Erik Magnuson

Lives in United States Cape Canaveral, FL, United States
Has a website at http://www.pbase.com/maderik
Joined on Dec 29, 2000
About me:

This is what I'd like to appear on my public 'posters (sic)
profile.'

Comments

Total: 264, showing: 1 – 20
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Visual tracking and adjusting to minor changes in motion is more important with tighter framing (i.e. longer lenses). Shooting field sports with a 70-200mm zoom is certainly less challenging than say tracking a jet flyby at an airshow or bird in flight with tight framing. But until there are longer telephotos with fast focus in E-mount, perhaps it does not matter much.

Link | Posted on Apr 14, 2016 at 12:49 UTC as 9th comment | 2 replies
In reply to:

Kamox: Want a cheap and good achromatic doublet (like this lomo)?
Use a close-up lens or a screw-on "wide converter" and mount them on a clear bayonet. Use extension tubes accordingly.
Example:
http://www.dpreview.com/forums/thread/3681396

Or look for the old T-mount Sima 100mm f/2 lenses. You can even use the same trick with Waterhouse stops and custom aperture plates.

Link | Posted on Apr 9, 2016 at 13:49 UTC
On article Hands-on with the Sony RX10 III (307 comments in total)
In reply to:

LF Photography: Although it seems like a powerful compact, it's high price and size place it in DSLR/Mirorless territory. Call me crazy, but I'd rather get a FF DSLR such as the K-1 for the ultimate in stills IQ and ruggedness. Video specs are nice, though.

Sony doesn't make a 600mm F/4 either. (It's a 220mm F/4)

Link | Posted on Mar 30, 2016 at 16:10 UTC
In reply to:

Aroart: Love some advice... Tony Northrop from SDP has made it very clear that putting a full frame lens on apsc body will not give the best image quality... That even using a kit lens made for the apsc will give better I.Q. If thats true is there a better lens than this for my 7dm2 with this type of reach... Love some feed back...

Tony's statement might apply comparing new kit lenses vs. older FF lenses. So in the context of telephoto zooms, yes the EF-S-55-250 STM is better than all of the old Canon 75-300mm FF lenses. The 55-250 might even be close enough to the 100-400L in the 100-200mm range. But if you need a 400mm lens, there is no APS-C only lens because optically there is little or no advantage to covering only APS-C in a super-tele. There is a better lens for your 7DII, but it's the $11k FF Canon 200-400mm L ;-)

Link | Posted on Mar 2, 2016 at 11:36 UTC
On article CP+ 2016: Hands-on with new Sigma SD cameras and lenses (305 comments in total)
In reply to:

Guenter Hofstaedter: would like to get one with nikon mount !

It would be very tough to make an Nikon to SA adapter (that keeps infinity focus) without exotic materials. The throat diameters are too similar to have enough metal for a strong mating. The one adapter made for the SD9/10 used the outer bayonet lugs that were dropped starting with the SD14.

Link | Posted on Feb 26, 2016 at 13:03 UTC
In reply to:

Potemkin_Photo: I'm also perplexed why no pure mirrorless mount. Not everyone wants sigma lesnes only

Then the chinese can make some for Sigma cameras. (The first inexpensive M42-SA adapters were made in Poland.)

Link | Posted on Feb 23, 2016 at 22:26 UTC
In reply to:

joe_leads: I'm wondering why they keep a DSLR mount for this camera. Why not make a new mirrorless mount with short flange distance and offer their existing DN lenses for Sony E, as well as future mirrorless lenses for both mounts? Their DSRL lenses could still be adapted.

Adapters are not suitable for lens testing. Or maybe if the focus path is not the sensor path and you can't do fine tune. In the real world they are no different than tele-converters.

Link | Posted on Feb 23, 2016 at 22:16 UTC
In reply to:

Potemkin_Photo: I'm also perplexed why no pure mirrorless mount. Not everyone wants sigma lesnes only

Canon only offers an adapter for other *Canon* lenses on the M. (Long ago, Canon offered Exacta and M42 adapters before they had a full line of FL/FD lenses. Essentially no camera maker supports other brand lenses if they do not have to.)

Link | Posted on Feb 23, 2016 at 22:12 UTC
In reply to:

itaibachar: If I could mount my Canon lenses on this thing, I'd buy it.

