petrochemist

There are multiple factors that affect how visible the mesh is. The closer the lens is to the mesh the better The further the subject is from the mesh the better The longer the (actual) focal length the better The wider the aperture the better. With a reasonably long telephoto wide open & touching chicken wire I shot this: The mesh behind the bird is visible but I can't see anything in front. At motorsports there is frequently safety fencing that you can't get close to (or it would provide less protection). Broadly similar settings but around 5 foot from the mesh gave: The mesh doesn't detract too much but it can be seen

I would NEVER go for the best computer money can buy. If you go for one that is merely good (best 2 years ago?) you'll save an absolute fortune, and would be able to upgrade twice as often should you want to (probably not needed). My home computer is actually a 4GB Raspberry Pi 4 which runs a version of Linux & does most of what I need, for under £200 (excluding external drives, but including other peripherals). The 10+ year old laptop I have is now a bit slow but will run any unusual software I want to play with.

No not T-mount, I've heard Hanimex had their own variant adaptable mount. I don't think I've come upon any yet. Perhaps I should double check my Hanimex & Palinar lenses :) FWIW T-mounts are still popular for mounting to telescopes (& to a lesser extent microscopes) but more commonly known as T2 now - I don't think there's any difference in thread or registration officially the T2 allows orientation to be adjusted, but the names seem to be used interchangeably.

Indeed it's what you what you use it for, but it's effect does require the effect to be compensated, or the pond floor will be invisible.

As far as I know there is no such thing as a digital polariser. Newer filters sold for digital may have better coatings but they still polarise light using real light before any digital to analogue conversion. Polarisers themselves can be high extinction or high transmission types, then there is a linear/circular choice depending on if a quarter wave plate is added. It doesn't work well combining two circular polarisers (at least unless you switch one round - two CPLs back to back give very weird effects, front to front they can work like a variable ND). You can get perfectly good results using a 50 year old linear polariser on a digital camera, my grandfathers old 'pile of plates' polariser (probably over 100 years old) would also work if it was a bit wider - less than 1/2" diameter is just too small for my lenses. FWIW circular polarisers came out long before digital photography was practical, yes they work fine with film as that's what they were originally made for! I think my first CPL was brought in the mid 1980's

Usually the effect of the filter is small enough that you don't need to allow for it, but if a significant amount of the incoming light is all polarised in the same direction you may need to compensate if not using TTL metering (self compensating) On occasion I've had reflections from water that provided far more than half of the light. Arrange the polariser one way & expose for the reflection, twist it by 90 degrees & you have to expose for the dim pond floor...

Only if you're using a mirror on a mirrorless :)

There's always macro of items round the house: Watch Macro by Mike Kanssen, on Flickr

I wouldn't call those doughnuts subtle, but the subject is attractive enough to make them bearable! I have taken a few where the bokeh is more distracting, but the vast majority it hardly shows at all.

Reading you first post again I suspect it's actually a 35mm lens designed for 16mm film format. Cine projector lenses frequently have extremely short rear distances and the parts separating could be just a focus mechanism. Removing a group of elements for a lens design often gives another usable lens which typically has uncorrected aberrations - giving rise to your lovely impressionistic results.

Whilst reading your first post I thought it was 16mm format & 35mm focal length, but the two part design does pretty much rule that out. I think formats could easily be the meanings It's very difficult to judge focal length with macro subjects, & projector lenses can have very short rear focal distance (infinity focus probably impossible). Can you estimate the focal length by (unmounted) comparison with other lenses?

A very generous offer Stan. I'd probably find several of them useful, but I'm in the UK so postage would no doubt be significantly higher :(

Oh yes Custom White Balance targets are another one, I tend to forget :)

If I keep secrets it's because I can't remember myself, legacy lenses & filters (I often shot IR so filters are important) can both fall into this category, if I don't note them down quickly.

I've always heard that the longest focal length contax lenses required the Flektoskop, Flektometer or Panflex mounts which add a reflex viewer, effectively turning the rangefinder into a SLR. As well as many printed sources over the years claiming rangefinders were limited to 135mm for focusing reasons (it would take me years to find them) this can be found at Contax rangefinder If this is inaccurate perhaps the Contax, which is often acknowledged as the best rangefinder managed to stretch things somewhat, with really top grade hardware.