Introduction:

Among DSLR enthusiasts, it seems to be generally known that it is better to spend your money on a good lens than spend it all on a great body. But how far can we really take this principle? Will nice glass actually help the image quality of a relatively cheap Powershot? Take a look at the samples below and decide for yourself!

Before:

After:

Purpose:

To increase the image quality of a cheap and light Canon Powershot by mounting a C-mount lens.

C-mount lenses were used on film 16mm movie cameras originally, but are now used on robots and security cameras because of their small size. Most microscope and telescope camera mounts are also C-mount. Many micro 4/3 enthusiasts have used C-mount lenses with adapters due to their unbeatable price, simple manual controls, and interesting â€˜look.â€™ Recently, a company called Backbone began modifying GoPros and other action cameras, utilizing C-mount traits to acquire a more cinematic look from these camerasâ€™ exceptional sensor. In this experiment, however, we will be utilizing the mediocre sensor of the Canon Powershot ELPH 100 HS.

Procedure:

Note: as with most anything else, please read the whole writeup before trying this yourself â€" there are a couple of fragile parts that youâ€™ll want to know about so you donâ€™t break them in the process.

First, I selected a camera from Ebay and Craigslistâ€™s available options. I didnâ€™t want something too expensive, since I thought I might destroy it, but I also wanted something that would shoot video (preferably at 1080p), so after a while I came across this ELPH 100 HS.

It was only about $10 since the lens was jammed. When it arrived, I cleared the jam and took the stock camera out for some test footage.

https://drive.google.com/open?id=1p05f7czQl5Ke6U-o3I1n2sfjw3PSvlDt

I ended up ordering a Fujian 35mm F1.7 lens after watching some reviews, but I think I may have gotten a knock-off or something â€" the images seem to have a blue distortion around all bright contrasts. Maybe thatâ€™s just how the lens is.
Before getting inside the camera, you should know that the ribbon cables are kind of fragile. Be really careful with how you pull on and fold them. I had to buy two replacement lens units and a new screen because I kept on breaking cables.
When it comes to the actual modification, there are three main challenges to overcome: getting the camera to accept the lens transplant, setting up the shutter assembly, and physically mounting the lens.

1. Getting the camera to accept the lens transplant.

The problem is, the camera has sensors on all its major components, so when it starts up, it kind of â€˜wiggles its limbsâ€™ to make sure everything is ok. If one (or all...) of them are missing, the camera wonâ€™t boot up, showing an error.

There are two ways around this. The first is to disable these checks using the CHDK software. This works nicely for the Image Stabilizer error (which comes up, after a few seconds of use as error â€˜E32â€™), all I had to do was send these commands after switching to/from record mode either by CHDK PTP or with a script (attached below):
call_event_proc(â€œMecha.Createâ€)
call_event_proc(â€œStartImStEventProcâ€)
call_event_proc(â€œDisableISDriveErrorâ€)
More information here: http://chdk.wikia.com/wiki/User:Srsa_4c/Working_with_a_broken_camera

Unfortunately, I was not able to figure out a way around the other errors with software. For this reason, I had to utilize the other method of making the camera happy â€" tricking the sensors. The idea is to leave as much of the moving part as is required to satisfy the sensor.

To satisfy the focus sensor, I broke off the arm that holds the focusing lens, but left the motor assembly to move about freely. Be careful since ribbon cable connecting the focus motor is not very strong!

The Zoom sensor is located on the main lens housing between the zoom motor and the backup battery. The tiny strip running to it is one of those fragile parts of the ribbon cable, so be mindful of what kind of stress youâ€™re putting on it. It is satisfied by a tab located on the main zoom ring that moves through it as the zoom ring turns.

Every other part of the lens can be removed, but this main zoom ring must stay to satisfy the zoom sensor.
When you boot up the camera, the focus motor should move about pointlessly, and the focus ring should rotate a bit, but that shouldnâ€™t affect anything. Just some useless shenanigans to keep the camera happy.