john*thomas
Senior Member
Re: July 2014 Monthly Assignment - Nifty Fifty(ish)!!
Any leeway at all with a zoom?
Any leeway at all with a zoom?
Nifty Fifty Assignment Lens Discussion
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Re: July 2014 Monthly Assignment - Nifty Fifty(ish)!!
For this challenge only: All images must be taken with a 50mm FX or equivalent lens (CX: 18.5mm - DX: 35mm) OR an equal focal length with a zoom.
For this challenge only: All images must be taken with a 50mm FX or equivalent lens (CX: 18.5mm - DX: 35mm) OR an equal focal length with a zoom.
Slipperman
Senior Member
Re: July 2014 Monthly Assignment - Nifty Fifty(ish)!!
ok, now i'm really confused. i have a D5100 and recently bought a 50mm 1.8g prime so i thought i was golden but now i'm not so sure with all this 50 = 35 but only if it's FX stuff. does my prime meet the requirements or not? that's all i need to know..
ok, now i'm really confused. i have a D5100 and recently bought a 50mm 1.8g prime so i thought i was golden but now i'm not so sure with all this 50 = 35 but only if it's FX stuff. does my prime meet the requirements or not? that's all i need to know..
RocketCowboy
Senior Member
Re: July 2014 Monthly Assignment - Nifty Fifty(ish)!!
Unfortunately, no. The D5100 is a DX sensor, so 35mm is what you're looking for this month.
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Unfortunately, no. The D5100 is a DX sensor, so 35mm is what you're looking for this month.
Sent from my iPad using Tapatalk
Michael J.
Senior Member
Re: July 2014 Monthly Assignment - Nifty Fifty(ish)!!
No, cos 50x1.5=75mm on DX and a 35 x1.5=52.5mm on DX
As I understand this thread it is all about focus length of 50mm. So if you have a zoom on your DX zoom from 33mm to 35mm and you are on the safe side for this competition.
No, cos 50x1.5=75mm on DX and a 35 x1.5=52.5mm on DX
As I understand this thread it is all about focus length of 50mm. So if you have a zoom on your DX zoom from 33mm to 35mm and you are on the safe side for this competition.
Re: July 2014 Monthly Assignment - Nifty Fifty(ish)!!
On a D5100, your 50mm does not meet the requirements.
On your D5100, the effective focal length is 75mm. Doing the math, the focal length required for a 50mm equivalent on DX is ~ 35mm (35 x 1.5) and ~ 18.5mm on CX (18.5 x 2.7 multiplier).
On a D5100, your 50mm does not meet the requirements.
DX sensors capture a smaller field of view, so it makes it appear as if you’re shooting with a longer focal length lens. This is called the ‘crop factor’, and you need to multiply a lens’ actual focal length by 1.5 to get its effective focal length on a DX camera.
On your D5100, the effective focal length is 75mm. Doing the math, the focal length required for a 50mm equivalent on DX is ~ 35mm (35 x 1.5) and ~ 18.5mm on CX (18.5 x 2.7 multiplier).
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Slipperman
Senior Member
Re: July 2014 Monthly Assignment - Nifty Fifty(ish)!!
ok.. i think i got it. thx for the responses. shame though.. would have given me an excuse to use my new lens which i haven't done much of since i bought it. but i do have the 18-140mm that i can set to 35mm. definitely don't want to go back to my kit lens.
but did i make a mistake getting the 50mm instead of the 35mm 1.4? what's really the difference besides the focal length?
ok.. i think i got it. thx for the responses. shame though.. would have given me an excuse to use my new lens which i haven't done much of since i bought it. but i do have the 18-140mm that i can set to 35mm. definitely don't want to go back to my kit lens.
but did i make a mistake getting the 50mm instead of the 35mm 1.4? what's really the difference besides the focal length?
Bob Blaylock
Senior Member
Re: July 2014 Monthly Assignment - Nifty Fifty(ish)!!
I think we need to stop and clarify what the actual parameters are of this challenge.
I interpret the initial description to mean that we should use a “normal lens”.
50mm is nominally considered a “normal lens” for a 35mm camera, hence the name of this challenge. I think it is clear, however, that for anything other than a 35mm camera, of a full-frame FX format digital, that we should use a lens that is of a focal length that is “normal” for the format that we are using.
According to the Wikipedia article on the subject of Normal lens it is most purely defined as being a lens whose focal length is approximately equal to the diagonal measurement of the frame, and approximates the field of view of a human eye. Although 50mm is considered “normal” for a 35mm film frame, the actual frame has a diagonal of √(36² + 24²) = 43.266…mm so that would be the true, purest “normal” lens for this format.
