Swagon

Swagon

Joined on Apr 3, 2012

Comments

Total: 12, showing: 1 – 12

I'm an electrical engineer that works specifically on battery chargers for cell phones. I see stories like this fairly often. Some healthy skepticism is in order. Let's say the cellphone has a modest 2amp-hour battery. To charge in 30 seconds, which is 1/120th of an hour, would take a nominal 240amps. If the battery is the typical 4v or so, then it is nearly 1000 watts (vs a typical notebook charger at 65watts). This is like a microwave oven or a small hair blow dryer. The charger would need to be large and probably have a fan. The connectors need to be much larger. Note that a micro USB connector is rated for about 2amps. All these things are hidden from you in the video link, but you can see the fat cable. I can tell you that 30second charging is just not going to happen in a smartphone.

Direct link | Posted on Apr 12, 2014 at 18:16 UTC as 7th comment | 2 replies
In reply to:

caravan: The best zoom lens is a sharp prime and a good pair of legs.

I use my legs to get the perspective I want. Then I zoom to get the framing I want.
With a single prime, I would have to walk to get the framing and give up on getting the desired perspective. It I could carry a bunch of primes and switch lens every other shot on average.
A sharp and fast zoom is a fantastic tool.

Direct link | Posted on Sep 9, 2013 at 08:19 UTC
In reply to:

white shadow: Quality wise, this zoom should be quite similar to any consumer DSLR zoom of this focal length out there.

My only concern is the size of this lens which is not much smaller than that of a DSLR zoom. Looking at it, if one were to attach this to the X-M1, for example, it would not balance well thus affecting handling. This size of it will best be attached to a DSLR size body.

In such a situation, the micro 4/3 zooms are made to better size. Even the Lumix 100-300mm f/4-5.6 is only slightly bigger but it covers up to 600mm equivalent. The Lumix 45-175mm f/4-5.6 is quite small for its focal length.

If one is going mirrorless, the combo must be small otherwise we might as well use a DSLR.

Eventually, the flipply mirror will be viewed as a negative. Mirrorless will soon encompass full frame, and eventually larger sensors. Size is not the only reason to go to mirrorless.
I plan to buy the xe1 because it is big enough to fit my hand and it has very good APSC sensor, and a high quality EVF built in. Smaller cameras like OMD don't fit my hand well. I will buy the 55-200mm. Already played with it at the store and it is comfortable on xe1.

Direct link | Posted on Sep 8, 2013 at 22:42 UTC
On Soak in the season with these vivid summer photos article (38 comments in total)

While I usually drink Petite Sirah, this was a very enjoyable Caipirinha for a hot summer's day!

Direct link | Posted on Aug 26, 2013 at 09:20 UTC as 12th comment
On Soak in the season with these vivid summer photos article (38 comments in total)

Photography is art, and includes freedom of expression. There are no "rules". A good image is the one you like.
Who cares how these were made. Some people like them, and some don't, just like music or wine.

Direct link | Posted on Aug 26, 2013 at 09:08 UTC as 13th comment
In reply to:

Kiril Karaatanasov: if this indeed is f/55 lens it is beyond pointless and even surpasses ridiculous.

1. What is happening to diffraction?

2. How will anyone shoot this? iso 3200 in bright daylight?

3. At least a single sample would have been nice to put along if this thing is ready to hit stores so soon.

Relax. It will be fine in bright sunlight. As stated earlier by someone, this is f8 at wide and f25 fully zoomed. It won't be great because it is slow (f8+) and too cheap for really good correction, but it will be fine enough to please many amateurs who just want to get a reasonable bird photo. A tripod will be useful, or maybe mandatory.
I do serious astrophotography, and astro intended scopes have to be much better. Stars, outside of the sun, are point sources at any magnification no matter how huge your scope is. Point sources reveal spherical aberration, chromatic aberration, astigmatism, and many other optical flaws. I agree with other posters that most astro scopes will outperform this, but you would lose the zoom feature.

Direct link | Posted on Mar 29, 2013 at 06:35 UTC
On CP+ 2013: Interview with Olympus' Toshi Terada article (242 comments in total)

Richard, I do see your point, but I'm not yet ready to sell my 4/3rds DSLR stuff and buy micro 4/3rds. There will come a day when the EVF is superior to the optical finder. It already has many advantages, but I wouldn't call it superior just yet, especially if shooting action.

Direct link | Posted on Feb 2, 2013 at 10:12 UTC as 52nd comment | 5 replies
On CP+ 2013: Interview with Olympus' Toshi Terada article (242 comments in total)
In reply to:

88SAL: I wonder if the 4/3 sensor could be introduced into compacts. its cetaintly not APS-C sized but with that being said look at the large sensor SonyRX100 - it is reatively compact while offering great performance. Im sure readers could agree that a 4/3 sensor with some compact optics, a 12-50 f2 (remember 2x crop) lens or something similar might offer a compelling compact product, especially if its under $400USD. We dont need a compact zoom camera that is a brick like the RX1 or X100 by Fuji for an occasional use performance compact. (dont get me wrong, lovely cameras, awesome cameras - but think smaller).

I have the Oly 12-60mm f/2.8 for my 4/3rds E620. That lens is pretty big -- certainly not compact. Going to micro 4/3rds and cutting down the maximum zoom to 50mm might help shrink it a little, but asking for f/2.0 brings the size right back up.

