70-100mm VS. 100-400mm Questions?

[Jopa]

It isn't just the distance to the subject, it is the relationship between the differences between the position of the photographer and the various items within the image.

^ My 6 y.o. would probably say the same, and there is nothing wrong with it. IRL it's actually much simpler and covered in 8th grade physics (in my country) and relies on basic geometry
As you can see from the picture, the distance between two projected points depends on the viewing angle: wider the angle - more apart the projected points. Assuming you're framing the same subject, only the distance will affect your angle (and perspective distortion).

This is probably a better article https://en.wikipedia.org/wiki/Angle_of_view, but I was referring to the term "compression", and posted a different link mentioning compression.

 

[Jopa]

The authors of the wiki page make some egregious errors.

John, that's Wikipedia, and if you feel something is wrong - remember you can always contribute to the world knowledge database. And also maybe throw a few bucks into their current fundraiser

What that statement should read is, "How focal length affects perspective: it doesn't."

It doesn't indeed.

 

[Besisika]

I'm fairly new to photography.

1. I'm wondering, why not just get one long lens like a 100-400mm and use it instead of the 70-100mm if I do not need focal lengths less than 100?

2. How is the 100-400mm VS. a 70-100mm for portrait photography?

Thanks.

I don't see any difference between 135mm at 5.6 shot on 100-400mm and 70-200mm. Maybe there is but I don't see it.
Both sharp at 5.6 - 11, both have IS and both allows you for 100-200mm
When shooting in studio you mainly shoot at 5.6-11 anyway. Outdoor, background separation depends mainly on the subject to background distance so if you like the look of 5.6 there is no difference between the two lenses.
If you intend to shoot wide open, for similar background blur, then yes the two lenses are totally different. One achieve that blur mainly through F-stop (2.8), while the other through compression. That affects not only the amount of light needed but the working distance as well. But if you want a specific F-stop at a specific focal length (ex 135mm 5.6) both lenses should do the job equally very well.

For portraiture though, I prefer a prime because of weight. Bringing up and down 500 times within 2 hours a camera+ lens has an effect on your health.
So for the same working distance and F-stop I prefer a 135mm or 200mm prime (indoor with available light: 85 1.2). I bring only the 70-200 when I expect a rain, snow or dusty environment.

You would see big difference between the two when you incorporate ambient light. The 100-400 will give you only 5.6 and as a result you might need a bunch of that ambient light. This becomes obvious indoor.
Outdoor, 100-400 maybe better if you use an ND filter instead of HSS, because you start right away from 5.6. On overcast day, you may not even need any ND. During bright sunny day just a few stops while the 70-200 requires 2 stops more and your camera might have more issues focusing. When using HSS, the 100-500 needs HSS only during bright sunny day.

Finally, when shooting in crowd (not a typical portraiture but becomes more and more popular - cosplay, zombie walk, fashion show, etc) you will need an F-stop wider to knock out the background faster under the same working distance and again prime wins.
Zoom would be important only when you shoot without the ability to zoom with your feet (example fixed position when models are posing by themselves for many people to shoot at same time - fashion event, sport event, etc)

Hope that helps,

 

[AlanF]

It isn't just the distance to the subject, it is the relationship between the differences between the position of the photographer and the various items within the image.

^ My 6 y.o. would probably say the same, and there is nothing wrong with it. IRL it's actually much simpler and covered in 8th grade physics (in my country) and relies on basic geometry
As you can see from the picture, the distance between two projected points depends on the viewing angle: wider the angle - more apart the projected points. Assuming you're framing the same subject, only the distance will affect your angle (and perspective distortion).

This is probably a better article https://en.wikipedia.org/wiki/Angle_of_view, but I was referring to the term "compression", and posted a different link mentioning compression.

The diagram you have downloaded from wikipedia is inconsistent with the laws of refraction. It has rays passing through the lens unrefracted and they don't even go though the centre of the lens but intersect in front of the centre. Any 8th grade student who has the minimum of knowledge about refraction would know that the rays would be bent by the front surface of the lens and by the rear surface. A simplified diagram would at least have them going through the centre.

 

[Jopa]

It isn't just the distance to the subject, it is the relationship between the differences between the position of the photographer and the various items within the image.

