Hyperloop documentation additions for requesting long train (#264)

* Explain changing derived data type of long trains

* Explain changing derived data type of long trains in operator docs

* Add long train derived data type img

Author: nicolaspoffley

docs/hyperloop/operatordocumentation.md

@@ -189,7 +189,15 @@ There are a number of settings that you can decide on when composing a train:
    <img src="../images/cloneTrain.png" width="70%">
 </div>
 
+### <a name="request-long-train"></a>Request Long Train
+
 * <a name="longTrain"></a>The _Request long train_ tab allows users to request a long train after the train ran on a short dataset. Short datasets are subsets of a big dataset (_set up in the Dataset settings_). First, a train run needs to be **Done on a smaller short dataset** before being run on a bigger dataset.
+* When requesting a long train, it is possible to request standard derived data from a short train with slim derived data.
+
+<div align="center">
+   <img src="../images/longTrainDerivedType.png" width="70%">
+</div>
+
 * Any user who is part of the analysis can request a long train. Approval from the participating analyses PWGs conveners is required in order to submit a long train. Train operators or admins can also approve a long train, but it is usually done by the PWG.
 
 <div align="center">

docs/hyperloop/userdocumentation.md

@@ -492,8 +492,16 @@ It is possible that a wagon test will produce multiple warnings. In that case, t
    <img src="../images/mergedOutput1.png" width="90%">
 </div>
 
+
+### <a name="request-long-train"></a> Request Long Train
+
 * <a name="longTrain"></a>The _Request long train_ tab allows users to request a long train after the train ran on a short dataset. Short datasets are subsets of a big dataset (_set up in the Dataset settings_). First, a train run needs to be **Done on a smaller short dataset** before being run on a bigger dataset.
 * Any user who is part of the analysis can request a long train. Approval from the participating analyses PWGs conveners is required in order to submit a long train.
+<div align="center">
+   <img src="../images/longTrainDerivedType.png" width="70%">
+</div>
+
+* When requesting a long train, it is possible to request standard derived data from a short train with slim derived data by changing the derived data setting as shown above.
 
 <div align="center">
    <img src="../images/requestLongTrain.png" width="70%">