Sigma lens question at DVinfo.net

Stathis Athanasiou · January 25th, 2008, 04:48 PM

Has anyone used the Sigma 28-300mm f/3.5-6.3 DG ?
(http://www.bhphotovideo.com/c/produc..._DG_Macro.html)

Most importantly what I wanted to ask since I am new to SLR lenses, is whether this is a "Digital" lens and if so can it be used with the Letus Extreme, because I have read posts stating that Digital lenses should better be avoided.

Thanks :)

Jim Giberti · January 25th, 2008, 08:06 PM

As a general rule, yes...avoid digital lenses.
I deally you want to get solid prime lenses (we use Nikons) inorder to get a Cine-like focus and aperture control.

More importantly the speed of the Sigma you're looking at is simply way to slow for any 35mm adapter.
And zooms are mostly longer and heavier and slower and usually (unless you spend big $) not comparable to their prime counter parts.

So here's your basic goal: A set of manual primes, say Nikon ai, ais or even non ai (all optically similar).

A great inexpensive starter set would be a 35mm f/2, 50mm f/1.4 and an 85mm f/2. You could shoot a film with those three lenses (countless have been shot with that range). You could buy those three on ebay tonight for less about $500

Fill that out with a 24mm f/2.8 and 135mm f2.8 and you've got a full film making set for under a grand and four of five all use interchangeable filters and hoods.

For a great set, step up to the f/1.2 50mm, the f/1.4 35mm, and the f/1.4 85mm and you've got a killer kit. That 5 lens set will cost you around $2000 in mint condition...maybe a little less.

But you can start for $500.

Hope that helps.

Jim

Stathis Athanasiou · January 28th, 2008, 02:36 AM

Hello Jim, thanks for the reply.
I have many photographer friends and I have borrowed and used their lenses (eg the 50mm 1.2 and the 85mm 1.4) (magic!) and the thing is that I am not that much in a hurry of buying the best lenses around, because I can have access almost whenever I want to a great set of lenses. I was thinking of buying the sigma lens for having a decent lens with many focal lengths all of the time, and when needed steal my friend's lenses.
But is this a Digital lens? How can you tell? Does the "DG" stand for Digital?

Tom Hardwick · January 28th, 2008, 02:57 AM

When you say 'digital lens' there really is no such thing - they're all optical. Of course some SLR lenses have been designed to be smaller and lighter and cheaper while at the same time giving a smaller image circle. These lenses will vignette the 36 x 24 mm (35 mm) film frame, and are designed (generally) for the APS (C) frame and the smaller chips used in a lot of DSLRs.

tom.

Bob Hart · January 28th, 2008, 03:11 AM

Sigma's own website describes its lenses. There are codes which tell you if the lens is digital only or compatable with larger format film cameras.

From the website :-

QUOTE:

DG (DG Lens)
These are large-aperture lenses with wide angles and short minimum focusing distances. With an abundance of peripheral illumination, they are ideal lenses for Digital SLR Cameras whilst retaining suitability for traditional 35mm SLRs.

END OF QUOTE:

What I get from that is that a lens with DG after its name should be fine for a full frame stills film camera, so should probably be okay for the Letus providing you are not trying to stay back too far on the camcorder zoom to obtain max image area for best possible resolution. Your lens may go darker on the corners at the zoom end.

I use a Sigma 50mm - 500mm f4 - f6,3 on a home-made adaptor. If it takes a bump and the adaptor alignment goes off, an edge will darken but it is otherwise okay at slightly over the standard 24mm wide movie frame.

This was done with the Sigma :-

http://www.youtube.com/watch?v=4gnLzWVxdnI

Stathis Athanasiou · January 28th, 2008, 03:11 AM

Thanks Tom. That was clear.

How can you tell whether a lens is "digital" -ie will vignette the edges of the 35mm frame- if you shop online? I suspect it is this D after the f number, but I don't want to find out after I've bought the wrong item.
Cheers!

Stathis Athanasiou · January 28th, 2008, 03:13 AM

I posted before seeing the response by Bob. Thanks once again!

