM   #113
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I'm sorry, Dan, but it seems to me you're trying to make sense of his video by skipping over the many things that don't. Especially over how he's making a point in (ab)using "equivalence".

If you want to figure out if a 28-70mm is or not wide enough on a certain format, you must not use any form of "equivalence". Any needless reference to another format is a confusion generating mistake, and that is a fact.
Lenses should be compared based on their own characteristics, without preconceived ideas. Actually I do not believe that the 24-70 f/2.8 II - to use the current version, and not the ancient one launched in 1993 - is any worse than any EF-S 18-55mm, closed down 1-2 stops (i.e. at about the same apertures).

The second part I've already talked about in a previous post - i.e. if you crop the borders out of the image, you'll lose all the border detail. I'm sure you don't need "equivalence" to figure that out either.

Last edited by Kunzite; 11-10-2017 at 09:25 AM.
11-10-2017, 09:46 AM   #114
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Obviously if you are using a Takumar 55 1.8 on a crop sensor you should actually be using the proper lens like a DA 55 1.8 to achieve the correct dof. It is wrong to use a FA43 or 77 when the correct lenses are the 40 and 70?

I shoot three formats in large format and the only concern LF shooters have in using a lens in a different format is there sufficient coverage.

I use DA lenses on my MZ7 and full frame ones on my K5iis choosing by the complex calculation of which lens that I own will be best for this particular shot (assuming I have it with me). Same with medium format or large format.
11-10-2017, 09:54 AM   #115
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"Correct"? What on Earth is that?
11-10-2017, 09:55 AM   #116
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QuoteOriginally posted by audiobomber Quote
The title is meant to grab attention. He makes two main points about lenses::
1. If you shoot APS-C, an APS-C standard zoom (18-55) would be a better choice than a FF standard zoom.(28-70), because with a FF lens you don't get wide angle with the FF lens.
2. Don't expect a FF standard zoom to give the same resolution on APS-C as it does on FF.

Neither point should be controversial.
Would anybody except a complete newbie not understand this and they aren't going to make much sense of the convoluted reasoning over DOF or resolution either.
11-10-2017, 10:10 AM   #117
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QuoteOriginally posted by mohb Quote
Would anybody except a complete newbie not understand this and they aren't going to make much sense of the convoluted reasoning over DOF or resolution either.
That was going to be my question. What kind of person can look through the Viewfinder of a K-1 and a K-3 and not understand the difference? And should such persons be owning DSLR's anyway?

I went from FF film to my *ist without giving it a thought. I bought the kit lens, 18-55 which worked like a kit lens, I bought the Sigma 70-300 which was at that time the best telephoto I'd ever owned. When I found out I was using a crop sensor I was shocked. When I found out some folks were looking down their nose at me because I was shooting a crop sensor I was even more shocked. It was incomprehensible to me, that people would think that amateurs thought they were better than me, despite their lack of training, because they had a bigger format. Nothing in my photographic training prepared me for that. I was taught use the format that is the best for what you are doing, at the moment you are doing it. No one ever tried to make a case for one being better than the other.

I suspect the "what kit lens should I buy" issue might be more of an issue for non-pentax shooters where the lens line-ups don't include as much quality APS-c glass.

But honestly, who goes out and buys a lens without regards to the focal length? Isn't understanding focal length the first thing you have to know before you go out and buy a lens.

When I got my Sigma 70-300 I was in the store had already ordered the *ist D and 18-55, and the guy put a Sigma 70-300 on my camera and said "Look at this, you'll love it." I did and I did. Did I understand "equivalence" as a theory, hell no, I didn't even know I had a crop camera. But I liked what I saw. That's all I needed. Apparently some people need more.

The funny thing about that was I had to research equivalence to be able to show people their approach was in error. Anyone who uses multiple formats understands "equivalence" intuitively. It's just guys like Northrup who muddy the waters.

Last edited by normhead; 11-10-2017 at 10:15 AM.
11-10-2017, 10:27 AM   #118
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I'll just add my 2 cents on the equivalence discussion.

I jumped onto the photography train (to bankrupcy) in the summer of 2015 when I could finally afford my own DSLR. I luckily chose the Pentax K-3 as my camera since it was on offer and had great features. I bought the DA 18-55, DA35, DA50 and Sigma 70-300 lenses with it. The 35mm for me was a wide-ish lens while the 50mm was a tight lens. The 18mm end of my zoom was my wide angle while the 300mm was my telephoto.

And that's all I needed to know to be happy with my shooting.

Two years on, I've got a K-1 and more lenses than I can count. I still take crop factors into account for my lenses on the K-1 or KP (e.g. My A20/2.8 gives me the same FoV on the K-1 as a 13mm lens would on APS-C). It's an automatic thing. I really don't care much for DoF equivalence because I'm going to try and use the best lens I can possibly use for each system. But when it comes to FoV equivalence, it's taken me a while to get used to facts such as 28mm being a pretty wide angle on FF.
11-10-2017, 10:46 AM   #119
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QuoteOriginally posted by HarisF1 Quote
Two years on, I've got a K-1 and more lenses than I can count. I still take crop factors into account for my lenses on the K-1 or KP (e.g. My A20/2.8 gives me the same FoV on the K-1 as a 13mm lens would on APS-C). It's an automatic thing. I really don't care much for DoF equivalence because I'm going to try and use the best lens I can possibly use for each system. But when it comes to FoV equivalence, it's taken me a while to get used to facts such as 28mm being a pretty wide angle on FF.
I've spent enough time with my K-1 and K-3, I see an image and, I think, "I want this lens on this body." It's the memory of what each lens does in particular set of circumstances that is important. I use the K-1 unless a particular set of circumstances says I'd be happier with another camera. But there are lots of those circumstances. Those decisions are made not by "equivalence", but by how that lens renders on that format. This is what is so frustrating about this type of discussion. The important thing is what lens can you use to get the look you want. That's what is important. Equivalence is an irrelevant detail. You don't have to know what the theory behind equivalence is to be great photographer. Or to understand what lens you want to use. The fact that I like the FA 50 macro on FF does not mean I would like the 35 macro on APS-c. Practically, equivalence is of no value and is a distraction. What is of value is know the lenses you own and how they render in the various circumstances you find yourself shooting.

I bought the DA 35 2.4 because it was supposed to be equivalent to a 50 on FF. It's not. I don't like it's images on either FF or APS-c. Equivalence is nonsense. There could be a 35 out there that I would like, but it's about that lens, not it's equivalent focal length. I'll never own that lens though because I really like the 40XS. That's close enough for me.

Last edited by normhead; 11-10-2017 at 10:55 AM.
11-10-2017, 11:04 AM   #120
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On that note, the KP with the DA15, DA40XS and the FA77 is an unbeatable kit. I actually prefer it in lieu of the K-1 if I'm going to be walking for a while. Otherwise I know that the K-1 is amazing with the A20 and FA85. My FA31 sees very little use in comparison to my other stuff.
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