Kendall Helmstetter Gelner

Kendall Helmstetter Gelner

Lives in United States Denver, CO, United States
Works as a Photographic Product Developer
Has a website at http://InsideAperture.com
Joined on Dec 30, 2002
About me:

Working on Phototgraphy and Photographic software.

Proud member of the International SIgma Users Group

Comments

Total: 75, showing: 1 – 20
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On Sigma 50mm F1.4 DG HSM | Art Lab Test Review preview (557 comments in total)
In reply to:

stevo23: Flare and ghosting seem problematic with this one. Wonder if a hood helps much.

Oh yeah, the ghosting is just terrible:

https://www.flickr.com/photos/carlzeisslenses/10185182664/in/set-72157635236491881

Oh wait, that's the Zeiss Otus...

Direct link | Posted on Apr 18, 2014 at 15:53 UTC
On Sigma 50mm F1.4 DG HSM | Art Lab Test Review preview (557 comments in total)
In reply to:

simpleshot: Of all the reviews so far (Lenstip, Digital Picture, DXO, SLR gear, Popular Photography, Gizmodo, Fstoppers), there are very little comments about contrast.
SLR gear claims that the local contrast on the Sigma is better than the Otus. Pop Photo just says that the Sigma produces "consistently-contrasty images".
I wonder why this area is largely ignored by reviewers.

You can also see that even here if you load up the comparison between this lens and the Zeiss. You can see the difference in contrast even when the image is reduced in size.

Direct link | Posted on Apr 18, 2014 at 15:51 UTC
On Sigma 50mm F1.4 DG HSM | Art Lab Test Review preview (557 comments in total)
In reply to:

Abu Mahendra: If only it focuses competently, what we will have here is the finest 50mm autofocus lens ever made for the Canon EOS system.

@Boky, the beauty of the Sigma lens is that you can use the USB dock to adjust micro-focus just for that lens! So then you can have TWO properly focusing lenses on your Canon body. :-)

Direct link | Posted on Apr 18, 2014 at 15:48 UTC
On Sigma 50mm F1.4 DG HSM | Art Lab Test Review preview (557 comments in total)
In reply to:

DStudio: This is clearly a good lens. Its images are nicer and more interesting than from most Sigma lenses.

But it does have flaws. For example, some of the samples appropriately show busy backgrounds (and foregrounds) that are sometimes distracting, even if you're not looking for them (example here: http://g2.img-dpreview.com/5A6544ADCB5C4EB1A75BF3F0AEBE46B8.jpg)

The somewhat disappointing new Nikon 58/1.4 doesn't appear to suffer this malady. There are other 50ish lenses that don't either.

And the Zeiss OTUS does a good job of melding an analytically sharp lens with beautiful rendering, although I'd lean more toward beautiful (and less technical), given the choice. For example, as long as I'm going MF, I think I'd rather use some older Leica designs.

But in today's market technical quality is emphasized by many people, which has also yielded film like Kodak's Ektar 100 (which didn't appeal to me when I tried it). So while I might not choose it myself, the OTUS gives an amazing balance.

In that particular image, you have a lot of vertical lines. The Zeiss does exactly the same thing when encountering a busy background and sometimes just adds lines anyway:

http://www.the-digital-picture.com/Pictures/Picture.aspx?Picture=2014-02-09_15-05-22

https://www.flickr.com/photos/carlzeisslenses/11048471284/in/set-72157635236491881

And what is going on with the edge of this flower?

https://www.flickr.com/photos/carlzeisslenses/10185182664/in/set-72157635236491881

Direct link | Posted on Apr 18, 2014 at 15:47 UTC
On Sigma 50mm F1.4 DG HSM | Art Lab Test Review preview (557 comments in total)
In reply to:

aftab: In a recent interview Sigma president commented that they could have made this lens a little more sharper, but if they did then they would have sacrificed some local contrast, so this is the balance they went for. So, the trade off between resolution and contrast continues in designing lenses. It has been said that historically Leica favored contrast slightly over resolution and Zeiss did the opposite. Leica surely were able to create more ardent fans with their approach than Zeiss did. In an interview Leica's top engineer said that although now lens designing is much easier with computer input compared to before, subjective human input of their designers continues as before. While this kind of tests or MTF surely gives us a good insight as to how the pictures from a lens would look like, real life pictures definitely would give us a more complete picture. After all it is not all about sharpness, CA, vignetting or distortion. Hopefully, DPR would show us some real life comparison.