Stathis Athanasiou · January 28th, 2008, 04:39 AM

I went to Sigma and would like to add a quote from their site, adding to what Bob has already posted before, for those wanting to know what the codes stand for.

"The DG designation applied to most newer Sigma lenses indicates that the lens is especially suited for use with digital SLR cameras. The DG lenses feature improved (more even) light distribution from image center to edge, and incorporate the latest multi-layer lens coatings to avoid reflections of the sensors of digital cameras. This is important in digital photography, but is also useful in 35mm photography, especially when slide film is used. Lenses designated as DC are designed exclusively for use with digital cameras having APS-C size image sensors. They feature smaller image circles and often feature shorter focal lengths (e.g. 10-20mm DC, 17-70mm DC, 18-50mm DC, 18-200mm DC, etc.). The shorter focal lengths are desirable, because most digital SLR cameras have image sensors whose dimensions are considerably smaller than a 35mm negative (usually by a factor of 1.3X to 2.0X), making the lens’ angle of view equivalent to that of a longer lens on a 35mm cameras."

Jim Giberti · January 28th, 2008, 11:21 AM

Again though, this is simply too slow to use with an adapter. It starts out at 3.5 and at 6.3 the long end of the foal range is beyond the nominal "noise" threshold of ground glass. Plus it's not a true manual lens which means less than ideal focus.

Now the Extreme (still waiting for the HD100 version) is better than the original Letus, but even the $10k P+S adapter gets funky by 5.6 and would be unusable in many situations at 6.3.

Plus you aren't going to get much DOF or bokeh with that lens..certainly not anything comparable to reasonably fast primes.

Stathis Athanasiou · January 28th, 2008, 01:31 PM

Yes I see what you mean. I borrowed a Nikon 80-200mm f4.5 (even slower) and shot some tests with it, and the noise was way too obvious.

January 25th, 2008, 04:48 PM	#1
Stathis Athanasiou Regular Crew Join Date: Jun 2007 Location: Athens, Hellas Posts: 73	Sigma lens question Has anyone used the Sigma 28-300mm f/3.5-6.3 DG ? (http://www.bhphotovideo.com/c/produc..._DG_Macro.html) Most importantly what I wanted to ask since I am new to SLR lenses, is whether this is a "Digital" lens and if so can it be used with the Letus Extreme, because I have read posts stating that Digital lenses should better be avoided. Thanks :) Last edited by Stathis Athanasiou; January 25th, 2008 at 05:39 PM.

January 28th, 2008, 03:11 AM	#5
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	Sigma's own website describes its lenses. There are codes which tell you if the lens is digital only or compatable with larger format film cameras. From the website :- QUOTE: DG (DG Lens) These are large-aperture lenses with wide angles and short minimum focusing distances. With an abundance of peripheral illumination, they are ideal lenses for Digital SLR Cameras whilst retaining suitability for traditional 35mm SLRs. END OF QUOTE: What I get from that is that a lens with DG after its name should be fine for a full frame stills film camera, so should probably be okay for the Letus providing you are not trying to stay back too far on the camcorder zoom to obtain max image area for best possible resolution. Your lens may go darker on the corners at the zoom end. I use a Sigma 50mm - 500mm f4 - f6,3 on a home-made adaptor. If it takes a bump and the adaptor alignment goes off, an edge will darken but it is otherwise okay at slightly over the standard 24mm wide movie frame. This was done with the Sigma :- http://www.youtube.com/watch?v=4gnLzWVxdnI Last edited by Bob Hart; January 28th, 2008 at 03:33 AM. Reason: added info