BTW, I hope to stick with Oly DSLRs. I love the color and exposure. Every time I see Canon and Nikon photos unmanipulated from the camera, I am so glad we have Olympus. I know this is a controversial opinion, but it has to do with my preferences. Oly, please don't change your recipe any more than you already did. I am referring to my judgement that the older E420 had just slightly nicer colors and exposures than the E620. I still have the E420, and can't bring myself to sell it for this reason.

Direct link | Posted on Feb 2, 2013 at 09:56 UTC
On CP+ 2013: Interview with Olympus' Toshi Terada article (242 comments in total)
In reply to:

Carlos Echenique: No, the headline is correct for words ending in "s". Single apostrophe after the "s" to denote possession. I have experienced this for my entire life as my first name ends in "s". "Olympus's" is redundant.

I was taught to use trailing apostrophe only for plural possessive, such as "Birds' beaks come in many shapes." However, singular possessive always gets 's, even when ending in s. My church constantly gets this wrong with Jesus's name (which is the correct way). These rules were absolutely drilled into my head as a high school sophomore by the best grammar teacher I ever had. Thank you, Mr. Shibley. I'm nearly 50 now, but remember most of what he taught me; he was that good.

Direct link | Posted on Feb 2, 2013 at 09:35 UTC
On Canon launches EOS 60Da DSLR for astrophotography article (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

It will work much better than most cameras if you are using an R72 IR pass filter. I use an R72 on my unmodified DSLR. My optical finder is basically black, but live view works and I can still use it handheld outdoors with the image stabilization. The 60Da camera would probably work much better and need shorter exposures. But it still has a modified IR block filter, so it will not be better than an SLR modified in the aftermarket that has no IR blocking at all.

Direct link | Posted on Apr 4, 2012 at 00:25 UTC
On Canon launches EOS 60Da DSLR for astrophotography article (227 comments in total)
In reply to:

DaveMarx: Why does a camera strapped to a telescope, that's being pitched on the benefits of the camera's LCD display for viewing (hard to use an OVF when the mirror's locked up)... why does it need a mirror, OVF, and focal plane shutter (besides dust control)?

It's not sensor size any more. If I was Sony, and I was interested in making a splash in the scientific community, why not in astrophotography, with all its passionate amateurs? Save those budget-strapped folks a small bundle by ditching unnecessary mechanical systems, and it reduces weight-related stress on the telescope to boot. AND, it'll still do fine as a general-purpose camera.

Sure, for someone who owns a pile of Canon glass, and is using that camera for a whole lot more than astrophotography... it's another set of tools on the Swiss Army Knife. But this would have been a really cool way for Canon to introduce its mirrorless camera. It's not like they don't know how to make 'em. They're called pro video cameras.

True, a flip mirror has limited value in astroimaging. The live-veiw with 7x or 10x zoom-in window is a blessing for focusing. Without that, it would usually take me 30min just to focus. With liveview and 10x, I'm focused in just a couple minutes. Modifying the IR blocking filter to prevent it attenuating at visible deep red of H-alpha is a very significant improvement for astroimaging. A shutter is important because we want to easily take dark-frames without covering the front of the telescope. I usually take 8 to 32 dark frames and average them to remove all the random noise. That becomes my master dark frame, and it has to be redone periodically. Ideally, an astrocamera should also have a peltier cooler behind the sensor to lower the noise during long exposures. This is a huge benefit. And it should have a regulation loop to keep the sensor temp very stable so that the darks are the "right" dark frames. And it should provide 48-bit RAW files and USB remote control.

Direct link | Posted on Apr 4, 2012 at 00:19 UTC
On Canon launches EOS 60Da DSLR for astrophotography article (227 comments in total)
In reply to:

Joshlovesphotos: And.....here we go again DPReview. You basically copy and pasted the advertising from Canon's press release onto your "Review" site. Only problem is, when you "review" something, isn't the point of the site to take another, more objective view of a product? You should call yourselves, DPAdvertisers.

Problem? Well, besides apparently being the only person here with an iq over 100, how about the fact that hydrogen-alpha light is NOT the true color of the cosmos. You know those galaxy and nebulae that you see on science shows in awe striking color? Yeah. Thats false color. That's not TRUE color, I don't care how subjective it is. The human eye does not see colors that way. This article's main title should read "CANON ANNOUNCES MODIFIED 60D (60DA) WITH STRONGER INFRARED SENSOR THAT PRODUCES FALSE COLOR IN ORDER TO MORE EASILY PHOTOGRAPH THE COSMOS".

So basically you just pasted NEWS and FALSE ADVERTISING onto your "review" site, that is just chock full of adverts really.

The Canon Press Release is posted in the News section. Press releases are news; that's why they are called press releases. The DP reveiw section has reviews that are very thorough. This camera has not yet been "reviewed". When or if it gets reviewed, it will be a full-fledged review like their other reviews. I think there is a fair chance, however, that they will not review this particular model because I don't think they are qualified "astrophotograpers".
I am an astrophotographer, and H-alpha is definitely not false color. It is a deep red that is visible. Unfortunately, most digital cameras have IR blocking filters that cut off too early and severly attenuate the visible Ha wavelength. True, many astrophotos do use false color to map INVISIBLE wavelegths into other colors that are visible, or we couldn't see the image. These have both scientific value and aesthetic value. But most astrophotos are true-color and keep H-alpha as red and sun-like stars as white.

Direct link | Posted on Apr 3, 2012 at 23:52 UTC
Total: 12, showing: 1 – 12