Joseph S Wisniewski

Lives in United States Detroit, MI, United States
Works as a Speech and sensor scientist
Has a website at http://www.swissarmyfork.com
Joined on Jul 12, 2002
About me:

I've been in love with photography for over 40 years.

My favorite form of photography is macro, and much of my gear is of my own design.

I've done professional photography on and off for over 20 years.
Taught 8 years at Midwest Photography Workshops.
Designed 3 scientific digital cameras and 6 lenses.

Author of mImage and (coming soon to the App Store and Google Play) ColorForEveryone.

Comments

Total: 680, showing: 21 – 40
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Oh good grief, not the "charge in seconds" inanity again.

“you could charge your mobile phone in a few seconds and you wouldn’t need to charge it again for over a week,”

My S7 has an 11.1 watt-hour battery that gets it through a day. To get through a week would, therefore, be 77.7W-h. That's 280kW-s.

How many seconds is "a few seconds"? Let's be generous and say 60. You charge the phone at 4.7kW to hit 60 seconds. A bit much for a single domestic circuit, even in 220V countries. Let's make it 1kW, to make sure we can charge the phone on a single domestic circuit in a 110v country, with some lighting or a computer or TV sharing the circuit. That's 280 seconds, not really "a few", but about 5 minutes. We can live with that.

How much does a 1kW charger weigh? About 5 pounds and it's around 6in square, 4 in tall. Costs about $500. And you sure can't run 1kW through a USB-C connector.

Which brings us back to a practical charger, 5-20W, affordable, packable. In short, status quo.

Link | Posted on Nov 24, 2016 at 03:48 UTC as 35th comment | 3 replies
In reply to:

JOrmsby: I wish more of the lens companies would offer a fast macro in the 90-105mm (equivalent) range. Other than this new Voit, there's nothing except for the Zeiss Milvus 100 f/2. No autofocus versions. Having a lens in that focal length that can double as fast portrait (faster than 2.8) and macro would be incredibly versatile.

You're quite welcome.

Link | Posted on Oct 13, 2016 at 03:09 UTC
In reply to:

Richard Murdey: Practical consideration:

The original SL had the rabbit ears, but were true AiS lenses. This new Nokton has the chip+contacts, so unless they've done something very clever it conforms to the Ai-P specification: it behaves as an AF or AFD lens but without autofocus.

What that means is that on all modern Nikon dSLRs the camera will insist you turn the aperture to the max position and control the aperture from the body. That's right: that gorgeous scalloped aperture ring? You can't use it... unless you somehow remove or defeat the chip.

It's a bit of an irritant on all the Zeiss ZF2 and CV SLII and SLIIN lenses vs the older ZF and SL versions. I prefer the old versions for that reason: I like to turn the aperture ring!!

The aperture ring may be "gorgeous", but it's an ergonomic disaster.

https://www.dpreview.com/forums/post/38352079

It's also one more large ring to seal, and one more point of failure.

Link | Posted on Oct 13, 2016 at 03:07 UTC
In reply to:

JOrmsby: I wish more of the lens companies would offer a fast macro in the 90-105mm (equivalent) range. Other than this new Voit, there's nothing except for the Zeiss Milvus 100 f/2. No autofocus versions. Having a lens in that focal length that can double as fast portrait (faster than 2.8) and macro would be incredibly versatile.

You have both an APS Nikon and a MFT Oly.

How about a 60mm f2.0 Tamron? Autofocus and everything. Although a 58mm f1.4 Voigtlander is a lot of portrait fun on either of those bodies.

Link | Posted on Oct 6, 2016 at 01:09 UTC

Wow. "Voigtlander" has discontinued a huge swath of their line in multiple mounts. I'm betting it's pressure from "Zeiss" to launch more lenses with less competition.

Not that I don't love both my Cosina Zeiss 100mm f2.0 and my Cosina Voigtlander 40mm f2.0 and 58mm f1.4. ;)

Link | Posted on Oct 6, 2016 at 00:58 UTC as 18th comment | 1 reply
In reply to:

entoman: The Heliar and the Nokton would look pretty weird on a modern camera like a Sony!

