ah, nice, yes, synching is always a problem at high speed, it is fine for "long duration" exposures like stacking, it is another story for high speed photography. from the 1/4 power graph, the cut-off does look like what we see for 1/128th.

really nice work! I used to use a photo-diode with larger sensing area so I can get a nice curve, particularly the tail where flash tube "cools off" but still emitting light (or heat), forgot the model number, I also used it for lightning detection. But your graph seems a bit too symmetrical, usuall...

Oh, you can rotate it so you can shift vertically. Unfortunately, the camera grip is limiting amount of shift. When used with extension, I can shift left and right about 1 cm with that silver 50mm lens on Sony A7R5 full frame camera without any dark corners, I think I can do more, but due to the len...

I was playing with some lenses I got back in 2019, they are supposedly to be from some copier machine and they were "given" to me when I bought a Moritex lens from a seller on Taobao because the seller refuses to ship free. I think these are so called "red wine" lenses (in Chinese community) due to ...

last time a friend on Facebook passed away, I had to consult a friend (she is an American) on what to say about the situation as I am not good at emotional stuff, always detached from it, but this news feels somewhat very uncomfortable . . . wines should get me down, and sure the Excedrin for tomorr...

by the way, is the attached setup yours? if so, I assume the camera is a M4/3 camera, and I do not see an adapter from Nikon to M43, for that lens to form an image at infinity, the sensor needs to be 46.5mm away from the lens mount, to adapt that lens to M4/3 camera or your specific camera, you nee...

by the way, is the attached setup yours? if so, I assume the camera is a M4/3 camera, and I do not see an adapter from Nikon to M43, for that lens to form an image at infinity, the sensor needs to be 46.5mm away from the lens mount, to adapt that lens to M4/3 camera or your specific camera, you need...

... assume focal length is 60mm, adding 43mm extension should, "as predicted", give you 0.7x. Lets say G is 50mm ... I do not really follow you, but if you think it is important I can measure the "G" - "the gap between front of lens to subject" I guess this is the "working distance", but the predic...

furthermore, lets do this: assume focal length is 60mm, adding 43mm extension should, "as predicted", give you 0.7x. Lets say G is 50mm (probably less than that), under such assumptions so here are the calculations: u = 180 / (1.7) = 105.88mm, v = 180 - u = 74.12mm, yielding f = 43.6mm, very differe...

did some more experiments, when focused to infinity, ie, fully retracted, my Sony 50mm f/2.8 macro lens has about 51mm thin lens equivalent focal length actually, looking at the setup image on page 3, if the focal length is 60mm, the distance from sensor to subject should be about 240mm, but it real...

or maybe someone with an known focal length thick lens, and do an experiment to measure if the focal length is the same as the "infinity" defined. Also by "known" means measured, not from some reference because sometimes, those reference sites can have different meaning.

Darn it, my computer kept crashing. Anyways, maybe we are dealing with a thick lens instead of an ideal thin lens. This thing has haunted me for a long while and I did some quick experiment with my Sony 50mm f/2.8 lens. Since I do not know its EXACT focal length, so I do not have a reference and the...

I am just curious about your way of scaling up and down, etc, not sure what is the point doing that. And I do not understand how you can say "but no data was lost", yet, data are lost and are highly distorted. The choice of algorithm is a good point, that matters a lot! I was referring to our excha...

Sym P. le wrote: ↑

Fri Dec 22, 2023 7:41 am

Here's me trying to move the slider to zoom in on the stitching.

Try harder j/k

So what are you trying to say? I think I left the zoom slider at 1:1, ie, at that point, it is 100% crop, any more to the + side, you will see pixelization. Hope that is what you were trying to say.

Have you had a chance to make a comparison of a 10x-upscaled vs 20x? :) I do not see the point of doing that, sorry, you have to enlightening me. :D And I think I did it before anyways just for you :D Ah, I might have missed that though I couldn't find it when looking through the posts right now. B...