You can see that too in the comparison shots. If you load up the comparison between the Sigma and the Zeiss Otis, the graph says that they start out the same sharpness in the center and the Sigma decreases toward the edges. But if you look at the images themselves, the Sigma looks slightly clearer throughout because the contrast is better.

Direct link | Posted on Apr 18, 2014 at 15:39 UTC
On Sigma 50mm F1.4 DG HSM | Art Lab Test Review preview (557 comments in total)
In reply to:

CameraLabTester: Impressive low CA and distortion, but poor on vignetting. A good balance.

.

In what way "poor"? If you compare agains the Zeiss Otis it has slightly *less* vignetting! Some lens types simply have a bit of vignetting.

Direct link | Posted on Apr 18, 2014 at 15:37 UTC
On CP+ 2014: Hands-on with Sigma DP2 Quattro article (256 comments in total)
In reply to:

Frank_BR: Size-wise the Sigma dp2 Quattro is a giant. Indeed, it is wider than a Nikon D4! It is even wider than a medium format like the Leica S!

On the other hand, technically speaking the dp2 is a dwarf:
1. Maximum shutter speed: 1/2000s
2. Maximum ISO: 6400*
3. No video
4. No interchangeable lenses

(*) The low maximum ISO is a strong indication that the dp2 sensor is noisier than the traditional Bayer sensor.

It also has a flash sync of 1/2000, how many DSLR's with the same quality of output can say that?

Direct link | Posted on Feb 14, 2014 at 06:46 UTC
On CP+ 2014: Hands-on with Sigma DP2 Quattro article (256 comments in total)
In reply to:

TheDreamingWatchman: Cameras have only a small hump at the back, but a big one at the front.
And there's a good reason for that. The reason is our hand.

But this one has the big hump on the back.

"Cameras have only a small hump at the back, but a big one at the front And there's a good reason for that. "

Because companies like to follow the herd.

I don't recall many smartphones having that same characteristic, which is what most people use now for photos. If the Hump Design is the best one, why do smartphones and small compact cameras have no humps?

To me the Camera Hump is like the raised turbo scoop on the hood of a car lacking turbo...

Direct link | Posted on Feb 14, 2014 at 06:45 UTC
On CP+ 2014: Hands-on with Sigma DP2 Quattro article (256 comments in total)
In reply to:

carlos roncatti: Why the heck no photos with the guy holding the camera showing a position that he will take photos with it?

You can see a video of someone holding/using it here, it actually ends up looking fairly easy to hold:

http://m.youtube.com/watch?v=wOLfIJgSjRk

Direct link | Posted on Feb 14, 2014 at 06:36 UTC
In reply to:

yabokkie: I think I understand the design a bit more now.

they intentionally made the right thumb less efficient for camera setting by locking it for holding. this will have a designed effect to make one drop the camera in operation more easily. then the poor guy may buy another dp.

Why do you think the thumb is locked? With the shape it has it seems easy to hold with fingers alone curled in front, leaving your thumb to work the controls.

Nothing beats holding it and knowing though.

Direct link | Posted on Feb 13, 2014 at 04:01 UTC
In reply to:

Gesture: We can spin things any way we want, but 15 down to 4.9 is not progress. If the Foveon issues could be solved, you go 10:10:10 at a minimum. That huge body begs an integral EVF or swivel design.

It's not 15 down to 4.9. It's 15 gone up to 19. You need to read how the sensor works again. You are going to be astonished when you see the sample images.

Direct link | Posted on Feb 13, 2014 at 03:55 UTC
In reply to:

Trollshavethebestcandy: It would be interesting to have a sensor of two layers, quad blue on top and a semi random Fuji like array of red and green underneath. 20 megapixels in both layers. This would reduce the limitation of red issue being under only one layer instead of two. Any thoughts? Am I crazy?

Why would you have a random array of red or green when you can have them everywhere? That's what the Quattro sensor does, red and green sensors across the entire frame, just one above the other. Only they really are not exactly red/green, Sigma just labels them as "middle/bottom" because they capture more than just red/green.

Direct link | Posted on Feb 13, 2014 at 03:50 UTC
In reply to:

Jules Design: ok so I shoot product photography with a D800 and 105 mm prime
tethered, in-studio, I meter the light, gray card. Will this baby outperform my current camera???