The Macro however could be very useful - F2, a nice 10 blade iris for great bokeh, and compatibility with focus assistance features like peaking and magnification make it an interesting prospect for crop-sensor Sony machines.

However I often get the feeling that some lenses are designed by technicians who have little understanding of what photographers actually want or need. The focal length is just about usable for macro on a crop sensor, but 90mm would have been a far better choice, allowing a more sensible working distance that a) would not scare live subjects and b) would not interfere with lighting (or involve getting so close that the camera/photographer cast a shadow over the subject).

Oh, and the Nokton doesn't look "pretty weird" on either a Sony A7 or an a5100. Been there, done that. It looks awesome.

Link | Posted on Oct 6, 2016 at 00:51 UTC
In reply to:

entoman: The Heliar and the Nokton would look pretty weird on a modern camera like a Sony!

The Macro however could be very useful - F2, a nice 10 blade iris for great bokeh, and compatibility with focus assistance features like peaking and magnification make it an interesting prospect for crop-sensor Sony machines.

However I often get the feeling that some lenses are designed by technicians who have little understanding of what photographers actually want or need. The focal length is just about usable for macro on a crop sensor, but 90mm would have been a far better choice, allowing a more sensible working distance that a) would not scare live subjects and b) would not interfere with lighting (or involve getting so close that the camera/photographer cast a shadow over the subject).

Aside from all the good points that Karroly raised, flower and jewelry shots almost always benefit from the perspective of the longer macro lenses, and the extra distance allows for better lighting setups.

Link | Posted on Oct 6, 2016 at 00:47 UTC
In reply to:

Matsu: They need a large format digital back. LOL

If the film isn't pulled at a perfectly even rate, there are streaks on the print. It was hard enough learning to pull 4x5 (hint, hold the film steady, pull the camera away from the film). No way you can pull something with 25x the area.

Link | Posted on Jun 29, 2016 at 02:12 UTC
In reply to:

Matsu: They need a large format digital back. LOL

Actually, it has a motor drive. Granted, it's like one frame every 30 seconds, and needs to be plugged into a 110v outlet.

The 24x20 Polaroid uses two rolls of film that are driven through crushing rollers with a chemical "capsule". It's a bit big to pull by hand the way we did a 4x5.

Link | Posted on Jun 27, 2016 at 00:09 UTC
In reply to:

Bas Emmen: Techtalk blabla... Anyone noticed Rachelle di Stasio?

Actually, three people before you commented on her.

Link | Posted on Jun 27, 2016 at 00:04 UTC
In reply to:

Elliot H: the images that machine produced are nothing less than astounding

And the flashes. You're talking an emulsion that was ISO 75 when made (and is probably much lower aged 8 years) and a 1200mm f22 lens, which probably gets stopped down into the f64-f250 range.

Link | Posted on Jun 26, 2016 at 04:15 UTC
In reply to:

fmian: I'm sure the camera could still find a use with home made emulsions.

Have you got the formula for a color emulsion with a speed higher than ISO 3?

Link | Posted on Jun 26, 2016 at 04:12 UTC
In reply to:

Tilted Plane: From what I've gathered elsewhere, John Reuter's business used old stock 20x24 Polaroid film that he bought up in the final days. He never made his own or had anyone make it (which would have probably been Fuji if it had the incentive). So the multi-millions needed to produce the film would mean a whole new start-up, and yes, it's not going to happen. I'll add (having helped organize a Reuter workshop at a photography center years ago), the whole process of sitting, shooting, and then seeing the physical results is something unique (and fabulous) in the history of photography, and it will be missed. You might come up with a digital semblance of it, but then they wouldn't be one-of-a-kind (necessarily) and they'd lack some primal alive-ness that these 20x24 prints have.

You are exactly correct. They are sitting on some stock of film produced by Polarioid eight years ago, and their testing says another two years and it's going to hit the point where it can't produce professional looking results any more.

