ProfHankD

ProfHankD

Lives in United States Lexington, United States
Works as a Professor
Has a website at http://aggregate.org/hankd/
Joined on Mar 27, 2008
About me:

Plan: to change the way people think about and use cameras by taking advantage of cameras as computing systems; engineering camera systems to provide new abilities and improved quality.

Comments

Total: 652, showing: 1 – 20
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On False Colors challenge (2 comments in total)

Remember: when voting, please favor entries that are fully compliant with the rules, which do specify that the color changes made should be described.

Direct link | Posted on May 21, 2015 at 02:14 UTC as 1st comment

Cute and clever commercial. However, the video is really annoying due to slow and sloppy focus hunting, and I was expecting in the end that they'd be saying how this was shot on a DSLR and then show how much better their product does. Instead, they brag it was shot on an E-M5 II. Ouch!

Direct link | Posted on May 21, 2015 at 00:46 UTC as 68th comment | 1 reply
In reply to:

KonstantinosK: "...they've garnered plenty of attention since then...". Really?

poppyjk: interesting again. So 3-6 weeks must == "in stock" to DPReview? Actually, it still says 1 left for the kit with lens, so I guess the body is technically in stock until that one is gone.

Direct link | Posted on May 19, 2015 at 17:55 UTC
In reply to:

KonstantinosK: "...they've garnered plenty of attention since then...". Really?

poppyjk: interesting. It wasn't out of stock at Amazon when I looked. You think DPReview's post here has something to do with that?

Actually, you're wrong. Look at the link near the top of this page -- it says "Support DPReview. Shop with amazon.com ... in stock."

Direct link | Posted on May 19, 2015 at 17:36 UTC
In reply to:

KonstantinosK: "...they've garnered plenty of attention since then...". Really?

Neither T6s/i makes DPReview's popular list. The T6s is ranked #42 in DSLR sales at Amazon, making it the 19th highest selling Canon DSLR right now.

In context, saying that's "plenty of attention" is a pretty strong insult to Canon. ;-)

Maybe somebody just confused Canon 750D with Nikon D750?

Direct link | Posted on May 19, 2015 at 14:22 UTC
On The Rock in the False Colors challenge (1 comment in total)

Very nice and creative effect!

Direct link | Posted on May 17, 2015 at 20:43 UTC as 1st comment
On Canon EOS 5DS R real world sample gallery posted article (356 comments in total)
In reply to:

ProfHankD: To me, the one obvious lesson here is that at 50MP FF, even 11mm @ f/5.6 has quite limited depth of field. I can't imagine anyone consistently nailing focus using manual focus with an OVF at 50MP. This will be a challenge even for focus peaking and magnified live view....

stevo23: Certainly you're right, but if I'm happy with 36MP or less, why would I ever move to a Canon sensor with poorer DR, etc.? BTW, I use all Sony E/FE bodies for high-end stuff; I only use Canons for reprogramming under CHDK or ML (I actually use more Canon PowerShots under CHDK than anything else).

Direct link | Posted on May 17, 2015 at 11:37 UTC
On Canon EOS 5DS R real world sample gallery posted article (356 comments in total)
In reply to:

ProfHankD: To me, the one obvious lesson here is that at 50MP FF, even 11mm @ f/5.6 has quite limited depth of field. I can't imagine anyone consistently nailing focus using manual focus with an OVF at 50MP. This will be a challenge even for focus peaking and magnified live view....

stevo23: 50MP FF implies a quite small circle of confusion with a relatively large field. The small CoC implies a smaller DoF than one would expect for FF, and for manual focus, the large FF field makes most focus aids less effective or more awkward. There is an 11mm f/5.6 shot of a car interior here that shows a DoF on the order of inches... that's even less than my Sigma at 8mm on 24MP APS-C, which also has surprisingly little DoF.

