pennet_smith

<p>It's not the fact that there is that jag or that the blades don't line up and you see the rounded tips of the aperture blades that drove my crazy. It's the fact that it's uneven. WHY NIKON?!?!?! lol, I don't really care if the lens is designed like this... everyone touts its legendary performance, I just thought it was a defect. </p>

<p>I spoke to someone else too who said they had their lens repaired and rebuilt by Nikon because the back element was scratched and the focal column was sticking due to drop damage, and he said he got a totally rebuilt lens back that looks the same.</p>

<p><img src="http://i.imgur.com/pNZXRzN.png" alt="" width="1063" height="849" /><img src="http://i.imgur.com/riP2hms.jpg" alt="" width="1178" height="915" /></p>

<p>Plus I've found photos where people got the same lopsided bokeh from the aperture. It's jagged on one side and round on the other.</p>

<p><img src="http://farm3.staticflickr.com/2264/2363875345_775108dcc0_b.jpg" alt="" width="1024" height="681" /><br>

<a href="http://farm3.staticflickr.com/2264/2363875345_859e736610_o.jpg">Full size image here</a></p>

<p>I've spoken to some other 28mm f/1.4 D owners recently and they've all said that their lens looks the same. Still haven't been able to get a photo to compare though.<br /> I did find <a href="http://www.dpreview.com/forums/thread/2203911">this post though.</a><img src="http://terpconnect.umd.edu/~natkuhn/photos/080102/slides/IMGP8436.JPG" alt="" width="752" height="500" /><br /> Where someone was asking if his lens on the left was normal, and people said yah it was designed like that. So it looks like some lenses are designed like this.</p>

<blockquote>

<p>I think it`s a common problem in some lenses</p>

</blockquote>

<p>I'm mostly wondering if the 28mm f/1.4 was designed like this (not if it's a problem) or if just mine is a defect. That's why I originally posted a photo of the 50mm f/1.2 as it was the only other lens I could find with a similar diaphragm.</p>

<p>The first two photos someone sent me showing their lens, but they only have shown me the back. So I took similar photos of the back of my lens. <br>

<img src="http://i.imgur.com/CFR6Pp1l.jpg" alt="" width="426" height="640" /> <br>

This one is his<br>

<img src="http://i.imgur.com/1EHaJCrl.jpg" alt="" width="577" height="640" /><br>

This one is mine.<br>

I put arrows in front of, going clockwise, the "steps" that I am talking about. Both of us have bigger steps between the blades near the top and smaller steps near the bottom between blades. <br>

I'm still trying to find someone who can provide a shot of the front of their lens <a href="http://i.imgur.com/h01JYe4.jpg">like this</a> to compare between the two. To me, especially in the second and third frame, it seems like one side of the aperture is opening at a different rate to the other side of the aperture.</p>

<p>I found some shots someone else took of the same lens online. My guess is the first one is at f/1.4<img src="http://i994.photobucket.com/albums/af66/kaoquan/Nikon%2028mm/IMG_8999_zpse6788913.jpg" alt="" width="682" height="1024" /><br>

and the second one is at f/2.0 (or the first one is at f/1.8 or f/2.0 and the second one is somewhere around f/2.8)<br>

<img src="http://i994.photobucket.com/albums/af66/kaoquan/Nikon%2028mm/IMG_8998_zps26a99728.jpg" alt="" width="682" height="1024" /><br>

I know this setup is probably too inaccurate to test but here are some similar shots I took of mine.<br>

<img src="http://i.imgur.com/ype3X6kl.jpg" alt="" width="577" height="640" /><br>

<img src="http://i.imgur.com/M9Txy33l.jpg" alt="" width="638" height="640" /><br>

<img src="http://i.imgur.com/qsCNVbhl.jpg" alt="" width="640" height="619" /><br>

<img src="http://i.imgur.com/GAWcMM0l.jpg" alt="" width="626" height="640" /></p>

<p>& fully open<br>

http://i.imgur.com/69NOEujl.jpg<br>

& at f/4.0<br>

<img src="http://i.imgur.com/YgX655Sl.jpg" alt="" width="545" height="640" /><br>

The problem is not that noticeable at f/1.4 but still present, it shows the most between f/1.6, f/1.8, f/2.0, f2.2, f/2.5 and f/2.8; still a little bit at f/3.2 and minor to not at all at f/3.5 and onwards.</p>