According to the specifications for my D3200, the sensor is 23.2mm ×15.4mm. So, √(23.2² + 15.4²) gives me 27.846…mm.
The Wikipedia states that “For a 35 mm camera with a diagonal of 43 mm, the most commonly used normal lens is 50 mm, but focal lengths between about 40 and 58 mm are also considered normal. The 50 mm focal length was chosen by Oskar Barnack, the creator of the Leica camera.”. For the sensor in my D3200, the equivalent range would be approximately 27.74mm to 37.328mm.
Is it the intent of this challenge that we should strictly use the exact “50mm equivalent lens” for our format or that we should use a “normal lens”? The latter seems much more sensible to me, and if that is the case, then my 28mm lens should be fine on my D3200, and @STM should be able to use 55mm on any of his 35mm film cameras.
In the former case, count me out. Let me know, and I'll simply go back and delete the one posting that I made submitting an entry to this thread, and sit it out; hoping that next month's challenge won't be be based on so stupidly arbitrary and rigid a parameter.
It's possible that I may have to withdraw that entry anyway, as there's another complication that I just realized. Although I used what I insist is a perfectly legitimate “normal lens” for my camera, I cropped the resulting image down to what I thought made a better composition, which has the same effect on the whole image as having used a longer lens. It would take more calculations than I feel like doing right now, but I very much suspect that the net result of cropping on the image that I submitted is that it is now the equivalent of one taken by a lens longer than is considered “normal”. Unless the rules allow this, I would probably need to set the shot up again, and take it, in such a manner as to get the scale and composition I want in the full frame, without cropping it down after the fact. I'll do that, if necessary, if you're going to allow any “normal lens”, but if you're going to insist strictly on “50mm equivalent”, then I'm not going to bother.
I think we need to stop and clarify what the actual parameters are of this challenge.
I interpret the initial description to mean that we should use a “normal lens”.
50mm is nominally considered a “normal lens” for a 35mm camera, hence the name of this challenge. I think it is clear, however, that for anything other than a 35mm camera, of a full-frame FX format digital, that we should use a lens that is of a focal length that is “normal” for the format that we are using.
According to the Wikipedia article on the subject of Normal lens it is most purely defined as being a lens whose focal length is approximately equal to the diagonal measurement of the frame, and approximates the field of view of a human eye. Although 50mm is considered “normal” for a 35mm film frame, the actual frame has a diagonal of √(36² + 24²) = 43.266…mm so that would be the true, purest “normal” lens for this format.
According to the specifications for my D3200, the sensor is 23.2mm ×15.4mm. So, √(23.2² + 15.4²) gives me 27.846…mm.
The Wikipedia states that “For a 35 mm camera with a diagonal of 43 mm, the most commonly used normal lens is 50 mm, but focal lengths between about 40 and 58 mm are also considered normal. The 50 mm focal length was chosen by Oskar Barnack, the creator of the Leica camera.”. For the sensor in my D3200, the equivalent range would be approximately 27.74mm to 37.328mm.
Is it the intent of this challenge that we should strictly use the exact “50mm equivalent lens” for our format or that we should use a “normal lens”? The latter seems much more sensible to me, and if that is the case, then my 28mm lens should be fine on my D3200, and @STM should be able to use 55mm on any of his 35mm film cameras.
In the former case, count me out. Let me know, and I'll simply go back and delete the one posting that I made submitting an entry to this thread, and sit it out; hoping that next month's challenge won't be be based on so stupidly arbitrary and rigid a parameter.
It's possible that I may have to withdraw that entry anyway, as there's another complication that I just realized. Although I used what I insist is a perfectly legitimate “normal lens” for my camera, I cropped the resulting image down to what I thought made a better composition, which has the same effect on the whole image as having used a longer lens. It would take more calculations than I feel like doing right now, but I very much suspect that the net result of cropping on the image that I submitted is that it is now the equivalent of one taken by a lens longer than is considered “normal”. Unless the rules allow this, I would probably need to set the shot up again, and take it, in such a manner as to get the scale and composition I want in the full frame, without cropping it down after the fact. I'll do that, if necessary, if you're going to allow any “normal lens”, but if you're going to insist strictly on “50mm equivalent”, then I'm not going to bother.
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Bob Blaylock
Senior Member
Re: July 2014 Monthly Assignment - Nifty Fifty(ish)!!
1.5 is a number that I often see thrown around, but it's off by a bit, at least with respect to my D3200.
A standard 35mm frame is 36×24 millimeters.