It's not about lens protocol communications - it's about a color correction profile that will vary depending on distance, aperture, and focus. Think of it like DLO for Canon DPP only required, not optional. This has to be maintained in SPP and camera firmware everytime Canon produces a new lens.

Link | Posted on Feb 23, 2016 at 22:00 UTC
In reply to:

kty: Come on Sigma, join the Micro 4/3 system and make these cameras with active MFT mount. They would be a totally unique offering to tons of people and undoubtedly very good sellers.

Sigma has a whopping total four m4/3 lenses and two of them are 30mm. Not much point with so little m4/3 support.

Link | Posted on Feb 23, 2016 at 21:33 UTC
In reply to:

itaibachar: If I could mount my Canon lenses on this thing, I'd buy it.

I suspect the problem is the required lens corrections. Look at the issues found using non-Sigma lenses on the SD1 and then remember all of the problems Kodak had supporting Nikon and Canon lenses on the 14n/14c.

Link | Posted on Feb 23, 2016 at 21:29 UTC
In reply to:

AkashRana: I never quiet understood Sigma SA-mount cameras, and their foveon sensors; which are presumed to be so great but i see no adopters for those sensors. Still bayer rocks the world

Sigma claims they will sell them to anyone who wants them. In the early days they were available in industrial grades for other purposes.

Link | Posted on Feb 23, 2016 at 21:26 UTC
In reply to:

jonny1976: what's the point of making it mirrorless?
is as big as a k1...near any dslr...it doesn't mount any other lens...like a pentax k01 it has the same distance of the dslr...sp it only mount the art gigantic lenses..great sensor but why simply not sticking with a conventional sd1x series? improving what didn't worked, buffer and high iso....i didn't understood it has this size , but after watching camera size.com...i really think sigma made many wrong choices....if they price like the past...who will buy this camera? even considering a sd1 can be bought in stock for 800 900 euro?

Compared to the SD1? More precise AF, better MF. Most Sigma shooters end up using their camera like classic static field cameras and would rather have precise AF/MF than an OVF and microadjust.

Link | Posted on Feb 23, 2016 at 21:20 UTC
In reply to:

Jekabs: This only makes sense for E-mount if:
- is very reliable with Sigma lenses and does not occasionally require a power cycle or re-mount of the lens or adapter;
- allows advanced tracking modes like Eye-AF, which are not available on adapters which emulate LA-EA1/3.

There is no repeat of the 35mm on the link I provided. The main really interesting FF Sigma lenses missing are the longer macros. Have to wait and see if they work but perhaps w/o AF.

Link | Posted on Feb 23, 2016 at 21:14 UTC
In reply to:

Jekabs: This only makes sense for E-mount if:
- is very reliable with Sigma lenses and does not occasionally require a power cycle or re-mount of the lens or adapter;
- allows advanced tracking modes like Eye-AF, which are not available on adapters which emulate LA-EA1/3.

Sigma lists 15 lenses (http://www.sigma-global.com/en/lenses/cas/product/accessories/mount-converter/#focus), why do you claim only 9?

Link | Posted on Feb 23, 2016 at 18:54 UTC
In reply to:

Jonneymendoza2: Will Eye-AF work?

The triumph of hope over experience.

Link | Posted on Feb 23, 2016 at 16:30 UTC
In reply to:

Jonneymendoza2: Will Eye-AF work?

Direct link: http://www.sigma-global.com/en/lenses/cas/product/accessories/mount-converter/#focus

Link | Posted on Feb 23, 2016 at 14:21 UTC
In reply to:

Jonneymendoza2: Will Eye-AF work?

If this post is correct then AFC/AFA will not work http://www.dpreview.com/forums/post/57325515

Link | Posted on Feb 23, 2016 at 14:03 UTC
In reply to:

NilsBV: Prices for those orphaned Sigma-mount lenses on eBay might suddenly go up, now that they are being given a new lease on life.

Sorry, it says right on the adapter "Designated lenses only". So unless the orphan is an Art, Sport or Contemporary it's not gonna be supported.

Link | Posted on Feb 23, 2016 at 13:38 UTC
In reply to:

sportyaccordy: Only two important questions.... 1 will it work on the original A7.... and 2 will it work with non Sigma glass? If the answer to either question is no, kinda useless....

Correction: 15 lenses including the new 50-100. The other 4 lenses in the "Global Vision" count are already E mount.

Link | Posted on Feb 23, 2016 at 13:33 UTC
Total: 264, showing: 1 – 20
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