I am working with a program that generates artificial FASTQ files from a given reference genome and it allows for read length customization. I am trying to produce several FASTQ files with different read lengths. Hence, I want to know what read lengths are produced by real sequencers such as those from Illumina. I found [this][1] site which states the maximum read length of some sequencers.

However, when stating, for example, that the maximum read length is 2 x 150 bp, is that supposed to mean that each end of a contig will be 150 bp long? Also, if that is the case, does this mean that the sequencer could be set up to produce read lengths equal to any number of base pairs less than 150? i.e. could the sequencer produce read lengths of 2 x 1 bp, 2 x 2 bp, 2 x 3 bp,...., 2 x 148 bp, 2 x 149 bp? Lastly, which one of those sequencers is the most commonly used for genomes which are about as long as, say, that of E. Coli?

 [1]: http://www.illumina.com/systems/sequencing.ilmn
The read lengths (up to maximum) are somewhat configurable. However, there are some very commonly used lengths that have predominated at different times. In earlier days you would see a lot of 2x36, 2x50, and 2x76 from the Illumina GA or GAII. With the HiSeq 2000/2500 it was most common to see 2x100 or 2x150 (you also often see 2x101 or 2x151). The MiSeqs often produce 2x250 or 2x300. The HiSeq 4000, HiSeq X, and NovaSeq 5000/6000 seem to most often be run at 2x150. I would probably go with 2x100 for your simulations.