The sensor in my D3200, according to the specifications given on page 196 of the manual, is 23.2×15.4 millimeters.
(√(36² + 24²)) ÷ (√(23.2² + 15.4²)) = 1.553781777…
1.55 is close enough, I think. If I were going to round it to two significant digits, I'd use 1.6, not 1.5.
1.5 is a number that I often see thrown around, but it's off by a bit, at least with respect to my D3200.
A standard 35mm frame is 36×24 millimeters.
The sensor in my D3200, according to the specifications given on page 196 of the manual, is 23.2×15.4 millimeters.
(√(36² + 24²)) ÷ (√(23.2² + 15.4²)) = 1.553781777…
1.55 is close enough, I think. If I were going to round it to two significant digits, I'd use 1.6, not 1.5.
Re: July 2014 Monthly Assignment - Nifty Fifty(ish)!!
I'm not sure what is unclear. 50mm on FX, 35mm on DX, 18.5 on CX regardless of whether you use a prime or zoom. No other requirement.
Yep, exact 50mm equivalent.
Sorry you feel that way - I was trying to do something different. Good luck with next month's challenge.
Never said that cropping wasn't allowed. The idea behind the challenge was to try to get folks out of their routine and maybe get a new perspective by using just a single focal length. I've found when I personally do this it makes me slow down and focus on composition a bit more. The challenge also isn't limited to a single subject so I expect that we'll see some pretty creative results!!
I'm not sure what is unclear. 50mm on FX, 35mm on DX, 18.5 on CX regardless of whether you use a prime or zoom. No other requirement.
Yep, exact 50mm equivalent.
Sorry you feel that way - I was trying to do something different. Good luck with next month's challenge.
Never said that cropping wasn't allowed. The idea behind the challenge was to try to get folks out of their routine and maybe get a new perspective by using just a single focal length. I've found when I personally do this it makes me slow down and focus on composition a bit more. The challenge also isn't limited to a single subject so I expect that we'll see some pretty creative results!!
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Gosh darn it! I just bought a 20,000 dollar 50mm f/0.00000001lens just to win this contest. Now I'm gonna hafta throw it in the garbage.
$20k you say? Don't toss it... mail it! (to me)
LOL
Re: July 2014 Monthly Assignment - Nifty Fifty(ish)!!
No good deed goes unpunished. :sorrow:
No good deed goes unpunished. :sorrow:
We need a forklift.
Re: July 2014 Monthly Assignment - Nifty Fifty(ish)!!
No Mistake, the difference the focal length makes is just the angle of view. A 50mm lens on a D5100 is equivalent to 75mm on Full Frame (FX) which is very close to an 80mm lens on FX and is typically used for portrait work. So you can quite happily use your 50mm for that type of shot.
No Mistake, the difference the focal length makes is just the angle of view. A 50mm lens on a D5100 is equivalent to 75mm on Full Frame (FX) which is very close to an 80mm lens on FX and is typically used for portrait work. So you can quite happily use your 50mm for that type of shot.
Slipperman
Senior Member
ok, i still have a problem here. thinking about it i realized yeah, i can use my 18-140 zoom set at 35mm but what about the aperture? that lens has a minimum setting of 5.6 - a lot higher a value than 1.8. since one of the advantages of using a prime with a wide-open aperture (and i'm pretty sure one of the points of this assignment) is the ability to get really nice bokeh in the background, isn't it a bit unfair to make us use a not as appropriate lens just because of semantics? it puts us at too much of a disadvantage. imo, if i have a 50mm prime that is from Nikon and works on my camera, i should be able to use it regardless of whether it's DX or FX or XXX. the assignment says 50mm. that's what i have.
I appreciate your feedback but the intent of the assignment wasn't bokeh but field of view. The assignment rules were clear that a 50mm FX or DX/CX equivalent was the basis of the assignment. The assignments are supposed to be fun and challenging. You have the tools to be successful and create awesome images that meet the criteria!
Slipperman
Senior Member
well ok, if you put it that way..
Dhopper71 posted a submission taken with a DX lens at 35mm f/8 (reply #13 on page 2). It has some blurred bokeh (and post editing has the ability to further blur backgrounds). The key is to stay far enough away from your background while shooting with a shallow DOF--that will make it blurrier. As his submission shows, you can get some bokeh at f/8. His photo would have had even more bokeh if he used f/5.6.
I see the benefit of this type of challenge. Years ago I read a book by Bryan Peterson where he did individual chapters for wide, normal, and telephoto lenses. It was to get people to use one lens and learn how to really see with it. Perhaps look online to find sample photos taken with specific camera/lens combos--hopefully it will give people some ideas.
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