The DP3Q probably will, if you can live with the somewhat shorter focal length. The Current DP-M cameras already out-resolve the D800 in some situations, especially when there is fine detail.

Direct link | Posted on Feb 13, 2014 at 03:48 UTC
In reply to:

Trollshavethebestcandy: I can see a third party horizontal grip attaching to the tripod mount with an additional tripod mount L bracket center to lens barrel. This cam seriously needs a wifi option for remote capture and a cable release socket.

You can always use an EyeFi card if you want WiFi support, why should Sigma spend extra developing that, and add more to the price of the camera when not everyone will want or need it?

Direct link | Posted on Feb 13, 2014 at 03:47 UTC
On Have your say: Best Fixed-lens Compact Camera of 2013 article (91 comments in total)
In reply to:

bluequartz: Another way of choosing them if size and budget aren't major concerns:
15 MP (effective) @ 75 mm? DP3
24 MP @ 35mm? RX1R
16 MP @ 35mm? X100s
16 MP @ 28 mm? GR or Coolpix A

They have similar image quality to begin with, and anyone looking at them are likely well-versed in post-processing to tune the camera's nuances/colours to their own liking.

They're further apart in terms of controls and operations, seeing how only X100s has a built-in EVF and the DP3 can be a slower (going by others' opinions), but pragmatically none of them are committing major usability no-nos. Still, I'll recommend testing cameras in person to see how they feel In (Your) Real Life.

Size and cost can be judged more objectively. If there's already a strong reason why only the GR is affordable, then stick to it or wait for price drops/new products.

Hence, I feel it boils down to how much resolution one wants at a given focal length (and range for cropping). That's the one thing that these cameras can't change.

The DP3 is 30MP (effective), not 15... is 15 million photo sites TIMES 3. The 16MP cameras you list, have 16 million photo sites total... It's pretty well understood at this point that a Foveon sensor has as much detail as a bayer sensor with about 2X the amount of photo sites in a single layer.

Furthermore, the DP-3M is super sharp across the whole image. None of those other cameras can make the same claim.

Direct link | Posted on Dec 19, 2013 at 07:50 UTC
On Have your say: Best Fixed-lens Compact Camera of 2013 article (91 comments in total)

The Sigma DP-3M is just amazing in terms of sharpness:

http://www.flickr.com/photos/kigiphoto/8731086248/sizes/o/in/set-72157633459763493/

Direct link | Posted on Dec 19, 2013 at 00:06 UTC as 36th comment
On Apple buys 3D sensor company PrimeSense post (4 comments in total)

Drawing clouds on your ceiling is the next Microsoft Surface (not the tablet).

However I have to say that proposing during a video game and having your Roomba bring you the ring might possibly be the least romantic proposal ever. Although virtual "big wall" would be an awesome date game.

Direct link | Posted on Nov 21, 2013 at 06:33 UTC as 1st comment

"As a 2X zoom lens, the Olloclip has some of the cleanest optics I’ve seen from an iPhone accessory."

If so, then you have not looked at the Schneider Optics iPro line of lenses - they too have a 2x converter, and also wide angle adaptors. I know from personal experience the WA adaptors are much nicer in quality than the Olloclip, so I would think the 2X adaptor would be also.

The thing is that with cameras of lower resolution you need to spend MORE effort to get distortion-free gear, because you have fewer pixels to recover data from. The Olloclip is already expensive so why not spend a bit more to get something even better?

Direct link | Posted on Nov 5, 2013 at 04:22 UTC as 3rd comment

I've always had my cameras in a coat pocket and take them out to shoot if I see something interesting - not once have I ever been asked to turn a camera off. That goes for both takeoff and landing.

It will be a boon for people using the iPhone for shots though, as anything that looks like a phone they would ask to be off.

Direct link | Posted on Nov 5, 2013 at 04:16 UTC as 7th comment

I have to admit, I am really impressed with Seene. It's not always perfect but the effect is pretty good even when it is not.

Hard to say if it will be only a fad or not, but anything that has a proprietary format usually is... on the website for people that can't see the 3D effect they should convert it into a looping movie that tilts up and down and right and left.

Direct link | Posted on Oct 20, 2013 at 20:56 UTC as 2nd comment
Total: 75, showing: 1 – 20
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