Joseph S Wisniewski

Joseph S Wisniewski

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

Canon S100, S400
Nikon D3, D2X, 2x D100 (all with Markins Arca plates)

AF primes (Nikon, unless otherwise noted)
300mm f2.8 AF-I
200mm f4 AF-D micro-Nikkor
135mm f2.0 AF DC
85mm f1.4 AF-D
60mm f2.8 AF micro-Nikkor
50mm f1.4 AF
2x 50mm f1.8 AF-D
50mm f1.8 AF
30mm f1.4 EX Sigma (out for service)
28mm f2.8 AF-D
20mm f2.8 AF-D
14mm f2.8 AF-D
14mm f3.5 AF Sigma (out for service)
8mm f4.0 AF Sigma

AF Zoom
70-200mm f2.8 AF-S VR
70-210mm f4-5.6 AF
24-70mm f2.8 AF-S
18-70mm f3.5-4.5 AF-S DX
17-55mm f2.8 f2.8 DX
14-24mm f2.8 AF-S
12-24mm f4.0 AF-S DX (sale pending)

MF
105mm f2.5 AI-S
105mm f4.0 El-Nikkor (great macro lens on a Nikon Bellows)
75mm f2.5 Voigtlander Color-Heliar (out on loan)
55mm f2.8 micro-Nikkor
55mm f3.5 micro-Nikkon
50mm f2.8 El-Nikkor
45mm f2.8 AI-P (the 'pancake' Nikkor)
40mm f2.0 Voigtlander Ultron Aspherical (that friends keep borrowing)
35mm f2.8 PC Nikkor (shift lens)
28mm f4.0 PC Nikkor (shift lens)

Comments

Total: 483, showing: 361 – 380
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On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

Suat Ateslier: What are the differences from my 60D ??

And, to give sharper shots with refractors, which aren't well corrected into the IR.

Direct link | Posted on Apr 4, 2012 at 13:58 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

Andy Crowe: No built-in astrotracer like Pentax DSLRs have?

The Pentax astrotracer capability isn't for this sort of photography. It can only track for a few minutes with "regular" lenses, and for a few seconds with a telescope.

Scopes are pretty much always used with motorized tracking mounts, so they can go for hours.

Direct link | Posted on Apr 4, 2012 at 13:55 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

treepop: wha!? Of all things...Don't most people mod their cameras on their own? I dunno.

You're quite welcome, Ben.

Direct link | Posted on Apr 4, 2012 at 13:50 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

johnparas11zenfoliodotcom: The question that comes to mind from an ignorant person about astrophotography.. Can one use this as a regular camera?

If the 60Da is anything like the 20Da, it already has two hot mirrors, and doesn't need another.

"Regular" cameras have two IR blocking filters, a hot mirror and a blue-green "Schott BG-34" style absorption filter. Canon replaced the blue-green filter in the 20D with a second hot mirror to make the 20Da. This boosts the h-Alpha sensitivity 3-4 times, but cuts IR even more than a "stock" camera, for sharper images with expensive refractor scopes (and to avoid the Sony "x-ray camera" debacle).

The filter you need for regular color photography is a "BG-34" type, like a B+W 489.

Oh, and sorry, kimvette, but it sounds like 60Da isn't going to work for "general" IR photography.

Direct link | Posted on Apr 4, 2012 at 13:49 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

IcyVeins: LOL what a ripoff. Canon is getting utterly destroyed with every new half-baked product they try to turn out. Just make another Rebel that's identical to the previous one already.

F&F, imagine how Icy would be praising the thing, if Sony had made it. ;)

Direct link | Posted on Apr 4, 2012 at 13:36 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

Xon_Fedaa: "“The EOS 60Da is a testament to the constant desire to meet the needs of every customer, including those in specialized fields,” said Yuichi Ishizuka, executive vice president and general manager, Imaging Technologies & Communications Group, Canon U.S.A."

Really, Mr. Ishizuka? Please point out to me Canon's offerings that have user removable IR filters to enable the sizable constituency of photography enthusiasts and artisans to take infrared photos.

Indeed, it would seem Canon's "desire to meet the needs of every customer, including those in specialized fields" isn't being fully realized.

Sigma SD1, here I come.

Regards,

Xon

"Please point out to me Canon's offerings that have user removable IR filters to enable the sizable constituency of photography enthusiasts and artisans to take infrared photos."

There won't ever be such a camera form Nikon, Canon, or Sony. Major camera companies remember the "Sony lesson". Sony used to have a camcorder feature called "nite shot" that slid the IR blocker out of the optic path. Some adventurous people discovered that, combined with a common Wratten 89b or 87 filter, you had a decent IR camera, and did typical IR art.

Some other folks discovered that, occasionally, this also let you see a woman's undies through certain clothing, and the legend of the "x-ray camera" was born. Next thing you know, angry mothers are burning or smashing piles of Sony equipment and demanding that the government "protect the children from pedophile photographers".

That's why Fuji only marketed their S5-UVIR through LEA equipment distributors, as a "forensics" camera.