January 25th, 2008, 08:06 PM	#2
Jim Giberti Major Player Join Date: Aug 2002 Location: Bethel, VT Posts: 824	As a general rule, yes...avoid digital lenses. I deally you want to get solid prime lenses (we use Nikons) inorder to get a Cine-like focus and aperture control. More importantly the speed of the Sigma you're looking at is simply way to slow for any 35mm adapter. And zooms are mostly longer and heavier and slower and usually (unless you spend big $) not comparable to their prime counter parts. So here's your basic goal: A set of manual primes, say Nikon ai, ais or even non ai (all optically similar). A great inexpensive starter set would be a 35mm f/2, 50mm f/1.4 and an 85mm f/2. You could shoot a film with those three lenses (countless have been shot with that range). You could buy those three on ebay tonight for less about $500 Fill that out with a 24mm f/2.8 and 135mm f2.8 and you've got a full film making set for under a grand and four of five all use interchangeable filters and hoods. For a great set, step up to the f/1.2 50mm, the f/1.4 35mm, and the f/1.4 85mm and you've got a killer kit. That 5 lens set will cost you around $2000 in mint condition...maybe a little less. But you can start for $500. Hope that helps. Jim

January 28th, 2008, 02:36 AM	#3
Stathis Athanasiou Regular Crew Join Date: Jun 2007 Location: Athens, Hellas Posts: 73	Hello Jim, thanks for the reply. I have many photographer friends and I have borrowed and used their lenses (eg the 50mm 1.2 and the 85mm 1.4) (magic!) and the thing is that I am not that much in a hurry of buying the best lenses around, because I can have access almost whenever I want to a great set of lenses. I was thinking of buying the sigma lens for having a decent lens with many focal lengths all of the time, and when needed steal my friend's lenses. But is this a Digital lens? How can you tell? Does the "DG" stand for Digital?

January 28th, 2008, 02:57 AM	#4
Tom Hardwick Inner Circle Join Date: Mar 2003 Location: Billericay, England UK Posts: 4,711	When you say 'digital lens' there really is no such thing - they're all optical. Of course some SLR lenses have been designed to be smaller and lighter and cheaper while at the same time giving a smaller image circle. These lenses will vignette the 36 x 24 mm (35 mm) film frame, and are designed (generally) for the APS (C) frame and the smaller chips used in a lot of DSLRs. tom.

January 28th, 2008, 03:13 AM	#7
Stathis Athanasiou Regular Crew Join Date: Jun 2007 Location: Athens, Hellas Posts: 73	I posted before seeing the response by Bob. Thanks once again!

January 28th, 2008, 04:39 AM	#8
Stathis Athanasiou Regular Crew Join Date: Jun 2007 Location: Athens, Hellas Posts: 73	I went to Sigma and would like to add a quote from their site, adding to what Bob has already posted before, for those wanting to know what the codes stand for. "The DG designation applied to most newer Sigma lenses indicates that the lens is especially suited for use with digital SLR cameras. The DG lenses feature improved (more even) light distribution from image center to edge, and incorporate the latest multi-layer lens coatings to avoid reflections of the sensors of digital cameras. This is important in digital photography, but is also useful in 35mm photography, especially when slide film is used. Lenses designated as DC are designed exclusively for use with digital cameras having APS-C size image sensors. They feature smaller image circles and often feature shorter focal lengths (e.g. 10-20mm DC, 17-70mm DC, 18-50mm DC, 18-200mm DC, etc.). The shorter focal lengths are desirable, because most digital SLR cameras have image sensors whose dimensions are considerably smaller than a 35mm negative (usually by a factor of 1.3X to 2.0X), making the lens’ angle of view equivalent to that of a longer lens on a 35mm cameras."

January 28th, 2008, 11:21 AM	#9
Jim Giberti Major Player Join Date: Aug 2002 Location: Bethel, VT Posts: 824	Again though, this is simply too slow to use with an adapter. It starts out at 3.5 and at 6.3 the long end of the foal range is beyond the nominal "noise" threshold of ground glass. Plus it's not a true manual lens which means less than ideal focus. Now the Extreme (still waiting for the HD100 version) is better than the original Letus, but even the $10k P+S adapter gets funky by 5.6 and would be unusable in many situations at 6.3. Plus you aren't going to get much DOF or bokeh with that lens..certainly not anything comparable to reasonably fast primes.

January 28th, 2008, 01:31 PM	#10
Stathis Athanasiou Regular Crew Join Date: Jun 2007 Location: Athens, Hellas Posts: 73	Yes I see what you mean. I borrowed a Nikon 80-200mm f4.5 (even slower) and shot some tests with it, and the noise was way too obvious.