Direct link | Posted on May 17, 2015 at 04:10 UTC
On Canon EOS 5DS R real world sample gallery posted article (356 comments in total)
In reply to:

ProfHankD: To me, the one obvious lesson here is that at 50MP FF, even 11mm @ f/5.6 has quite limited depth of field. I can't imagine anyone consistently nailing focus using manual focus with an OVF at 50MP. This will be a challenge even for focus peaking and magnified live view....

The 11mm isn't a fisheye... and my most used lens of my 140+ lenses is a Sigma 8-16mm that I usually use manual focusing at 8mm on my NEX-7 (equiv. field of view of 12mm on FF). If pricing was a little better, I'd have been one of the first in line for Canon's new widest rectilinear... although I'd use it mostly on a Sony A7II. ;-)

Of course, the shallower effective DoF is an issue for all lenses, but mostly for manual focus. The autofocus success rate on the Canon 85mm f/1.2 is way less than 100% -- that problem will persist on 50MP FF. However, their PDAF sensor for 1.6X crop "APS-C" 20MP has pretty much the same accuracy constraint.

Direct link | Posted on May 16, 2015 at 13:52 UTC
On Canon EOS 5DS R real world sample gallery posted article (356 comments in total)

To me, the one obvious lesson here is that at 50MP FF, even 11mm @ f/5.6 has quite limited depth of field. I can't imagine anyone consistently nailing focus using manual focus with an OVF at 50MP. This will be a challenge even for focus peaking and magnified live view....

Direct link | Posted on May 16, 2015 at 10:39 UTC as 24th comment | 27 replies
On Sources of noise part two: Electronic Noise article (229 comments in total)
In reply to:

junk1: This article matches my recollection from my MSEE classes. I remember doing the math, but can't recall it from 20 years ago.

Noise in the sensor / front end is very bad since if you amplify the signal 100x in the next stage (or "downstream"), that incoming (into the amp) noise is also (of course!) amplified 100x. This is why you want a strong pre-amp signal from your audio system - so it does not need to be amplified as much later "downstream".

The reason CHDK and ML work is that it isn't just the sensor tech that has stayed remarkably constant in Canons for over a decade, but pretty much the entire camera architecture. It's not just the sensor that needs to change in major ways, which makes change a very slow and expensive process. For example, the byte order of raw image data matches old 16-bit hardware, and awkwardly doesn't match the order used by the ARM32 processors in Canon cameras, but this mismatch has persisted for more than a decade (presumably because some of that ancient hardware is still in the JPEG processing pipe).

One has to remember that the camera industry Canon grew up in is one in which product life cycles were measured in decades, with almost all improvements being incremental changes to individual subsystems. They've not yet adjusted to the fact that cameras now are primarily computing devices that need to be designed as tightly integrated systems in short development cycles.

Direct link | Posted on May 15, 2015 at 10:36 UTC
On False Colors challenge (2 comments in total)

A reminder: the rules say you should describe the color change(s) you made. I will not disqualify entries failing to describe the color changes, but strongly encourage voting to penalize them.

Direct link | Posted on May 15, 2015 at 09:36 UTC as 2nd comment

Double reflections were in 96/197 test images -- that's less than 49% that this algorithm has any hope of working on. Still cool that it almost sort-of works with such a computationally cheap algorithm, but would any press coverage have been given this if it wasn't associated with MIT? (Were any previous algorithms?) The article also credits someone at the Hebrew University of Jerusalem as co-developer of the algorithm, yet the article title here says the work comes from MIT. Well, this "news" did come from the "MIT News Office." ;-)

Direct link | Posted on May 14, 2015 at 11:03 UTC as 28th comment | 1 reply
On Sources of noise part two: Electronic Noise article (229 comments in total)

Nice overview. Two notes:

1. JPEG tone curves are not what they used to be. It used to be that you'd never see more than about 9EV dynamic range mapped into a JPEG, but now there are various "fancy" tone-mapping algorithms (e.g., shadow boosting like Sony's DRO) and S-log-type encodings. Put another way, anything you can do to a raw in postprocessing could theoretically be done in-camera, and an increasing variety is being done in camera, especially using CHDK (Canon Hack Development Kit) or ML (Magic Lantern), so camera JPEGs can reveal much more than is suggested here.

