Well I guess we'll have to agree to disagree on the exact severity of it, I just feel that it is best taken on a case by case basis, depending on the equipment being used rather than wrapping up far beyond what you need to, or being so far away that you don't get the shot you are looking for, when it can be taken at an acceptable risk level.
Caution is always better than uneeded risk, I thought my first few posts were pretty much SOP(cover up, minimize overall exposure for camera and self) Just that it is not quite as instantly hazardous as is sometimes made out.
I also stated the exposures my camera has been used for, with a polarizing filter in place.
It was mostly the additional layers of dark welding glasses behind the viewfinder that I'm not so sure are entirely needed.
Tried it once, couldn't get a good shot, could hardly see through the viewfinder.
I do prefer precautions where possible(like polarizing filters, and covering the camera body/hands with something natural)
However, I would not be wearing that dark a tint with additional glasses as well if I was welding 16 gauge sheet. So I think there is nothing wrong with balancing precaution and ability to get the picture you want.
Yes UV is dangerous, yes there are potential long term side effects if you get too much of it, and caution is always best. In most cases with the kind of equipment you find in home shops, it is not quite extreme enough to require multiple layers of equipment, and extra dark shielding behind the viewfinder as well with filters etc in place.
I can only say that in my experience I have not experienced any serious, or severely damaging effects, and I've been working with and around welders for the last 8 years off and on.
I have seen people get sunburn from welding for too many hours without a coat, but certainly not in short doses, and from that far away. I have had some minor discomfort (as you said, like sand) once or twice, due to someone starting a new bead while I was still adjusting what we were working on.
Prescription glasses DO cut the UV, not completely of course, but better than nothing, and better than no protection at all because it was getting in the way. My welding instructor frequently wore those or clear safety glasses rated for normal UV levels while teaching, not suitable for staring at an active arc, but he found them adequate for reflected light if there was a gap in curtains etc as did the students, or if someone hit a table while he was talking. He's been welding for about 45 years(retired except for the one course a year) I tended to wear some slightly more tinted polarized lenses, on before I walked in, and off only after leaving but I was welding all day then.
I am not saying go and stand nude around a welder, or stare into it, just that it is possible to minimize risks and still get the shot you want, without big lobster mitts, a full coat, additional welding tinted glasses and a mask behind the viewfinder etc.
overexposure to the sun will also give you skin cancer, and reddened skin too.
No it is not the same as perfect PPE,
but as a photographer, you would not be exposed the same way as someone working 40 hours a week with a welder.
if you are comfortable with additional kit, then I would go for it, and certainly in the higher exposure risks(like welding AL).
Some common sense precautions(long sleeves, natural fibers, some form of safety glasses, even better with a reasonable tint(yellow or light green) is quite sufficient in most cases for taking a few pictures.
There are once in a million injuries like the one about the reflected UV off a window(one I saw recently was someone blowing their thumb up full of air because of a small cut, despite having done the exact same steps for over 25 years, if I hadn't seen it in person, I never would believe it, it took us a lot of work with a syringe to suck most of the air out before it could go anywhere else in him and then a trip to the ER to get it sorted)
I would be curious about what type of equipment was being used when the blindness from a window reflection occurred. I would bet it was more than a regular MIG/TIG setup in a small shop. If not, then I am very surprised.
Back on the topic of the picture, I like the balance of seeing the welders hands, but no faceshield, and the orange of the gloves with the glow through the metal. Do you have any more pictures from that?
What was your friend working on?