D7100 W/new lens 24-70

[marcantel]

<p>I just took the plunge and ordered me a Nikon 24-70 2.8G.I'm Going to use it on my D7100.My question is will the 24mm on the Dx be a true wide angle 24mm or will it be cropped like a 29mm or 31 mm etc.</p>

[Jochen_S]

<p>A 35mm on FX would be a true wide angle and your 24mm on DX will be cropped to something like that FOV. - Not really wide, but nice to have.</p>

[pete_s.]

<p>Anything wider than a normal lens is a wide angle. The normal lens on D7100 (DX) is actually a 28mm. The normal is defined as the diagonal of the sensor.<br /> Normal on full frame (FX) is 43mm, closest standard lens being the 50mm.</p>

<p>So yes 24mm on DX is a wide angle but not very wide. Many call this a medium wide.</p>

<p>On full frame I don't find it common to refer to 35mm (or even 28mm) as wide angle lenses. It's not what people go out and buy when they want something wide. Usually that is reserved for 24mm or wider.<br /> <br /> On DX that would translate into 16mm or wider. So if a "true" wide angle lens is what people normally refer to when they say wide angle then the 24-70mm on DX is NOT a "true" wide angle.</p>

<p>On FX:<br /> Normal: 50mm<br /> Medium wide: 35, 28<br /> Wide: 20, 24mm<br /> Ultra wide: 18 or wider</p>

<p>Divide by 1.5 to get the focal length needed on DX.<br>

On DX:<br /> Normal: 28, 35mm<br /> Medium wide: 18, 20, 24<br /> Wide: 16mm<br /> Ultra wide: 14 or wider</p>

<p>On DX the Tokina 11-16mm f2.8 is an ultra wide to wide zoom. Nikon 10-24mm is an ultra wide to medium wide zoom. Nikon 14-24 would also go in this category.</p>

 

[pete_s.]

<p>PS. The 14mm is arguably not an ultra wide on DX. It's the same as 21mm so it's wide for sure but perhaps not really ultra wide as I mentioned above.</p>

<p>Of course there are no real definitions where the limits are between ultra wide and wide. I think in general it is marketing speak. Nikon probably called their first 21mm lens a super ultra wide. But when they had a 14mm lens as well 20 or 21mm, didn't look that wide anymore.</p>

<p> </p>

[pete_s.]

<p>Actually I found a definition stating that ultra wides are lenses with a shorter focal length than the shortest side of the frame. I'm not sure I agree though.</p>

<p>That would put anything wider than 24mm on FX into ultra wide category, and also anything wider than 16mm on DX into ultra wide.</p>

 

[Wouter Willemse]

<p>Focal length as specified on a lens is its focal length. Doesn't change. The format of the camera defines the angle of view for any given focal length (whether it's DX, FX, Medium format or m4/3rd). It's the angle of view that matters - as that is how wide a shot will look.</p>

<p>So, if you insist on calculating back to the corresponding angle of view on 35mm film, you ALWAYS need to apply 1,5x factor for your (DX) camera. For <em>any</em> lens with <em>any</em> focal length, no exceptions. Always.<br /> Of course, in reality there is not much use in calculating back to 35mm film, just look in the viewfinder, see what you get and it all makes sense. The whole "crop factor" thing seems to confuse more than it really solves.</p>

[pete_s.]

<blockquote>

<p>Of course, in reality there is not much use in calculating back to 35mm film, just look in the viewfinder, see what you get and it all makes sense. The whole "crop factor" thing seems to confuse more than it really solves.</p>

</blockquote>

<p>Of course there is. You tell me if a 5mm focal length on a 1/3" sensor is wide or not? Or you want to buy it first and then check?</p>

<p>Converting back to equivalent 35mm film focal length makes a lot of sense. It allows you to compare different lenses on cameras with non-full frame sensors. And that is why every camera which has a fixed focal length states the 35 mm film equivalent focal length of the lens. It's even in the CIPA guidelines.<br /> <br /><em>2 – c ) “Conversion of focal length of DSC lens into 35mm camera equivalent”</em><br /><em>The focal length of a DSC lens converted into that of 35mm camera lens which has the same</em><br /><em>input field angle as the DSC lens.</em><br /> <em>Rules for notation</em><br /><em>a) “Converted into 35mm camera” or similar wording should be noted.</em><br /><em>b) The value is to be calculated using the following equation;</em><br /><em>“Converted focal length into 35mm camera”=Diagonal distance of image area in the 35mm camera (43.27mm) / Diagonal distance of image area on the image sensor of the DSC × focal length of the lens of the DSC</em><br /><em>c) All of the numerical values can be rounded off to two decimal places.</em><br /> <em>Example of notation</em><br /><em>a) “Focal Length : 7mm (Corresponds to 50mm in 35mm camera)”</em><br /><br /><br /></p>