^ My 6 y.o. would probably say the same, and there is nothing wrong with it. IRL it's actually much simpler and covered in 8th grade physics (in my country) and relies on basic geometry
As you can see from the picture, the distance between two projected points depends on the viewing angle: wider the angle - more apart the projected points. Assuming you're framing the same subject, only the distance will affect your angle (and perspective distortion).

This is probably a better article https://en.wikipedia.org/wiki/Angle_of_view, but I was referring to the term "compression", and posted a different link mentioning compression.

The diagram you have downloaded from wikipedia is inconsistent with the laws of refraction. It has rays passing through the lens unrefracted and they don't even go though the centre of the lens but intersect in front of the centre. Any 8th grade student who has the minimum of knowledge about refraction would know that the rays would be bent by the front surface of the lens and by the rear surface. A simplified diagram would at least have them going through the centre.

I suggest you to read the article which says "Treat the lens as if it were a pinhole at distance S2" before making "smart" comments. It's done... guess what?... for simplicity. Such type of drawing is called schematics. Next time please do not forget to take into account space warps and relativity theory

 

[AlanF]

The reason I wrote my comment was that you made a disparaging remark implying that privatebydesign is not up to 8th grade physics in your country. The simple facts are that a schematic is designed to illustrate the basic principles, and this figure doesn't. The figure shows light rays that hit outside the pinhole and don't go through it. It should have had the lines crossing through the pinhole. It is truly sloppy and something that should fail 8th grade physics.

 

[Jopa]

The reason I wrote my comment was that you made a disparaging remark implying that privatebydesign is not up to 8th grade physics in your country. The simple facts are that a schematic is designed to illustrate the basic principles, and this figure doesn't. The figure shows light rays that hit outside the pinhole and don't go through it. It should have had the lines crossing through the pinhole. It is truly sloppy and something that should fail 8th grade physics.

Don't you think that privatebydesign is NOT an 8th grader, but a grown up man that most likely doesn't need your advocacy?
8th grade physics was mentioned because it was really in 8th grade, and I'm not sure when this topic is supposed to be learned in the US. It could be sooner or later - I simply don't have this information. It was mentioned just for the reference, as simple as that, no need to try finding a negative inner meaning unless you always see the world in dark colors...

Now about schematics. Another article from the resource you love : https://en.wikipedia.org/wiki/Schematic, please read: "A schematic usually omits all details that are not relevant to the information the schematic is intended to convey". And here is an explanation for you: all the wiki authors wanted to demonstrate is a basic principle avoiding overloading it with unnecessary details. If you think you could do better - you are very welcome to draw your own chart and upload to Wikipedia so everybody can enjoy your precise drawings, and dummies like me could have access to better materials to copy-paste into CR

 

[AlanF]

As you asked.

 

[Jopa]

As you asked.

upload it to wiki!

 

[AlanF]

You do appreciate a good schematic!

 

[Jopa]

You do appreciate a good schematic!

Everybody does!

 

[Ozarker]

Even when comparing 400mm @ f/5.6 to 200mm @ f/2.8 ?

That would work. Just give your subject a walkie-talkie so you can tell him/her when to smile.

LOL that's so true. Especially when taking a full body pic of an adult. You're getting a pretty unique "compressed" look, but the lighting should be also appropriate otherwise people's faces start looking weird.

https://www.youtube.com/watch?v=ebz6Kow-ywc

Mind you I hate the term compression when people really mean perspective, but that's another thread.......

I mean what I mean https://en.wikipedia.org/wiki/Perspective_distortion_(photography)
"Perspective distortion takes two forms: extension distortion and compression distortion". Has nothing to do with the lens but the distance to the subject.

You might well mean what you mean, but using that article as any kind of authoritative confirmation is ludicrous. The author makes some good points but I disagree with the terminology which has no citations or confirming notes and the wording is ambiguous or plain wrong in places.

It isn't just the distance to the subject, it is the relationship between the differences between the position of the photographer and the various items within the image.

Besides, I wasn't referring to you about using compression because you had the good sense to cover it's use with quotation marks, I meant the guy in the video and various other educators who clearly never had any kind of formal education in photography and just repeat, parrot fashion, expressions they hear.

Ahhhh... Yeah, the guy in the video should have used "finger quotes" and then we wouldn't be nit-picking.

 

[Jopa]

Even when comparing 400mm @ f/5.6 to 200mm @ f/2.8 ?