Direct link | Posted on Apr 4, 2012 at 13:34 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

chn_andy: Actually if you do the modification yourself by just removing inner IR absorption glass (Color correction Filter) while preserving the Dust reduction filter, you will have at least 4~5 fold gain in sensitivity at H-Alpha. The ICF in 20Da has only 80% transmittance instead of 99% for an dedicated astrophotographical modification.

If you do what you suggest, and your telescope is not well corrected for IR, you'll get a soft red channel. Hot mirrors serve a purpose in astrophotography.

Oddly enough, it's typically the folks with the most expensive scopes who have the most trouble. The Takahashi refractors are not known for good IR correction, while any old Dobby is going to do just fine.

Direct link | Posted on Apr 4, 2012 at 13:27 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

Rakesh Nagar: Please someone let me know can this cam do Normal IR Black and White also
like we use to do with B&W IR with film if yes I will be the first Indian to buy.
THx

No, it's not likely to be able to do IR in any meaningful way.

Canon's press release sounds like 60Da works exactly like 20Da, which can't do IR photography. Most cameras have two IR blocking filters, a blue-green absorption filter and a dichroic "hot mirror" filter. 20Da replaced the blue-green one (which absorbs h-Alpha, and equalizes the camera's response to keep the red channel from blowing) with a second hot mirror.

So, 20Da did worse IR , less sensitivity and more ghosting, than a plain-old 20D. Poor results with a "false color" IR filter like Wratten 89b or R72, and pretty much dead to the B&W filters like Wratten 87 or RM90.

There's two reasons for that. One is political (the backlash from parents against IR capable Sonys) and the other scientific (refractor telescopes are not corrected for IR, and it makes color shots softer).

Direct link | Posted on Apr 4, 2012 at 13:15 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

mahonj: Why don't camera companies make the occasional monochrome camera - no bayer filter, no quarter wave plate, just very sensitive, very sharp images.

It would be very specialist and would sell in small-medium numbers, but if you can build an astro version, you should be able to build a mono version.

Apart from the different software/firmware, can anyone think of a reason ?

Canon sell so many 60Ds and 600Ds, they should be able to run a few mono versions.

@pntbll248, you probably don't want to bother with an SD-1 in monochrome mode, for three reasons.
* It has no liveview. The original 20Da had one of the first, rather rough and experimental, liveview systems, something they didn't put on the original 20D.
* It's monochrome. Look at the picture on the 60Da screen in the press release. Astrophotography is a colorful field.
* It's not as good as the Canon in very long exposures, and monochrome mode doesn't address that.

Direct link | Posted on Apr 3, 2012 at 14:45 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

oscarvdvelde: "hydrogen-alpha light sensitivity that is approximately three times higher than that of a normal Canon DSLR camera. This produces a 20-percent higher transmittance ..."

Confusing at first, but it seems to mean that the quantum efficiency at 656 nm is 10% in standard Canon cameras, and 30% in this camera.
That would make it more sensitive than 5D and 5D II, or a modified 40D, see these graphs: http://www.astrosurf.com/buil/50d/test.htm

I think you nailed it. I don't know the transmission of Canon's particular blue-green balancing filter, but the Schott BG-34 that is the grandfather of them all is just 8% transmission at 656nm. Pulling that got us a 3 stop boost for h-Alpha.

Direct link | Posted on Apr 3, 2012 at 14:36 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

treepop: wha!? Of all things...Don't most people mod their cameras on their own? I dunno.

A lot of people send them in to places like LifePixel or MadMax, but a lot of other people, especially purchasing people, like the simplicity of ordering what you want, and they like warranties.

Direct link | Posted on Apr 3, 2012 at 14:34 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

Sdaniella: Interesting... this is the second XXDa model since 20Da was first to offer ExpSim LV for optimal preview of DR of luminous cosmic bodies... and selection of exposure-ISO-sensitivity parameters 'live'
But now with VASS (Vari-Angle Swivel Screen of 60D and PowerShots)
I wonder if the EV range for ExpSim LV is extended to much longer exposures.
I wonder if the Da spec IR filter also improves Solar spectrum IR photography as well (video along with stills).
I hope the multiple exposure composite feature is allowed in JPEG mode, not just RAW mode.

No. It actually cuts more IR than a conventional filter. If you want to do near IR astronomy, your best choice is having the camera's IR blocking filter removed entirely. That's not a "politically correct" option for Canon to offer, but it's a superior solution for most astro needs.

Direct link | Posted on Apr 3, 2012 at 14:28 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

PeterZOOM: Nice to see some new Canon stuff, interesting, a camera for astrophotography with hotshoe and build-in flash ... okay then.

@gonzalu, it's "as a", not "asa". Muphry strikes!

More seriously, the "a" cameras have a better "hot mirror" (sharp cutoff IR blocker) than a regular camera. The filter you need for regular color photography is a "BG-34" type, like a B+W 489.

Direct link | Posted on Apr 3, 2012 at 14:25 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

micahmedia: Maxmax offers more flavors than this, if it's science ye be aftar.

High ISO astrophotography? Next they'll be suggesting flash astrophotography...

@bradleyg5, in astrophotography, EVERYBODY does have a motorized tripod.