[Wouter Willemse]

<p>Pete, the problem with P&S is that sensor sizes aren't clear, and can vary rather a lot. having some point of reference there, sure, makes sense. That's where the CIPA guidelines no doubt enter. But while zooming, most of these cameras also do not report any type of focal length, just how much you've zoomed. While here, we're talking about systems where you have a lot more information at your disposal to understand what is what.<br>

For systems where the sensor size is a clear given (Canon APS-C / all other APS-C / m43rd / 135 / 120 / etc.), where you can see your focal length, I really do not see the importance of recalculating the "equivalent" focal length to another format (which is relatively arbitrary too, and especially for camera systems that do not use 3:2, like 4/3rds or MF) that you might not be using. The diagonal of the sensor (that CIPA tells to use) actually won't fully correspond to the angle of view either horizontally or vertically, so it's not even all that accurate either.<br>

All the explanation on what is very wide, moderately wide etc. Just look through the viewfinder with the lens you do have (18-105VR, or 18-55VR, some lens will be there) and learn to realise what 18mm, 24mm and 35mm look like <em>on your camera</em>. It's vastly more useful than trying to understand what they'd look like on another camera you do not use. In the end, you need to know what <em>your</em> lens does on <em>your</em> camera.</p>

<p>But well, for the OP: the 24-70 on your D7100 will give the same view as a 36-105 would on a full frame DSLR or a film SLR. Moderately wide to moderately tele.</p>

[pete_s.]

<p>Wouter, angle of view is actually measured diagonally unless specified otherwise so the CIPA calculations are correct in that sense.</p>

<p>If you ever only shoot one size of sensors then sure, forget everything about crop factor or equivalent 35mm focal lengths.</p>

<p>But if you want to be a well rounded competent photographer and being able to shoot different formats and pick appropriate lenses then you need to know how this stuff works. It's the same as understanding aperture, shutter speed and ISO. You don't have to understand it - you can just spin the dials until the image looks good. But we all know it makes life a lot easier in the long run.</p>

<p> </p>

[Wouter Willemse]

<p>Pete, I guess we disagree then. For me, focal length is just there to remember the angle of view - it's the mental projection of this angle that I need to be able to pre-visualise my shot.So, all that matters (in my view), is knowing how a certain FL looks on <em>your</em> camera.<br>

I've shot multiple formats, and frankly, I never needed to know that my 24mm would look like 35mm would look on the other one - I only needed to know how that specific lens would render on that specific camera. And with experience, I knew, and I still know which lens to grab. Implying that I'd not be a rounded competent photographer, able to use different formats, because I find it irrelevant to multiply things by 1,5 is stretching things more than a bit.<br>

Different points of view. Bad pun.</p>

[Peter_in_PA]

<p>Danny, the simple answer is that on your D7100 that lens will be cropped. If you are asking that question on a forum, it probably means you're not a pro. If you are used to 35mm film, that lens has a field of view equivalence of about 36mm (not really very "wide angle" at all) to 105mm (short telephoto). It may work for you. It wouldn't work for me.</p>

<p>The answer to the question that you're not asking is this. If you are going to use that camera for a while, and want a good "standard zoom" that goes from wide angle to short telephoto, you have not chosen the best lens. Send it back.</p>

<p>If you tell us what you already have, perhaps we can make recommendations, but if you're looking for something that goes from wide to short tele with a fast aperture, there's the Nikon 17-55 f2.8 DX (which has been around a while and may be an excellent deal used), or there are 17/18-50 lenses from Sigma and Tamron with f2.8 (and some kind of VR) that may suit you better.</p>

[alan_olander1664878205]

<p>The 24-70mm on a D7100 will have the same field of view as a 36-105mm lens on a full frame camera (FX). That's slight wide to short telephoto.</p>

[chuck]

<p>I am a little surprised you would take the plunge and buy a $1800 lens without a clear idea what coverage the lens offers on the camera you would use. I think the most crucial attribute of the lens is its coverage, maximum aperture and optical performance (within reason) ranks distant second and third.</p>

