Depth of Field Adapter on Steroids

ProfHankD wrote:

ProfHankD wrote:

Although I'm not really thrilled about camera obscura-based adapters (I've built more than a few before), I can see there is some interest in an extreme bokeh adapter, so I just ordered parts for making one that should be a very easy build. The tentative name for it is Faboky (pronounced fah-bow-key).

If this works, the total build cost should be less than $150 using only commodity components, including an (optional) integrated 20MP Canon PowerShot programmed using CHDK. No exotic old lens nor other hard-to-source components are needed. As a whole, the camera would provide a zoom setup with DoF equiv. to less than f/0.5 and virtually perfect bokeh because the "a" stands for apodized. It also should be relatively portable and lightweight (note: I didn't say small), although you'll probably need to use it on a tripod. We'll just have to see if this works as well as I think it will; right now, I'd give it about 75% chance of having sufficient image quality.

This is a bit of a distraction to the too-many-other-things I'm already doing, so it might be a while before I have something detailed up on Faboky...

I honestly doubt this will resolve anywhere near 20MP, but preliminary tests are good. Here are the preliminary specs:

• 4:3 aspect capture with 20MP sensor
• Effective FF equivalent focal length of about 68mm
• Effective FF equivalent aperture (for DoF) of about f/0.38
• Contrast is fairly low, flare on bright point sources is a bit wild
• Total weight around 600g (without camera)
• Arca swiss compatible mount (now that I have a fleet of tripods with Arca mounts, I'm putting these on nearly every device I design )
• Total cost is about $20 without camera (using all new materials, including lens)

The big problem is the choice of integrated (yet removable) camera.

Thus far, Faboky is nominally designed for the Canon PowerShot ELPH 180 , which only weighs about 125g and uses a 20MP CCD. I paid around $100 for each of mine new, but it is discontinued and currently available new for an insanely high $350! It seems Canon has recently stopped making all their CCD-based PowerShots, and their HS (High Speed == CMOS, now actually BSI CMOS) cameras start around $240 for the ELPH360HS (which is CHDK supported and a viable alternative). The only big advantage to the HS models is that they can shoot 1080 @ 30FPS, while CCDs stop at 720. I haven't tried Canon's BSI CMOS PowerShots, but their older CMOS models were actually much noisier than their CCD models; hopefully, the move to BSI fixes that.

The goal is to make Faboky work for most of the ELPH models listed on the CHDK Wiki , many of which eBay for under $30. One of the Sony RX100 models would also be viable, but they are overkill, and the CHDK support for the PowerShots really makes the IQ perhaps even slightly favor the PowerShots.

It would certainly be possible to use a larger camera, such as a mirrorless body, in the same way. However, body and lens shapes and sizes vary wildly, making it hard to accommodate many different models, and there's really no benefit except improved video modes.

I also might be able to make a CLIQ printing camera work with it, but that will require some tweaking and testing. Close focus is an issue with CLIQ2. That said, the low resolution of the CLIQ prints would be a good match for this type of device... a very Lomo-ish combo.

So, the question is: Does targeting cheap, but discontinued, PowerShot ELPH models make sense for Faboky?

Yes, and no. Will the camera use a ground glass? If so chances are the resolution is already really limited. In this case, using and adjusting for a used cell phone could be revolutionary in the sense that would allow instant posting of these images and be a sensation. I think chances are some very popular android model would work well, one of those brands will larger sensors, which will make the rig very cheap, then open up possibilities for others to create apps for it, eg. live streaming video, adding a mic, etc.

Them, a later model could move to M43.

I think the discontinued cameras are a dead end. What will happen is the rig is liked by many, will make some hoard these old cameras. Not ideal, but definitely would be fun to watch, and a great case study for an economics course in supply/demand.

What the camera has is insane f-equivalent. Just earlier today I was experimenting with my new 4x5 and taking pictures of the ground glass. The A7RIII gets the shape and microdetails of the ground glass as well as the very fine contour of the fresnel lens. Not necessary at all. 6MP GOOD MP would be more than enough. It's the bokeh, not the crisp detail. For crisp detail I use my 70 years old Elmars. But f0.38? Either simulated or a rig like this. There's no other way.