2. Electronic noise characteristics vary wildly across cameras, especially when you include webcams -- which are still a large fraction of all cameras out there, although not one of great interest to most DPReview readers. A typical $3 webcam has a very different electronic noise profile from your Nikon D810, not just more noise (e.g., webcams often suffer various types of strongly patterned noise).

Direct link | Posted on May 13, 2015 at 13:57 UTC as 61st comment
In reply to:

terp02andrew: I am definitely intrigued by the 8mm. The Panny f3.5 fisheye I have now isn't bad, but f1.8 is a significant improvement :p The larger aperture does result in the Oly being about twice the weight though.

Looking at the gallery images, the Oly fisheye does look really good: no flare issues (amazing for a 17-element lens!), sharp even wide open, very little CA, only a bit of left-side softness in some images.

Still, I'm somehow not thrilled with the feel of the sample images. I don't know if it's that I'm not used to the 4x3 aspect for fisheyes or if it's a slightly odd projection choice, but something seems a bit off...? Maybe I've gotten used to Samyang's unusual projection?

Direct link | Posted on May 12, 2015 at 13:29 UTC
In reply to:

terp02andrew: I am definitely intrigued by the 8mm. The Panny f3.5 fisheye I have now isn't bad, but f1.8 is a significant improvement :p The larger aperture does result in the Oly being about twice the weight though.

I think f/1.8 is the answer to "why not just get the Samyang?"
BTW, it isn't a particularly great answer. ;-)

Direct link | Posted on May 12, 2015 at 11:12 UTC
In reply to:

davetj_uk: You can get an App called Camscanner for free for android/ipad that will scan in pdf or jpg.. it does a brilliant job as well.. Camscanner straightens your pictures, and crops out any unwanted space.. I wouldn't lug that QromaScan thing around with me to copy photos and I cant believe anyone would want to pay for such a thing.. I could knock that up with a bit of strong cardboard and use tissue paper as a diffuser for a table lamp or natural light.. $35... You got to be kidding me!!

Holding the camera parallel and the LED lighting are the main benefits, but I wonder about the LEDs. It can be very difficult to get even lighting with point sources, and the inside of the box seems to have made bad color choices.

Direct link | Posted on May 6, 2015 at 11:30 UTC
On Big Zoom: Nikon Coolpix P900 real-world samples article (153 comments in total)
In reply to:

brn: Warning: not for pixel peepers.

At 1:1, even this ISO100 images look terrible.

True enough. However, they look consistently good scaled to 4MP (well, with somewhat nervous bokeh) and that's sort-of enough for most purposes. This is about getting the shot with no lens changes, not ultimate IQ.

Direct link | Posted on May 5, 2015 at 23:58 UTC
On A photo. challenge (10 comments in total)
In reply to:

Chris Page: Is this a late April fools?
Seriously...

Glad we can use PS to get rid of the red eye of the Fiji Fish caught on a Friday and taken with a Fish eye lens!

Well, it better be a joke... it just seems annoying. The rule:

"Size on shortest side must be no shorter than 196.4 megapixels."

ensures there cannot be any valid entries, because an image with that dimension would not be accepted by the DPReview image uploader.

I've been very frustrated by how little attention folks pay to the (very reasonable) rules in the challenges I've posted... perhaps this challenge host has been driven insane by such behaviors? ;-)

Direct link | Posted on May 5, 2015 at 11:22 UTC

Ok, this is silly, or sad, or innovatively artsy, depending on how you think about it. However, the photos at the WWW site show the cell phone in the vertical orientation with every photo in the horizontal orientation. Beyond that, you'd think there would at least be something like a remote trigger built-into the hand, but no such thing is mentioned.

In sum, the idea actually has potential as a joke, art, etc., but this isn't a well-thought-out thing.... I predict we'll see a cheap, more functional, copy from China on eBay within a few months. ;-)

Direct link | Posted on May 3, 2015 at 13:08 UTC as 81st comment | 1 reply
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