# Why does a small change in focal length of two lenses make a $1000.00 difference in the price? I was looking at some lenses and the famous 24-70mm f/2.8G ED AF-S Nikkor Wide Angle Zoom Lens is almost$2000.00. Then, I also found this one: Nikon 28-70mm f/2.8D ED-IF AF-S Zoom Nikkor Lens and this one is less than one grand.

So both of them are f/2.8 but one costs $1000.00 more — Why? This helps me understand what are the important things to consider or actually ignore in buying a lens, too. • Based on those prices, I'm guessing one is new and one is used? That seems an unfair comparison in that regard. – Dan Wolfgang Dec 15 '14 at 11:53 • Tangentially related - the price (x), focal length (y), f/stop (size) graph of Nikon prime lenses from 2006 (when I made that graph): i.stack.imgur.com/Nu5gZ.gif - while there is a trend to it, there are some outliers that can make specific lenses much more or less expensive than others because of the design of the lens. – user13451 Dec 16 '14 at 5:04 ## 4 Answers The focal length/speed is only one factor in the retail price of the lens. Other goodies like construction (metal vs. plastic), image stabilization (and other automation in general) and vintage can easily add (or remove) a zero. The two lenses in the question are very different products. The 2.8G is a newer product and lacks an aperture ring - the diaphragm is controlled electronically. The older lens has internal focusing - the barrel doesn't move. The newer lens also has 3 (instead of 1) aspherical elements, and they are not cheap. Predicted market will be a very large influence - the Canon 1200mm/5.6L sold about 2 per year and cost as much as a small house as a result. In short, price is in no way proportional to focal length. • The 2.8G is a newer product ? or 2.4? I think 2.4 is newer? – Brandon Dec 15 '14 at 14:15 • I think you're confusing cause and effect for the Canon 1200mm. Manufacturing that lens required growing two gigantic, flawless calcium fluoride crystals for the low-dispersion lens elements and just growing those crystals takes months. That makes the lens very expensive to make; that's why it cost as much as a small house and that, in turn, is why few were sold. – David Richerby Dec 15 '14 at 14:17 • I know - I was seeking an extreme example of focal length vs. market vs. price. The crystals could have been mass-produced. – paul Dec 15 '14 at 21:11 AFAIK the 28-70 isn't being produced anymore since 2008-ish? So if you are buying a new one today chances are it's been in somebody's warehouse for at least 6 years burning a hole in their pocket. The new version also allegedly boasts a better nano-coating on the front element. Not sure what else might be making up for the price difference. The AF-S 28-70/2.8D f/2.8 has been out of production since 2007. It's an older version of the lens that's more or less be replaced by the newer 24-70. Nearly every lens that's been superseded tends to cost less than newer replacement models, especially if found used (when it was brand new in 2002, the 28-70/2.8 cost$1400, which if you cost adjust, comes in around \$1850 in today's prices, so it also was not that much cheaper new).

Not only was the zoom range extended at the wide end, but the optical design was overhauled and is not as similar as you might think.

You can find a block diagram for the 28-70/2.8D on mir.com.my (scroll down a ways--it's next to the MTF charts)

Not only does the new lens have one additional ED (extra-low disperson--corrects for C/A) element, it also has two additional aspherical elements. This undoubtedly added to the production costs as well.

• I don't like that these images are ripped from rockwell. Mostly because I don't like him. – dpollitt Dec 16 '14 at 2:42
• @dpollitt should I remove and link instead? I'd prefer not to drive traffic to his site. – inkista Dec 16 '14 at 3:00
• Technically I don't think we should be posting image like this unless they are CC BY-SA(which I have not confirmed if these are or not but I would imagine not) See this for more info: meta.photo.stackexchange.com/a/1725/4892 – dpollitt Dec 16 '14 at 3:03
• @dpollitt Ok. I'll remove and link to a non-Rockwell source. Too bad, though. It's easier to compare if you can see them side by side. And Nikon doesn't put them up on their website. – inkista Dec 16 '14 at 3:05
• @dpollitt you could always get them from Nikonusa.com - 24-70mm (click on 'view lens construction' which brings up the image of cdn-4.nikon-cdn.com/en_INC/IMG/Assets/Camera-Lenses/2010/… -- Ken didn't create those images - he ripped them from either the Nikon documentation or a site that had historical nikon documentation. – user13451 Dec 16 '14 at 5:16

What is difficult is to build a zoom that can maintain a constant aperture as low as 2.8 along the entire zoom range. Those lens has the characteristics that you can shoot at 70mm or 200mm at f/2.8. To be able to do this make a lens expensive. Check for example cheaper lens from Nikon. You will see that changing focal lens (zooming) will change the minimum aperture you can use. The lower the aperture the more light you get, and therefore the faster the shutter speed you can use.

In addition the longer the focal lens the more difficult is to build them and get good quality, constant focal lens, no aberration, etc. Since the longer the focal lens the more glass you have in your lens (usually). Check the price for 300mm or 400mm lens from Nikon. You will see how the price skyrockets!

• While this is mostly true (except the part that those lenses can shoot at 200mm!), it doesn't explain why the 24-70 is so much more expensive than the 28-70 - they've both got the same maximum focal length. – Philip Kendall Dec 15 '14 at 8:41
• But both of the lenses mentioned in the question are contant aperture lenses and they both have the same maximum focal length. – David Richerby Dec 15 '14 at 14:25