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Decapping and Chip-Documentation - Howto

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magic:
People have been using webcam, smartphone and similar lenses for macro photography for many years. I think they work well because in their normal use they need to support very high pixel densities on the sensor side. The webcam I converted has ~3µ pixels and low resolution (1280x1024) so if the lens limited it further, the problems would be quite visible and one couldn't hide them by scaling down since even full resolution doesn't really fill a modern screen.

Or maybe I just got lucky with mine ;D If anyone wants to know, it's Esperanza EC105, which appears to be a Polish company that sticks their logo on random Chinese stuff, so it may be available under different names elsewhere. I think any of those big, "cannon style" webcams with similar lens and HD or better resolution is likely to work.

The sensors on those things aren't great, though. One reason I picked the M42 system was to have a path for potential upgrade to better cameras, up to a MILC.

Another missing piece is a system to automatically move the die under the camera, so that even large dice could be "scanned" with little effort. Hugin is working reliably so far, so stitching a 1000 frame mossaic would hopefully only be a matter of waiting an hour for the result.

Noopy:

--- Quote from: Noopy on July 28, 2021, 04:53:13 am ---- 100-400mm 4,5-5,6 AND 10-22mm 3,5-4,5 => huge magnification but due to diffraction probably not ideal
- 100mm 2,8 AND 10-22mm 3,5-4,5 => better quality than today?
- 100-400mm 4,5-5,6 OR 100mm 2,8 AND 35mm 1,8 => I wasn´t happy with the 35mm 1,8. Perhaps stacked it gets better.
- I have a nice 24-70mm 2,8 perhaps I will try that too. Probably as second lens because 70mm seems to be a little short for the first lens.
- Would it make any sense to stack the MP-E 65mm 1-5x? No, probably not...

--- End quote ---

I think I was quite lucky with my 10-22mm retro. I didn't get much better picture quality with the other combinations.

100mm stacked with 10-22mm was slightly better than 10-22mm retro without the 100mm but not very much. Besides that this combination gives me just a magnification of 10x and it is less handy.  :-\

The stack 400mm - 24mm was huuuge.  :o It looked very funny and expensive. Sorry, no picture. Imagine a "Canon 100-400mm 4.5-5.6 l" zoomed to the maximum stacked with a "Canon 24-70 2.8 I" zoomed to the maximum (invers zoom).  ;D
A magnification of 17x seemed to be good but the image quality was bad. :'(

magic:
10x magnification doesn't seem too bad. It's ~6px per minimum resolvable point distance at 550nm if I'm not mistaken*, probably near the reasonable minimum for comfortably avoiding sensor bottleneck.

The f/1.8 would be nice but even more magnification is needed to really take advantage of it on APS-C. It's not gonna be easy with f=35mm. That's a setup that would look PRO :wtf:

*calculations specific to EOS 60D with f/4 lens, of course

Noopy:
10x magnification is quite ok but I personally need more!  :-/O ;D

magic:
More magnification or more resolution? :box:

Here's an interesting discovery: if 10x is needed to easily recover full resolution of f/4 on a typical APS-C sensor, then a typical 10x0.25 microscope objective (f/2 equivalent) may slightly outresolve such sensor. Same with 5x0.12, 20x0.4 and so on.

I'm sure it makes bug shooters happy, but it seems not ideal for high magnification closeups and getting the most fine detail out of the optics. Testing would be needed to establish the exact limits, including Bayer and anti-alias effects. I suppose blue is the worst case, assuming that you want to take advantage of the short wavelength and capture more detail in blue than in green/red. Red is also affected by 25% pixel density but at least it's blurred more so there is less detail to recover. Some analysis of the problem has been made at PM and linked by mawyatt last year, but it seems mostly theoretical.

Full frame is even worse. You have to buy the highest end to get a mere 45Mpx and the same 4.3µ pixel size.

Nikon 1? :-DD

edit
Alternative kludges are possible. One could try an infinity objective with +2D tube lens on 50cm extension (or 500mm telephoto) to double the magnification :wtf:

These guys don't give a damn and just mount infinity objectives on a super long extension tube and focus them at a finite (but long) distance. However, I am not entirely sure if they know what they are doing and whether their techniques are optimal. The other day, they also identified a bipolar IC which could be some LM386 as a MEMS strain gauge ::)

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