Search found 4524 matches

by Lou Jost
Thu Sep 03, 2020 5:59 am
Forum: Equipment Discussions
Topic: Another questionable eBay listing
Replies: 14
Views: 454

Re: Another questionable eBay listing

Chendata sold a 1x lens he called "16k line-scanner", it's an old 8k reproduction lens. Yes, that's the kind of thing I was talking about above with respect to Chendata. Decent stuff but not carefully described. I think he did sell the 3.5x Rayfact but did not say it was 3.5x. I think I had to look...
by Lou Jost
Thu Sep 03, 2020 5:48 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Large format macro tests
Replies: 35
Views: 581

Re: Large format macro tests

with enough resolution and sharpness that every die marker can be seen clearly Lou, your reply came in while I was writing my reply to Rik. Does the above help in understanding, or is the 100% IQ requirement still unclear? THis is the part you've been leaving out. Your main criterion is NOT just th...
by Lou Jost
Wed Sep 02, 2020 8:52 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Large format macro tests
Replies: 35
Views: 581

Re: Large format macro tests

There has to be something else in your criterion, Ray. You can always get 100% sharpness from an image if you downsample it enough. But that's losing information, and you agreed that is bad. You must have some additional constraint that you are following. Maybe "100% sharpness on a high-end consumer...
by Lou Jost
Wed Sep 02, 2020 6:57 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Large format macro tests
Replies: 35
Views: 581

Re: Large format macro tests

I think high resolution is an important quality in nature photography. I want people to forget that they are looking at an image; I want them to be able to run their eyes over the textures and details that are an essential part of an organism's beauty, as if they were examining the thing itself. In ...
by Lou Jost
Wed Sep 02, 2020 5:58 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Large format macro tests
Replies: 35
Views: 581

Re: Large format macro tests

I want to archive them digitally, though I also dream of someday making big exhibition prints. Exhibitions often have prints more than a meter wide, and allow a close approach to examine details. One of my friends made prints almost 2 meters high for an exhibition that I introduced in Amsterdam. The...
by Lou Jost
Wed Sep 02, 2020 5:01 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Large format macro tests
Replies: 35
Views: 581

Re: Large format macro tests

For sure I have tried pushing the envelope to capture as much image detail as possible, but with the same end goal...to get the best 100% pixel-level detail. I think you are leaving out something important about your goal. If that was really your goal, you would have stopped with a low-megapixel se...
by Lou Jost
Wed Sep 02, 2020 3:16 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Large format macro tests
Replies: 35
Views: 581

Re: Large format macro tests

We differ on what we mean by "image quality". I am discussing the quality of the aerial image that the sensor is trying to capture. For that, obviously, "sharp at 100% resolution" is not an adequate criterion, because you could easily ahieve that with any reasonable lens if you used a low-megapixel ...
by Lou Jost
Wed Sep 02, 2020 3:02 pm
Forum: Equipment Discussions
Topic: Another questionable eBay listing
Replies: 14
Views: 454

Re: Another questionable eBay listing

Yes I do remember that. I recall the price was good.
by Lou Jost
Wed Sep 02, 2020 12:56 pm
Forum: Equipment Discussions
Topic: Another questionable eBay listing
Replies: 14
Views: 454

Re: Another questionable eBay listing

I've bought something from Chendata, and it was in great condition. He also seems knowledgable. But there is something a little dishonest (perhaps not intentionally) about many of his listings. For example, he is currently selling a Linos 608 lens which he more or less claims is an industrial varian...
by Lou Jost
Wed Sep 02, 2020 12:08 pm
Forum: Equipment Discussions
Topic: Another questionable eBay listing
Replies: 14
Views: 454

Re: Another questionable eBay listing

Maybe I am mis-remembering. Scary dishonesty in any case.
by Lou Jost
Wed Sep 02, 2020 11:50 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Large format macro tests
Replies: 35
Views: 581

Re: Large format macro tests

It is not so easy to get a good looking 100% image, even if your camera is only 5MP. You're right. But as we've discussed before, the 100% criterion is artificial and makes no sense as a judge of image quality, though it may make sense in practice if your target is users who always zoom in to 100%....
by Lou Jost
Wed Sep 02, 2020 11:01 am
Forum: Equipment Discussions
Topic: Another questionable eBay listing
Replies: 14
Views: 454

Re: Another questionable eBay listing

I wondered about thatRayfact listing. When I saw it, there were six available.
by Lou Jost
Wed Sep 02, 2020 10:29 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Large format macro tests
Replies: 35
Views: 581

Re: Large format macro tests

Most everyone on the web zooms to 100%, which is why I place such a high premium on high IQ at 100% Yes I know, that's why I mentioned "web clients who automaticallly zoom in to 100%". But it should be obvious that this is not, by itself, a valid indicator of lens or image quality. Otherwise we'd a...
by Lou Jost
Wed Sep 02, 2020 9:13 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Large format macro tests
Replies: 35
Views: 581

Re: Large format macro tests

Lest this result seem too obvious, I think we all agree that for m large enough, these two images will be equally blurry, due to empty magnification. I'd like to see where that happens.
by Lou Jost
Wed Sep 02, 2020 9:05 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Large format macro tests
Replies: 35
Views: 581

Re: Large format macro tests

Yes, but that's real loss. Remember we're comparing same FOV on the two images, and that's what counts (unless you have web clients who automaticallly zoom in to 100% without thinking about what they are looking at). If both images were printed at the same size, this is what they would each look lik...