<p>The 24mm end of 24-70 will always be a true 24mm, regardless of which camera you put it on. It will also always cast the same sized image. But depending on the camera, the sensor will either take the most advantage of size of the image the 24-70 would cast, or it won't. With D7100, it won't. It will take the center 67% or so of the image the lens cast. At 24mm, the lens would still cast an image which would cover a very wide field of view. But the D7100 will only use the center ~67% of it. So while the lens would still be very wide, what the D7100 can see through it won't be very wide, just moderately wide.</p>

<p> </p>

[craig_shearman1]

<p>I used a 24-70 on my D7000 every day. Yes, it crops to the field of view of 36-105, but that's fine for my purposes since in film days I had a 35mm wide angle and 105 portrait lens. Whether it works for you depends on what you shoot.</p>

[pete_s.]

<blockquote>

<p>Implying that I'd not be a rounded competent photographer, able to use different formats, because I find it irrelevant to multiply things by 1,5 is stretching things more than a bit.</p>

</blockquote>

<p>Wouter, sorry if I offended you but I didn't mean you. You obviously know how this all works.<br /> <br /> I mean knowing how focal length and crop works is "needed" in the same manner as knowing how aperture, shutter speed and ISO works. <br /> <br /> I don't mean you have to use it day to day but if you shot a D7100 and liked how the 50mm looked on it, you should be able to pick the equivalent focal length for your new D750 camera. It's not that hard and there are a gazillion places on the net that shows how it works.</p>

<p>Contrary to you I think in equivalent focal length. When I pick up my phone I know it has a 28mm lens (35mm equivalent) so I know exactly what will be inside the frame depending on my distance to the subject. When I put my 50mm f1.2 Nikkor on a GH3 m43 camera I know it will be just like a 105mm on FX. </p>

[ShunCheung]

<p>Danny has a very simple, basic question. Could we all please keep the answer simple as well? I would appreciate everybody's cooperation.</p>

[pete_s.]

<blockquote>

<p>Danny has a very simple, basic question. Could we all please keep the answer simple as well? I would appreciate everybody's cooperation.</p>

</blockquote>

<p>OK, then the answer is NO.</p>

[richsimmons]

<p>The simple answer is no. A 17-50mm Tamron/Sigma would give you a 25.5 to 75mm FOV. I also use a Tamron 10-24mm (15-36mm FOV), which is quite wide, I think, on my D7100. At f/5.6 to 8 it's a very nice landscape lens and sharpens up very nicely. </p>

[eric_arnold]

<p>24-70 on DX = 36-105 equivalent. a useful focal range as the 1.5x crop now extends into the portrait range (70mm on FX can be a little short), but not really wide angle -- i'd suggest getting a dedicated wide lens like the new tokina 11-28/2.8 to cover this.</p>

[Javier Gutierre]

Danny,

What will be your primary use for the lens? 24 on a crop body happens to be my favorite focal length.

[JayWood]

Thank you Shun. Always multiply the focal length by the crop factor to arrive at the 35mm equivalent.

 

This equivalent is the standard by which you can generally level the comparisons among lenses and cameras. You

should also apply the factor to aperture with respect to depth of field.

[Two23]

<p>I have a D7100, and no way I'd be happy if my widest lens was 24mm on that. You might consider adding something wider in months to come.</p>

<p>Kent in SD</p>

[marcantel]

<p>Thanks guys all of you had a lot of Info I bought the lens because of the reviews.I had the tamron 17-50 2.8 and sold on ebay to buy this one.I'LL just have to back up to get that crop in. The tamron lens Is not a quality lens like this nikon 24- 70. I think I'll enjoy it for the broad <br>

range of photos I shoot . Again thanks guys.It was discussion for a science class.</p>

<p>I </p>

[Peter_in_PA]

<p>I'll bet the Tamron was a better lens for that camera, though, and I'll bet that few can tell the difference between photos shot with them. If you rarely went wider than 24 on your Tamron, you'll be happy, but if you found yourself zooming all the way out often, you won't.</p>

[Two23]

<p>I too look at lens performance charts, but the reality is if you're not using a tripod, there just isn't all that much difference in how sharp a lens is. In the end, sharpness comes more from a tripod (and shutter speed if subject is moving.)</p>

<p>Kent in SD</p>