<h3 dir="auto">Bug report</h3>
<p dir="auto"><strong>Bug summary</strong></p>

<p dir="auto"><strong>Code for reproduction</strong></p>

<div class="highlight highlight-source-python notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="# 
plt.savefig('Photo.png', dpi=600, bbox_inches='tight')
#"><pre class="notranslate"><span class="pl-c"># </span>
<span class="pl-s1">plt</span>.<span class="pl-en">savefig</span>(<span class="pl-s">'Photo.png'</span>, <span class="pl-s1">dpi</span><span class="pl-c1">=</span><span class="pl-c1">600</span>, <span class="pl-s1">bbox_inches</span><span class="pl-c1">=</span><span class="pl-s">'tight'</span>)
<span class="pl-c">#</span></pre></div>
<p dir="auto"><strong>Actual outcome</strong></p>

<p dir="auto"><a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/42562919/46396899-43cb9b80-c723-11e8-8945-b20be5c52014.png"><img src="https://user-images.githubusercontent.com/42562919/46396899-43cb9b80-c723-11e8-8945-b20be5c52014.png" alt="image" style="max-width: 100%;"></a></p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="# If applicable, paste the console output here
# The output figure can be seen as below:

#"><pre class="notranslate"><code class="notranslate"># If applicable, paste the console output here
# The output figure can be seen as below:

#
</code></pre></div>
<p dir="auto"><strong>Expected outcome</strong></p>


<p dir="auto"><strong>Matplotlib version</strong></p>

<ul dir="auto">
<li>Operating system: windows10 x64</li>
<li>Matplotlib version: 3.0.0</li>
<li>Matplotlib backend (<code class="notranslate">print(matplotlib.get_backend())</code>):</li>
<li>Python version: 3.5、3.6</li>
<li>Jupyter version (if applicable):</li>
<li>Other libraries:</li>
</ul>


<p dir="auto">The output figure file is strange: there is a lot of blank area on the output figure.</p>
<p dir="auto">Calling <code class="notranslate">fig.tight_layout()</code> on a figure with a 3d <code class="notranslate">Axes</code> inside will collapse the axes into a vertical line.</p>
<p dir="auto">Minimal example:</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D

for tighten in False,True:
    fig = plt.figure()
    ax = fig.add_subplot(111, projection='3d')
    ax.plot([1,2], [1,2], [1,2])
    if tighten:
        fig.tight_layout()

plt.show()"><pre class="notranslate"><code class="notranslate">import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D

for tighten in False,True:
    fig = plt.figure()
    ax = fig.add_subplot(111, projection='3d')
    ax.plot([1,2], [1,2], [1,2])
    if tighten:
        fig.tight_layout()

plt.show()
</code></pre></div>
<p dir="auto">The following figures are produced with python 3.7, matplotlib 3.0.0 (also master):<br>
<a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/17914410/45932469-be0a5c00-bf7c-11e8-9988-1bf55e10ced5.png?s=50"><img src="https://user-images.githubusercontent.com/17914410/45932469-be0a5c00-bf7c-11e8-9988-1bf55e10ced5.png?s=50" alt="figure without tight_layout: all's fine" style="max-width: 100%;"></a><br>
<a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/17914410/45932470-c19de300-bf7c-11e8-8368-52e12d0c48cc.png"><img src="https://user-images.githubusercontent.com/17914410/45932470-c19de300-bf7c-11e8-8368-52e12d0c48cc.png" alt="figure with tight_layout: axes is a single vertical line" style="max-width: 100%;"></a></p>
<p dir="auto">There's also a warning that says<br>
<code class="notranslate">/home/user/matplotlib-env/lib/python3.7/site-packages/matplotlib/tight_layout.py:177: UserWarning: The left and right margins cannot be made large enough to accommodate all axes decorations.</code><br>
but that's hardly surprising since there's no room for any decorations whatsoever.</p>
<p dir="auto">May or may not be related to the recent-ish issues fixed by <a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="343440693" data-permission-text="Title is private" data-url="https://github.com/matplotlib/matplotlib/issues/11739" data-hovercard-type="pull_request" data-hovercard-url="/matplotlib/matplotlib/pull/11739/hovercard" href="https://github.com/matplotlib/matplotlib/pull/11739">#11739</a> and <a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="340086265" data-permission-text="Title is private" data-url="https://github.com/matplotlib/matplotlib/issues/11627" data-hovercard-type="pull_request" data-hovercard-url="/matplotlib/matplotlib/pull/11627/hovercard" href="https://github.com/matplotlib/matplotlib/pull/11627">#11627</a>.</p>