Link | Posted on Jun 26, 2016 at 04:04 UTC

You want to "essentially kill off the green screen"?

Use a time-of-flight depth camera like a Kinect 2.

Link | Posted on Apr 24, 2016 at 03:00 UTC as 6th comment
In reply to:

matthiasbasler: To the calculations and assumptions done by dpreview. I agree that this video beast likely has (an needs to have) an excess of resolution in order to give the editor a real choice for focus.

WIth the Lytro Illum you could refocus your image to any point, but there was only a limited range in which the image was anything like sharp. (It had two maxima at depth -4 and +4 with a local minimum at ±0 where the image was just acceptable, but not really good. This left me with no real choice where to put my subjects if I wanted them to be sharp (~-6 to -2 and/or 2 to +6, roughly).
Excess resolution would give me the freedom to re-focus on anything from, lets say, -10 to +10 and still have an acceptable sharpness.

P.S. They Lytro Illum did not have a spatial resolution of 5MP! The spatial resolution is nowhere officially stated (afaik) and the camera can only export rather soft 4MP JPG files, the effective resolution is ~2MP in ideal conditions.

In other words, it will give you enough wiggle room to "clean up" after a focus puller's minor errors. But it can't really refocus anywhere in the scene, simulate rack focusing, etc.

Link | Posted on Apr 24, 2016 at 02:57 UTC
In reply to:

Joseph S Wisniewski: "The multiple perspectives captured mean you can generate 3D images or video from every shot at any desired parallax disparity"

Except that single point cameras are essentially useless for 3D video, because the occlusion is only correct from the single viewpoint. Moving the viewpoint means that you now need background that was blocked from the single viewpoint.

The end result is that the images look like bad automatic 3D conversions, until a skilled artist retouches all occluded areas.

The human interpupillary distance ranges from about 50-70mm, and 3D filmmakers tend to shoot a bit wider. The "correct perspective shift within a limited area" of a lightfield camera is limited by the aperture of the lens. To get a minimal 50mm interpupillary distance on a normal lens would require a 30mm f0.5 on a super-35mm sized sensor.

I stand by my observation that "single point cameras are essentially useless for 3D video" and for 3D work, the lightfield cameras are essentially single points.

Single point techniques only work in macro 3D focus stacking, where the interpupillary distances are on the order of 1mm, not 60mm, and the background is totally out of focus.

Link | Posted on Apr 24, 2016 at 02:51 UTC

"The multiple perspectives captured mean you can generate 3D images or video from every shot at any desired parallax disparity"

Except that single point cameras are essentially useless for 3D video, because the occlusion is only correct from the single viewpoint. Moving the viewpoint means that you now need background that was blocked from the single viewpoint.

The end result is that the images look like bad automatic 3D conversions, until a skilled artist retouches all occluded areas.

Link | Posted on Apr 22, 2016 at 03:55 UTC as 11th comment | 6 replies
On article Hands on with the Hasselblad H6D 50c/100c (268 comments in total)
In reply to:

sean lee: Wow... 100MP.... Unbelievable...
But with that price, I can buy BMW or Audi...
I thought Leica was the most expensive camera...
Wow...

You are mistaken. They got the idea from the same place Blad got it from, Creo Leaf.

Link | Posted on Apr 18, 2016 at 23:31 UTC
On article Hands on with the Hasselblad H6D 50c/100c (268 comments in total)
In reply to:

sean lee: Wow... 100MP.... Unbelievable...
But with that price, I can buy BMW or Audi...
I thought Leica was the most expensive camera...
Wow...

Leica is the most expensive camera. Hasselblad has nothing in platinum, or with diamonds or ostrich skin.

Link | Posted on Apr 17, 2016 at 06:02 UTC
In reply to:

Funkyd3121: Who in the hack can afford this??

At my peak as a product photographer, no problem.

A lot of high end product, architecture, glamour, wedding, and portrait photographers can afford things like that.

Link | Posted on Apr 8, 2016 at 01:46 UTC
Total: 680, showing: 21 – 40
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