That would work. Just give your subject a walkie-talkie so you can tell him/her when to smile.

LOL that's so true. Especially when taking a full body pic of an adult. You're getting a pretty unique "compressed" look, but the lighting should be also appropriate otherwise people's faces start looking weird.

https://www.youtube.com/watch?v=ebz6Kow-ywc

Mind you I hate the term compression when people really mean perspective, but that's another thread.......

I mean what I mean https://en.wikipedia.org/wiki/Perspective_distortion_(photography)
"Perspective distortion takes two forms: extension distortion and compression distortion". Has nothing to do with the lens but the distance to the subject.

You might well mean what you mean, but using that article as any kind of authoritative confirmation is ludicrous. The author makes some good points but I disagree with the terminology which has no citations or confirming notes and the wording is ambiguous or plain wrong in places.

It isn't just the distance to the subject, it is the relationship between the differences between the position of the photographer and the various items within the image.

Besides, I wasn't referring to you about using compression because you had the good sense to cover it's use with quotation marks, I meant the guy in the video and various other educators who clearly never had any kind of formal education in photography and just repeat, parrot fashion, expressions they hear.

Ahhhh... Yeah, the guy in the video should have used "finger quotes" and then we wouldn't be nit-picking.

LOL. But nitpicking generates 95% comments on this forum BTW.

 

[Ozarker]

Even when comparing 400mm @ f/5.6 to 200mm @ f/2.8 ?

That would work. Just give your subject a walkie-talkie so you can tell him/her when to smile.

LOL that's so true. Especially when taking a full body pic of an adult. You're getting a pretty unique "compressed" look, but the lighting should be also appropriate otherwise people's faces start looking weird.

https://www.youtube.com/watch?v=ebz6Kow-ywc

Mind you I hate the term compression when people really mean perspective, but that's another thread.......

I mean what I mean https://en.wikipedia.org/wiki/Perspective_distortion_(photography)
"Perspective distortion takes two forms: extension distortion and compression distortion". Has nothing to do with the lens but the distance to the subject.

You might well mean what you mean, but using that article as any kind of authoritative confirmation is ludicrous. The author makes some good points but I disagree with the terminology which has no citations or confirming notes and the wording is ambiguous or plain wrong in places.

It isn't just the distance to the subject, it is the relationship between the differences between the position of the photographer and the various items within the image.

Besides, I wasn't referring to you about using compression because you had the good sense to cover it's use with quotation marks, I meant the guy in the video and various other educators who clearly never had any kind of formal education in photography and just repeat, parrot fashion, expressions they hear.

Ahhhh... Yeah, the guy in the video should have used "finger quotes" and then we wouldn't be nit-picking.

LOL. But nitpicking generates 95% comments on this forum BTW.

Yup.

 

[Loswr]

LOL. But nitpicking generates 95% comments on this forum BTW.

Technically, I think it's closer to 96.5%. Also, you should have placed a comma after the word 'forum' in your post.

;D

 

[Jopa]

LOL. But nitpicking generates 95% comments on this forum BTW.

Technically, I think it's closer to 96.5%.__Also, you should have placed a comma after the word 'forum' in your post.

;D

It looks like our next nitpicking war is going to be around this topic: https://en.wikipedia.org/wiki/Sentence_spacing

 

[Loswr]

LOL. But nitpicking generates 95% comments on this forum BTW.

Technically, I think it's closer to 96.5%.__Also, you should have placed a comma after the word 'forum' in your post.

;D

It looks like our next nitpicking war is going to be around this topic: https://en.wikipedia.org/wiki/Sentence_spacing.

Before discussing acceptable options regarding moving from one sentence to the next, I believe we should discuss the proper way to end the first sentence: https://en.wikipedia.org/wiki/Full_stop.

 

[stevelee]

From the Wikipedia article on Murphy's Law:

Hartman's law of prescriptivist retaliation: "Any article or statement about correct grammar, punctuation, or spelling is bound to contain at least one eror." Named after journalist Jed Hartman.

 

[AlanF]

From the Wikipedia article on Murphy's Law:

Hartman's law of prescriptivist retaliation: "Any article or statement about correct grammar, punctuation, or spelling is bound to contain at least one eror." Named after journalist Jed Hartman.

It's an example of Muphry's Law (https://en.wikipedia.org/wiki/Muphry's_law).