<p>Mostly I'de just really like to find someone with the same lens that I can compare with to see if this is a defect or if the lens is meant to be this way. It makes me wonder as on mine there is a huge step between the blades on the top compared to on the bottom. I also tried phoning Nikon repair but they're not open until Monday. I have a feeling they won't repair this one if it is defective or won't know about it anymore as it's a discontinued lens. </p>

<p>I am sorry I used one of his photos, but I could not find anything else that displayed a similar issue. I've now found a different example and will update that post.</p>

<p>Also, I've taken photos of <a href="http://i.imgur.com/h01JYe4.jpg">my iris blades</a>, and yes I put my camera on a tripod for this and shot straight down at the lens.</p>

<p>---edit---<br /> okay, I don't seem to be able to edit my first post and remove the Ken Rockwell photo this was what I was going to include in place of it. In <a href="http://www.youtube.com/watch?v=6F6oj1OP19Y">this video</a> you can see blades working right @0:15, and they seem to have the same step, but they don't seem to be off centre like mine are where one side is closing faster than the other/at a different point in it's opening.</p>

<p>Hello all, (sorry in advance, my images in question are just linked. They're high resolution so you can see in detail the problem I am talking about. It didn't make sense to downsize them so the forum could display them as you'll need to see the full resolution ones anyway, so I just linked those)<br /> I got a new lens recently, a 28mm NIkon/Nikkor f/1.4D, and it's been great, but a friend of mine picked up on something that might be a fault with it. I am interested in input from both people knowledgeable with aperture blades as well as this lens specifically. My friend seemed to think that it was odd, but probably just how the lens is built and I would like to compare it with one of its siblings.</p>

<p>First off, he noticed that something was off with the aperture blades</p>

<p><a href="http://i.imgur.com/QWqZgoD.jpg">Click for full sized image #1</a></p>

<p>and we saw it in the bokeh</p>

<p><a href="http://i.imgur.com/9e3Sfkq.jpg">Click for full sized image #2</a></p>

<p>at f/1.4 it's not so bad</p>

<p><a href="http://i.imgur.com/HOZBquw.jpg">Click for full sized image #3</a><br /> <a href="http://i.imgur.com/IC97vli.jpg">Click for full sized image #4</a></p>

<p>but it starts to get bad near f/1.8 (I would even say f/1.6) and is really bad at f/2.0, after f/3.5 it's totally fine.</p>

<p><a href="http://i.imgur.com/eAWkyOf.jpg">Click for full sized image #5</a></p>

<p>You can see in the top left, that you're not just seeing the steps/layers of the aperture blades. It seems like one side isn't closing correctly >_< I have a 50mm f/1.4 D as well and that has no problems whatsoever</p>

<p><a href="http://i.imgur.com/TkZMyBA.jpg">Click for full sized image #6</a> (I wrote on the photo that it's an 8 blade lens, that's wrong; it's a 7 blade)</p>

<p>Never do you notice a step when looking at the blades, and the Bokeh is always really round.<br /> Now I know that the 50mm only has 7 blades, but I heard that 9 blades like what is in the 28mm was meant to produce a more round bokeh.</p>

<p>Does anyone think this is a problem with the aperture blades themselves or can anyone with this same lens confirm that this is just infact how this lens is constructed and it is meant to be like this? When looking at other 9 blade lenses like the 50mm f/1.2 it does look like it has a bit of jag/the blades don't produce a totally round hole, but the movement/opening doesn't seem to as off as mine where the blades seem to be at different points on their track.</p>

<p><img src="http://i.imgur.com/WSmFdQC.png" alt="" width="460" height="461" />image #7</p>

<p>The bottom only looks slightly more closed than the top but you can still see a difference as the top looks more open than the bottom. Is this just a thing 9 bladed lenses do as a consequence of having so many blades laying on top of each other and competing for room? It'de be cool to see photos of your aperture blades (of the same 28mm f/1.4 D lens) and your bokeh photos to compare. I live in Canada and I'm debating sending it to one of the Nikon repair centres to have it fixed if it is really a defect. I'm going to try contact them in the morning too when they're open.</p>

<p>(Also when you reply, I'de appreciate it if you use the image #s so that it's clear which examples we're referring to.</p>