Tom Schum

Tom Schum

Lives in United States Washington DC area, AK, United States
Works as a Electronics
Joined on Aug 30, 2010
About me:

Photo hobbyist, Sigma user


Total: 14, showing: 1 – 14
On A look at the Lomography Petzval 85mm F2.2 lens article (163 comments in total)
In reply to:

Tom Schum: If I were a working portrait photographer, this would be a must-have!

If I'm not mistaken low chromatic aberration is a hallmark of the Petzval design. Films of the time were sensitive to ultraviolet so to get good focus the lens had to treat the colors mostly the same.

Direct link | Posted on Jul 2, 2014 at 18:14 UTC
On A look at the Lomography Petzval 85mm F2.2 lens article (163 comments in total)

If I were a working portrait photographer, this would be a must-have!

Direct link | Posted on Jul 2, 2014 at 16:37 UTC as 84th comment | 7 replies


Direct link | Posted on Jun 14, 2014 at 15:21 UTC as 64th comment

If Sigma is working on a new DSLR or Mirrorless camera, this fine might put a serious dent in their schedule. We might be stuck with another year of delay in the Sigma development process.
On the one hand, patent infringement is a serious problem and ought to be enforced with fines. On the other hand there can be far-reaching effects against competition in a case such as this. Since Nikon was asking for ten times as much money as they actually got, the judgement seems lenient to me.
Thinking about in-lens image stabilization in general, it seems to me that there is not a whole lot of choice regarding how to do it: move a lens or an element of a lens. In-camera image stabilization is a similar situation: you move a sensor.
Either way, one false move and you have re-invented something previously patented, and there will be infringement issues to deal with. I doubt Sigma had any criminal intent. This is an area for the patent trolls.

Direct link | Posted on Mar 12, 2014 at 12:55 UTC as 23rd comment | 3 replies
On Welcome to our studio test scene article (275 comments in total)

The resolution lineset now goes to 50, but since the phase 1 IQ180 easily resolves this, my impression is the resolution lineset is going to soon be useless.

Direct link | Posted on Sep 18, 2013 at 23:12 UTC as 62nd comment

I still remain attracted by the latest and the greatest. As a previous poster said, financial limitations tend to moderate GAS.
At any moment I'm ready to drop $1000 on a new lens, or a new camera. Soon, the money might be there. Meanwhile I am enjoying using my existing equipment, and wondering why I want to buy more stuff.
Perhaps the best I can hope for is to be a recovering GASaholic.

Direct link | Posted on Jul 10, 2013 at 14:12 UTC as 67th comment
On Just Posted: Pentax K-5 II / K-5 IIS Review article (268 comments in total)

Looks like the K5 IIs makes a generally crisper and clearer photo. Too bad my X-E1 gives me a moire-free view of the resolution test chart. Perhaps the limits of bayer CFA technology have been reached.

Direct link | Posted on Jun 5, 2013 at 16:13 UTC as 18th comment | 1 reply

Quite a large lens, compared to the 18-55.

Direct link | Posted on Mar 6, 2013 at 16:36 UTC as 27th comment | 1 reply
On Nikon issues service advisory on D600's dust issue article (240 comments in total)

These hi-res sensors see ALL!
Also a serious issue with my Sigma SD1.
Will try (again) to set up a sensor cleaning service with Sigma USA.

Direct link | Posted on Feb 24, 2013 at 14:25 UTC as 26th comment
On A Serious Rangefinder Compact Camera article (137 comments in total)

A Sigma DP2M with interchangeable lens mount on the front. That's all I wish for.
At this rate I might have to settle for a Fuji X-Pro1 instead.

Direct link | Posted on Oct 22, 2012 at 00:09 UTC as 28th comment

If Fuji can pull this off with good success, their XPro-1 sales will see a boost.

Direct link | Posted on Mar 13, 2012 at 00:42 UTC as 68th comment

I think we are watching the end of the point-and-shoot: with phones getting this good, there is no longer a need for them.

Direct link | Posted on Feb 28, 2012 at 01:53 UTC as 127th comment

An image of mine remains mine only until somebody else complains that my image is too much like one of theirs.
This is depressing!

Direct link | Posted on Jan 30, 2012 at 00:59 UTC as 24th comment
On Preview:sigmasd1 (56 comments in total)

When will DP Review produce a full review of the SD1?

Posted on Aug 8, 2011 at 16:12 UTC as 21st comment | 1 reply
Total: 14, showing: 1 – 14