Direct link | Posted on Apr 3, 2012 at 14:15 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

micahmedia: Maxmax offers more flavors than this, if it's science ye be aftar.

High ISO astrophotography? Next they'll be suggesting flash astrophotography...

@michamedia, you're talking about a field you don't understand, at all. Astrophotographers have been pushing the limits of ISO for over a century. They have various techniques for "hypering" film, such as soaking it in different chemical baths, "baking" it to achieve different silver grain geometries, and gassing it in tanks of pressurized hydrogen nitrogen mixtures. There's "preflashing", to tip more grains to near activation potential, then "latensification", to trip grains that were exposed "almost enough".

Where do you think the "back illuminated" sensors that are so popular now in small cameras came from? That's an astro technique, except they did it by hand, etching away sensors. There's also cooled sensors, with either big Peltier (solid state) coolers, refrigeration pumps, or liquid gas coolers.

Direct link | Posted on Apr 3, 2012 at 14:14 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

mahonj: Why don't camera companies make the occasional monochrome camera - no bayer filter, no quarter wave plate, just very sensitive, very sharp images.

It would be very specialist and would sell in small-medium numbers, but if you can build an astro version, you should be able to build a mono version.

Apart from the different software/firmware, can anyone think of a reason ?

Canon sell so many 60Ds and 600Ds, they should be able to run a few mono versions.

"if you can build an astro version, you should be able to build a mono version."

Actually, you can't, because the filters they change for the astro version are in front of the sensor, and the color filters are inside the sensor. Astro means making a change on the assembly line, put in this filter instead of that one. No extra QA, EMC, etc. testing. It can even be a repair-shop level modification. On the production line, you can make any quantity you want. 10, 100, 1000? Just give the assembly people the right number of filters.

The color filters are placed on the chip surface during IC fabrication. Changes to them require you to set up new fab steps, and make a new chip run. You have to get the quantity right, because the quantities are large (on a like like Canon's) and can't be changed quickly. Then you have to QA the new chips, and the cameras with the new chips, and do the EMC tests, because you've "changed" a chip.

That's why the monochrome Phase One cost an extra $12,000.

Direct link | Posted on Apr 3, 2012 at 14:08 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

mahonj: Why don't camera companies make the occasional monochrome camera - no bayer filter, no quarter wave plate, just very sensitive, very sharp images.

It would be very specialist and would sell in small-medium numbers, but if you can build an astro version, you should be able to build a mono version.

Apart from the different software/firmware, can anyone think of a reason ?

Canon sell so many 60Ds and 600Ds, they should be able to run a few mono versions.

@bradleyg5, actually, because the filter responses overlap, and because the green is the widest response of all and accounts for half the pixels, the filter loss for Bayer pattern cameras is under 50%. So, there's no "demolish" issue, and nothing "real" about your "real reason". Sorry.

"And obviously raw files wouldn't really work with any available software"

Actually, they do. Several Bayer demosaic algorithms, such as VNG (variable number of gradients) treat the image as "locally monochromatic" to begin with, and perform quite well when fed from a pure monochrome camera. Been there, done that. Raw Therapee has VNG as one of its available algorithms, and I believe Lightroom 4 does, just not by name.

And, of course, mImage has native monochrome support, but that's a subject for another day.

Direct link | Posted on Apr 3, 2012 at 13:58 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

MisoL: Besides astro-photography, this camera is suitable also for infrared photography and underwater photo/video, where red channel is very weak and correcting white ballance introduce lot of red noise. I'm using CSC camera with removed ir-cut filter for underwater and infrared photography.

Agree about the underwater shooting, but it's not at all suitable for IR work.

The Canon "a" filter pack lets more visible red (like H-alpha) through, but blocks IR. Several years ago, people discovered you could use Sony's "nite shot" camcorders as infrared cameras, and, under just the right conditions, this would enhance your ability to see a woman's undies through her clothes. Next thing you know, people have overblown this near useless ability into the "x-ray" camera scare. Crowds of angry mothers actually burnt and smashed Sony products in "protect our precious children from perverts with Sonys" rallies.

Direct link | Posted on Apr 3, 2012 at 13:51 UTC
On Canon launches EOS 60Da DSLR for astrophotography news story (227 comments in total)
In reply to:

Suat Ateslier: What are the differences from my 60D ??

I guess that means you, Thorbard. Canon "a" cameras, like 20Da actually block more infrared than conventional Canons. They omit the blue green (BG-34 type) filter, and add an second dichroic IR cut. This is done specifically to keep the camera from working as an IR camera, because of the negative press from the Sony "x-ray" camera incident.

Direct link | Posted on Apr 3, 2012 at 13:44 UTC

Not a good time to be PhaseOne.

The traditional medium format market has been shrinking for years, and that's before 645D took one bite out of it, and D800 just opened wide to take another.

And now Adobe comes along and sets new, lower price points for the entire raw converter / workflow manager industry.

Direct link | Posted on Mar 22, 2012 at 13:15 UTC as 5th comment | 2 replies
Total: 483, showing: 361 – 380
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